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Diffstat (limited to 'contrib/libpng/pngvalid.c')
| -rw-r--r-- | contrib/libpng/pngvalid.c | 6658 |
1 files changed, 0 insertions, 6658 deletions
diff --git a/contrib/libpng/pngvalid.c b/contrib/libpng/pngvalid.c deleted file mode 100644 index faebe4b..0000000 --- a/contrib/libpng/pngvalid.c +++ /dev/null @@ -1,6658 +0,0 @@ - -/* pngvalid.c - validate libpng by constructing then reading png files. - * - * Last changed in libpng 1.5.1 [February 3, 2011] - * Copyright (c) 2011 Glenn Randers-Pehrson - * Written by John Cunningham Bowler - * - * This code is released under the libpng license. - * For conditions of distribution and use, see the disclaimer - * and license in png.h - * - * NOTES: - * This is a C program that is intended to be linked against libpng. It - * generates bitmaps internally, stores them as PNG files (using the - * sequential write code) then reads them back (using the sequential - * read code) and validates that the result has the correct data. - * - * The program can be modified and extended to test the correctness of - * transformations performed by libpng. - */ - -#include "png.h" -#if PNG_LIBPNG_VER < 10500 -/* This delibarately lacks the PNG_CONST. */ -typedef png_byte *png_const_bytep; - -/* This is copied from 1.5.1 png.h: */ -#define PNG_INTERLACE_ADAM7_PASSES 7 -#define PNG_PASS_START_ROW(pass) (((1U&~(pass))<<(3-((pass)>>1)))&7) -#define PNG_PASS_START_COL(pass) (((1U& (pass))<<(3-(((pass)+1)>>1)))&7) -#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) -#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) -#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\ - -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) -#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\ - -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) -#define PNG_ROW_FROM_PASS_ROW(yIn, pass) \ - (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass)) -#define PNG_COL_FROM_PASS_COL(xIn, pass) \ - (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass)) -#define PNG_PASS_MASK(pass,off) ( \ - ((0x110145AFU>>(((7-(off))-(pass))<<2)) & 0xFU) | \ - ((0x01145AF0U>>(((7-(off))-(pass))<<2)) & 0xF0U)) -#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ - ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) -#define PNG_COL_IN_INTERLACE_PASS(x, pass) \ - ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) - -/* These are needed too for the defualt build: */ -#define PNG_WRITE_16BIT_SUPPORTED -#define PNG_READ_16BIT_SUPPORTED -#endif - -#include "zlib.h" /* For crc32 */ - -#include <float.h> /* For floating point constants */ -#include <stdlib.h> /* For malloc */ -#include <string.h> /* For memcpy, memset */ -#include <math.h> /* For floor */ - -/* Unused formal parameter errors are removed using the following macro which is - * expected to have no bad effects on performance. - */ -#ifndef UNUSED -# if defined(__GNUC__) || defined(_MSC_VER) -# define UNUSED(param) (void)param; -# else -# define UNUSED(param) -# endif -#endif - -/***************************** EXCEPTION HANDLING *****************************/ -#include "contrib/visupng/cexcept.h" -struct png_store; -define_exception_type(struct png_store*); - -/* The following are macros to reduce typing everywhere where the well known - * name 'the_exception_context' must be defined. - */ -#define anon_context(ps) struct exception_context *the_exception_context = \ - &(ps)->exception_context -#define context(ps,fault) anon_context(ps); png_store *fault - -/******************************* UTILITIES ************************************/ -/* Error handling is particularly problematic in production code - error - * handlers often themselves have bugs which lead to programs that detect - * minor errors crashing. The following functions deal with one very - * common class of errors in error handlers - attempting to format error or - * warning messages into buffers that are too small. - */ -static size_t safecat(char *buffer, size_t bufsize, size_t pos, - PNG_CONST char *cat) -{ - while (pos < bufsize && cat != NULL && *cat != 0) - buffer[pos++] = *cat++; - - if (pos >= bufsize) - pos = bufsize-1; - - buffer[pos] = 0; - return pos; -} - -static size_t safecatn(char *buffer, size_t bufsize, size_t pos, int n) -{ - char number[64]; - sprintf(number, "%d", n); - return safecat(buffer, bufsize, pos, number); -} - -static size_t safecatd(char *buffer, size_t bufsize, size_t pos, double d, - int precision) -{ - char number[64]; - sprintf(number, "%.*f", precision, d); - return safecat(buffer, bufsize, pos, number); -} - -static PNG_CONST char invalid[] = "invalid"; -static PNG_CONST char sep[] = ": "; - -/* NOTE: this is indexed by ln2(bit_depth)! */ -static PNG_CONST char *bit_depths[8] = -{ - "1", "2", "4", "8", "16", invalid, invalid, invalid -}; - -static PNG_CONST char *colour_types[8] = -{ - "greyscale", invalid, "truecolour", "indexed-colour", - "greyscale with alpha", invalid, "truecolour with alpha", invalid -}; - -/* To get log-bit-depth from bit depth, returns 0 to 7 (7 on error). */ -static unsigned int -log2depth(png_byte bit_depth) -{ - switch (bit_depth) - { - case 1: - return 0; - - case 2: - return 1; - - case 4: - return 2; - - case 8: - return 3; - - case 16: - return 4; - - default: - return 7; - } -} - -/* A numeric ID based on PNG file characteristics. The 'do_interlace' field - * simply records whether pngvalid did the interlace itself or whether it - * was done by libpng. Width and height must be less than 256. - */ -#define FILEID(col, depth, interlace, width, height, do_interlace) \ - ((png_uint_32)((col) + ((depth)<<3) + ((interlace)<<8) + \ - (((do_interlace)!=0)<<15) + ((width)<<16) + ((height)<<24))) - -#define COL_FROM_ID(id) ((png_byte)((id)& 0x7U)) -#define DEPTH_FROM_ID(id) ((png_byte)(((id) >> 3) & 0x1fU)) -#define INTERLACE_FROM_ID(id) ((int)(((id) >> 8) & 0x3)) -#define DO_INTERLACE_FROM_ID(id) ((int)(((id)>>15) & 1)) -#define WIDTH_FROM_ID(id) (((id)>>16) & 0xff) -#define HEIGHT_FROM_ID(id) (((id)>>24) & 0xff) - -/* Utility to construct a standard name for a standard image. */ -static size_t -standard_name(char *buffer, size_t bufsize, size_t pos, png_byte colour_type, - int log_bit_depth, int interlace_type, png_uint_32 w, png_uint_32 h, - int do_interlace) -{ - pos = safecat(buffer, bufsize, pos, colour_types[colour_type]); - pos = safecat(buffer, bufsize, pos, " "); - pos = safecat(buffer, bufsize, pos, bit_depths[log_bit_depth]); - pos = safecat(buffer, bufsize, pos, " bit "); - - if (interlace_type != PNG_INTERLACE_NONE) - pos = safecat(buffer, bufsize, pos, "interlaced"); - if (do_interlace) - pos = safecat(buffer, bufsize, pos, "(pngvalid)"); - else - pos = safecat(buffer, bufsize, pos, "(libpng)"); - if (w > 0 || h > 0) - { - pos = safecat(buffer, bufsize, pos, " "); - pos = safecatn(buffer, bufsize, pos, w); - pos = safecat(buffer, bufsize, pos, "x"); - pos = safecatn(buffer, bufsize, pos, h); - } - - return pos; -} - -static size_t -standard_name_from_id(char *buffer, size_t bufsize, size_t pos, png_uint_32 id) -{ - return standard_name(buffer, bufsize, pos, COL_FROM_ID(id), - log2depth(DEPTH_FROM_ID(id)), INTERLACE_FROM_ID(id), - WIDTH_FROM_ID(id), HEIGHT_FROM_ID(id), DO_INTERLACE_FROM_ID(id)); -} - -/* Convenience API and defines to list valid formats. Note that 16 bit read and - * write support is required to do 16 bit read tests (we must be able to make a - * 16 bit image to test!) - */ -#ifdef PNG_WRITE_16BIT_SUPPORTED -# define WRITE_BDHI 4 -# ifdef PNG_READ_16BIT_SUPPORTED -# define READ_BDHI 4 -# define DO_16BIT -# endif -#else -# define WRITE_BDHI 3 -#endif -#ifndef DO_16BIT -# define READ_BDHI 3 -#endif - -static int -next_format(png_bytep colour_type, png_bytep bit_depth) -{ - if (*bit_depth == 0) - { - *colour_type = 0, *bit_depth = 1; - return 1; - } - - *bit_depth = (png_byte)(*bit_depth << 1); - - /* Palette images are restricted to 8 bit depth */ - if (*bit_depth <= 8 -# ifdef DO_16BIT - || (*colour_type != 3 && *bit_depth <= 16) -# endif - ) - return 1; - - /* Move to the next color type, or return 0 at the end. */ - switch (*colour_type) - { - case 0: - *colour_type = 2; - *bit_depth = 8; - return 1; - - case 2: - *colour_type = 3; - *bit_depth = 1; - return 1; - - case 3: - *colour_type = 4; - *bit_depth = 8; - return 1; - - case 4: - *colour_type = 6; - *bit_depth = 8; - return 1; - - default: - return 0; - } -} - -static unsigned int -sample(png_const_bytep row, png_byte colour_type, png_byte bit_depth, - png_uint_32 x, unsigned int sample_index) -{ - png_uint_32 bit_index, result; - - /* Find a sample index for the desired sample: */ - x *= bit_depth; - bit_index = x; - - if ((colour_type & 1) == 0) /* !palette */ - { - if (colour_type & 2) - bit_index *= 3; - - if (colour_type & 4) - bit_index += x; /* Alpha channel */ - - if (colour_type & (2+4)) - bit_index += sample_index * bit_depth; /* Multiple channels: select one */ - } - - /* Return the sample from the row as an integer. */ - row += bit_index >> 3; - result = *row; - - if (bit_depth == 8) - return result; - - else if (bit_depth > 8) - return (result << 8) + *++row; - - /* Less than 8 bits per sample. */ - bit_index &= 7; - return (result >> (8-bit_index-bit_depth)) & ((1U<<bit_depth)-1); -} - -/* Copy a single pixel, of a given size, from one buffer to another - - * while this is basically bit addressed there is an implicit assumption - * that pixels 8 or more bits in size are byte aligned and that pixels - * do not otherwise cross byte boundaries. (This is, so far as I know, - * universally true in bitmap computer graphics. [JCB 20101212]) - * - * NOTE: The to and from buffers may be the same. - */ -static void -pixel_copy(png_bytep toBuffer, png_uint_32 toIndex, - png_const_bytep fromBuffer, png_uint_32 fromIndex, unsigned int pixelSize) -{ - /* Assume we can multiply by 'size' without overflow because we are - * just working in a single buffer. - */ - toIndex *= pixelSize; - fromIndex *= pixelSize; - if (pixelSize < 8) /* Sub-byte */ - { - /* Mask to select the location of the copied pixel: */ - unsigned int destMask = ((1U<<pixelSize)-1) << (8-pixelSize-(toIndex&7)); - /* The following read the entire pixels and clears the extra: */ - unsigned int destByte = toBuffer[toIndex >> 3] & ~destMask; - unsigned int sourceByte = fromBuffer[fromIndex >> 3]; - - /* Don't rely on << or >> supporting '0' here, just in case: */ - fromIndex &= 7; - if (fromIndex > 0) sourceByte <<= fromIndex; - if ((toIndex & 7) > 0) sourceByte >>= toIndex & 7; - - toBuffer[toIndex >> 3] = (png_byte)(destByte | (sourceByte & destMask)); - } - else /* One or more bytes */ - memmove(toBuffer+(toIndex>>3), fromBuffer+(fromIndex>>3), pixelSize>>3); -} - -/* Compare pixels - they are assumed to start at the first byte in the - * given buffers. - */ -static int -pixel_cmp(png_const_bytep pa, png_const_bytep pb, png_uint_32 bit_width) -{ - if (memcmp(pa, pb, bit_width>>3) == 0) - { - png_uint_32 p; - - if ((bit_width & 7) == 0) return 0; - - /* Ok, any differences? */ - p = pa[bit_width >> 3]; - p ^= pb[bit_width >> 3]; - - if (p == 0) return 0; - - /* There are, but they may not be significant, remove the bits - * after the end (the low order bits in PNG.) - */ - bit_width &= 7; - p >>= 8-bit_width; - - if (p == 0) return 0; - } - - return 1; /* Different */ -} - -/*************************** BASIC PNG FILE WRITING ***************************/ -/* A png_store takes data from the sequential writer or provides data - * to the sequential reader. It can also store the result of a PNG - * write for later retrieval. - */ -#define STORE_BUFFER_SIZE 500 /* arbitrary */ -typedef struct png_store_buffer -{ - struct png_store_buffer* prev; /* NOTE: stored in reverse order */ - png_byte buffer[STORE_BUFFER_SIZE]; -} png_store_buffer; - -#define FILE_NAME_SIZE 64 - -typedef struct png_store_file -{ - struct png_store_file* next; /* as many as you like... */ - char name[FILE_NAME_SIZE]; - png_uint_32 id; /* must be correct (see FILEID) */ - png_size_t datacount; /* In this (the last) buffer */ - png_store_buffer data; /* Last buffer in file */ -} png_store_file; - -/* The following is a pool of memory allocated by a single libpng read or write - * operation. - */ -typedef struct store_pool -{ - struct png_store *store; /* Back pointer */ - struct store_memory *list; /* List of allocated memory */ - png_byte mark[4]; /* Before and after data */ - - /* Statistics for this run. */ - png_alloc_size_t max; /* Maximum single allocation */ - png_alloc_size_t current; /* Current allocation */ - png_alloc_size_t limit; /* Highest current allocation */ - png_alloc_size_t total; /* Total allocation */ - - /* Overall statistics (retained across successive runs). */ - png_alloc_size_t max_max; - png_alloc_size_t max_limit; - png_alloc_size_t max_total; -} store_pool; - -typedef struct png_store -{ - /* For cexcept.h exception handling - simply store one of these; - * the context is a self pointer but it may point to a different - * png_store (in fact it never does in this program.) - */ - struct exception_context - exception_context; - - unsigned int verbose :1; - unsigned int treat_warnings_as_errors :1; - unsigned int expect_error :1; - unsigned int expect_warning :1; - unsigned int saw_warning :1; - unsigned int speed :1; - unsigned int progressive :1; /* use progressive read */ - unsigned int validated :1; /* used as a temporary flag */ - int nerrors; - int nwarnings; - char test[128]; /* Name of test */ - char error[256]; - - /* Read fields */ - png_structp pread; /* Used to read a saved file */ - png_infop piread; - png_store_file* current; /* Set when reading */ - png_store_buffer* next; /* Set when reading */ - png_size_t readpos; /* Position in *next */ - png_byte* image; /* Buffer for reading interlaced images */ - size_t cb_image; /* Size of this buffer */ - store_pool read_memory_pool; - - /* Write fields */ - png_store_file* saved; - png_structp pwrite; /* Used when writing a new file */ - png_infop piwrite; - png_size_t writepos; /* Position in .new */ - char wname[FILE_NAME_SIZE]; - png_store_buffer new; /* The end of the new PNG file being written. */ - store_pool write_memory_pool; -} png_store; - -/* Initialization and cleanup */ -static void -store_pool_mark(png_byte *mark) -{ - /* Generate a new mark. This uses a boring repeatable algorithm and it is - * implemented here so that it gives the same set of numbers on every - * architecture. It's a linear congruential generator (Knuth or Sedgewick - * "Algorithms") but it comes from the 'feedback taps' table in Horowitz and - * Hill, "The Art of Electronics". - */ - static png_uint_32 u0 = 0x12345678, u1 = 1; - - /* There are thirty three bits, the next bit in the sequence is bit-33 XOR - * bit-20. The top 1 bit is in u1, the bottom 32 are in u0. - */ - int i; - for (i=0; i<4; ++i) - { - /* First generate 8 new bits then shift them in at the end. */ - png_uint_32 u = ((u0 >> (20-8)) ^ ((u1 << 7) | (u0 >> (32-7)))) & 0xff; - u1 <<= 8; - u1 |= u0 >> 24; - u0 <<= 8; - u0 |= u; - *mark++ = (png_byte)u; - } -} - -/* Use this for random 32 bit values, this function makes sure the result is - * non-zero. - */ -static png_uint_32 -random_32(void) -{ - - for(;;) - { - png_byte mark[4]; - png_uint_32 result; - - store_pool_mark(mark); - result = png_get_uint_32(mark); - - if (result != 0) - return result; - } -} - -static void -store_pool_init(png_store *ps, store_pool *pool) -{ - memset(pool, 0, sizeof *pool); - - pool->store = ps; - pool->list = NULL; - pool->max = pool->current = pool->limit = pool->total = 0; - pool->max_max = pool->max_limit = pool->max_total = 0; - store_pool_mark(pool->mark); -} - -static void -store_init(png_store* ps) -{ - memset(ps, 0, sizeof *ps); - init_exception_context(&ps->exception_context); - store_pool_init(ps, &ps->read_memory_pool); - store_pool_init(ps, &ps->write_memory_pool); - ps->verbose = 0; - ps->treat_warnings_as_errors = 0; - ps->expect_error = 0; - ps->expect_warning = 0; - ps->saw_warning = 0; - ps->speed = 0; - ps->progressive = 0; - ps->validated = 0; - ps->nerrors = ps->nwarnings = 0; - ps->pread = NULL; - ps->piread = NULL; - ps->saved = ps->current = NULL; - ps->next = NULL; - ps->readpos = 0; - ps->image = NULL; - ps->cb_image = 0; - ps->pwrite = NULL; - ps->piwrite = NULL; - ps->writepos = 0; - ps->new.prev = NULL; -} - -/* This somewhat odd function is used when reading an image to ensure that the - * buffer is big enough - this is why a png_structp is available. - */ -static void -store_ensure_image(png_store *ps, png_structp pp, size_t cb) -{ - if (ps->cb_image < cb) - { - if (ps->image != NULL) - { - free(ps->image-1); - ps->cb_image = 0; - } - - /* The buffer is deliberately mis-aligned. */ - ps->image = malloc(cb+1); - if (ps->image == NULL) - png_error(pp, "OOM allocating image buffer"); - - ++(ps->image); - ps->cb_image = cb; - } - - /* And, for error checking, the whole buffer is set to '1' - this - * matches what happens with the 'size' test images on write and also - * matches the unused bits in the test rows. - */ - memset(ps->image, 0xff, cb); -} - -static void -store_freebuffer(png_store_buffer* psb) -{ - if (psb->prev) - { - store_freebuffer(psb->prev); - free(psb->prev); - psb->prev = NULL; - } -} - -static void -store_freenew(png_store *ps) -{ - store_freebuffer(&ps->new); - ps->writepos = 0; -} - -static void -store_storenew(png_store *ps) -{ - png_store_buffer *pb; - - if (ps->writepos != STORE_BUFFER_SIZE) - png_error(ps->pwrite, "invalid store call"); - - pb = malloc(sizeof *pb); - - if (pb == NULL) - png_error(ps->pwrite, "store new: OOM"); - - *pb = ps->new; - ps->new.prev = pb; - ps->writepos = 0; -} - -static void -store_freefile(png_store_file **ppf) -{ - if (*ppf != NULL) - { - store_freefile(&(*ppf)->next); - - store_freebuffer(&(*ppf)->data); - (*ppf)->datacount = 0; - free(*ppf); - *ppf = NULL; - } -} - -/* Main interface to file storeage, after writing a new PNG file (see the API - * below) call store_storefile to store the result with the given name and id. - */ -static void -store_storefile(png_store *ps, png_uint_32 id) -{ - png_store_file *pf = malloc(sizeof *pf); - if (pf == NULL) - png_error(ps->pwrite, "storefile: OOM"); - safecat(pf->name, sizeof pf->name, 0, ps->wname); - pf->id = id; - pf->data = ps->new; - pf->datacount = ps->writepos; - ps->new.prev = NULL; - ps->writepos = 0; - - /* And save it. */ - pf->next = ps->saved; - ps->saved = pf; -} - -/* Generate an error message (in the given buffer) */ -static size_t -store_message(png_store *ps, png_structp pp, char *buffer, size_t bufsize, - size_t pos, PNG_CONST char *msg) -{ - if (pp != NULL && pp == ps->pread) - { - /* Reading a file */ - pos = safecat(buffer, bufsize, pos, "read: "); - - if (ps->current != NULL) - { - pos = safecat(buffer, bufsize, pos, ps->current->name); - pos = safecat(buffer, bufsize, pos, sep); - } - } - - else if (pp != NULL && pp == ps->pwrite) - { - /* Writing a file */ - pos = safecat(buffer, bufsize, pos, "write: "); - pos = safecat(buffer, bufsize, pos, ps->wname); - pos = safecat(buffer, bufsize, pos, sep); - } - - else - { - /* Neither reading nor writing (or a memory error in struct delete) */ - pos = safecat(buffer, bufsize, pos, "pngvalid: "); - } - - if (ps->test[0] != 0) - { - pos = safecat(buffer, bufsize, pos, ps->test); - pos = safecat(buffer, bufsize, pos, sep); - } - pos = safecat(buffer, bufsize, pos, msg); - return pos; -} - -/* Log an error or warning - the relevant count is always incremented. */ -static void -store_log(png_store* ps, png_structp pp, png_const_charp message, int is_error) -{ - /* The warning is copied to the error buffer if there are no errors and it is - * the first warning. The error is copied to the error buffer if it is the - * first error (overwriting any prior warnings). - */ - if (is_error ? (ps->nerrors)++ == 0 : - (ps->nwarnings)++ == 0 && ps->nerrors == 0) - store_message(ps, pp, ps->error, sizeof ps->error, 0, message); - - if (ps->verbose) - { - char buffer[256]; - size_t pos; - - if (is_error) - pos = safecat(buffer, sizeof buffer, 0, "error: "); - else - pos = safecat(buffer, sizeof buffer, 0, "warning: "); - - store_message(ps, pp, buffer, sizeof buffer, pos, message); - fputs(buffer, stderr); - fputc('\n', stderr); - } -} - -/* Functions to use as PNG callbacks. */ -static void -store_error(png_structp pp, png_const_charp message) /* PNG_NORETURN */ -{ - png_store *ps = png_get_error_ptr(pp); - - if (!ps->expect_error) - store_log(ps, pp, message, 1 /* error */); - - /* And finally throw an exception. */ - { - struct exception_context *the_exception_context = &ps->exception_context; - Throw ps; - } -} - -static void -store_warning(png_structp pp, png_const_charp message) -{ - png_store *ps = png_get_error_ptr(pp); - - if (!ps->expect_warning) - store_log(ps, pp, message, 0 /* warning */); - else - ps->saw_warning = 1; -} - -static void -store_write(png_structp pp, png_bytep pb, png_size_t st) -{ - png_store *ps = png_get_io_ptr(pp); - - if (ps->pwrite != pp) - png_error(pp, "store state damaged"); - - while (st > 0) - { - size_t cb; - - if (ps->writepos >= STORE_BUFFER_SIZE) - store_storenew(ps); - - cb = st; - - if (cb > STORE_BUFFER_SIZE - ps->writepos) - cb = STORE_BUFFER_SIZE - ps->writepos; - - memcpy(ps->new.buffer + ps->writepos, pb, cb); - pb += cb; - st -= cb; - ps->writepos += cb; - } -} - -static void -store_flush(png_structp pp) -{ - UNUSED(pp) /*DOES NOTHING*/ -} - -static size_t -store_read_buffer_size(png_store *ps) -{ - /* Return the bytes available for read in the current buffer. */ - if (ps->next != &ps->current->data) - return STORE_BUFFER_SIZE; - - return ps->current->datacount; -} - -/* Return total bytes available for read. */ -static size_t -store_read_buffer_avail(png_store *ps) -{ - if (ps->current != NULL && ps->next != NULL) - { - png_store_buffer *next = &ps->current->data; - size_t cbAvail = ps->current->datacount; - - while (next != ps->next && next != NULL) - { - next = next->prev; - cbAvail += STORE_BUFFER_SIZE; - } - - if (next != ps->next) - png_error(ps->pread, "buffer read error"); - - if (cbAvail > ps->readpos) - return cbAvail - ps->readpos; - } - - return 0; -} - -static int -store_read_buffer_next(png_store *ps) -{ - png_store_buffer *pbOld = ps->next; - png_store_buffer *pbNew = &ps->current->data; - if (pbOld != pbNew) - { - while (pbNew != NULL && pbNew->prev != pbOld) - pbNew = pbNew->prev; - - if (pbNew != NULL) - { - ps->next = pbNew; - ps->readpos = 0; - return 1; - } - - png_error(ps->pread, "buffer lost"); - } - - return 0; /* EOF or error */ -} - -/* Need separate implementation and callback to allow use of the same code - * during progressive read, where the io_ptr is set internally by libpng. - */ -static void -store_read_imp(png_store *ps, png_bytep pb, png_size_t st) -{ - if (ps->current == NULL || ps->next == NULL) - png_error(ps->pread, "store state damaged"); - - while (st > 0) - { - size_t cbAvail = store_read_buffer_size(ps) - ps->readpos; - - if (cbAvail > 0) - { - if (cbAvail > st) cbAvail = st; - memcpy(pb, ps->next->buffer + ps->readpos, cbAvail); - st -= cbAvail; - pb += cbAvail; - ps->readpos += cbAvail; - } - - else if (!store_read_buffer_next(ps)) - png_error(ps->pread, "read beyond end of file"); - } -} - -static void -store_read(png_structp pp, png_bytep pb, png_size_t st) -{ - png_store *ps = png_get_io_ptr(pp); - - if (ps == NULL || ps->pread != pp) - png_error(pp, "bad store read call"); - - store_read_imp(ps, pb, st); -} - -static void -store_progressive_read(png_store *ps, png_structp pp, png_infop pi) -{ - /* Notice that a call to store_read will cause this function to fail because - * readpos will be set. - */ - if (ps->pread != pp || ps->current == NULL || ps->next == NULL) - png_error(pp, "store state damaged (progressive)"); - - do - { - if (ps->readpos != 0) - png_error(pp, "store_read called during progressive read"); - - png_process_data(pp, pi, ps->next->buffer, store_read_buffer_size(ps)); - } - while (store_read_buffer_next(ps)); -} - -/***************************** MEMORY MANAGEMENT*** ***************************/ -/* A store_memory is simply the header for an allocated block of memory. The - * pointer returned to libpng is just after the end of the header block, the - * allocated memory is followed by a second copy of the 'mark'. - */ -typedef struct store_memory -{ - store_pool *pool; /* Originating pool */ - struct store_memory *next; /* Singly linked list */ - png_alloc_size_t size; /* Size of memory allocated */ - png_byte mark[4]; /* ID marker */ -} store_memory; - -/* Handle a fatal error in memory allocation. This calls png_error if the - * libpng struct is non-NULL, else it outputs a message and returns. This means - * that a memory problem while libpng is running will abort (png_error) the - * handling of particular file while one in cleanup (after the destroy of the - * struct has returned) will simply keep going and free (or attempt to free) - * all the memory. - */ -static void -store_pool_error(png_store *ps, png_structp pp, PNG_CONST char *msg) -{ - if (pp != NULL) - png_error(pp, msg); - - /* Else we have to do it ourselves. png_error eventually calls store_log, - * above. store_log accepts a NULL png_structp - it just changes what gets - * output by store_message. - */ - store_log(ps, pp, msg, 1 /* error */); -} - -static void -store_memory_free(png_structp pp, store_pool *pool, store_memory *memory) -{ - /* Note that pp may be NULL (see store_pool_delete below), the caller has - * found 'memory' in pool->list *and* unlinked this entry, so this is a valid - * pointer (for sure), but the contents may have been trashed. - */ - if (memory->pool != pool) - store_pool_error(pool->store, pp, "memory corrupted (pool)"); - - else if (memcmp(memory->mark, pool->mark, sizeof memory->mark) != 0) - store_pool_error(pool->store, pp, "memory corrupted (start)"); - - /* It should be safe to read the size field now. */ - else - { - png_alloc_size_t cb = memory->size; - - if (cb > pool->max) - store_pool_error(pool->store, pp, "memory corrupted (size)"); - - else if (memcmp((png_bytep)(memory+1)+cb, pool->mark, sizeof pool->mark) - != 0) - store_pool_error(pool->store, pp, "memory corrupted (end)"); - - /* Finally give the library a chance to find problems too: */ - else - { - pool->current -= cb; - free(memory); - } - } -} - -static void -store_pool_delete(png_store *ps, store_pool *pool) -{ - if (pool->list != NULL) - { - fprintf(stderr, "%s: %s %s: memory lost (list follows):\n", ps->test, - pool == &ps->read_memory_pool ? "read" : "write", - pool == &ps->read_memory_pool ? (ps->current != NULL ? - ps->current->name : "unknown file") : ps->wname); - ++ps->nerrors; - - do - { - store_memory *next = pool->list; - pool->list = next->next; - next->next = NULL; - - fprintf(stderr, "\t%lu bytes @ %p\n", - (unsigned long)next->size, next+1); - /* The NULL means this will always return, even if the memory is - * corrupted. - */ - store_memory_free(NULL, pool, next); - } - while (pool->list != NULL); - } - - /* And reset the other fields too for the next time. */ - if (pool->max > pool->max_max) pool->max_max = pool->max; - pool->max = 0; - if (pool->current != 0) /* unexpected internal error */ - fprintf(stderr, "%s: %s %s: memory counter mismatch (internal error)\n", - ps->test, pool == &ps->read_memory_pool ? "read" : "write", - pool == &ps->read_memory_pool ? (ps->current != NULL ? - ps->current->name : "unknown file") : ps->wname); - pool->current = 0; - - if (pool->limit > pool->max_limit) - pool->max_limit = pool->limit; - - pool->limit = 0; - - if (pool->total > pool->max_total) - pool->max_total = pool->total; - - pool->total = 0; - - /* Get a new mark too. */ - store_pool_mark(pool->mark); -} - -/* The memory callbacks: */ -static png_voidp -store_malloc(png_structp pp, png_alloc_size_t cb) -{ - store_pool *pool = png_get_mem_ptr(pp); - store_memory *new = malloc(cb + (sizeof *new) + (sizeof pool->mark)); - - if (new != NULL) - { - if (cb > pool->max) - pool->max = cb; - - pool->current += cb; - - if (pool->current > pool->limit) - pool->limit = pool->current; - - pool->total += cb; - - new->size = cb; - memcpy(new->mark, pool->mark, sizeof new->mark); - memcpy((png_byte*)(new+1) + cb, pool->mark, sizeof pool->mark); - new->pool = pool; - new->next = pool->list; - pool->list = new; - ++new; - } - - else - store_pool_error(pool->store, pp, "out of memory"); - - return new; -} - -static void -store_free(png_structp pp, png_voidp memory) -{ - store_pool *pool = png_get_mem_ptr(pp); - store_memory *this = memory, **test; - - /* First check that this 'memory' really is valid memory - it must be in the - * pool list. If it is, use the shared memory_free function to free it. - */ - --this; - for (test = &pool->list; *test != this; test = &(*test)->next) - { - if (*test == NULL) - { - store_pool_error(pool->store, pp, "bad pointer to free"); - return; - } - } - - /* Unlink this entry, *test == this. */ - *test = this->next; - this->next = NULL; - store_memory_free(pp, pool, this); -} - -/* Setup functions. */ -/* Cleanup when aborting a write or after storing the new file. */ -static void -store_write_reset(png_store *ps) -{ - if (ps->pwrite != NULL) - { - anon_context(ps); - - Try - png_destroy_write_struct(&ps->pwrite, &ps->piwrite); - - Catch_anonymous - { - /* memory corruption: continue. */ - } - - ps->pwrite = NULL; - ps->piwrite = NULL; - } - - /* And make sure that all the memory has been freed - this will output - * spurious errors in the case of memory corruption above, but this is safe. - */ - store_pool_delete(ps, &ps->write_memory_pool); - - store_freenew(ps); -} - -/* The following is the main write function, it returns a png_struct and, - * optionally, a png_info suitable for writiing a new PNG file. Use - * store_storefile above to record this file after it has been written. The - * returned libpng structures as destroyed by store_write_reset above. - */ -static png_structp -set_store_for_write(png_store *ps, png_infopp ppi, - PNG_CONST char * volatile name) -{ - anon_context(ps); - - Try - { - if (ps->pwrite != NULL) - png_error(ps->pwrite, "write store already in use"); - - store_write_reset(ps); - safecat(ps->wname, sizeof ps->wname, 0, name); - - /* Don't do the slow memory checks if doing a speed test. */ - if (ps->speed) - ps->pwrite = png_create_write_struct(PNG_LIBPNG_VER_STRING, - ps, store_error, store_warning); - - else - ps->pwrite = png_create_write_struct_2(PNG_LIBPNG_VER_STRING, - ps, store_error, store_warning, &ps->write_memory_pool, - store_malloc, store_free); - - png_set_write_fn(ps->pwrite, ps, store_write, store_flush); - - if (ppi != NULL) - *ppi = ps->piwrite = png_create_info_struct(ps->pwrite); - } - - Catch_anonymous - return NULL; - - return ps->pwrite; -} - -/* Cleanup when finished reading (either due to error or in the success case). - */ -static void -store_read_reset(png_store *ps) -{ - if (ps->pread != NULL) - { - anon_context(ps); - - Try - png_destroy_read_struct(&ps->pread, &ps->piread, NULL); - - Catch_anonymous - { - /* error already output: continue */ - } - - ps->pread = NULL; - ps->piread = NULL; - } - - /* Always do this to be safe. */ - store_pool_delete(ps, &ps->read_memory_pool); - - ps->current = NULL; - ps->next = NULL; - ps->readpos = 0; - ps->validated = 0; -} - -static void -store_read_set(png_store *ps, png_uint_32 id) -{ - png_store_file *pf = ps->saved; - - while (pf != NULL) - { - if (pf->id == id) - { - ps->current = pf; - ps->next = NULL; - store_read_buffer_next(ps); - return; - } - - pf = pf->next; - } - - { - size_t pos; - char msg[FILE_NAME_SIZE+64]; - - pos = standard_name_from_id(msg, sizeof msg, 0, id); - pos = safecat(msg, sizeof msg, pos, ": file not found"); - png_error(ps->pread, msg); - } -} - -/* The main interface for reading a saved file - pass the id number of the file - * to retrieve. Ids must be unique or the earlier file will be hidden. The API - * returns a png_struct and, optionally, a png_info. Both of these will be - * destroyed by store_read_reset above. - */ -static png_structp -set_store_for_read(png_store *ps, png_infopp ppi, png_uint_32 id, - PNG_CONST char *name) -{ - /* Set the name for png_error */ - safecat(ps->test, sizeof ps->test, 0, name); - - if (ps->pread != NULL) - png_error(ps->pread, "read store already in use"); - - store_read_reset(ps); - - /* Both the create APIs can return NULL if used in their default mode - * (because there is no other way of handling an error because the jmp_buf - * by default is stored in png_struct and that has not been allocated!) - * However, given that store_error works correctly in these circumstances - * we don't ever expect NULL in this program. - */ - if (ps->speed) - ps->pread = png_create_read_struct(PNG_LIBPNG_VER_STRING, ps, - store_error, store_warning); - - else - ps->pread = png_create_read_struct_2(PNG_LIBPNG_VER_STRING, ps, - store_error, store_warning, &ps->read_memory_pool, store_malloc, - store_free); - - if (ps->pread == NULL) - { - struct exception_context *the_exception_context = &ps->exception_context; - - store_log(ps, NULL, "png_create_read_struct returned NULL (unexpected)", - 1 /*error*/); - - Throw ps; - } - - store_read_set(ps, id); - - if (ppi != NULL) - *ppi = ps->piread = png_create_info_struct(ps->pread); - - return ps->pread; -} - -/* The overall cleanup of a store simply calls the above then removes all the - * saved files. This does not delete the store itself. - */ -static void -store_delete(png_store *ps) -{ - store_write_reset(ps); - store_read_reset(ps); - store_freefile(&ps->saved); - - if (ps->image != NULL) - { - free(ps->image-1); - ps->image = NULL; - ps->cb_image = 0; - } -} - -/*********************** PNG FILE MODIFICATION ON READ ************************/ -/* Files may be modified on read. The following structure contains a complete - * png_store together with extra members to handle modification and a special - * read callback for libpng. To use this the 'modifications' field must be set - * to a list of png_modification structures that actually perform the - * modification, otherwise a png_modifier is functionally equivalent to a - * png_store. There is a special read function, set_modifier_for_read, which - * replaces set_store_for_read. - */ -typedef struct png_modifier -{ - png_store this; /* I am a png_store */ - struct png_modification *modifications; /* Changes to make */ - - enum modifier_state - { - modifier_start, /* Initial value */ - modifier_signature, /* Have a signature */ - modifier_IHDR /* Have an IHDR */ - } state; /* My state */ - - /* Information from IHDR: */ - png_byte bit_depth; /* From IHDR */ - png_byte colour_type; /* From IHDR */ - - /* While handling PLTE, IDAT and IEND these chunks may be pended to allow - * other chunks to be inserted. - */ - png_uint_32 pending_len; - png_uint_32 pending_chunk; - - /* Test values */ - double *gammas; - unsigned int ngammas; - - /* Lowest sbit to test (libpng fails for sbit < 8) */ - png_byte sbitlow; - - /* Error control - these are the limits on errors accepted by the gamma tests - * below. - */ - double maxout8; /* Maximum output value error */ - double maxabs8; /* Absolute sample error 0..1 */ - double maxpc8; /* Percentage sample error 0..100% */ - double maxout16; /* Maximum output value error */ - double maxabs16; /* Absolute sample error 0..1 */ - double maxpc16; /* Percentage sample error 0..100% */ - - /* Logged 8 and 16 bit errors ('output' values): */ - double error_gray_2; - double error_gray_4; - double error_gray_8; - double error_gray_16; - double error_color_8; - double error_color_16; - - /* Flags: */ - /* Whether or not to interlace. */ - int interlace_type :9; /* int, but must store '1' */ - - /* Run the standard tests? */ - unsigned int test_standard :1; - - /* Run the odd-sized image and interlace read/write tests? */ - unsigned int test_size :1; - - /* Run tests on reading with a combiniation of transforms, */ - unsigned int test_transform :1; - - /* When to use the use_input_precision option: */ - unsigned int use_input_precision :1; - unsigned int use_input_precision_sbit :1; - unsigned int use_input_precision_16to8 :1; - - /* Which gamma tests to run: */ - unsigned int test_gamma_threshold :1; - unsigned int test_gamma_transform :1; /* main tests */ - unsigned int test_gamma_sbit :1; - unsigned int test_gamma_strip16 :1; - - unsigned int log :1; /* Log max error */ - - /* Buffer information, the buffer size limits the size of the chunks that can - * be modified - they must fit (including header and CRC) into the buffer! - */ - size_t flush; /* Count of bytes to flush */ - size_t buffer_count; /* Bytes in buffer */ - size_t buffer_position; /* Position in buffer */ - png_byte buffer[1024]; -} png_modifier; - -static double abserr(png_modifier *pm, png_byte bit_depth) -{ - return bit_depth == 16 ? pm->maxabs16 : pm->maxabs8; -} - -static double pcerr(png_modifier *pm, png_byte bit_depth) -{ - return (bit_depth == 16 ? pm->maxpc16 : pm->maxpc8) * .01; -} - -static double outerr(png_modifier *pm, png_byte bit_depth) -{ - /* There is a serious error in the 2 and 4 bit grayscale transform because - * the gamma table value (8 bits) is simply shifted, not rounded, so the - * error in 4 bit greyscale gamma is up to the value below. This is a hack - * to allow pngvalid to succeed: - */ - if (bit_depth == 2) - return .73182-.5; - - if (bit_depth == 4) - return .90644-.5; - - if (bit_depth == 16) - return pm->maxout16; - - return pm->maxout8; -} - -/* This returns true if the test should be stopped now because it has already - * failed and it is running silently. - */ -static int fail(png_modifier *pm) -{ - return !pm->log && !pm->this.verbose && (pm->this.nerrors > 0 || - (pm->this.treat_warnings_as_errors && pm->this.nwarnings > 0)); -} - -static void -modifier_init(png_modifier *pm) -{ - memset(pm, 0, sizeof *pm); - store_init(&pm->this); - pm->modifications = NULL; - pm->state = modifier_start; - pm->sbitlow = 1U; - pm->maxout8 = pm->maxpc8 = pm->maxabs8 = 0; - pm->maxout16 = pm->maxpc16 = pm->maxabs16 = 0; - pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = 0; - pm->error_gray_16 = pm->error_color_8 = pm->error_color_16 = 0; - pm->interlace_type = PNG_INTERLACE_NONE; - pm->test_standard = 0; - pm->test_size = 0; - pm->test_transform = 0; - pm->use_input_precision = 0; - pm->use_input_precision_sbit = 0; - pm->use_input_precision_16to8 = 0; - pm->test_gamma_threshold = 0; - pm->test_gamma_transform = 0; - pm->test_gamma_sbit = 0; - pm->test_gamma_strip16 = 0; - pm->log = 0; - - /* Rely on the memset for all the other fields - there are no pointers */ -} - -/* One modification structure must be provided for each chunk to be modified (in - * fact more than one can be provided if multiple separate changes are desired - * for a single chunk.) Modifications include adding a new chunk when a - * suitable chunk does not exist. - * - * The caller of modify_fn will reset the CRC of the chunk and record 'modified' - * or 'added' as appropriate if the modify_fn returns 1 (true). If the - * modify_fn is NULL the chunk is simply removed. - */ -typedef struct png_modification -{ - struct png_modification *next; - png_uint_32 chunk; - - /* If the following is NULL all matching chunks will be removed: */ - int (*modify_fn)(struct png_modifier *pm, - struct png_modification *me, int add); - - /* If the following is set to PLTE, IDAT or IEND and the chunk has not been - * found and modified (and there is a modify_fn) the modify_fn will be called - * to add the chunk before the relevant chunk. - */ - png_uint_32 add; - unsigned int modified :1; /* Chunk was modified */ - unsigned int added :1; /* Chunk was added */ - unsigned int removed :1; /* Chunk was removed */ -} png_modification; - -static void modification_reset(png_modification *pmm) -{ - if (pmm != NULL) - { - pmm->modified = 0; - pmm->added = 0; - pmm->removed = 0; - modification_reset(pmm->next); - } -} - -static void -modification_init(png_modification *pmm) -{ - memset(pmm, 0, sizeof *pmm); - pmm->next = NULL; - pmm->chunk = 0; - pmm->modify_fn = NULL; - pmm->add = 0; - modification_reset(pmm); -} - -static void -modifier_reset(png_modifier *pm) -{ - store_read_reset(&pm->this); - pm->modifications = NULL; - pm->state = modifier_start; - pm->bit_depth = pm->colour_type = 0; - pm->pending_len = pm->pending_chunk = 0; - pm->flush = pm->buffer_count = pm->buffer_position = 0; -} - -/* Convenience macros. */ -#define CHUNK(a,b,c,d) (((a)<<24)+((b)<<16)+((c)<<8)+(d)) -#define CHUNK_IHDR CHUNK(73,72,68,82) -#define CHUNK_PLTE CHUNK(80,76,84,69) -#define CHUNK_IDAT CHUNK(73,68,65,84) -#define CHUNK_IEND CHUNK(73,69,78,68) -#define CHUNK_cHRM CHUNK(99,72,82,77) -#define CHUNK_gAMA CHUNK(103,65,77,65) -#define CHUNK_sBIT CHUNK(115,66,73,84) -#define CHUNK_sRGB CHUNK(115,82,71,66) - -/* The guts of modification are performed during a read. */ -static void -modifier_crc(png_bytep buffer) -{ - /* Recalculate the chunk CRC - a complete chunk must be in - * the buffer, at the start. - */ - uInt datalen = png_get_uint_32(buffer); - png_save_uint_32(buffer+datalen+8, crc32(0L, buffer+4, datalen+4)); -} - -static void -modifier_setbuffer(png_modifier *pm) -{ - modifier_crc(pm->buffer); - pm->buffer_count = png_get_uint_32(pm->buffer)+12; - pm->buffer_position = 0; -} - -/* Separate the callback into the actual implementation (which is passed the - * png_modifier explicitly) and the callback, which gets the modifier from the - * png_struct. - */ -static void -modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st) -{ - while (st > 0) - { - size_t cb; - png_uint_32 len, chunk; - png_modification *mod; - - if (pm->buffer_position >= pm->buffer_count) switch (pm->state) - { - static png_byte sign[8] = { 137, 80, 78, 71, 13, 10, 26, 10 }; - case modifier_start: - store_read_imp(&pm->this, pm->buffer, 8); /* size of signature. */ - pm->buffer_count = 8; - pm->buffer_position = 0; - - if (memcmp(pm->buffer, sign, 8) != 0) - png_error(pm->this.pread, "invalid PNG file signature"); - pm->state = modifier_signature; - break; - - case modifier_signature: - store_read_imp(&pm->this, pm->buffer, 13+12); /* size of IHDR */ - pm->buffer_count = 13+12; - pm->buffer_position = 0; - - if (png_get_uint_32(pm->buffer) != 13 || - png_get_uint_32(pm->buffer+4) != CHUNK_IHDR) - png_error(pm->this.pread, "invalid IHDR"); - - /* Check the list of modifiers for modifications to the IHDR. */ - mod = pm->modifications; - while (mod != NULL) - { - if (mod->chunk == CHUNK_IHDR && mod->modify_fn && - (*mod->modify_fn)(pm, mod, 0)) - { - mod->modified = 1; - modifier_setbuffer(pm); - } - - /* Ignore removal or add if IHDR! */ - mod = mod->next; - } - - /* Cache information from the IHDR (the modified one.) */ - pm->bit_depth = pm->buffer[8+8]; - pm->colour_type = pm->buffer[8+8+1]; - - pm->state = modifier_IHDR; - pm->flush = 0; - break; - - case modifier_IHDR: - default: - /* Read a new chunk and process it until we see PLTE, IDAT or - * IEND. 'flush' indicates that there is still some data to - * output from the preceding chunk. - */ - if ((cb = pm->flush) > 0) - { - if (cb > st) cb = st; - pm->flush -= cb; - store_read_imp(&pm->this, pb, cb); - pb += cb; - st -= cb; - if (st <= 0) return; - } - - /* No more bytes to flush, read a header, or handle a pending - * chunk. - */ - if (pm->pending_chunk != 0) - { - png_save_uint_32(pm->buffer, pm->pending_len); - png_save_uint_32(pm->buffer+4, pm->pending_chunk); - pm->pending_len = 0; - pm->pending_chunk = 0; - } - else - store_read_imp(&pm->this, pm->buffer, 8); - - pm->buffer_count = 8; - pm->buffer_position = 0; - - /* Check for something to modify or a terminator chunk. */ - len = png_get_uint_32(pm->buffer); - chunk = png_get_uint_32(pm->buffer+4); - - /* Terminators first, they may have to be delayed for added - * chunks - */ - if (chunk == CHUNK_PLTE || chunk == CHUNK_IDAT || - chunk == CHUNK_IEND) - { - mod = pm->modifications; - - while (mod != NULL) - { - if ((mod->add == chunk || - (mod->add == CHUNK_PLTE && chunk == CHUNK_IDAT)) && - mod->modify_fn != NULL && !mod->modified && !mod->added) - { - /* Regardless of what the modify function does do not run - * this again. - */ - mod->added = 1; - - if ((*mod->modify_fn)(pm, mod, 1 /*add*/)) - { - /* Reset the CRC on a new chunk */ - if (pm->buffer_count > 0) - modifier_setbuffer(pm); - - else - { - pm->buffer_position = 0; - mod->removed = 1; - } - - /* The buffer has been filled with something (we assume) - * so output this. Pend the current chunk. - */ - pm->pending_len = len; - pm->pending_chunk = chunk; - break; /* out of while */ - } - } - - mod = mod->next; - } - - /* Don't do any further processing if the buffer was modified - - * otherwise the code will end up modifying a chunk that was - * just added. - */ - if (mod != NULL) - break; /* out of switch */ - } - - /* If we get to here then this chunk may need to be modified. To - * do this it must be less than 1024 bytes in total size, otherwise - * it just gets flushed. - */ - if (len+12 <= sizeof pm->buffer) - { - store_read_imp(&pm->this, pm->buffer+pm->buffer_count, - len+12-pm->buffer_count); - pm->buffer_count = len+12; - - /* Check for a modification, else leave it be. */ - mod = pm->modifications; - while (mod != NULL) - { - if (mod->chunk == chunk) - { - if (mod->modify_fn == NULL) - { - /* Remove this chunk */ - pm->buffer_count = pm->buffer_position = 0; - mod->removed = 1; - break; /* Terminate the while loop */ - } - - else if ((*mod->modify_fn)(pm, mod, 0)) - { - mod->modified = 1; - /* The chunk may have been removed: */ - if (pm->buffer_count == 0) - { - pm->buffer_position = 0; - break; - } - modifier_setbuffer(pm); - } - } - - mod = mod->next; - } - } - - else - pm->flush = len+12 - pm->buffer_count; /* data + crc */ - - /* Take the data from the buffer (if there is any). */ - break; - } - - /* Here to read from the modifier buffer (not directly from - * the store, as in the flush case above.) - */ - cb = pm->buffer_count - pm->buffer_position; - - if (cb > st) - cb = st; - - memcpy(pb, pm->buffer + pm->buffer_position, cb); - st -= cb; - pb += cb; - pm->buffer_position += cb; - } -} - -/* The callback: */ -static void -modifier_read(png_structp pp, png_bytep pb, png_size_t st) -{ - png_modifier *pm = png_get_io_ptr(pp); - - if (pm == NULL || pm->this.pread != pp) - png_error(pp, "bad modifier_read call"); - - modifier_read_imp(pm, pb, st); -} - -/* Like store_progressive_read but the data is getting changed as we go so we - * need a local buffer. - */ -static void -modifier_progressive_read(png_modifier *pm, png_structp pp, png_infop pi) -{ - if (pm->this.pread != pp || pm->this.current == NULL || - pm->this.next == NULL) - png_error(pp, "store state damaged (progressive)"); - - /* This is another Horowitz and Hill random noise generator. In this case - * the aim is to stress the progressive reader with truely horrible variable - * buffer sizes in the range 1..500, so a sequence of 9 bit random numbers - * is generated. We could probably just count from 1 to 32767 and get as - * good a result. - */ - for (;;) - { - static png_uint_32 noise = 1; - png_size_t cb, cbAvail; - png_byte buffer[512]; - - /* Generate 15 more bits of stuff: */ - noise = (noise << 9) | ((noise ^ (noise >> (9-5))) & 0x1ff); - cb = noise & 0x1ff; - - /* Check that this number of bytes are available (in the current buffer.) - * (This doesn't quite work - the modifier might delete a chunk; unlikely - * but possible, it doesn't happen at present because the modifier only - * adds chunks to standard images.) - */ - cbAvail = store_read_buffer_avail(&pm->this); - if (pm->buffer_count > pm->buffer_position) - cbAvail += pm->buffer_count - pm->buffer_position; - - if (cb > cbAvail) - { - /* Check for EOF: */ - if (cbAvail == 0) - break; - - cb = cbAvail; - } - - modifier_read_imp(pm, buffer, cb); - png_process_data(pp, pi, buffer, cb); - } - - /* Check the invariants at the end (if this fails it's a problem in this - * file!) - */ - if (pm->buffer_count > pm->buffer_position || - pm->this.next != &pm->this.current->data || - pm->this.readpos < pm->this.current->datacount) - png_error(pp, "progressive read implementation error"); -} - -/* Set up a modifier. */ -static png_structp -set_modifier_for_read(png_modifier *pm, png_infopp ppi, png_uint_32 id, - PNG_CONST char *name) -{ - /* Do this first so that the modifier fields are cleared even if an error - * happens allocating the png_struct. No allocation is done here so no - * cleanup is required. - */ - pm->state = modifier_start; - pm->bit_depth = 0; - pm->colour_type = 255; - - pm->pending_len = 0; - pm->pending_chunk = 0; - pm->flush = 0; - pm->buffer_count = 0; - pm->buffer_position = 0; - - return set_store_for_read(&pm->this, ppi, id, name); -} - -/***************************** STANDARD PNG FILES *****************************/ -/* Standard files - write and save standard files. */ -/* There are two basic forms of standard images. Those which attempt to have - * all the possible pixel values (not possible for 16bpp images, but a range of - * values are produced) and those which have a range of image sizes. The former - * are used for testing transforms, in particular gamma correction and bit - * reduction and increase. The latter are reserved for testing the behavior of - * libpng with respect to 'odd' image sizes - particularly small images where - * rows become 1 byte and interlace passes disappear. - * - * The first, most useful, set are the 'transform' images, the second set of - * small images are the 'size' images. - * - * The transform files are constructed with rows which fit into a 1024 byte row - * buffer. This makes allocation easier below. Further regardless of the file - * format every row has 128 pixels (giving 1024 bytes for 64bpp formats). - * - * Files are stored with no gAMA or sBIT chunks, with a PLTE only when needed - * and with an ID derived from the colour type, bit depth and interlace type - * as above (FILEID). The width (128) and height (variable) are not stored in - * the FILEID - instead the fields are set to 0, indicating a transform file. - * - * The size files ar constructed with rows a maximum of 128 bytes wide, allowing - * a maximum width of 16 pixels (for the 64bpp case.) They also have a maximum - * height of 16 rows. The width and height are stored in the FILEID and, being - * non-zero, indicate a size file. - */ - -/* The number of passes is related to the interlace type. There wass no libpng - * API to determine this prior to 1.5, so we need an inquiry function: - */ -static int -npasses_from_interlace_type(png_structp pp, int interlace_type) -{ - switch (interlace_type) - { - default: - png_error(pp, "invalid interlace type"); - - case PNG_INTERLACE_NONE: - return 1; - - case PNG_INTERLACE_ADAM7: - return PNG_INTERLACE_ADAM7_PASSES; - } -} - -static unsigned int -bit_size(png_structp pp, png_byte colour_type, png_byte bit_depth) -{ - switch (colour_type) - { - case 0: return bit_depth; - - case 2: return 3*bit_depth; - - case 3: return bit_depth; - - case 4: return 2*bit_depth; - - case 6: return 4*bit_depth; - - default: png_error(pp, "invalid color type"); - } -} - -#define TRANSFORM_WIDTH 128U -#define TRANSFORM_ROWMAX (TRANSFORM_WIDTH*8U) -#define SIZE_ROWMAX (16*8U) /* 16 pixels, max 8 bytes each - 128 bytes */ -#define STANDARD_ROWMAX TRANSFORM_ROWMAX /* The larger of the two */ - -/* So the maximum image sizes are as follows. A 'transform' image may require - * more than 65535 bytes. The size images are a maximum of 2046 bytes. - */ -#define TRANSFORM_IMAGEMAX (TRANSFORM_ROWMAX * (png_uint_32)2048) -#define SIZE_IMAGEMAX (SIZE_ROWMAX * 16U) - -static size_t -transform_rowsize(png_structp pp, png_byte colour_type, png_byte bit_depth) -{ - return (TRANSFORM_WIDTH * bit_size(pp, colour_type, bit_depth)) / 8; -} - -/* transform_width(pp, colour_type, bit_depth) current returns the same number - * every time, so just use a macro: - */ -#define transform_width(pp, colour_type, bit_depth) TRANSFORM_WIDTH - -static png_uint_32 -transform_height(png_structp pp, png_byte colour_type, png_byte bit_depth) -{ - switch (bit_size(pp, colour_type, bit_depth)) - { - case 1: - case 2: - case 4: - return 1; /* Total of 128 pixels */ - - case 8: - return 2; /* Total of 256 pixels/bytes */ - - case 16: - return 512; /* Total of 65536 pixels */ - - case 24: - case 32: - return 512; /* 65536 pixels */ - - case 48: - case 64: - return 2048;/* 4 x 65536 pixels. */ - - default: - return 0; /* Error, will be caught later */ - } -} - -/* The following can only be defined here, now we have the definitions - * of the transform image sizes. - */ -static png_uint_32 -standard_width(png_structp pp, png_uint_32 id) -{ - png_uint_32 width = WIDTH_FROM_ID(id); - UNUSED(pp) - - if (width == 0) - width = transform_width(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id)); - - return width; -} - -static png_uint_32 -standard_height(png_structp pp, png_uint_32 id) -{ - png_uint_32 height = HEIGHT_FROM_ID(id); - - if (height == 0) - height = transform_height(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id)); - - return height; -} - -static png_uint_32 -standard_rowsize(png_structp pp, png_uint_32 id) -{ - png_uint_32 width = standard_width(pp, id); - - /* This won't overflow: */ - width *= bit_size(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id)); - return (width + 7) / 8; -} - -static void -transform_row(png_structp pp, png_byte buffer[TRANSFORM_ROWMAX], - png_byte colour_type, png_byte bit_depth, png_uint_32 y) -{ - png_uint_32 v = y << 7; - png_uint_32 i = 0; - - switch (bit_size(pp, colour_type, bit_depth)) - { - case 1: - while (i<128/8) buffer[i] = v & 0xff, v += 17, ++i; - return; - - case 2: - while (i<128/4) buffer[i] = v & 0xff, v += 33, ++i; - return; - - case 4: - while (i<128/2) buffer[i] = v & 0xff, v += 65, ++i; - return; - - case 8: - /* 256 bytes total, 128 bytes in each row set as follows: */ - while (i<128) buffer[i] = v & 0xff, ++v, ++i; - return; - - case 16: - /* Generate all 65536 pixel values in order, which includes the 8 bit - * GA case as well as the 16 bit G case. - */ - while (i<128) - buffer[2*i] = (v>>8) & 0xff, buffer[2*i+1] = v & 0xff, ++v, ++i; - - return; - - case 24: - /* 65535 pixels, but rotate the values. */ - while (i<128) - { - /* Three bytes per pixel, r, g, b, make b by r^g */ - buffer[3*i+0] = (v >> 8) & 0xff; - buffer[3*i+1] = v & 0xff; - buffer[3*i+2] = ((v >> 8) ^ v) & 0xff; - ++v; - ++i; - } - - return; - - case 32: - /* 65535 pixels, r, g, b, a; just replicate */ - while (i<128) - { - buffer[4*i+0] = (v >> 8) & 0xff; - buffer[4*i+1] = v & 0xff; - buffer[4*i+2] = (v >> 8) & 0xff; - buffer[4*i+3] = v & 0xff; - ++v; - ++i; - } - - return; - - case 48: - /* y is maximum 2047, giving 4x65536 pixels, make 'r' increase by 1 at - * each pixel, g increase by 257 (0x101) and 'b' by 0x1111: - */ - while (i<128) - { - png_uint_32 t = v++; - buffer[6*i+0] = (t >> 8) & 0xff; - buffer[6*i+1] = t & 0xff; - t *= 257; - buffer[6*i+2] = (t >> 8) & 0xff; - buffer[6*i+3] = t & 0xff; - t *= 17; - buffer[6*i+4] = (t >> 8) & 0xff; - buffer[6*i+5] = t & 0xff; - ++i; - } - - return; - - case 64: - /* As above in the 32 bit case. */ - while (i<128) - { - png_uint_32 t = v++; - buffer[8*i+0] = (t >> 8) & 0xff; - buffer[8*i+1] = t & 0xff; - buffer[8*i+4] = (t >> 8) & 0xff; - buffer[8*i+5] = t & 0xff; - t *= 257; - buffer[8*i+2] = (t >> 8) & 0xff; - buffer[8*i+3] = t & 0xff; - buffer[8*i+6] = (t >> 8) & 0xff; - buffer[8*i+7] = t & 0xff; - ++i; - } - return; - - default: - break; - } - - png_error(pp, "internal error"); -} - -/* This is just to do the right cast - could be changed to a function to check - * 'bd' but there isn't much point. - */ -#define DEPTH(bd) ((png_byte)(1U << (bd))) - -/* Make a standardized image given a an image colour type, bit depth and - * interlace type. The standard images have a very restricted range of - * rows and heights and are used for testing transforms rather than image - * layout details. See make_size_images below for a way to make images - * that test odd sizes along with the libpng interlace handling. - */ -static void -make_transform_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type, - png_byte PNG_CONST bit_depth, int interlace_type, png_const_charp name) -{ - context(ps, fault); - - Try - { - png_infop pi; - png_structp pp = set_store_for_write(ps, &pi, name); - png_uint_32 h; - - /* In the event of a problem return control to the Catch statement below - * to do the clean up - it is not possible to 'return' directly from a Try - * block. - */ - if (pp == NULL) - Throw ps; - - h = transform_height(pp, colour_type, bit_depth); - - png_set_IHDR(pp, pi, transform_width(pp, colour_type, bit_depth), h, - bit_depth, colour_type, interlace_type, - PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); - - if (colour_type == 3) /* palette */ - { - unsigned int i = 0; - png_color pal[256]; - - do - pal[i].red = pal[i].green = pal[i].blue = (png_byte)i; - while(++i < 256U); - - png_set_PLTE(pp, pi, pal, 256); - } - - png_write_info(pp, pi); - - if (png_get_rowbytes(pp, pi) != - transform_rowsize(pp, colour_type, bit_depth)) - png_error(pp, "row size incorrect"); - - else - { - /* Somewhat confusingly this must be called *after* png_write_info - * because if it is called before, the information in *pp has not been - * updated to reflect the interlaced image. - */ - int npasses = png_set_interlace_handling(pp); - int pass; - - if (npasses != npasses_from_interlace_type(pp, interlace_type)) - png_error(pp, "write: png_set_interlace_handling failed"); - - for (pass=0; pass<npasses; ++pass) - { - png_uint_32 y; - - for (y=0; y<h; ++y) - { - png_byte buffer[TRANSFORM_ROWMAX]; - - transform_row(pp, buffer, colour_type, bit_depth, y); - png_write_row(pp, buffer); - } - } - } - - png_write_end(pp, pi); - - /* And store this under the appropriate id, then clean up. */ - store_storefile(ps, FILEID(colour_type, bit_depth, interlace_type, - 0, 0, 0)); - - store_write_reset(ps); - } - - Catch(fault) - { - /* Use the png_store returned by the exception. This may help the compiler - * because 'ps' is not used in this branch of the setjmp. Note that fault - * and ps will always be the same value. - */ - store_write_reset(fault); - } -} - -static void -make_standard(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type, int bdlo, - int PNG_CONST bdhi) -{ - for (; bdlo <= bdhi; ++bdlo) - { - int interlace_type; - - for (interlace_type = PNG_INTERLACE_NONE; - interlace_type < PNG_INTERLACE_LAST; ++interlace_type) - { - char name[FILE_NAME_SIZE]; - - standard_name(name, sizeof name, 0, colour_type, bdlo, interlace_type, - 0, 0, 0); - make_transform_image(ps, colour_type, DEPTH(bdlo), interlace_type, - name); - } - } -} - -static void -make_transform_images(png_store *ps) -{ - /* This is in case of errors. */ - safecat(ps->test, sizeof ps->test, 0, "make standard images"); - - /* Arguments are colour_type, low bit depth, high bit depth - */ - make_standard(ps, 0, 0, WRITE_BDHI); - make_standard(ps, 2, 3, WRITE_BDHI); - make_standard(ps, 3, 0, 3 /*palette: max 8 bits*/); - make_standard(ps, 4, 3, WRITE_BDHI); - make_standard(ps, 6, 3, WRITE_BDHI); -} - -/* The following two routines use the PNG interlace support macros from - * png.h to interlace or deinterlace rows. - */ -static void -interlace_row(png_bytep buffer, png_const_bytep imageRow, - unsigned int pixel_size, png_uint_32 w, int pass) -{ - png_uint_32 xin, xout, xstep; - - /* Note that this can, trivially, be optimized to a memcpy on pass 7, the - * code is presented this way to make it easier to understand. In practice - * consult the code in the libpng source to see other ways of doing this. - */ - xin = PNG_PASS_START_COL(pass); - xstep = 1U<<PNG_PASS_COL_SHIFT(pass); - - for (xout=0; xin<w; xin+=xstep) - { - pixel_copy(buffer, xout, imageRow, xin, pixel_size); - ++xout; - } -} - -static void -deinterlace_row(png_bytep buffer, png_const_bytep row, - unsigned int pixel_size, png_uint_32 w, int pass) -{ - /* The inverse of the above, 'row' is part of row 'y' of the output image, - * in 'buffer'. The image is 'w' wide and this is pass 'pass', distribute - * the pixels of row into buffer and return the number written (to allow - * this to be checked). - */ - png_uint_32 xin, xout, xstep; - - xout = PNG_PASS_START_COL(pass); - xstep = 1U<<PNG_PASS_COL_SHIFT(pass); - - for (xin=0; xout<w; xout+=xstep) - { - pixel_copy(buffer, xout, row, xin, pixel_size); - ++xin; - } -} - -/* Build a single row for the 'size' test images, this fills in only the - * first bit_width bits of the sample row. - */ -static void -size_row(png_byte buffer[SIZE_ROWMAX], png_uint_32 bit_width, png_uint_32 y) -{ - /* height is in the range 1 to 16, so: */ - y = ((y & 1) << 7) + ((y & 2) << 6) + ((y & 4) << 5) + ((y & 8) << 4); - /* the following ensures bits are set in small images: */ - y ^= 0xA5; - - while (bit_width >= 8) - *buffer++ = (png_byte)y++, bit_width -= 8; - - /* There may be up to 7 remaining bits, these go in the most significant - * bits of the byte. - */ - if (bit_width > 0) - { - png_uint_32 mask = (1U<<(8-bit_width))-1; - *buffer = (png_byte)((*buffer & mask) | (y & ~mask)); - } -} - -static void -make_size_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type, - png_byte PNG_CONST bit_depth, int PNG_CONST interlace_type, - png_uint_32 PNG_CONST w, png_uint_32 PNG_CONST h, - int PNG_CONST do_interlace) -{ - context(ps, fault); - - Try - { - png_infop pi; - png_structp pp; - unsigned int pixel_size; - - /* Make a name and get an appropriate id for the store: */ - char name[FILE_NAME_SIZE]; - PNG_CONST png_uint_32 id = FILEID(colour_type, bit_depth, interlace_type, - w, h, do_interlace); - - standard_name_from_id(name, sizeof name, 0, id); - pp = set_store_for_write(ps, &pi, name); - - /* In the event of a problem return control to the Catch statement below - * to do the clean up - it is not possible to 'return' directly from a Try - * block. - */ - if (pp == NULL) - Throw ps; - - png_set_IHDR(pp, pi, w, h, bit_depth, colour_type, interlace_type, - PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); - - /* Same palette as make_transform_image - I don' think there is any - * benefit from using a different one (JB 20101211) - */ - if (colour_type == 3) /* palette */ - { - unsigned int i = 0; - png_color pal[256]; - - do - pal[i].red = pal[i].green = pal[i].blue = (png_byte)i; - while(++i < 256U); - - png_set_PLTE(pp, pi, pal, 256); - } - - png_write_info(pp, pi); - - /* Calculate the bit size, divide by 8 to get the byte size - this won't - * overflow because we know the w values are all small enough even for - * a system where 'unsigned int' is only 16 bits. - */ - pixel_size = bit_size(pp, colour_type, bit_depth); - if (png_get_rowbytes(pp, pi) != ((w * pixel_size) + 7) / 8) - png_error(pp, "row size incorrect"); - - else - { - int npasses = npasses_from_interlace_type(pp, interlace_type); - png_uint_32 y; - int pass; - png_byte image[16][SIZE_ROWMAX]; - - /* To help consistent error detection make the parts of this buffer - * that aren't set below all '1': - */ - memset(image, 0xff, sizeof image); - - if (!do_interlace && npasses != png_set_interlace_handling(pp)) - png_error(pp, "write: png_set_interlace_handling failed"); - - /* Prepare the whole image first to avoid making it 7 times: */ - for (y=0; y<h; ++y) - size_row(image[y], w * pixel_size, y); - - for (pass=0; pass<npasses; ++pass) - { - /* The following two are for checking the macros: */ - PNG_CONST png_uint_32 wPass = PNG_PASS_COLS(w, pass); - - /* If do_interlace is set we don't call png_write_row for every - * row because some of them are empty. In fact, for a 1x1 image, - * most of them are empty! - */ - for (y=0; y<h; ++y) - { - png_const_bytep row = image[y]; - png_byte tempRow[SIZE_ROWMAX]; - - /* If do_interlace *and* the image is interlaced we - * need a reduced interlace row, this may be reduced - * to empty. - */ - if (do_interlace && interlace_type == PNG_INTERLACE_ADAM7) - { - /* The row must not be written if it doesn't exist, notice - * that there are two conditions here, either the row isn't - * ever in the pass or the row would be but isn't wide - * enough to contribute any pixels. In fact the wPass test - * can be used to skip the whole y loop in this case. - */ - if (PNG_ROW_IN_INTERLACE_PASS(y, pass) && wPass > 0) - { - /* Set to all 1's for error detection (libpng tends to - * set unset things to 0). - */ - memset(tempRow, 0xff, sizeof tempRow); - interlace_row(tempRow, row, pixel_size, w, pass); - row = tempRow; - } - else - continue; - } - - /* Only get to here if the row has some pixels in it. */ - png_write_row(pp, row); - } - } - } - - png_write_end(pp, pi); - - /* And store this under the appropriate id, then clean up. */ - store_storefile(ps, id); - - store_write_reset(ps); - } - - Catch(fault) - { - /* Use the png_store returned by the exception. This may help the compiler - * because 'ps' is not used in this branch of the setjmp. Note that fault - * and ps will always be the same value. - */ - store_write_reset(fault); - } -} - -static void -make_size(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type, int bdlo, - int PNG_CONST bdhi) -{ - for (; bdlo <= bdhi; ++bdlo) - { - png_uint_32 width; - - for (width = 1; width <= 16; ++width) - { - png_uint_32 height; - - for (height = 1; height <= 16; ++height) - { - /* The four combinations of DIY interlace and interlace or not - - * no interlace + DIY should be identical to no interlace with - * libpng doing it. - */ - make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_NONE, - width, height, 0); - make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_NONE, - width, height, 1); - make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_ADAM7, - width, height, 0); - make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_ADAM7, - width, height, 1); - } - } - } -} - -static void -make_size_images(png_store *ps) -{ - /* This is in case of errors. */ - safecat(ps->test, sizeof ps->test, 0, "make size images"); - - /* Arguments are colour_type, low bit depth, high bit depth - */ - make_size(ps, 0, 0, WRITE_BDHI); - make_size(ps, 2, 3, WRITE_BDHI); - make_size(ps, 3, 0, 3 /*palette: max 8 bits*/); - make_size(ps, 4, 3, WRITE_BDHI); - make_size(ps, 6, 3, WRITE_BDHI); -} - -/* Return a row based on image id and 'y' for checking: */ -static void -standard_row(png_structp pp, png_byte std[STANDARD_ROWMAX], png_uint_32 id, - png_uint_32 y) -{ - if (WIDTH_FROM_ID(id) == 0) - transform_row(pp, std, COL_FROM_ID(id), DEPTH_FROM_ID(id), y); - else - size_row(std, WIDTH_FROM_ID(id) * bit_size(pp, COL_FROM_ID(id), - DEPTH_FROM_ID(id)), y); -} - -/* Tests - individual test cases */ -/* Like 'make_standard' but errors are deliberately introduced into the calls - * to ensure that they get detected - it should not be possible to write an - * invalid image with libpng! - */ -static void -sBIT0_error_fn(png_structp pp, png_infop pi) -{ - /* 0 is invalid... */ - png_color_8 bad; - bad.red = bad.green = bad.blue = bad.gray = bad.alpha = 0; - png_set_sBIT(pp, pi, &bad); -} - -static void -sBIT_error_fn(png_structp pp, png_infop pi) -{ - png_byte bit_depth; - png_color_8 bad; - - if (png_get_color_type(pp, pi) == PNG_COLOR_TYPE_PALETTE) - bit_depth = 8; - - else - bit_depth = png_get_bit_depth(pp, pi); - - /* Now we know the bit depth we can easily generate an invalid sBIT entry */ - bad.red = bad.green = bad.blue = bad.gray = bad.alpha = - (png_byte)(bit_depth+1); - png_set_sBIT(pp, pi, &bad); -} - -static PNG_CONST struct -{ - void (*fn)(png_structp, png_infop); - PNG_CONST char *msg; - unsigned int warning :1; /* the error is a warning... */ -} error_test[] = - { - { sBIT0_error_fn, "sBIT(0): failed to detect error", 1 }, - { sBIT_error_fn, "sBIT(too big): failed to detect error", 1 }, - }; - -static void -make_error(png_store* volatile ps, png_byte PNG_CONST colour_type, - png_byte bit_depth, int interlace_type, int test, png_const_charp name) -{ - context(ps, fault); - - Try - { - png_structp pp; - png_infop pi; - - pp = set_store_for_write(ps, &pi, name); - - if (pp == NULL) - Throw ps; - - png_set_IHDR(pp, pi, transform_width(pp, colour_type, bit_depth), - transform_height(pp, colour_type, bit_depth), bit_depth, colour_type, - interlace_type, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); - - if (colour_type == 3) /* palette */ - { - unsigned int i = 0; - png_color pal[256]; - - do - pal[i].red = pal[i].green = pal[i].blue = (png_byte)i; - while(++i < 256U); - - png_set_PLTE(pp, pi, pal, 256); - } - - /* Time for a few errors, these are in various optional chunks, the - * standard tests test the standard chunks pretty well. - */ -# define exception__prev exception_prev_1 -# define exception__env exception_env_1 - Try - { - /* Expect this to throw: */ - ps->expect_error = !error_test[test].warning; - ps->expect_warning = error_test[test].warning; - ps->saw_warning = 0; - error_test[test].fn(pp, pi); - - /* Normally the error is only detected here: */ - png_write_info(pp, pi); - - /* And handle the case where it was only a warning: */ - if (ps->expect_warning && ps->saw_warning) - Throw ps; - - /* If we get here there is a problem, we have success - no error or - * no warning - when we shouldn't have success. Log an error. - */ - store_log(ps, pp, error_test[test].msg, 1 /*error*/); - } - - Catch (fault) - ps = fault; /* expected exit, make sure ps is not clobbered */ -#undef exception__prev -#undef exception__env - - /* And clear these flags */ - ps->expect_error = 0; - ps->expect_warning = 0; - - /* Now write the whole image, just to make sure that the detected, or - * undetected, errro has not created problems inside libpng. - */ - if (png_get_rowbytes(pp, pi) != - transform_rowsize(pp, colour_type, bit_depth)) - png_error(pp, "row size incorrect"); - - else - { - png_uint_32 h = transform_height(pp, colour_type, bit_depth); - int npasses = png_set_interlace_handling(pp); - int pass; - - if (npasses != npasses_from_interlace_type(pp, interlace_type)) - png_error(pp, "write: png_set_interlace_handling failed"); - - for (pass=0; pass<npasses; ++pass) - { - png_uint_32 y; - - for (y=0; y<h; ++y) - { - png_byte buffer[TRANSFORM_ROWMAX]; - - transform_row(pp, buffer, colour_type, bit_depth, y); - png_write_row(pp, buffer); - } - } - } - - png_write_end(pp, pi); - - /* The following deletes the file that was just written. */ - store_write_reset(ps); - } - - Catch(fault) - { - store_write_reset(fault); - } -} - -static int -make_errors(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type, - int bdlo, int PNG_CONST bdhi) -{ - for (; bdlo <= bdhi; ++bdlo) - { - int interlace_type; - - for (interlace_type = PNG_INTERLACE_NONE; - interlace_type < PNG_INTERLACE_LAST; ++interlace_type) - { - unsigned int test; - char name[FILE_NAME_SIZE]; - - standard_name(name, sizeof name, 0, colour_type, bdlo, interlace_type, - 0, 0, 0); - - for (test=0; test<(sizeof error_test)/(sizeof error_test[0]); ++test) - { - make_error(&pm->this, colour_type, DEPTH(bdlo), interlace_type, - test, name); - - if (fail(pm)) - return 0; - } - } - } - - return 1; /* keep going */ -} - -static void -perform_error_test(png_modifier *pm) -{ - /* Need to do this here because we just write in this test. */ - safecat(pm->this.test, sizeof pm->this.test, 0, "error test"); - - if (!make_errors(pm, 0, 0, WRITE_BDHI)) - return; - - if (!make_errors(pm, 2, 3, WRITE_BDHI)) - return; - - if (!make_errors(pm, 3, 0, 3)) - return; - - if (!make_errors(pm, 4, 3, WRITE_BDHI)) - return; - - if (!make_errors(pm, 6, 3, WRITE_BDHI)) - return; -} - -/* Because we want to use the same code in both the progressive reader and the - * sequential reader it is necessary to deal with the fact that the progressive - * reader callbacks only have one parameter (png_get_progressive_ptr()), so this - * must contain all the test parameters and all the local variables directly - * accessible to the sequential reader implementation. - * - * The technique adopted is to reinvent part of what Dijkstra termed a - * 'display'; an array of pointers to the stack frames of enclosing functions so - * that a nested function definition can access the local (C auto) variables of - * the functions that contain its definition. In fact C provides the first - * pointer (the local variables - the stack frame pointer) and the last (the - * global variables - the BCPL global vector typically implemented as global - * addresses), this code requires one more pointer to make the display - the - * local variables (and function call parameters) of the function that actually - * invokes either the progressive or sequential reader. - * - * Perhaps confusingly this technique is confounded with classes - the - * 'standard_display' defined here is sub-classed as the 'gamma_display' below. - * A gamma_display is a standard_display, taking advantage of the ANSI-C - * requirement that the pointer to the first member of a structure must be the - * same as the pointer to the structure. This allows us to reuse standard_ - * functions in the gamma test code; something that could not be done with - * nested funtions! - */ -typedef struct standard_palette_entry /* pngvalid format palette! */ -{ - png_byte red; - png_byte green; - png_byte blue; - png_byte alpha; -} standard_palette[256]; - -typedef struct standard_display -{ - png_store* ps; /* Test parameters (passed to the function) */ - png_byte colour_type; - png_byte bit_depth; - png_byte red_sBIT; /* Input data sBIT values. */ - png_byte green_sBIT; - png_byte blue_sBIT; - png_byte alpha_sBIT; - int interlace_type; - png_uint_32 id; /* Calculated file ID */ - png_uint_32 w; /* Width of image */ - png_uint_32 h; /* Height of image */ - int npasses; /* Number of interlaced passes */ - png_uint_32 pixel_size; /* Width of one pixel in bits */ - png_uint_32 bit_width; /* Width of output row in bits */ - size_t cbRow; /* Bytes in a row of the output image */ - int do_interlace; /* Do interlacing internally */ - int is_transparent; /* Transparecy information was present. */ - struct - { - png_uint_16 red; - png_uint_16 green; - png_uint_16 blue; - } transparent; /* The transparent color, if set. */ - standard_palette - palette; -} standard_display; - -static void -standard_display_init(standard_display *dp, png_store* ps, png_uint_32 id, - int do_interlace) -{ - dp->ps = ps; - dp->colour_type = COL_FROM_ID(id); - dp->bit_depth = DEPTH_FROM_ID(id); - dp->alpha_sBIT = dp->blue_sBIT = dp->green_sBIT = dp->alpha_sBIT = - dp->bit_depth; - dp->interlace_type = INTERLACE_FROM_ID(id); - dp->id = id; - /* All the rest are filled in after the read_info: */ - dp->w = 0; - dp->h = 0; - dp->npasses = 0; - dp->pixel_size = 0; - dp->bit_width = 0; - dp->cbRow = 0; - dp->do_interlace = do_interlace; - dp->is_transparent = 0; - /* Preset the transparent color to black: */ - memset(&dp->transparent, 0, sizeof dp->transparent); - /* Preset the palette to full intensity/opaque througout: */ - memset(dp->palette, 0xff, sizeof dp->palette); - -} - -/* Call this only if the colour type is 3 - PNG_COLOR_TYPE_PALETTE - otherwise - * it will png_error out. The API returns true if tRNS information was - * present. - */ -static int -standard_palette_init(standard_palette palette, png_structp pp, png_infop pi) -{ - png_colorp pal; - png_bytep trans_alpha; - int num; - - pal = 0; - num = -1; - if (png_get_PLTE(pp, pi, &pal, &num) & PNG_INFO_PLTE) - { - int i; - - for (i=0; i<num; ++i) - { - palette[i].red = pal[i].red; - palette[i].green = pal[i].green; - palette[i].blue = pal[i].blue; - } - - /* Mark the remainder of the entries with a flag value: */ - for (; i<256; ++i) - palette[i].red = palette[i].green = palette[i].blue = 126; - } - - else /* !png_get_PLTE */ - png_error(pp, "validate: missing PLTE with color type 3"); - - trans_alpha = 0; - num = -1; - if (png_get_tRNS(pp, pi, &trans_alpha, &num, 0) & PNG_INFO_tRNS) - { - int i; - - /* Any of these are crash-worthy - given the implementation of - * png_get_tRNS up to 1.5 an app won't crash if it just checks the - * result above and fails to check that the variables it passed have - * actually been filled in! Note that if the app were to pass the - * last, png_color_16p, variable too it couldn't rely on this. - */ - if (trans_alpha == 0 || num <= 0 || num > 256) - png_error(pp, "validate: unexpected png_get_tRNS (palette) result"); - - for (i=0; i<num; ++i) - palette[i].alpha = trans_alpha[i]; - - for (; i<256; ++i) - palette[i].alpha = 255; - - return 1; /* transparency */ - } - - else - { - /* No transparency - just set the alpha channel to opaque. */ - int i; - - for (i=0; i<256; ++i) - palette[i].alpha = 255; - - return 0; /* no transparency */ - } -} - -/* By passing a 'standard_display' the progressive callbacks can be used - * directly by the sequential code, the functions suffixed "_imp" are the - * implementations, the functions without the suffix are the callbacks. - * - * The code for the info callback is split into two because this callback calls - * png_read_update_info or png_start_read_image and what gets called depends on - * whether the info needs updating (we want to test both calls in pngvalid.) - */ -static void -standard_info_part1(standard_display *dp, png_structp pp, png_infop pi) -{ - if (png_get_bit_depth(pp, pi) != dp->bit_depth) - png_error(pp, "validate: bit depth changed"); - - if (png_get_color_type(pp, pi) != dp->colour_type) - png_error(pp, "validate: color type changed"); - - if (png_get_filter_type(pp, pi) != PNG_FILTER_TYPE_BASE) - png_error(pp, "validate: filter type changed"); - - if (png_get_interlace_type(pp, pi) != dp->interlace_type) - png_error(pp, "validate: interlacing changed"); - - if (png_get_compression_type(pp, pi) != PNG_COMPRESSION_TYPE_BASE) - png_error(pp, "validate: compression type changed"); - - dp->w = png_get_image_width(pp, pi); - - if (dp->w != standard_width(pp, dp->id)) - png_error(pp, "validate: image width changed"); - - dp->h = png_get_image_height(pp, pi); - - if (dp->h != standard_height(pp, dp->id)) - png_error(pp, "validate: image height changed"); - - /* Record (but don't check at present) the input sBIT according to the colour - * type information. - */ - { - png_color_8p sBIT = 0; - - if (png_get_sBIT(pp, pi, &sBIT) & PNG_INFO_sBIT) - { - int sBIT_invalid = 0; - - if (sBIT == 0) - png_error(pp, "validate: unexpected png_get_sBIT result"); - - if (dp->colour_type & PNG_COLOR_MASK_COLOR) - { - if (sBIT->red == 0 || sBIT->red > dp->bit_depth) - sBIT_invalid = 1; - else - dp->red_sBIT = sBIT->red; - - if (sBIT->green == 0 || sBIT->green > dp->bit_depth) - sBIT_invalid = 1; - else - dp->green_sBIT = sBIT->green; - - if (sBIT->blue == 0 || sBIT->blue > dp->bit_depth) - sBIT_invalid = 1; - else - dp->blue_sBIT = sBIT->blue; - } - - else /* !COLOR */ - { - if (sBIT->gray == 0 || sBIT->gray > dp->bit_depth) - sBIT_invalid = 1; - else - dp->blue_sBIT = dp->green_sBIT = dp->red_sBIT = sBIT->gray; - } - - /* All 8 bits in tRNS for a palette image are significant - see the - * spec. - */ - if (dp->colour_type & PNG_COLOR_MASK_ALPHA) - { - if (sBIT->alpha == 0 || sBIT->alpha > dp->bit_depth) - sBIT_invalid = 1; - else - dp->alpha_sBIT = sBIT->alpha; - } - - if (sBIT_invalid) - png_error(pp, "validate: sBIT value out of range"); - } - } - - /* Important: this is validating the value *before* any transforms have been - * put in place. It doesn't matter for the standard tests, where there are - * no transforms, but it does for other tests where rowbytes may change after - * png_read_update_info. - */ - if (png_get_rowbytes(pp, pi) != standard_rowsize(pp, dp->id)) - png_error(pp, "validate: row size changed"); - - /* The palette is never read for non-palette images, even though it is valid - * - this could be changed. - */ - if (dp->colour_type == 3) /* palette */ - { - int i; - - dp->is_transparent = standard_palette_init(dp->palette, pp, pi); - - /* And validate the result. */ - for (i=0; i<256; ++i) - if (dp->palette[i].red != i || dp->palette[i].green != i || - dp->palette[i].blue != i) - png_error(pp, "validate: color type 3 PLTE chunk changed"); - } - - /* In any case always check for a tranparent color: */ - { - png_color_16p trans_color = 0; - - if (png_get_tRNS(pp, pi, 0, 0, &trans_color) & PNG_INFO_tRNS) - { - if (trans_color == 0) - png_error(pp, "validate: unexpected png_get_tRNS (color) result"); - - switch (dp->colour_type) - { - case 0: - dp->transparent.red = dp->transparent.green = dp->transparent.blue = - trans_color->gray; - dp->is_transparent = 1; - break; - - case 2: - dp->transparent.red = trans_color->red; - dp->transparent.green = trans_color->green; - dp->transparent.blue = trans_color->blue; - dp->is_transparent = 1; - break; - - case 3: - /* Not expected because it should result in the array case - * above. - */ - png_error(pp, "validate: unexpected png_get_tRNS result"); - break; - - default: - png_error(pp, "validate: invalid tRNS chunk with alpha image"); - } - } - } - - /* Read the number of passes - expected to match the value used when - * creating the image (interlaced or not). This has the side effect of - * turning on interlace handling (if do_interlace is not set.) - */ - dp->npasses = npasses_from_interlace_type(pp, dp->interlace_type); - if (!dp->do_interlace && dp->npasses != png_set_interlace_handling(pp)) - png_error(pp, "validate: file changed interlace type"); - - /* Caller calls png_read_update_info or png_start_read_image now, then calls - * part2. - */ -} - -/* This must be called *after* the png_read_update_info call to get the correct - * 'rowbytes' value, otherwise png_get_rowbytes will refer to the untransformed - * image. - */ -static void -standard_info_part2(standard_display *dp, png_structp pp, png_infop pi, - int nImages) -{ - /* Record cbRow now that it can be found. */ - dp->pixel_size = bit_size(pp, png_get_color_type(pp, pi), - png_get_bit_depth(pp, pi)); - dp->bit_width = png_get_image_width(pp, pi) * dp->pixel_size; - dp->cbRow = png_get_rowbytes(pp, pi); - - /* Validate the rowbytes here again. */ - if (dp->cbRow != (dp->bit_width+7)/8) - png_error(pp, "bad png_get_rowbytes calculation"); - - /* Then ensure there is enough space for the output image(s). */ - store_ensure_image(dp->ps, pp, nImages * dp->cbRow * dp->h); -} - -static void -standard_info_imp(standard_display *dp, png_structp pp, png_infop pi, - int nImages) -{ - /* Note that the validation routine has the side effect of turning on - * interlace handling in the subsequent code. - */ - standard_info_part1(dp, pp, pi); - - /* And the info callback has to call this (or png_read_update_info - see - * below in the png_modifier code for that variant. - */ - png_start_read_image(pp); - - /* Validate the height, width and rowbytes plus ensure that sufficient buffer - * exists for decoding the image. - */ - standard_info_part2(dp, pp, pi, nImages); -} - -static void -standard_info(png_structp pp, png_infop pi) -{ - standard_display *dp = png_get_progressive_ptr(pp); - - /* Call with nImages==1 because the progressive reader can only produce one - * image. - */ - standard_info_imp(dp, pp, pi, 1 /*only one image*/); -} - -static void -progressive_row(png_structp pp, png_bytep new_row, png_uint_32 y, int pass) -{ - PNG_CONST standard_display *dp = png_get_progressive_ptr(pp); - - /* When handling interlacing some rows will be absent in each pass, the - * callback still gets called, but with a NULL pointer. This is checked - * in the 'else' clause below. We need our own 'cbRow', but we can't call - * png_get_rowbytes because we got no info structure. - */ - if (new_row != NULL) - { - png_bytep row; - - /* In the case where the reader doesn't do the interlace it gives - * us the y in the sub-image: - */ - if (dp->do_interlace && dp->interlace_type == PNG_INTERLACE_ADAM7) - y = PNG_ROW_FROM_PASS_ROW(y, pass); - - /* Validate this just in case. */ - if (y >= dp->h) - png_error(pp, "invalid y to progressive row callback"); - - row = dp->ps->image + y * dp->cbRow; - - /* Combine the new row into the old: */ - if (dp->do_interlace) - { - if (dp->interlace_type == PNG_INTERLACE_ADAM7) - deinterlace_row(row, new_row, dp->pixel_size, dp->w, pass); - else - memcpy(row, new_row, dp->cbRow); - } - else - png_progressive_combine_row(pp, row, new_row); - } else if (dp->interlace_type == PNG_INTERLACE_ADAM7 && - PNG_ROW_IN_INTERLACE_PASS(y, pass) && - PNG_PASS_COLS(dp->w, pass) > 0) - png_error(pp, "missing row in progressive de-interlacing"); -} - -static void -sequential_row(standard_display *dp, png_structp pp, png_infop pi, - PNG_CONST png_bytep pImage, PNG_CONST png_bytep pDisplay) -{ - PNG_CONST int npasses = dp->npasses; - PNG_CONST int do_interlace = dp->do_interlace && - dp->interlace_type == PNG_INTERLACE_ADAM7; - PNG_CONST png_uint_32 height = standard_height(pp, dp->id); - PNG_CONST png_uint_32 width = standard_width(pp, dp->id); - PNG_CONST size_t cbRow = dp->cbRow; - int pass; - - for (pass=0; pass<npasses; ++pass) - { - png_uint_32 y; - png_uint_32 wPass = PNG_PASS_COLS(width, pass); - png_bytep pRow1 = pImage; - png_bytep pRow2 = pDisplay; - - for (y=0; y<height; ++y) - { - if (do_interlace) - { - /* wPass may be zero or this row may not be in this pass. - * png_read_row must not be called in either case. - */ - if (wPass > 0 && PNG_ROW_IN_INTERLACE_PASS(y, pass)) - { - /* Read the row into a pair of temporary buffers, then do the - * merge here into the output rows. - */ - png_byte row[STANDARD_ROWMAX], display[STANDARD_ROWMAX]; - - /* The following aids (to some extent) error detection - we can - * see where png_read_row wrote. Use opposite values in row and - * display to make this easier. - */ - memset(row, 0xff, sizeof row); - memset(display, 0, sizeof display); - - png_read_row(pp, row, display); - - if (pRow1 != NULL) - deinterlace_row(pRow1, row, dp->pixel_size, dp->w, pass); - - if (pRow2 != NULL) - deinterlace_row(pRow2, display, dp->pixel_size, dp->w, pass); - } - } - else - png_read_row(pp, pRow1, pRow2); - - if (pRow1 != NULL) - pRow1 += cbRow; - - if (pRow2 != NULL) - pRow2 += cbRow; - } - } - - /* And finish the read operation (only really necessary if the caller wants - * to find additional data in png_info from chunks after the last IDAT.) - */ - png_read_end(pp, pi); -} - -static void -standard_row_validate(standard_display *dp, png_structp pp, png_const_bytep row, - png_const_bytep display, png_uint_32 y) -{ - png_byte std[STANDARD_ROWMAX]; - - memset(std, 0xff, sizeof std); - standard_row(pp, std, dp->id, y); - - /* At the end both the 'row' and 'display' arrays should end up identical. - * In earlier passes 'row' will be partially filled in, with only the pixels - * that have been read so far, but 'display' will have those pixels - * replicated to fill the unread pixels while reading an interlaced image. - * The side effect inside the libpng sequential reader is that the 'row' - * array retains the correct values for unwritten pixels within the row - * bytes, while the 'display' array gets bits off the end of the image (in - * the last byte) trashed. Unfortunately in the progressive reader the - * row bytes are always trashed, so we always do a pixel_cmp here even though - * a memcmp of all cbRow bytes will succeed for the sequential reader. - */ - if (row != NULL && pixel_cmp(std, row, dp->bit_width) != 0) - { - char msg[64]; - sprintf(msg, "PNG image row %d changed", y); - png_error(pp, msg); - } - - /* In this case use pixel_cmp because we need to compare a partial - * byte at the end of the row if the row is not an exact multiple - * of 8 bits wide. - */ - if (display != NULL && pixel_cmp(std, display, dp->bit_width) != 0) - { - char msg[64]; - sprintf(msg, "display row %d changed", y); - png_error(pp, msg); - } -} - -static void -standard_image_validate(standard_display *dp, png_structp pp, - png_const_bytep pImage, png_const_bytep pDisplay) -{ - png_uint_32 y; - - for (y=0; y<dp->h; ++y) - { - standard_row_validate(dp, pp, pImage, pDisplay, y); - - if (pImage != NULL) - pImage += dp->cbRow; - - if (pDisplay != NULL) - pDisplay += dp->cbRow; - } - - /* This avoids false positives if the validation code is never called! */ - dp->ps->validated = 1; -} - -static void -standard_end(png_structp pp, png_infop pi) -{ - standard_display *dp = png_get_progressive_ptr(pp); - - UNUSED(pi) - - /* Validate the image - progressive reading only produces one variant for - * interlaced images. - */ - standard_image_validate(dp, pp, dp->ps->image, NULL); -} - -/* A single test run checking the standard image to ensure it is not damaged. */ -static void -standard_test(png_store* PNG_CONST psIn, png_uint_32 PNG_CONST id, - int do_interlace) -{ - standard_display d; - context(psIn, fault); - - /* Set up the display (stack frame) variables from the arguments to the - * function and initialize the locals that are filled in later. - */ - standard_display_init(&d, psIn, id, do_interlace); - - /* Everything is protected by a Try/Catch. The functions called also - * typically have local Try/Catch blocks. - */ - Try - { - png_structp pp; - png_infop pi; - - /* Get a png_struct for reading the image. This will throw an error if it - * fails, so we don't need to check the result. - */ - pp = set_store_for_read(d.ps, &pi, d.id, - d.do_interlace ? (d.ps->progressive ? - "pngvalid progressive deinterlacer" : - "pngvalid sequential deinterlacer") : (d.ps->progressive ? - "progressive reader" : "sequential reader")); - - /* Introduce the correct read function. */ - if (d.ps->progressive) - { - png_set_progressive_read_fn(pp, &d, standard_info, progressive_row, - standard_end); - - /* Now feed data into the reader until we reach the end: */ - store_progressive_read(d.ps, pp, pi); - } - else - { - /* Note that this takes the store, not the display. */ - png_set_read_fn(pp, d.ps, store_read); - - /* Check the header values: */ - png_read_info(pp, pi); - - /* The code tests both versions of the images that the sequential - * reader can produce. - */ - standard_info_imp(&d, pp, pi, 2 /*images*/); - - /* Need the total bytes in the image below; we can't get to this point - * unless the PNG file values have been checked against the expected - * values. - */ - { - PNG_CONST png_bytep pImage = d.ps->image; - PNG_CONST png_bytep pDisplay = pImage + d.cbRow * d.h; - - sequential_row(&d, pp, pi, pImage, pDisplay); - - /* After the last pass loop over the rows again to check that the - * image is correct. - */ - standard_image_validate(&d, pp, pImage, pDisplay); - } - } - - /* Check for validation. */ - if (!d.ps->validated) - png_error(pp, "image read failed silently"); - - /* Successful completion. */ - } - - Catch(fault) - d.ps = fault; /* make sure this hasn't been clobbered. */ - - /* In either case clean up the store. */ - store_read_reset(d.ps); -} - -static int -test_standard(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type, - int bdlo, int PNG_CONST bdhi) -{ - for (; bdlo <= bdhi; ++bdlo) - { - int interlace_type; - - for (interlace_type = PNG_INTERLACE_NONE; - interlace_type < PNG_INTERLACE_LAST; ++interlace_type) - { - standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), - interlace_type, 0, 0, 0), 0/*do_interlace*/); - - if (fail(pm)) - return 0; - } - } - - return 1; /* keep going */ -} - -static void -perform_standard_test(png_modifier *pm) -{ - /* Test each colour type over the valid range of bit depths (expressed as - * log2(bit_depth) in turn, stop as soon as any error is detected. - */ - if (!test_standard(pm, 0, 0, READ_BDHI)) - return; - - if (!test_standard(pm, 2, 3, READ_BDHI)) - return; - - if (!test_standard(pm, 3, 0, 3)) - return; - - if (!test_standard(pm, 4, 3, READ_BDHI)) - return; - - if (!test_standard(pm, 6, 3, READ_BDHI)) - return; -} - - -/********************************** SIZE TESTS ********************************/ -static int -test_size(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type, - int bdlo, int PNG_CONST bdhi) -{ - /* Run the tests on each combination. - * - * NOTE: on my 32 bit x86 each of the following blocks takes - * a total of 3.5 seconds if done across every combo of bit depth - * width and height. This is a waste of time in practice, hence the - * hinc and winc stuff: - */ - static PNG_CONST png_byte hinc[] = {1, 3, 11, 1, 5}; - static PNG_CONST png_byte winc[] = {1, 9, 5, 7, 1}; - for (; bdlo <= bdhi; ++bdlo) - { - png_uint_32 h, w; - - for (h=1; h<=16; h+=hinc[bdlo]) for (w=1; w<=16; w+=winc[bdlo]) - { - /* First test all the 'size' images against the sequential - * reader using libpng to deinterlace (where required.) This - * validates the write side of libpng. There are four possibilities - * to validate. - */ - standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), - PNG_INTERLACE_NONE, w, h, 0), 0/*do_interlace*/); - - if (fail(pm)) - return 0; - - standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), - PNG_INTERLACE_NONE, w, h, 1), 0/*do_interlace*/); - - if (fail(pm)) - return 0; - - standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), - PNG_INTERLACE_ADAM7, w, h, 0), 0/*do_interlace*/); - - if (fail(pm)) - return 0; - - standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), - PNG_INTERLACE_ADAM7, w, h, 1), 0/*do_interlace*/); - - if (fail(pm)) - return 0; - - /* Now validate the interlaced read side - do_interlace true, - * in the progressive case this does actually make a difference - * to the code used in the non-interlaced case too. - */ - standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), - PNG_INTERLACE_NONE, w, h, 0), 1/*do_interlace*/); - - if (fail(pm)) - return 0; - - standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), - PNG_INTERLACE_ADAM7, w, h, 0), 1/*do_interlace*/); - - if (fail(pm)) - return 0; - } - } - - return 1; /* keep going */ -} - -static void -perform_size_test(png_modifier *pm) -{ - /* Test each colour type over the valid range of bit depths (expressed as - * log2(bit_depth) in turn, stop as soon as any error is detected. - */ - if (!test_size(pm, 0, 0, READ_BDHI)) - return; - - if (!test_size(pm, 2, 3, READ_BDHI)) - return; - - /* For the moment don't do the palette test - it's a waste of time when - * compared to the greyscale test. - */ -#if 0 - if (!test_size(pm, 3, 0, 3)) - return; -#endif - - if (!test_size(pm, 4, 3, READ_BDHI)) - return; - - if (!test_size(pm, 6, 3, READ_BDHI)) - return; -} - - -/******************************* TRANSFORM TESTS ******************************/ -/* A set of tests to validate libpng image transforms. The possibilities here - * are legion because the transforms can be combined in a combinatorial - * fashion. To deal with this some measure of restraint is required, otherwise - * the tests would take forever. - */ -typedef struct image_pixel -{ - /* A local (pngvalid) representation of a PNG pixel, in all its - * various forms. - */ - unsigned int red, green, blue, alpha; /* For non-palette images. */ - unsigned int palette_index; /* For a palette image. */ - png_byte colour_type; /* As in the spec. */ - png_byte bit_depth; /* Defines bit size in row */ - png_byte sample_depth; /* Scale of samples */ - int have_tRNS; /* tRNS chunk may need processing */ - - /* For checking the code calculates double precision floating point values - * along with an error value, accumulated from the transforms. Because an - * sBIT setting allows larger error bounds (indeed, by the spec, apparently - * up to just less than +/-1 in the scaled value) the *lowest* sBIT for each - * channel is stored. This sBIT value is folded in to the stored error value - * at the end of the application of the transforms to the pixel. - */ - double redf, greenf, bluef, alphaf; - double rede, greene, bluee, alphae; - png_byte red_sBIT, green_sBIT, blue_sBIT, alpha_sBIT; -} image_pixel; - -/* Shared utility function, see below. */ -static void -image_pixel_setf(image_pixel *this, unsigned int max) -{ - this->redf = this->red / (double)max; - this->greenf = this->green / (double)max; - this->bluef = this->blue / (double)max; - this->alphaf = this->alpha / (double)max; - - if (this->red < max) - this->rede = this->redf * DBL_EPSILON; - else - this->rede = 0; - if (this->green < max) - this->greene = this->greenf * DBL_EPSILON; - else - this->greene = 0; - if (this->blue < max) - this->bluee = this->bluef * DBL_EPSILON; - else - this->bluee = 0; - if (this->alpha < max) - this->alphae = this->alphaf * DBL_EPSILON; - else - this->alphae = 0; -} - -/* Initialize the structure for the next pixel - call this before doing any - * transforms and call it for each pixel since all the fields may need to be - * reset. - */ -static void -image_pixel_init(image_pixel *this, png_const_bytep row, png_byte colour_type, - png_byte bit_depth, png_uint_32 x, standard_palette palette) -{ - PNG_CONST png_byte sample_depth = (png_byte)(colour_type == - PNG_COLOR_TYPE_PALETTE ? 8 : bit_depth); - PNG_CONST unsigned int max = (1U<<sample_depth)-1; - - /* Initially just set everything to the same number and the alpha to opaque. - * Note that this currently assumes a simple palette where entry x has colour - * rgb(x,x,x)! - */ - this->palette_index = this->red = this->green = this->blue = - sample(row, colour_type, bit_depth, x, 0); - this->alpha = max; - this->red_sBIT = this->green_sBIT = this->blue_sBIT = this->alpha_sBIT = - sample_depth; - - /* Then override as appropriate: */ - if (colour_type == 3) /* palette */ - { - /* This permits the caller to default to the sample value. */ - if (palette != 0) - { - PNG_CONST unsigned int i = this->palette_index; - - this->red = palette[i].red; - this->green = palette[i].green; - this->blue = palette[i].blue; - this->alpha = palette[i].alpha; - } - } - - else /* not palette */ - { - unsigned int i = 0; - - if (colour_type & 2) - { - this->green = sample(row, colour_type, bit_depth, x, 1); - this->blue = sample(row, colour_type, bit_depth, x, 2); - i = 2; - } - if (colour_type & 4) - this->alpha = sample(row, colour_type, bit_depth, x, ++i); - } - - /* Calculate the scaled values, these are simply the values divided by - * 'max' and the error is initialized to the double precision epsilon value - * from the header file. - */ - image_pixel_setf(this, max); - - /* Store the input information for use in the transforms - these will - * modify the information. - */ - this->colour_type = colour_type; - this->bit_depth = bit_depth; - this->sample_depth = sample_depth; - this->have_tRNS = 0; -} - -/* Convert a palette image to an rgb image. This necessarily converts the tRNS - * chunk at the same time, because the tRNS will be in palette form. - */ -static void -image_pixel_convert_PLTE(image_pixel *this, const standard_display *display) -{ - if (this->colour_type == PNG_COLOR_TYPE_PALETTE) - { - PNG_CONST unsigned int i = this->palette_index; - - this->bit_depth = this->sample_depth; - this->red = display->palette[i].red; - this->green = display->palette[i].green; - this->blue = display->palette[i].blue; - this->red_sBIT = display->red_sBIT; - this->green_sBIT = display->green_sBIT; - this->blue_sBIT = display->blue_sBIT; - - if (this->have_tRNS) - { - this->alpha = display->palette[i].alpha; - this->colour_type = PNG_COLOR_TYPE_RGB_ALPHA; - this->have_tRNS = 0; - } - else - { - this->alpha = 255; - this->colour_type = PNG_COLOR_TYPE_RGB; - } - this->alpha_sBIT = 8; - - /* And regenerate the scaled values and all the errors, which are now set - * back to the initial values. - */ - image_pixel_setf(this, 255); - } -} - -/* Add an alpha channel, this will glom in the tRNS information because tRNS is - * not valid in an alpha image. The bit depth will invariably be set to at - * least 8. Palette images will be converted to alpha (using the above API). - */ -static void -image_pixel_add_alpha(image_pixel *this, const standard_display *display) -{ - if (this->colour_type == PNG_COLOR_TYPE_PALETTE) - image_pixel_convert_PLTE(this, display); - - if ((this->colour_type & PNG_COLOR_MASK_ALPHA) == 0) - { - if (this->colour_type == PNG_COLOR_TYPE_GRAY) - { - if (this->bit_depth < 8) - this->bit_depth = 8; - - if (this->have_tRNS) - { - this->have_tRNS = 0; - - /* Check the input, original, channel value here against the - * original tRNS gray chunk valie. - */ - if (this->red == display->transparent.red) - this->alphaf = 0; - else - this->alphaf = 1; - } - else - this->alphaf = 1; - - this->colour_type = PNG_COLOR_TYPE_GRAY_ALPHA; - } - - else if (this->colour_type == PNG_COLOR_TYPE_RGB) - { - if (this->have_tRNS) - { - this->have_tRNS = 0; - - /* Again, check the exact input values, not the current transformed - * value! - */ - if (this->red == display->transparent.red && - this->green == display->transparent.green && - this->blue == display->transparent.blue) - this->alphaf = 0; - else - this->alphaf = 1; - - this->colour_type = PNG_COLOR_TYPE_RGB_ALPHA; - } - } - - /* The error in the alpha is zero and the sBIT value comes from the - * original sBIT data (actually it will always be the original bit depth). - */ - this->alphae = 0; - this->alpha_sBIT = display->alpha_sBIT; - } -} - -struct transform_display; -typedef struct image_transform -{ - /* The name of this transform: a string. */ - PNG_CONST char *name; - - /* Each transform can be disabled from the command line: */ - int enable; - - /* The global list of transforms; read only. */ - struct image_transform *PNG_CONST list; - - /* The global count of the number of times this transform has been set on an - * image. - */ - unsigned int global_use; - - /* The local count of the number of times this transform has been set. */ - unsigned int local_use; - - /* The next transform in the list, each transform must call its own next - * transform after it has processed the pixel successfully. - */ - PNG_CONST struct image_transform *next; - - /* A single transform for the image, expressed as a series of function - * callbacks and some space for values. - * - * First a callback to set the transform on the current png_read_struct: - */ - void (*set)(PNG_CONST struct image_transform *this, - struct transform_display *that, png_structp pp, png_infop pi); - - /* Then a transform that takes an input pixel in one PNG format or another - * and modifies it by a pngvalid implementation of the transform (thus - * duplicating the libpng intent without, we hope, duplicating the bugs - * in the libpng implementation!) The png_structp is solely to allow error - * reporting via png_error and png_warning. - */ - void (*mod)(PNG_CONST struct image_transform *this, image_pixel *that, - png_structp pp, PNG_CONST struct transform_display *display); - - /* Add this transform to the list and return true if the transform is - * meaningful for this colour type and bit depth - if false then the - * transform should have no effect on the image so there's not a lot of - * point running it. - */ - int (*add)(struct image_transform *this, - PNG_CONST struct image_transform **that, png_byte colour_type, - png_byte bit_depth); -} image_transform; - -typedef struct transform_display -{ - standard_display this; - - /* Parameters */ - png_modifier* pm; - PNG_CONST image_transform* transform_list; - - /* Local variables */ - png_byte output_colour_type; - png_byte output_bit_depth; -} transform_display; - -/* Two functions to end the list: */ -static void -image_transform_set_end(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - UNUSED(this) - UNUSED(that) - UNUSED(pp) - UNUSED(pi) -} - -/* At the end of the list recalculate the output image pixel value from the - * double precision values set up by the preceding 'mod' calls: - */ -static unsigned int -sample_scale(double sample_value, unsigned int scale) -{ - sample_value = floor(sample_value * scale + .5); - - /* Return NaN as 0: */ - if (!(sample_value > 0)) - sample_value = 0; - else if (sample_value > scale) - sample_value = scale; - - return (unsigned int)sample_value; -} - -static void -image_transform_mod_end(PNG_CONST image_transform *this, image_pixel *that, - png_structp pp, PNG_CONST transform_display *display) -{ - PNG_CONST unsigned int scale = (1U<<that->sample_depth)-1; - - UNUSED(this) - UNUSED(pp) - UNUSED(display) - - /* At the end recalculate the digitized red green and blue values according - * to the current sample_depth of the pixel. - * - * The sample value is simply scaled to the maximum, checking for over - * and underflow (which can both happen for some image transforms, - * including simple size scaling, though libpng doesn't do that at present. - */ - that->red = sample_scale(that->redf, scale); - - /* The error value is increased, at the end, according to the lowest sBIT - * value seen. Common sense tells us that the intermediate integer - * representations are no more accurate than +/- 0.5 in the integral values, - * the sBIT allows the implementation to be worse than this. In addition the - * PNG specification actually permits any error within the range (-1..+1), - * but that is ignored here. Instead the final digitized value is compared, - * below to the digitized value of the error limits - this has the net effect - * of allowing (almost) +/-1 in the output value. It's difficult to see how - * any algorithm that digitizes intermediate results can be more accurate. - */ - that->rede += 1./(2*((1U<<that->red_sBIT)-1)); - - if (that->colour_type & PNG_COLOR_MASK_COLOR) - { - that->green = sample_scale(that->greenf, scale); - that->blue = sample_scale(that->bluef, scale); - that->greene += 1./(2*((1U<<that->green_sBIT)-1)); - that->bluee += 1./(2*((1U<<that->blue_sBIT)-1)); - } - else - { - that->blue = that->green = that->red; - that->bluef = that->greenf = that->redf; - that->bluee = that->greene = that->rede; - } - - if ((that->colour_type & PNG_COLOR_MASK_ALPHA) || - that->colour_type == PNG_COLOR_TYPE_PALETTE) - { - that->alpha = sample_scale(that->alphaf, scale); - that->alphae += 1./(2*((1U<<that->alpha_sBIT)-1)); - } - else - { - that->alpha = scale; /* opaque */ - that->alpha = 1; /* Override this. */ - that->alphae = 0; /* It's exact ;-) */ - } -} - -/* Static 'end' structure: */ -static image_transform image_transform_end = -{ - "(end)", /* name */ - 1, /* enable */ - 0, /* list */ - 0, /* global_use */ - 0, /* local_use */ - 0, /* next */ - image_transform_set_end, - image_transform_mod_end, - 0 /* never called, I want it to crash if it is! */ -}; - -/* Reader callbacks and implementations, where they differ from the standard - * ones. - */ -static void -transform_display_init(transform_display *dp, png_modifier *pm, png_uint_32 id, - PNG_CONST image_transform *transform_list) -{ - /* Standard fields */ - standard_display_init(&dp->this, &pm->this, id, 0/*do_interlace*/); - - /* Parameter fields */ - dp->pm = pm; - dp->transform_list = transform_list; - - /* Local variable fields */ - dp->output_colour_type = 255; /* invalid */ - dp->output_bit_depth = 255; /* invalid */ -} - -static void -transform_info_imp(transform_display *dp, png_structp pp, png_infop pi) -{ - /* Reuse the standard stuff as appropriate. */ - standard_info_part1(&dp->this, pp, pi); - - /* Now set the list of transforms. */ - dp->transform_list->set(dp->transform_list, dp, pp, pi); - - /* Update the info structure for these transforms: */ - png_read_update_info(pp, pi); - - /* And get the output information into the standard_display */ - standard_info_part2(&dp->this, pp, pi, 1/*images*/); - - /* Plus the extra stuff we need for the transform tests: */ - dp->output_colour_type = png_get_color_type(pp, pi); - dp->output_bit_depth = png_get_bit_depth(pp, pi); - - /* Validate the combination of colour type and bit depth that we are getting - * out of libpng; the semantics of something not in the PNG spec are, at - * best, unclear. - */ - switch (dp->output_colour_type) - { - case PNG_COLOR_TYPE_PALETTE: - if (dp->output_bit_depth > 8) goto error; - /*FALL THROUGH*/ - case PNG_COLOR_TYPE_GRAY: - if (dp->output_bit_depth == 1 || dp->output_bit_depth == 2 || - dp->output_bit_depth == 4) - break; - /*FALL THROUGH*/ - default: - if (dp->output_bit_depth == 8 || dp->output_bit_depth == 16) - break; - /*FALL THROUGH*/ - error: - { - char message[128]; - size_t pos; - - pos = safecat(message, sizeof message, 0, - "invalid final bit depth: colour type("); - pos = safecatn(message, sizeof message, pos, dp->output_colour_type); - pos = safecat(message, sizeof message, pos, ") with bit depth: "); - pos = safecatn(message, sizeof message, pos, dp->output_bit_depth); - - png_error(pp, message); - } - } - - /* Use a test pixel to check that the output agrees with what we expect - - * this avoids running the whole test if the output is unexpected. - */ - { - image_pixel test_pixel; - - memset(&test_pixel, 0, sizeof test_pixel); - test_pixel.colour_type = dp->this.colour_type; /* input */ - test_pixel.bit_depth = dp->this.bit_depth; - if (test_pixel.colour_type == PNG_COLOR_TYPE_PALETTE) - test_pixel.sample_depth = 8; - else - test_pixel.sample_depth = test_pixel.bit_depth; - /* Don't need sBIT here */ - test_pixel.have_tRNS = dp->this.is_transparent; - - dp->transform_list->mod(dp->transform_list, &test_pixel, pp, dp); - - if (test_pixel.colour_type != dp->output_colour_type) - { - char message[128]; - size_t pos = safecat(message, sizeof message, 0, "colour type "); - - pos = safecatn(message, sizeof message, pos, dp->output_colour_type); - pos = safecat(message, sizeof message, pos, " expected "); - pos = safecatn(message, sizeof message, pos, test_pixel.colour_type); - - png_error(pp, message); - } - - if (test_pixel.bit_depth != dp->output_bit_depth) - { - char message[128]; - size_t pos = safecat(message, sizeof message, 0, "bit depth "); - - pos = safecatn(message, sizeof message, pos, dp->output_bit_depth); - pos = safecat(message, sizeof message, pos, " expected "); - pos = safecatn(message, sizeof message, pos, test_pixel.bit_depth); - - png_error(pp, message); - } - - /* If both bit depth and colour type are correct check the sample depth. - * I believe these are both internal errors. - */ - if (test_pixel.colour_type == PNG_COLOR_TYPE_PALETTE) - { - if (test_pixel.sample_depth != 8) /* oops - internal error! */ - png_error(pp, "pngvalid: internal: palette sample depth not 8"); - } - else if (test_pixel.sample_depth != dp->output_bit_depth) - { - char message[128]; - size_t pos = safecat(message, sizeof message, 0, - "internal: sample depth "); - - pos = safecatn(message, sizeof message, pos, dp->output_bit_depth); - pos = safecat(message, sizeof message, pos, " expected "); - pos = safecatn(message, sizeof message, pos, test_pixel.sample_depth); - - png_error(pp, message); - } - } -} - -static void -transform_info(png_structp pp, png_infop pi) -{ - transform_info_imp(png_get_progressive_ptr(pp), pp, pi); -} - -static void -transform_range_check(png_structp pp, unsigned int r, unsigned int g, - unsigned int b, unsigned int a, unsigned int in_digitized, double in, - unsigned int out, png_byte sample_depth, double err, PNG_CONST char *name) -{ - /* Compare the scaled, digitzed, values of our local calculation (in+-err) - * with the digitized values libpng produced; 'sample_depth' is the actual - * digitization depth of the libpng output colors (the bit depth except for - * palette images where it is always 8.) - */ - unsigned int max = (1U<<sample_depth)-1; - double in_min = ceil((in-err)*max - .5); - double in_max = floor((in+err)*max + .5); - if (!(out >= in_min && out <= in_max)) - { - char message[256]; - size_t pos; - - pos = safecat(message, sizeof message, 0, name); - pos = safecat(message, sizeof message, pos, " output value error: rgba("); - pos = safecatn(message, sizeof message, pos, r); - pos = safecat(message, sizeof message, pos, ","); - pos = safecatn(message, sizeof message, pos, g); - pos = safecat(message, sizeof message, pos, ","); - pos = safecatn(message, sizeof message, pos, b); - pos = safecat(message, sizeof message, pos, ","); - pos = safecatn(message, sizeof message, pos, a); - pos = safecat(message, sizeof message, pos, "): "); - pos = safecatn(message, sizeof message, pos, out); - pos = safecat(message, sizeof message, pos, " expected: "); - pos = safecatn(message, sizeof message, pos, in_digitized); - pos = safecat(message, sizeof message, pos, " ("); - pos = safecatd(message, sizeof message, pos, (in-err)*max, 3); - pos = safecat(message, sizeof message, pos, ".."); - pos = safecatd(message, sizeof message, pos, (in+err)*max, 3); - pos = safecat(message, sizeof message, pos, ")"); - - png_error(pp, message); - } -} - -static void -transform_image_validate(transform_display *dp, png_structp pp, png_infop pi, - png_const_bytep pRow) -{ - /* Constants for the loop below: */ - PNG_CONST png_byte in_ct = dp->this.colour_type; - PNG_CONST png_byte in_bd = dp->this.bit_depth; - PNG_CONST png_uint_32 w = dp->this.w; - PNG_CONST png_uint_32 h = dp->this.h; - PNG_CONST size_t cbRow = dp->this.cbRow; - PNG_CONST png_byte out_ct = dp->output_colour_type; - PNG_CONST png_byte out_bd = dp->output_bit_depth; - PNG_CONST png_byte sample_depth = (png_byte)(out_ct == - PNG_COLOR_TYPE_PALETTE ? 8 : out_bd); - PNG_CONST png_byte red_sBIT = dp->this.red_sBIT; - PNG_CONST png_byte green_sBIT = dp->this.green_sBIT; - PNG_CONST png_byte blue_sBIT = dp->this.blue_sBIT; - PNG_CONST png_byte alpha_sBIT = dp->this.alpha_sBIT; - PNG_CONST int have_tRNS = dp->this.is_transparent; - - standard_palette out_palette; - png_uint_32 y; - - UNUSED(pi) - - /* Read the palette corresponding to the output if the output colour type - * indicates a palette, othewise set out_palette to garbage. - */ - if (out_ct == PNG_COLOR_TYPE_PALETTE) - (void)standard_palette_init(out_palette, pp, pi); - else - memset(out_palette, 0x5e, sizeof out_palette); - - for (y=0; y<h; ++y, pRow += cbRow) - { - png_uint_32 x; - - /* The original, standard, row pre-transforms. */ - png_byte std[STANDARD_ROWMAX]; - - transform_row(pp, std, in_ct, in_bd, y); - - /* Go through each original pixel transforming it and comparing with what - * libpng did to the same pixel. - */ - for (x=0; x<w; ++x) - { - image_pixel in_pixel, out_pixel; - unsigned int r, g, b, a; - - /* Find out what we think the pixel should be: */ - image_pixel_init(&in_pixel, std, in_ct, in_bd, x, dp->this.palette); - - in_pixel.red_sBIT = red_sBIT; - in_pixel.green_sBIT = green_sBIT; - in_pixel.blue_sBIT = blue_sBIT; - in_pixel.alpha_sBIT = alpha_sBIT; - in_pixel.have_tRNS = have_tRNS; - - /* For error detection, below. */ - r = in_pixel.red; - g = in_pixel.green; - b = in_pixel.blue; - a = in_pixel.alpha; - - dp->transform_list->mod(dp->transform_list, &in_pixel, pp, dp); - - /* Read the output pixel and compare it to what we got, we don't - * use the error field here, so no need to update sBIT. - */ - image_pixel_init(&out_pixel, pRow, out_ct, out_bd, x, out_palette); - - /* We don't expect changes to the index here even if the bit depth is - * changed. - */ - if (in_ct == PNG_COLOR_TYPE_PALETTE && - out_ct == PNG_COLOR_TYPE_PALETTE) - { - if (in_pixel.palette_index != out_pixel.palette_index) - png_error(pp, "unexpected transformed palette index"); - } - - /* Check the colours for palette images too - in fact the palette could - * be separately verified itself in most cases. - */ - if (in_pixel.red != out_pixel.red) - transform_range_check(pp, r, g, b, a, in_pixel.red, in_pixel.redf, - out_pixel.red, sample_depth, in_pixel.rede, "red/gray"); - - if ((out_ct & PNG_COLOR_MASK_COLOR) != 0 && - in_pixel.green != out_pixel.green) - transform_range_check(pp, r, g, b, a, in_pixel.green, - in_pixel.greenf, out_pixel.green, sample_depth, in_pixel.greene, - "green"); - - if ((out_ct & PNG_COLOR_MASK_COLOR) != 0 && - in_pixel.blue != out_pixel.blue) - transform_range_check(pp, r, g, b, a, in_pixel.blue, in_pixel.bluef, - out_pixel.blue, sample_depth, in_pixel.bluee, "blue"); - - if ((out_ct & PNG_COLOR_MASK_ALPHA) != 0 && - in_pixel.alpha != out_pixel.alpha) - transform_range_check(pp, r, g, b, a, in_pixel.alpha, - in_pixel.alphaf, out_pixel.alpha, sample_depth, in_pixel.alphae, - "alpha"); - } /* pixel (x) loop */ - } /* row (y) loop */ - - /* Record that something was actually checked to avoid a false positive. */ - dp->this.ps->validated = 1; -} - -static void -transform_end(png_structp pp, png_infop pi) -{ - transform_display *dp = png_get_progressive_ptr(pp); - - transform_image_validate(dp, pp, pi, dp->this.ps->image); -} - -/* A single test run. */ -static void -transform_test(png_modifier *pmIn, PNG_CONST png_uint_32 idIn, - PNG_CONST image_transform* transform_listIn, PNG_CONST char *name) -{ - transform_display d; - context(&pmIn->this, fault); - - transform_display_init(&d, pmIn, idIn, transform_listIn); - - Try - { - png_structp pp; - png_infop pi; - - /* Get a png_struct for writing the image. */ - pp = set_modifier_for_read(d.pm, &pi, d.this.id, name); - -# if 0 - /* Logging (debugging only) */ - { - char buffer[256]; - - (void)store_message(&d.pm->this, pp, buffer, sizeof buffer, 0, - "running test"); - - fprintf(stderr, "%s\n", buffer); - } -# endif - - /* Introduce the correct read function. */ - if (d.pm->this.progressive) - { - /* Share the row function with the standard implementation. */ - png_set_progressive_read_fn(pp, &d, transform_info, progressive_row, - transform_end); - - /* Now feed data into the reader until we reach the end: */ - modifier_progressive_read(d.pm, pp, pi); - } - else - { - /* modifier_read expects a png_modifier* */ - png_set_read_fn(pp, d.pm, modifier_read); - - /* Check the header values: */ - png_read_info(pp, pi); - - /* Process the 'info' requirements. Only one image is generated */ - transform_info_imp(&d, pp, pi); - - sequential_row(&d.this, pp, pi, NULL, d.this.ps->image); - - transform_image_validate(&d, pp, pi, d.this.ps->image); - } - - modifier_reset(d.pm); - } - - Catch(fault) - modifier_reset((png_modifier*)fault); -} - -/* The transforms: */ -#define ITSTRUCT(name) image_transform_##name -#define IT(name,prev)\ -static image_transform ITSTRUCT(name) =\ -{\ - #name,\ - 1, /*enable*/\ - &ITSTRUCT(prev), /*list*/\ - 0, /*global_use*/\ - 0, /*local_use*/\ - 0, /*next*/\ - image_transform_png_set_##name##_set,\ - image_transform_png_set_##name##_mod,\ - image_transform_png_set_##name##_add\ -} - -/* To save code: */ -static int -image_transform_default_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - UNUSED(colour_type) - UNUSED(bit_depth) - - this->next = *that; - *that = this; - - return 1; -} - -/* png_set_palette_to_rgb */ -static void -image_transform_png_set_palette_to_rgb_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - png_set_palette_to_rgb(pp); - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_palette_to_rgb_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - if (that->colour_type == PNG_COLOR_TYPE_PALETTE) - image_pixel_convert_PLTE(that, &display->this); - - this->next->mod(this->next, that, pp, display); -} - -static int -image_transform_png_set_palette_to_rgb_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - UNUSED(bit_depth) - - this->next = *that; - *that = this; - - return colour_type == PNG_COLOR_TYPE_PALETTE; -} - -IT(palette_to_rgb, end); - - -/* png_set_tRNS_to_alpha */ -static void -image_transform_png_set_tRNS_to_alpha_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - png_set_tRNS_to_alpha(pp); - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_tRNS_to_alpha_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - /* LIBPNG BUG: this always forces palette images to RGB. */ - if (that->colour_type == PNG_COLOR_TYPE_PALETTE) - image_pixel_convert_PLTE(that, &display->this); - - /* This effectively does an 'expand' only if there is some transparency to - * covert to an alpha channel. - */ - if (that->have_tRNS) - image_pixel_add_alpha(that, &display->this); - - /* LIBPNG BUG: otherwise libpng still expands to 8 bits! */ - else - { - if (that->bit_depth < 8) - that->bit_depth =8; - if (that->sample_depth < 8) - that->sample_depth = 8; - } - - this->next->mod(this->next, that, pp, display); -} - -static int -image_transform_png_set_tRNS_to_alpha_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - UNUSED(bit_depth) - - this->next = *that; - *that = this; - - /* We don't know yet whether there will be a tRNS chunk, but we know that - * this transformation should do nothing if there already is an alpha - * channel. - */ - return (colour_type & PNG_COLOR_MASK_ALPHA) == 0; -} - -IT(tRNS_to_alpha,palette_to_rgb); - -/* png_set_gray_to_rgb */ -static void -image_transform_png_set_gray_to_rgb_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - png_set_gray_to_rgb(pp); - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_gray_to_rgb_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - /* NOTE: we can actually pend the tRNS processing at this point because we - * can correctly recognize the original pixel value even though we have - * mapped the one gray channel to the three RGB ones, but in fact libpng - * doesn't do this, so we don't either. - */ - if ((that->colour_type & PNG_COLOR_MASK_COLOR) == 0 && that->have_tRNS) - image_pixel_add_alpha(that, &display->this); - - /* Simply expand the bit depth and alter the colour type as required. */ - if (that->colour_type == PNG_COLOR_TYPE_GRAY) - { - /* RGB images have a bit depth at least equal to '8' */ - if (that->bit_depth < 8) - that->sample_depth = that->bit_depth = 8; - - /* And just changing the colour type works here because the green and blue - * channels are being maintained in lock-step with the red/gray: - */ - that->colour_type = PNG_COLOR_TYPE_RGB; - } - - else if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA) - that->colour_type = PNG_COLOR_TYPE_RGB_ALPHA; - - this->next->mod(this->next, that, pp, display); -} - -static int -image_transform_png_set_gray_to_rgb_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - UNUSED(bit_depth) - - this->next = *that; - *that = this; - - return (colour_type & PNG_COLOR_MASK_COLOR) == 0; -} - -IT(gray_to_rgb,tRNS_to_alpha); - -/* png_set_expand */ -static void -image_transform_png_set_expand_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - png_set_expand(pp); - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_expand_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - /* The general expand case depends on what the colour type is: */ - if (that->colour_type == PNG_COLOR_TYPE_PALETTE) - image_pixel_convert_PLTE(that, &display->this); - else if (that->bit_depth < 8) /* grayscale */ - that->sample_depth = that->bit_depth = 8; - - if (that->have_tRNS) - image_pixel_add_alpha(that, &display->this); - - this->next->mod(this->next, that, pp, display); -} - -static int -image_transform_png_set_expand_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - UNUSED(bit_depth) - - this->next = *that; - *that = this; - - /* 'expand' should do nothing for RGBA or GA input - no tRNS and the bit - * depth is at least 8 already. - */ - return (colour_type & PNG_COLOR_MASK_ALPHA) == 0; -} - -IT(expand,gray_to_rgb); - -/* png_set_expand_gray_1_2_4_to_8 - * LIBPNG BUG: this just does an 'expand' - */ -static void -image_transform_png_set_expand_gray_1_2_4_to_8_set( - PNG_CONST image_transform *this, transform_display *that, png_structp pp, - png_infop pi) -{ - png_set_expand_gray_1_2_4_to_8(pp); - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_expand_gray_1_2_4_to_8_mod( - PNG_CONST image_transform *this, image_pixel *that, png_structp pp, - PNG_CONST transform_display *display) -{ - image_transform_png_set_expand_mod(this, that, pp, display); -} - -static int -image_transform_png_set_expand_gray_1_2_4_to_8_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - return image_transform_png_set_expand_add(this, that, colour_type, - bit_depth); -} - -IT(expand_gray_1_2_4_to_8, expand); - -/* png_set_strip_16 */ -static void -image_transform_png_set_strip_16_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - png_set_strip_16(pp); - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_strip_16_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - if (that->bit_depth == 16) - { - that->sample_depth = that->bit_depth = 8; - if (that->red_sBIT > 8) that->red_sBIT = 8; - if (that->green_sBIT > 8) that->green_sBIT = 8; - if (that->blue_sBIT > 8) that->blue_sBIT = 8; - if (that->alpha_sBIT > 8) that->alpha_sBIT = 8; - -# ifndef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED - /* The strip 16 algoirithm drops the low 8 bits rather than calculating - * 1/257, so we need to adjust the permitted errors appropriately: - */ - { - PNG_CONST double d = (255-128.5)/65535; - that->rede += d; - that->greene += d; - that->bluee += d; - that->alphae += d; - } -# endif - } - - this->next->mod(this->next, that, pp, display); -} - -static int -image_transform_png_set_strip_16_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - UNUSED(colour_type) - - this->next = *that; - *that = this; - - return bit_depth > 8; -} - -IT(strip_16, expand_gray_1_2_4_to_8); - -/* png_set_strip_alpha */ -static void -image_transform_png_set_strip_alpha_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - png_set_strip_alpha(pp); - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_strip_alpha_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA) - that->colour_type = PNG_COLOR_TYPE_GRAY; - else if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA) - that->colour_type = PNG_COLOR_TYPE_RGB; - - that->have_tRNS = 0; - that->alphaf = 1; - that->alphae = 0; - - this->next->mod(this->next, that, pp, display); -} - -static int -image_transform_png_set_strip_alpha_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - UNUSED(bit_depth) - - this->next = *that; - *that = this; - - return (colour_type & PNG_COLOR_MASK_ALPHA) != 0; -} - -IT(strip_alpha,strip_16); - -/* png_set_rgb_to_gray(png_structp, int err_action, double red, double green) - * png_set_rgb_to_gray_fixed(png_structp, int err_action, png_fixed_point red, - * png_fixed_point green) - * png_get_rgb_to_gray_status - * - * At present the APIs are simply tested using the 16.16 fixed point conversion - * values known to be used inside libpng: - * - * red: 6968 - * green: 23434 - * blue: 2366 - * - * NOTE: this currently ignores the gamma because no gamma is being set, the - * tests on gamma need to happen in the gamma test set. - */ -static void -image_transform_png_set_rgb_to_gray_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - PNG_CONST int error_action = 1; /* no error, no defines in png.h */ - -# ifdef PNG_FLOATING_POINT_SUPPORTED - png_set_rgb_to_gray(pp, error_action, -1, -1); -# else - png_set_rgb_to_gray_fixed(pp, error_action, -1, -1); -# endif - - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - if ((that->colour_type & PNG_COLOR_MASK_COLOR) != 0) - { - if (that->colour_type == PNG_COLOR_TYPE_PALETTE) - image_pixel_convert_PLTE(that, &display->this); - - /* Image now has RGB channels... */ - that->bluef = that->greenf = that->redf = (that->redf * 6968 + - that->greenf * 23434 + that->bluef * 2366) / 32768; - that->bluee = that->greene = that->rede = (that->rede * 6968 + - that->greene * 23434 + that->bluee * 2366) / 32768 * - (1 + DBL_EPSILON * 6); - - /* The sBIT is the minium of the three colour channel sBITs. */ - if (that->red_sBIT > that->green_sBIT) - that->red_sBIT = that->green_sBIT; - if (that->red_sBIT > that->blue_sBIT) - that->red_sBIT = that->blue_sBIT; - that->blue_sBIT = that->green_sBIT = that->red_sBIT; - - /* And zap the colour bit in the type: */ - if (that->colour_type == PNG_COLOR_TYPE_RGB) - that->colour_type = PNG_COLOR_TYPE_GRAY; - else if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA) - that->colour_type = PNG_COLOR_TYPE_GRAY_ALPHA; - } - - this->next->mod(this->next, that, pp, display); -} - -static int -image_transform_png_set_rgb_to_gray_add(image_transform *this, - PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) -{ - UNUSED(bit_depth) - - this->next = *that; - *that = this; - - return (colour_type & PNG_COLOR_MASK_COLOR) != 0; -} - -IT(rgb_to_gray,strip_alpha); - -/* png_set_background(png_structp, png_const_color_16p background_color, - * int background_gamma_code, int need_expand, double background_gamma) - * png_set_background_fixed(png_structp, png_const_color_16p background_color, - * int background_gamma_code, int need_expand, - * png_fixed_point background_gamma) - * - * As with rgb_to_gray this ignores the gamma. -*/ -static void -image_transform_png_set_background_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - png_color_16 back; - - /* Since we don't know the output bit depth at this point we must use the - * input values and ask libpng to expand the chunk as required. - */ - back.index = 255; /* Should not be used */ - back.gray = back.blue = back.green = back.red = - (png_uint_16)((1U << that->this.bit_depth) >> 1); - -# ifdef PNG_FLOATING_POINT_SUPPORTED - png_set_background(pp, &back, PNG_BACKGROUND_GAMMA_FILE, 1, 0); -# else - png_set_background_fixed(pp, &back, PNG_BACKGROUND_GAMMA_FILE, 1, 0); -# endif - - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_background_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - /* Check for tRNS first: */ - if (that->have_tRNS && that->colour_type != PNG_COLOR_TYPE_PALETTE) - image_pixel_add_alpha(that, &display->this); - - /* This is only necessary if the alpha value is less than 1. */ - if (that->alphaf < 1) - { - /* Repeat the calculation above and scale the result: */ - unsigned int tmp = (1U << display->this.bit_depth); - double component = (tmp >> 1)/(double)(tmp-1); - - /* Now we do the background calculation without any gamma correction. */ - if (that->alphaf <= 0) - { - that->bluef = that->greenf = that->redf = component; - that->bluee = that->greene = that->rede = component * DBL_EPSILON; - that->blue_sBIT = that->green_sBIT = that->red_sBIT = that->bit_depth; - } - - else - { - component *= 1-that->alphaf; - that->redf = that->redf * that->alphaf + component; - that->rede = that->rede * that->alphaf + that->redf * 3 * DBL_EPSILON; - that->greenf = that->greenf * that->alphaf + component; - that->greene = that->greene * that->alphaf + that->greenf * 3 * - DBL_EPSILON; - that->bluef = that->bluef * that->alphaf + component; - that->bluee = that->bluee * that->alphaf + that->bluef * 3 * - DBL_EPSILON; - } - - /* Remove the alpha type and set the alpha. */ - that->alphaf = 1; - that->alphae = 0; - - if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA) - that->colour_type = PNG_COLOR_TYPE_RGB; - else if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA) - that->colour_type = PNG_COLOR_TYPE_GRAY; - } - - this->next->mod(this->next, that, pp, display); -} - -#define image_transform_png_set_background_add image_transform_default_add - -IT(background,rgb_to_gray); - -static image_transform *PNG_CONST image_transform_first = &ITSTRUCT(background); - -static void -transform_enable(PNG_CONST char *name) -{ - /* Everything starts out enabled, so if we see an 'enable' disabled - * everything else the first time round. - */ - static int all_disabled = 0; - int found_it = 0; - image_transform *list = image_transform_first; - - while (list != &image_transform_end) - { - if (strcmp(list->name, name) == 0) - { - list->enable = 1; - found_it = 1; - } - else if (!all_disabled) - list->enable = 0; - - list = list->list; - } - - all_disabled = 1; - - if (!found_it) - { - fprintf(stderr, "pngvalid: --transform-enable=%s: unknown transform\n", - name); - exit(1); - } -} - -static void -transform_disable(PNG_CONST char *name) -{ - image_transform *list = image_transform_first; - - while (list != &image_transform_end) - { - if (strcmp(list->name, name) == 0) - { - list->enable = 0; - return; - } - - list = list->list; - } - - fprintf(stderr, "pngvalid: --transform-disable=%s: unknown transform\n", - name); - exit(1); -} - -static void -image_transform_reset_count(void) -{ - image_transform *next = image_transform_first; - int count = 0; - - while (next != &image_transform_end) - { - next->local_use = 0; - next->next = 0; - next = next->list; - ++count; - } - - /* This can only happen if we every have more than 32 transforms (excluding - * the end) in the list. - */ - if (count > 32) abort(); -} - -static int -image_transform_test_counter(png_uint_32 counter, unsigned int max) -{ - /* Test the list to see if there is any point contining, given a current - * counter and a 'max' value. - */ - image_transform *next = image_transform_first; - - while (next != &image_transform_end) - { - /* For max 0 or 1 continue until the counter overflows: */ - counter >>= 1; - - /* Continue if any entry hasn't reacked the max. */ - if (max > 1 && next->local_use < max) - return 1; - next = next->list; - } - - return max <= 1 && counter == 0; -} - -static png_uint_32 -image_transform_add(PNG_CONST image_transform **this, unsigned int max, - png_uint_32 counter, char *name, size_t sizeof_name, size_t *pos, - png_byte colour_type, png_byte bit_depth) -{ - for (;;) /* until we manage to add something */ - { - png_uint_32 mask; - image_transform *list; - - /* Find the next counter value, if the counter is zero this is the start - * of the list. This routine always returns the current counter (not the - * next) so it returns 0 at the end and expects 0 at the beginning. - */ - if (counter == 0) /* first time */ - { - image_transform_reset_count(); - if (max <= 1) - counter = 1; - else - counter = random_32(); - } - else /* advance the counter */ - { - switch (max) - { - case 0: ++counter; break; - case 1: counter <<= 1; break; - default: counter = random_32(); break; - } - } - - /* Now add all these items, if possible */ - *this = &image_transform_end; - list = image_transform_first; - mask = 1; - - /* Go through the whole list adding anything that the counter selects: */ - while (list != &image_transform_end) - { - if ((counter & mask) != 0 && list->enable && - (max == 0 || list->local_use < max)) - { - /* Candidate to add: */ - if (list->add(list, this, colour_type, bit_depth) || max == 0) - { - /* Added, so add to the name too. */ - *pos = safecat(name, sizeof_name, *pos, " +"); - *pos = safecat(name, sizeof_name, *pos, list->name); - } - - else - { - /* Not useful and max>0, so remvoe it from *this: */ - *this = list->next; - list->next = 0; - - /* And, since we know it isn't useful, stop it being added again - * in this run: - */ - list->local_use = max; - } - } - - mask <<= 1; - list = list->list; - } - - /* Now if anything was added we have something to do. */ - if (*this != &image_transform_end) - return counter; - - /* Nothing added, but was there anything in there to add? */ - if (!image_transform_test_counter(counter, max)) - return 0; - } -} - -#ifdef THIS_IS_THE_PROFORMA -static void -image_transform_png_set_@_set(PNG_CONST image_transform *this, - transform_display *that, png_structp pp, png_infop pi) -{ - png_set_@(pp); - this->next->set(this->next, that, pp, pi); -} - -static void -image_transform_png_set_@_mod(PNG_CONST image_transform *this, - image_pixel *that, png_structp pp, PNG_CONST transform_display *display) -{ - this->next->mod(this->next, that, pp, display); -} - -static int -image_transform_png_set_@_add(image_transform *this, - PNG_CONST image_transform **that, char *name, size_t sizeof_name, - size_t *pos, png_byte colour_type, png_byte bit_depth) -{ - this->next = *that; - *that = this; - - *pos = safecat(name, sizeof_name, *pos, " +@"); - - return 1; -} - -IT(@); -#endif - -/* png_set_quantize(png_structp, png_colorp palette, int num_palette, - * int maximum_colors, png_const_uint_16p histogram, int full_quantize) - * - * Very difficult to validate this! - */ -/*NOTE: TBD NYI */ - -/* The data layout transforms are handled by swapping our own channel data, - * necessarily these need to happen at the end of the transform list because the - * semantic of the channels changes after these are executed. Some of these, - * like set_shift and set_packing, can't be done at present because they change - * the layout of the data at the sub-sample level so sample() won't get the - * right answer. - */ -/* png_set_invert_alpha */ -/*NOTE: TBD NYI */ - -/* png_set_bgr */ -/*NOTE: TBD NYI */ - -/* png_set_swap_alpha */ -/*NOTE: TBD NYI */ - -/* png_set_swap */ -/*NOTE: TBD NYI */ - -/* png_set_filler, (png_structp png_ptr, png_uint_32 filler, int flags)); */ -/*NOTE: TBD NYI */ - -/* png_set_add_alpha, (png_structp png_ptr, png_uint_32 filler, int flags)); */ -/*NOTE: TBD NYI */ - -/* png_set_packing */ -/*NOTE: TBD NYI */ - -/* png_set_packswap */ -/*NOTE: TBD NYI */ - -/* png_set_invert_mono */ -/*NOTE: TBD NYI */ - -/* png_set_shift(png_structp, png_const_color_8p true_bits) */ -/*NOTE: TBD NYI */ - -static int -test_transform(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type, - int bdlo, int PNG_CONST bdhi, png_uint_32 max) -{ - for (; bdlo <= bdhi; ++bdlo) - { - PNG_CONST png_byte bit_depth = DEPTH(bdlo); - png_uint_32 counter = 0; - size_t base_pos; - char name[64]; - - base_pos = safecat(name, sizeof name, 0, "transform:"); - - for (;;) - { - size_t pos = base_pos; - PNG_CONST image_transform *list = 0; - - counter = image_transform_add(&list, max, counter, name, sizeof name, - &pos, colour_type, bit_depth); - - if (counter == 0) - break; - - /* The command line can change this to checking interlaced images. */ - transform_test(pm, FILEID(colour_type, bit_depth, pm->interlace_type, - 0, 0, 0), list, name); - - if (fail(pm)) - return 0; - } - } - - return 1; /* keep going */ -} - -static void -perform_transform_test(png_modifier *pm) -{ - /* Test each colour type over the valid range of bit depths (expressed as - * log2(bit_depth) in turn, stop as soon as any error is detected. - */ - if (!test_transform(pm, 0, 0, READ_BDHI, 1)) - return; - - if (!test_transform(pm, 2, 3, READ_BDHI, 1)) - return; - - if (!test_transform(pm, 3, 0, 3, 1)) - return; - - if (!test_transform(pm, 4, 3, READ_BDHI, 1)) - return; - - if (!test_transform(pm, 6, 3, READ_BDHI, 1)) - return; -} - - -/********************************* GAMMA TESTS ********************************/ -/* Gamma test images. */ -typedef struct gamma_modification -{ - png_modification this; - png_fixed_point gamma; -} gamma_modification; - -static int -gamma_modify(png_modifier *pm, png_modification *me, int add) -{ - UNUSED(add) - /* This simply dumps the given gamma value into the buffer. */ - png_save_uint_32(pm->buffer, 4); - png_save_uint_32(pm->buffer+4, CHUNK_gAMA); - png_save_uint_32(pm->buffer+8, ((gamma_modification*)me)->gamma); - return 1; -} - -static void -gamma_modification_init(gamma_modification *me, png_modifier *pm, double gammad) -{ - double g; - - modification_init(&me->this); - me->this.chunk = CHUNK_gAMA; - me->this.modify_fn = gamma_modify; - me->this.add = CHUNK_PLTE; - g = floor(gammad * 100000 + .5); - me->gamma = (png_fixed_point)g; - me->this.next = pm->modifications; - pm->modifications = &me->this; -} - -typedef struct srgb_modification -{ - png_modification this; - png_byte intent; -} srgb_modification; - -static int -srgb_modify(png_modifier *pm, png_modification *me, int add) -{ - UNUSED(add) - /* As above, ignore add and just make a new chunk */ - png_save_uint_32(pm->buffer, 1); - png_save_uint_32(pm->buffer+4, CHUNK_sRGB); - pm->buffer[8] = ((srgb_modification*)me)->intent; - return 1; -} - -static void -srgb_modification_init(srgb_modification *me, png_modifier *pm, png_byte intent) -{ - modification_init(&me->this); - me->this.chunk = CHUNK_sBIT; - - if (intent <= 3) /* if valid, else *delete* sRGB chunks */ - { - me->this.modify_fn = srgb_modify; - me->this.add = CHUNK_PLTE; - me->intent = intent; - } - - else - { - me->this.modify_fn = 0; - me->this.add = 0; - me->intent = 0; - } - - me->this.next = pm->modifications; - pm->modifications = &me->this; -} - -typedef struct sbit_modification -{ - png_modification this; - png_byte sbit; -} sbit_modification; - -static int -sbit_modify(png_modifier *pm, png_modification *me, int add) -{ - png_byte sbit = ((sbit_modification*)me)->sbit; - if (pm->bit_depth > sbit) - { - int cb = 0; - switch (pm->colour_type) - { - case 0: - cb = 1; - break; - - case 2: - case 3: - cb = 3; - break; - - case 4: - cb = 2; - break; - - case 6: - cb = 4; - break; - - default: - png_error(pm->this.pread, - "unexpected colour type in sBIT modification"); - } - - png_save_uint_32(pm->buffer, cb); - png_save_uint_32(pm->buffer+4, CHUNK_sBIT); - - while (cb > 0) - (pm->buffer+8)[--cb] = sbit; - - return 1; - } - else if (!add) - { - /* Remove the sBIT chunk */ - pm->buffer_count = pm->buffer_position = 0; - return 1; - } - else - return 0; /* do nothing */ -} - -static void -sbit_modification_init(sbit_modification *me, png_modifier *pm, png_byte sbit) -{ - modification_init(&me->this); - me->this.chunk = CHUNK_sBIT; - me->this.modify_fn = sbit_modify; - me->this.add = CHUNK_PLTE; - me->sbit = sbit; - me->this.next = pm->modifications; - pm->modifications = &me->this; -} - -/* Reader callbacks and implementations, where they differ from the standard - * ones. - */ -typedef struct gamma_display -{ - standard_display this; - - /* Parameters */ - png_modifier* pm; - double file_gamma; - double screen_gamma; - png_byte sbit; - int threshold_test; - PNG_CONST char* name; - int speed; - int use_input_precision; - int strip16; - - /* Local variables */ - double maxerrout; - double maxerrpc; - double maxerrabs; -} gamma_display; - -static void -gamma_display_init(gamma_display *dp, png_modifier *pm, png_uint_32 id, - double file_gamma, double screen_gamma, png_byte sbit, int threshold_test, - int speed, int use_input_precision, int strip16) -{ - /* Standard fields */ - standard_display_init(&dp->this, &pm->this, id, 0/*do_interlace*/); - - /* Parameter fields */ - dp->pm = pm; - dp->file_gamma = file_gamma; - dp->screen_gamma = screen_gamma; - dp->sbit = sbit; - dp->threshold_test = threshold_test; - dp->speed = speed; - dp->use_input_precision = use_input_precision; - dp->strip16 = strip16; - - /* Local variable fields */ - dp->maxerrout = dp->maxerrpc = dp->maxerrabs = 0; -} - -static void -gamma_info_imp(gamma_display *dp, png_structp pp, png_infop pi) -{ - /* Reuse the standard stuff as appropriate. */ - standard_info_part1(&dp->this, pp, pi); - - /* If requested strip 16 to 8 bits - this is handled automagically below - * because the output bit depth is read from the library. Note that there - * are interactions with sBIT but, internally, libpng makes sbit at most - * PNG_MAX_GAMMA_8 when doing the following. - */ - if (dp->strip16) -# ifdef PNG_READ_16_TO_8_SUPPORTED - png_set_strip_16(pp); -# else - png_error(pp, "strip16 (16 to 8 bit conversion) not supported"); -# endif - - png_read_update_info(pp, pi); - - /* Now we may get a different cbRow: */ - standard_info_part2(&dp->this, pp, pi, 1 /*images*/); -} - -static void -gamma_info(png_structp pp, png_infop pi) -{ - gamma_info_imp(png_get_progressive_ptr(pp), pp, pi); -} - -static void -gamma_image_validate(gamma_display *dp, png_structp pp, png_infop pi, - png_const_bytep pRow) -{ - /* Get some constants derived from the input and output file formats: */ - PNG_CONST png_byte sbit = dp->sbit; - PNG_CONST double file_gamma = dp->file_gamma; - PNG_CONST double screen_gamma = dp->screen_gamma; - PNG_CONST int use_input_precision = dp->use_input_precision; - PNG_CONST int speed = dp->speed; - PNG_CONST png_byte in_ct = dp->this.colour_type; - PNG_CONST png_byte in_bd = dp->this.bit_depth; - PNG_CONST png_uint_32 w = dp->this.w; - PNG_CONST png_uint_32 h = dp->this.h; - PNG_CONST size_t cbRow = dp->this.cbRow; - PNG_CONST png_byte out_ct = png_get_color_type(pp, pi); - PNG_CONST png_byte out_bd = png_get_bit_depth(pp, pi); - PNG_CONST unsigned int outmax = (1U<<out_bd)-1; - PNG_CONST double maxabs = abserr(dp->pm, out_bd); - PNG_CONST double maxout = outerr(dp->pm, out_bd); - PNG_CONST double maxpc = pcerr(dp->pm, out_bd); - - /* There are three sources of error, firstly the quantization in the - * file encoding, determined by sbit and/or the file depth, secondly - * the output (screen) gamma and thirdly the output file encoding. - * - * Since this API receives the screen and file gamma in double - * precision it is possible to calculate an exact answer given an input - * pixel value. Therefore we assume that the *input* value is exact - - * sample/maxsample - calculate the corresponding gamma corrected - * output to the limits of double precision arithmetic and compare with - * what libpng returns. - * - * Since the library must quantize the output to 8 or 16 bits there is - * a fundamental limit on the accuracy of the output of +/-.5 - this - * quantization limit is included in addition to the other limits - * specified by the paramaters to the API. (Effectively, add .5 - * everywhere.) - * - * The behavior of the 'sbit' paramter is defined by section 12.5 - * (sample depth scaling) of the PNG spec. That section forces the - * decoder to assume that the PNG values have been scaled if sBIT is - * present: - * - * png-sample = floor( input-sample * (max-out/max-in) + .5); - * - * This means that only a subset of the possible PNG values should - * appear in the input. However, the spec allows the encoder to use a - * variety of approximations to the above and doesn't require any - * restriction of the values produced. - * - * Nevertheless the spec requires that the upper 'sBIT' bits of the - * value stored in a PNG file be the original sample bits. - * Consequently the code below simply scales the top sbit bits by - * (1<<sbit)-1 to obtain an original sample value. - * - * Because there is limited precision in the input it is arguable that - * an acceptable result is any valid result from input-.5 to input+.5. - * The basic tests below do not do this, however if - * 'use_input_precision' is set a subsequent test is performed below. - */ - PNG_CONST int processing = (fabs(screen_gamma*file_gamma-1) >= - PNG_GAMMA_THRESHOLD && !dp->threshold_test && !speed && in_ct != 3) || - in_bd != out_bd; - - PNG_CONST unsigned int samples_per_pixel = (out_ct & 2U) ? 3U : 1U; - - PNG_CONST double gamma_correction = 1/(file_gamma*screen_gamma);/* Overall */ - - double maxerrout = 0, maxerrabs = 0, maxerrpc = 0; - png_uint_32 y; - - for (y=0; y<h; ++y, pRow += cbRow) - { - unsigned int s, x; - png_byte std[STANDARD_ROWMAX]; - - transform_row(pp, std, in_ct, in_bd, y); - - if (processing) - { - for (x=0; x<w; ++x) for (s=0; s<samples_per_pixel; ++s) - { - /* Input sample values: */ - PNG_CONST unsigned int - id = sample(std, in_ct, in_bd, x, s); - - PNG_CONST unsigned int - od = sample(pRow, out_ct, out_bd, x, s); - - PNG_CONST unsigned int - isbit = id >> (in_bd-sbit); - - double i, input_sample, encoded_sample, output; - double encoded_error, error; - double es_lo, es_hi; - - /* First check on the 'perfect' result obtained from the - * digitized input value, id, and compare this against the - * actual digitized result, 'od'. 'i' is the input result - * in the range 0..1: - * - * NOTE: sBIT should be taken into account here but isn't, - * as described above. - */ - i = isbit; i /= (1U<<sbit)-1; - - /* Then get the gamma corrected version of 'i' and compare - * to 'od', any error less than .5 is insignificant - just - * quantization of the output value to the nearest digital - * value (nevertheless the error is still recorded - it's - * interesting ;-) - */ - encoded_sample = pow(i, gamma_correction) * outmax; - encoded_error = fabs(od-encoded_sample); - - if (encoded_error > maxerrout) - maxerrout = encoded_error; - - if (encoded_error < .5+maxout) - continue; - - /* There may be an error, so calculate the actual sample - * values - unencoded light intensity values. Note that - * in practice these are not unencoded because they - * include a 'viewing correction' to decrease or - * (normally) increase the perceptual contrast of the - * image. There's nothing we can do about this - we don't - * know what it is - so assume the unencoded value is - * perceptually linear. - */ - input_sample = pow(i, 1/file_gamma); /* In range 0..1 */ - output = od; - output /= outmax; - output = pow(output, screen_gamma); - - /* Now we have the numbers for real errors, both absolute - * values as as a percentage of the correct value (output): - */ - error = fabs(input_sample-output); - - if (error > maxerrabs) - maxerrabs = error; - - /* The following is an attempt to ignore the tendency of - * quantization to dominate the percentage errors for low - * output sample values: - */ - if (input_sample*maxpc > .5+maxabs) - { - double percentage_error = error/input_sample; - if (percentage_error > maxerrpc) maxerrpc = percentage_error; - } - - /* Now calculate the digitization limits for - * 'encoded_sample' using the 'max' values. Note that - * maxout is in the encoded space but maxpc and maxabs are - * in linear light space. - * - * First find the maximum error in linear light space, - * range 0..1: - */ - { - double tmp = input_sample * maxpc; - if (tmp < maxabs) tmp = maxabs; - - /* Low bound - the minimum of the three: */ - es_lo = encoded_sample - maxout; - - if (es_lo > 0 && input_sample-tmp > 0) - { - double low_value = outmax * pow(input_sample-tmp, - 1/screen_gamma); - if (low_value < es_lo) es_lo = low_value; - } - - else - es_lo = 0; - - es_hi = encoded_sample + maxout; - - if (es_hi < outmax && input_sample+tmp < 1) - { - double high_value = outmax * pow(input_sample+tmp, - 1/screen_gamma); - if (high_value > es_hi) es_hi = high_value; - } - - else - es_hi = outmax; - } - - /* The primary test is that the final encoded value - * returned by the library should be between the two limits - * (inclusive) that were calculated above. At this point - * quantization of the output must be taken into account. - */ - if (od+.5 < es_lo || od-.5 > es_hi) - { - /* There has been an error in processing. */ - double is_lo, is_hi; - - if (use_input_precision) - { - /* Ok, something is wrong - this actually happens in - * current libpng sbit processing. Assume that the - * input value (id, adjusted for sbit) can be - * anywhere between value-.5 and value+.5 - quite a - * large range if sbit is low. - */ - double tmp = (isbit - .5)/((1U<<sbit)-1); - - if (tmp > 0) - { - is_lo = outmax * pow(tmp, gamma_correction) - maxout; - if (is_lo < 0) is_lo = 0; - } - - else - is_lo = 0; - - tmp = (isbit + .5)/((1U<<sbit)-1); - - if (tmp < 1) - { - is_hi = outmax * pow(tmp, gamma_correction) + maxout; - if (is_hi > outmax) is_hi = outmax; - } - - else - is_hi = outmax; - - if (!(od+.5 < is_lo || od-.5 > is_hi)) - continue; - } - else - is_lo = es_lo, is_hi = es_hi; - - { - char msg[256]; - - sprintf(msg, - "error: %.3f; %u{%u;%u} -> %u not %.2f (%.1f-%.1f)", - od-encoded_sample, id, sbit, isbit, od, - encoded_sample, is_lo, is_hi); - - png_warning(pp, msg); - } - } - } - } - - else if (!speed && memcmp(std, pRow, cbRow) != 0) - { - char msg[64]; - - /* No transform is expected on the threshold tests. */ - sprintf(msg, "gamma: below threshold row %d changed", y); - - png_error(pp, msg); - } - } /* row (y) loop */ - - dp->maxerrout = maxerrout; - dp->maxerrabs = maxerrabs; - dp->maxerrpc = maxerrpc; - dp->this.ps->validated = 1; -} - -static void -gamma_end(png_structp pp, png_infop pi) -{ - gamma_display *dp = png_get_progressive_ptr(pp); - - gamma_image_validate(dp, pp, pi, dp->this.ps->image); -} - -/* A single test run checking a gamma transformation. - * - * maxabs: maximum absolute error as a fraction - * maxout: maximum output error in the output units - * maxpc: maximum percentage error (as a percentage) - */ -static void -gamma_test(png_modifier *pmIn, PNG_CONST png_byte colour_typeIn, - PNG_CONST png_byte bit_depthIn, PNG_CONST int interlace_typeIn, - PNG_CONST double file_gammaIn, PNG_CONST double screen_gammaIn, - PNG_CONST png_byte sbitIn, PNG_CONST int threshold_testIn, - PNG_CONST char *name, PNG_CONST int speedIn, - PNG_CONST int use_input_precisionIn, PNG_CONST int strip16In) -{ - gamma_display d; - context(&pmIn->this, fault); - - gamma_display_init(&d, pmIn, FILEID(colour_typeIn, bit_depthIn, - interlace_typeIn, 0, 0, 0), file_gammaIn, screen_gammaIn, sbitIn, - threshold_testIn, speedIn, use_input_precisionIn, strip16In); - - Try - { - png_structp pp; - png_infop pi; - gamma_modification gamma_mod; - srgb_modification srgb_mod; - sbit_modification sbit_mod; - - /* Make an appropriate modifier to set the PNG file gamma to the - * given gamma value and the sBIT chunk to the given precision. - */ - d.pm->modifications = NULL; - gamma_modification_init(&gamma_mod, d.pm, d.file_gamma); - srgb_modification_init(&srgb_mod, d.pm, 127 /*delete*/); - sbit_modification_init(&sbit_mod, d.pm, d.sbit); - - modification_reset(d.pm->modifications); - - /* Get a png_struct for writing the image. */ - pp = set_modifier_for_read(d.pm, &pi, d.this.id, name); - - /* Set up gamma processing. */ -#ifdef PNG_FLOATING_POINT_SUPPORTED - png_set_gamma(pp, d.screen_gamma, d.file_gamma); -#else - { - png_fixed_point s = floor(d.screen_gamma*100000+.5); - png_fixed_point f = floor(d.file_gamma*100000+.5); - png_set_gamma_fixed(pp, s, f); - } -#endif - - /* Introduce the correct read function. */ - if (d.pm->this.progressive) - { - /* Share the row function with the standard implementation. */ - png_set_progressive_read_fn(pp, &d, gamma_info, progressive_row, - gamma_end); - - /* Now feed data into the reader until we reach the end: */ - modifier_progressive_read(d.pm, pp, pi); - } - else - { - /* modifier_read expects a png_modifier* */ - png_set_read_fn(pp, d.pm, modifier_read); - - /* Check the header values: */ - png_read_info(pp, pi); - - /* Process the 'info' requirements. Only one image is generated */ - gamma_info_imp(&d, pp, pi); - - sequential_row(&d.this, pp, pi, NULL, d.this.ps->image); - - gamma_image_validate(&d, pp, pi, d.this.ps->image); - } - - modifier_reset(d.pm); - - if (d.pm->log && !d.threshold_test && !d.speed) - fprintf(stderr, "%d bit %s %s: max error %f (%.2g, %2g%%)\n", - d.this.bit_depth, colour_types[d.this.colour_type], d.name, - d.maxerrout, d.maxerrabs, 100*d.maxerrpc); - - /* Log the summary values too. */ - if (d.this.colour_type == 0 || d.this.colour_type == 4) - { - switch (d.this.bit_depth) - { - case 1: - break; - - case 2: - if (d.maxerrout > d.pm->error_gray_2) - d.pm->error_gray_2 = d.maxerrout; - - break; - - case 4: - if (d.maxerrout > d.pm->error_gray_4) - d.pm->error_gray_4 = d.maxerrout; - - break; - - case 8: - if (d.maxerrout > d.pm->error_gray_8) - d.pm->error_gray_8 = d.maxerrout; - - break; - - case 16: - if (d.maxerrout > d.pm->error_gray_16) - d.pm->error_gray_16 = d.maxerrout; - - break; - - default: - png_error(pp, "bad bit depth (internal: 1)"); - } - } - - else if (d.this.colour_type == 2 || d.this.colour_type == 6) - { - switch (d.this.bit_depth) - { - case 8: - - if (d.maxerrout > d.pm->error_color_8) - d.pm->error_color_8 = d.maxerrout; - - break; - - case 16: - - if (d.maxerrout > d.pm->error_color_16) - d.pm->error_color_16 = d.maxerrout; - - break; - - default: - png_error(pp, "bad bit depth (internal: 2)"); - } - } - } - - Catch(fault) - modifier_reset((png_modifier*)fault); -} - -static void gamma_threshold_test(png_modifier *pm, png_byte colour_type, - png_byte bit_depth, int interlace_type, double file_gamma, - double screen_gamma) -{ - size_t pos = 0; - char name[64]; - pos = safecat(name, sizeof name, pos, "threshold "); - pos = safecatd(name, sizeof name, pos, file_gamma, 3); - pos = safecat(name, sizeof name, pos, "/"); - pos = safecatd(name, sizeof name, pos, screen_gamma, 3); - - (void)gamma_test(pm, colour_type, bit_depth, interlace_type, file_gamma, - screen_gamma, bit_depth, 1, name, 0 /*speed*/, 0 /*no input precision*/, - 0 /*no strip16*/); -} - -static void -perform_gamma_threshold_tests(png_modifier *pm) -{ - png_byte colour_type = 0; - png_byte bit_depth = 0; - - while (next_format(&colour_type, &bit_depth)) - { - double test_gamma = 1.0; - while (test_gamma >= .4) - { - /* There's little point testing the interlacing vs non-interlacing, - * but this can be set from the command line. - */ - gamma_threshold_test(pm, colour_type, bit_depth, pm->interlace_type, - test_gamma, 1/test_gamma); - test_gamma *= .95; - } - - /* And a special test for sRGB */ - gamma_threshold_test(pm, colour_type, bit_depth, pm->interlace_type, - .45455, 2.2); - - if (fail(pm)) - return; - } -} - -static void gamma_transform_test(png_modifier *pm, - PNG_CONST png_byte colour_type, PNG_CONST png_byte bit_depth, - PNG_CONST int interlace_type, PNG_CONST double file_gamma, - PNG_CONST double screen_gamma, PNG_CONST png_byte sbit, PNG_CONST int speed, - PNG_CONST int use_input_precision, PNG_CONST int strip16) -{ - size_t pos = 0; - char name[64]; - - if (sbit != bit_depth) - { - pos = safecat(name, sizeof name, pos, "sbit("); - pos = safecatn(name, sizeof name, pos, sbit); - pos = safecat(name, sizeof name, pos, ") "); - } - - else - pos = safecat(name, sizeof name, pos, "gamma "); - - if (strip16) - pos = safecat(name, sizeof name, pos, "16to8 "); - - pos = safecatd(name, sizeof name, pos, file_gamma, 3); - pos = safecat(name, sizeof name, pos, "->"); - pos = safecatd(name, sizeof name, pos, screen_gamma, 3); - - gamma_test(pm, colour_type, bit_depth, interlace_type, file_gamma, - screen_gamma, sbit, 0, name, speed, use_input_precision, strip16); -} - -static void perform_gamma_transform_tests(png_modifier *pm, int speed) -{ - png_byte colour_type = 0; - png_byte bit_depth = 0; - - /* Ignore palette images - the gamma correction happens on the palette entry, - * haven't got the tests for this yet. - */ - while (next_format(&colour_type, &bit_depth)) if (colour_type != 3) - { - unsigned int i, j; - - for (i=0; i<pm->ngammas; ++i) for (j=0; j<pm->ngammas; ++j) if (i != j) - { - gamma_transform_test(pm, colour_type, bit_depth, pm->interlace_type, - 1/pm->gammas[i], pm->gammas[j], bit_depth, speed, - pm->use_input_precision, 0 /*do not strip16*/); - - if (fail(pm)) - return; - } - } -} - -static void perform_gamma_sbit_tests(png_modifier *pm, int speed) -{ - png_byte sbit; - - /* The only interesting cases are colour and grayscale, alpha is ignored here - * for overall speed. Only bit depths 8 and 16 are tested. - */ - for (sbit=pm->sbitlow; sbit<(1<<READ_BDHI); ++sbit) - { - unsigned int i, j; - - for (i=0; i<pm->ngammas; ++i) - { - for (j=0; j<pm->ngammas; ++j) - { - if (i != j) - { - if (sbit < 8) - { - gamma_transform_test(pm, 0, 8, pm->interlace_type, - 1/pm->gammas[i], pm->gammas[j], sbit, speed, - pm->use_input_precision_sbit, 0 /*strip16*/); - - if (fail(pm)) - return; - - gamma_transform_test(pm, 2, 8, pm->interlace_type, - 1/pm->gammas[i], pm->gammas[j], sbit, speed, - pm->use_input_precision_sbit, 0 /*strip16*/); - - if (fail(pm)) - return; - } - -#ifdef DO_16BIT - gamma_transform_test(pm, 0, 16, pm->interlace_type, - 1/pm->gammas[i], pm->gammas[j], sbit, speed, - pm->use_input_precision_sbit, 0 /*strip16*/); - - if (fail(pm)) - return; - - gamma_transform_test(pm, 2, 16, pm->interlace_type, - 1/pm->gammas[i], pm->gammas[j], sbit, speed, - pm->use_input_precision_sbit, 0 /*strip16*/); - - if (fail(pm)) - return; -#endif - } - } - } - } -} - -/* Note that this requires a 16 bit source image but produces 8 bit output, so - * we only need the 16bit write support. - */ -#ifdef PNG_READ_16_TO_8_SUPPORTED -static void perform_gamma_strip16_tests(png_modifier *pm, int speed) -{ -# ifndef PNG_MAX_GAMMA_8 -# define PNG_MAX_GAMMA_8 11 -# endif - /* Include the alpha cases here. Note that sbit matches the internal value - * used by the library - otherwise we will get spurious errors from the - * internal sbit style approximation. - * - * The threshold test is here because otherwise the 16 to 8 conversion will - * proceed *without* gamma correction, and the tests above will fail (but not - * by much) - this could be fixed, it only appears with the -g option. - */ - unsigned int i, j; - for (i=0; i<pm->ngammas; ++i) - { - for (j=0; j<pm->ngammas; ++j) - { - if (i != j && - fabs(pm->gammas[j]/pm->gammas[i]-1) >= PNG_GAMMA_THRESHOLD) - { - gamma_transform_test(pm, 0, 16, pm->interlace_type, 1/pm->gammas[i], - pm->gammas[j], PNG_MAX_GAMMA_8, speed, - pm->use_input_precision_16to8, 1 /*strip16*/); - - if (fail(pm)) - return; - - gamma_transform_test(pm, 2, 16, pm->interlace_type, 1/pm->gammas[i], - pm->gammas[j], PNG_MAX_GAMMA_8, speed, - pm->use_input_precision_16to8, 1 /*strip16*/); - - if (fail(pm)) - return; - - gamma_transform_test(pm, 4, 16, pm->interlace_type, 1/pm->gammas[i], - pm->gammas[j], PNG_MAX_GAMMA_8, speed, - pm->use_input_precision_16to8, 1 /*strip16*/); - - if (fail(pm)) - return; - - gamma_transform_test(pm, 6, 16, pm->interlace_type, 1/pm->gammas[i], - pm->gammas[j], PNG_MAX_GAMMA_8, speed, - pm->use_input_precision_16to8, 1 /*strip16*/); - - if (fail(pm)) - return; - } - } - } -} -#endif /* 16 to 8 bit conversion */ - -static void -perform_gamma_test(png_modifier *pm, int speed, int summary) -{ - /* First some arbitrary no-transform tests: */ - if (!speed && pm->test_gamma_threshold) - { - perform_gamma_threshold_tests(pm); - - if (fail(pm)) - return; - } - - /* Now some real transforms. */ - if (pm->test_gamma_transform) - { - perform_gamma_transform_tests(pm, speed); - - if (summary) - { - printf("Gamma correction error summary\n\n"); - printf("The printed value is the maximum error in the pixel values\n"); - printf("calculated by the libpng gamma correction code. The error\n"); - printf("is calculated as the difference between the output pixel\n"); - printf("value (always an integer) and the ideal value from the\n"); - printf("libpng specification (typically not an integer).\n\n"); - - printf("Expect this value to be less than .5 for 8 bit formats,\n"); - printf("less than 1 for formats with fewer than 8 bits and a small\n"); - printf("number (typically less than 5) for the 16 bit formats.\n"); - printf("For performance reasons the value for 16 bit formats\n"); - printf("increases when the image file includes an sBIT chunk.\n\n"); - - printf(" 2 bit gray: %.5f\n", pm->error_gray_2); - printf(" 4 bit gray: %.5f\n", pm->error_gray_4); - printf(" 8 bit gray: %.5f\n", pm->error_gray_8); - printf(" 8 bit color: %.5f\n", pm->error_color_8); -#ifdef DO_16BIT - printf(" 16 bit gray: %.5f\n", pm->error_gray_16); - printf(" 16 bit color: %.5f\n", pm->error_color_16); -#endif - } - } - - /* The sbit tests produce much larger errors: */ - if (pm->test_gamma_sbit) - { - pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = - pm->error_gray_16 = pm->error_color_8 = pm->error_color_16 = 0; - perform_gamma_sbit_tests(pm, speed); - - if (summary) - { - printf("Gamma correction with sBIT:\n"); - - if (pm->sbitlow < 8U) - { - printf(" 2 bit gray: %.5f\n", pm->error_gray_2); - printf(" 4 bit gray: %.5f\n", pm->error_gray_4); - printf(" 8 bit gray: %.5f\n", pm->error_gray_8); - printf(" 8 bit color: %.5f\n", pm->error_color_8); - } - - #ifdef DO_16BIT - printf(" 16 bit gray: %.5f\n", pm->error_gray_16); - printf(" 16 bit color: %.5f\n", pm->error_color_16); - #endif - } - } - -#ifdef PNG_READ_16_TO_8_SUPPORTED - if (pm->test_gamma_strip16) - { - /* The 16 to 8 bit strip operations: */ - pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = - pm->error_gray_16 = pm->error_color_8 = pm->error_color_16 = 0; - perform_gamma_strip16_tests(pm, speed); - - if (summary) - { - printf("Gamma correction with 16 to 8 bit reduction:\n"); - printf(" 16 bit gray: %.5f\n", pm->error_gray_16); - printf(" 16 bit color: %.5f\n", pm->error_color_16); - } - } -#endif -} - -/* INTERLACE MACRO VALIDATION */ -/* This is copied verbatim from the specification, it is simply the pass - * number in which each pixel in each 8x8 tile appears. The array must - * be indexed adam7[y][x] and notice that the pass numbers are based at - * 1, not 0 - the base libpng uses. - */ -static PNG_CONST -png_byte adam7[8][8] = -{ - { 1,6,4,6,2,6,4,6 }, - { 7,7,7,7,7,7,7,7 }, - { 5,6,5,6,5,6,5,6 }, - { 7,7,7,7,7,7,7,7 }, - { 3,6,4,6,3,6,4,6 }, - { 7,7,7,7,7,7,7,7 }, - { 5,6,5,6,5,6,5,6 }, - { 7,7,7,7,7,7,7,7 } -}; - -/* This routine validates all the interlace support macros in png.h for - * a variety of valid PNG widths and heights. It uses a number of similarly - * named internal routines that feed off the above array. - */ -static png_uint_32 -png_pass_start_row(int pass) -{ - int x, y; - ++pass; - for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass) - return y; - return 0xf; -} - -static png_uint_32 -png_pass_start_col(int pass) -{ - int x, y; - ++pass; - for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass) - return x; - return 0xf; -} - -static int -png_pass_row_shift(int pass) -{ - int x, y, base=(-1), inc=8; - ++pass; - for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass) - { - if (base == (-1)) - base = y; - else if (base == y) - {} - else if (inc == y-base) - base=y; - else if (inc == 8) - inc = y-base, base=y; - else if (inc != y-base) - return 0xff; /* error - more than one 'inc' value! */ - } - - if (base == (-1)) return 0xfe; /* error - no row in pass! */ - - /* The shift is always 1, 2 or 3 - no pass has all the rows! */ - switch (inc) - { -case 2: return 1; -case 4: return 2; -case 8: return 3; -default: break; - } - - /* error - unrecognized 'inc' */ - return (inc << 8) + 0xfd; -} - -static int -png_pass_col_shift(int pass) -{ - int x, y, base=(-1), inc=8; - ++pass; - for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass) - { - if (base == (-1)) - base = x; - else if (base == x) - {} - else if (inc == x-base) - base=x; - else if (inc == 8) - inc = x-base, base=x; - else if (inc != x-base) - return 0xff; /* error - more than one 'inc' value! */ - } - - if (base == (-1)) return 0xfe; /* error - no row in pass! */ - - /* The shift is always 1, 2 or 3 - no pass has all the rows! */ - switch (inc) - { -case 1: return 0; /* pass 7 has all the columns */ -case 2: return 1; -case 4: return 2; -case 8: return 3; -default: break; - } - - /* error - unrecognized 'inc' */ - return (inc << 8) + 0xfd; -} - -static png_uint_32 -png_row_from_pass_row(png_uint_32 yIn, int pass) -{ - /* By examination of the array: */ - switch (pass) - { -case 0: return yIn * 8; -case 1: return yIn * 8; -case 2: return yIn * 8 + 4; -case 3: return yIn * 4; -case 4: return yIn * 4 + 2; -case 5: return yIn * 2; -case 6: return yIn * 2 + 1; -default: break; - } - - return 0xff; /* bad pass number */ -} - -static png_uint_32 -png_col_from_pass_col(png_uint_32 xIn, int pass) -{ - /* By examination of the array: */ - switch (pass) - { -case 0: return xIn * 8; -case 1: return xIn * 8 + 4; -case 2: return xIn * 4; -case 3: return xIn * 4 + 2; -case 4: return xIn * 2; -case 5: return xIn * 2 + 1; -case 6: return xIn; -default: break; - } - - return 0xff; /* bad pass number */ -} - -static int -png_row_in_interlace_pass(png_uint_32 y, int pass) -{ - /* Is row 'y' in pass 'pass'? */ - int x; - y &= 7; - ++pass; - for (x=0; x<8; ++x) if (adam7[y][x] == pass) - return 1; - - return 0; -} - -static int -png_col_in_interlace_pass(png_uint_32 x, int pass) -{ - /* Is column 'x' in pass 'pass'? */ - int y; - x &= 7; - ++pass; - for (y=0; y<8; ++y) if (adam7[y][x] == pass) - return 1; - - return 0; -} - -static png_uint_32 -png_pass_rows(png_uint_32 height, int pass) -{ - png_uint_32 tiles = height>>3; - png_uint_32 rows = 0; - unsigned int x, y; - - height &= 7; - ++pass; - for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass) - { - rows += tiles; - if (y < height) ++rows; - break; /* i.e. break the 'x', column, loop. */ - } - - return rows; -} - -static png_uint_32 -png_pass_cols(png_uint_32 width, int pass) -{ - png_uint_32 tiles = width>>3; - png_uint_32 cols = 0; - unsigned int x, y; - - width &= 7; - ++pass; - for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass) - { - cols += tiles; - if (x < width) ++cols; - break; /* i.e. break the 'y', row, loop. */ - } - - return cols; -} - -static void -perform_interlace_macro_validation(void) -{ - /* The macros to validate, first those that depend only on pass: - * - * PNG_PASS_START_ROW(pass) - * PNG_PASS_START_COL(pass) - * PNG_PASS_ROW_SHIFT(pass) - * PNG_PASS_COL_SHIFT(pass) - */ - int pass; - - for (pass=0; pass<7; ++pass) - { - png_uint_32 m, f, v; - - m = PNG_PASS_START_ROW(pass); - f = png_pass_start_row(pass); - if (m != f) - { - fprintf(stderr, "PNG_PASS_START_ROW(%d) = %u != %x\n", pass, m, f); - exit(1); - } - - m = PNG_PASS_START_COL(pass); - f = png_pass_start_col(pass); - if (m != f) - { - fprintf(stderr, "PNG_PASS_START_COL(%d) = %u != %x\n", pass, m, f); - exit(1); - } - - m = PNG_PASS_ROW_SHIFT(pass); - f = png_pass_row_shift(pass); - if (m != f) - { - fprintf(stderr, "PNG_PASS_ROW_SHIFT(%d) = %u != %x\n", pass, m, f); - exit(1); - } - - m = PNG_PASS_COL_SHIFT(pass); - f = png_pass_col_shift(pass); - if (m != f) - { - fprintf(stderr, "PNG_PASS_COL_SHIFT(%d) = %u != %x\n", pass, m, f); - exit(1); - } - - /* Macros that depend on the image or sub-image height too: - * - * PNG_PASS_ROWS(height, pass) - * PNG_PASS_COLS(width, pass) - * PNG_ROW_FROM_PASS_ROW(yIn, pass) - * PNG_COL_FROM_PASS_COL(xIn, pass) - * PNG_ROW_IN_INTERLACE_PASS(y, pass) - * PNG_COL_IN_INTERLACE_PASS(x, pass) - */ - for (v=0;;) - { - /* First the base 0 stuff: */ - m = PNG_ROW_FROM_PASS_ROW(v, pass); - f = png_row_from_pass_row(v, pass); - if (m != f) - { - fprintf(stderr, "PNG_ROW_FROM_PASS_ROW(%u, %d) = %u != %x\n", - v, pass, m, f); - exit(1); - } - - m = PNG_COL_FROM_PASS_COL(v, pass); - f = png_col_from_pass_col(v, pass); - if (m != f) - { - fprintf(stderr, "PNG_COL_FROM_PASS_COL(%u, %d) = %u != %x\n", - v, pass, m, f); - exit(1); - } - - m = PNG_ROW_IN_INTERLACE_PASS(v, pass); - f = png_row_in_interlace_pass(v, pass); - if (m != f) - { - fprintf(stderr, "PNG_ROW_IN_INTERLACE_PASS(%u, %d) = %u != %x\n", - v, pass, m, f); - exit(1); - } - - m = PNG_COL_IN_INTERLACE_PASS(v, pass); - f = png_col_in_interlace_pass(v, pass); - if (m != f) - { - fprintf(stderr, "PNG_COL_IN_INTERLACE_PASS(%u, %d) = %u != %x\n", - v, pass, m, f); - exit(1); - } - - /* Then the base 1 stuff: */ - ++v; - m = PNG_PASS_ROWS(v, pass); - f = png_pass_rows(v, pass); - if (m != f) - { - fprintf(stderr, "PNG_PASS_ROWS(%u, %d) = %u != %x\n", - v, pass, m, f); - exit(1); - } - - m = PNG_PASS_COLS(v, pass); - f = png_pass_cols(v, pass); - if (m != f) - { - fprintf(stderr, "PNG_PASS_COLS(%u, %d) = %u != %x\n", - v, pass, m, f); - exit(1); - } - - /* Move to the next v - the stepping algorithm starts skipping - * values above 1024. - */ - if (v > 1024) - { - if (v == PNG_UINT_31_MAX) - break; - - v = (v << 1) ^ v; - if (v >= PNG_UINT_31_MAX) - v = PNG_UINT_31_MAX-1; - } - } - } -} - -/* main program */ -int main(int argc, PNG_CONST char **argv) -{ - volatile int summary = 1; /* Print the error summary at the end */ - - /* Create the given output file on success: */ - PNG_CONST char *volatile touch = NULL; - - /* This is an array of standard gamma values (believe it or not I've seen - * every one of these mentioned somewhere.) - * - * In the following list the most useful values are first! - */ - static double - gammas[]={2.2, 1.0, 2.2/1.45, 1.8, 1.5, 2.4, 2.5, 2.62, 2.9}; - - png_modifier pm; - context(&pm.this, fault); - - modifier_init(&pm); - - /* Preallocate the image buffer, because we know how big it needs to be, - * note that, for testing purposes, it is deliberately mis-aligned. - */ - pm.this.image = malloc(2*TRANSFORM_IMAGEMAX+1); - - if (pm.this.image != NULL) - { - /* Ignore OOM at this point - the 'ensure' routine above will allocate - * the array appropriately. - */ - ++(pm.this.image); - pm.this.cb_image = 2*TRANSFORM_IMAGEMAX; - } - - /* Default to error on warning: */ - pm.this.treat_warnings_as_errors = 1; - - /* Store the test gammas */ - pm.gammas = gammas; - pm.ngammas = 0; /* default to off */ - pm.sbitlow = 8U; /* because libpng doesn't do sBIT below 8! */ - pm.use_input_precision_16to8 = 1U; /* Because of the way libpng does it */ - - /* Some default values (set the behavior for 'make check' here). - * These values simply control the maximum error permitted in the gamma - * transformations. The practial limits for human perception are described - * below (the setting for maxpc16), however for 8 bit encodings it isn't - * possible to meet the accepted capabilities of human vision - i.e. 8 bit - * images can never be good enough, regardless of encoding. - */ - pm.maxout8 = .1; /* Arithmetic error in *encoded* value */ - pm.maxabs8 = .00005; /* 1/20000 */ - pm.maxpc8 = .499; /* I.e., .499% fractional error */ - pm.maxout16 = .499; /* Error in *encoded* value */ - pm.maxabs16 = .00005;/* 1/20000 */ - - /* NOTE: this is a reasonable perceptual limit. We assume that humans can - * perceive light level differences of 1% over a 100:1 range, so we need to - * maintain 1 in 10000 accuracy (in linear light space), which is what the - * following guarantees. It also allows significantly higher errors at - * higher 16 bit values, which is important for performance. The actual - * maximum 16 bit error is about +/-1.9 in the fixed point implementation but - * this is only allowed for values >38149 by the following: - */ - pm.maxpc16 = .005; /* I.e., 1/200% - 1/20000 */ - - /* Now parse the command line options. */ - while (--argc >= 1) - { - if (strcmp(*++argv, "-v") == 0) - pm.this.verbose = 1; - - else if (strcmp(*argv, "-l") == 0) - pm.log = 1; - - else if (strcmp(*argv, "-q") == 0) - summary = pm.this.verbose = pm.log = 0; - - else if (strcmp(*argv, "-w") == 0) - pm.this.treat_warnings_as_errors = 0; - - else if (strcmp(*argv, "--speed") == 0) - pm.this.speed = 1, pm.ngammas = (sizeof gammas)/(sizeof gammas[0]), - pm.test_standard = 0; - - else if (strcmp(*argv, "--size") == 0) - pm.test_size = 1; - - else if (strcmp(*argv, "--nosize") == 0) - pm.test_size = 0; - - else if (strcmp(*argv, "--standard") == 0) - pm.test_standard = 1; - - else if (strcmp(*argv, "--nostandard") == 0) - pm.test_standard = 0; - - else if (strcmp(*argv, "--transform") == 0) - pm.test_transform = 1; - - else if (strcmp(*argv, "--notransform") == 0) - pm.test_transform = 0; - - else if (strncmp(*argv, "--transform-disable=", - sizeof "--transform-disable") == 0) - { - pm.test_transform = 1; - transform_disable(*argv + sizeof "--transform-disable"); - } - - else if (strncmp(*argv, "--transform-enable=", - sizeof "--transform-enable") == 0) - { - pm.test_transform = 1; - transform_enable(*argv + sizeof "--transform-enable"); - } - - else if (strcmp(*argv, "--gamma") == 0) - { - /* Just do two gamma tests here (2.2 and linear) for speed: */ - pm.ngammas = 2U; - pm.test_gamma_threshold = 1; - pm.test_gamma_transform = 1; - pm.test_gamma_sbit = 1; - pm.test_gamma_strip16 = 1; - } - - else if (strcmp(*argv, "--nogamma") == 0) - pm.ngammas = 0; - - else if (strcmp(*argv, "--gamma-threshold") == 0) - pm.ngammas = 2U, pm.test_gamma_threshold = 1; - - else if (strcmp(*argv, "--nogamma-threshold") == 0) - pm.test_gamma_threshold = 0; - - else if (strcmp(*argv, "--gamma-transform") == 0) - pm.ngammas = 2U, pm.test_gamma_transform = 1; - - else if (strcmp(*argv, "--nogamma-transform") == 0) - pm.test_gamma_transform = 0; - - else if (strcmp(*argv, "--gamma-sbit") == 0) - pm.ngammas = 2U, pm.test_gamma_sbit = 1; - - else if (strcmp(*argv, "--nogamma-sbit") == 0) - pm.test_gamma_sbit = 0; - - else if (strcmp(*argv, "--gamma-16-to-8") == 0) - pm.ngammas = 2U, pm.test_gamma_strip16 = 1; - - else if (strcmp(*argv, "--nogamma-16-to-8") == 0) - pm.test_gamma_strip16 = 0; - - else if (strcmp(*argv, "--all-gammas") == 0) - pm.ngammas = (sizeof gammas)/(sizeof gammas[0]); - - else if (strcmp(*argv, "--progressive-read") == 0) - pm.this.progressive = 1; - - else if (strcmp(*argv, "--interlace") == 0) - pm.interlace_type = PNG_INTERLACE_ADAM7; - - else if (argc >= 1 && strcmp(*argv, "--sbitlow") == 0) - --argc, pm.sbitlow = (png_byte)atoi(*++argv); - - else if (argc >= 1 && strcmp(*argv, "--touch") == 0) - --argc, touch = *++argv; - - else if (argc >= 1 && strncmp(*argv, "--max", 4) == 0) - { - --argc; - - if (strcmp(4+*argv, "abs8") == 0) - pm.maxabs8 = atof(*++argv); - - else if (strcmp(4+*argv, "abs16") == 0) - pm.maxabs16 = atof(*++argv); - - else if (strcmp(4+*argv, "out8") == 0) - pm.maxout8 = atof(*++argv); - - else if (strcmp(4+*argv, "out16") == 0) - pm.maxout16 = atof(*++argv); - - else if (strcmp(4+*argv, "pc8") == 0) - pm.maxpc8 = atof(*++argv); - - else if (strcmp(4+*argv, "pc16") == 0) - pm.maxpc16 = atof(*++argv); - - else - { - fprintf(stderr, "pngvalid: %s: unknown 'max' option\n", *argv); - exit(1); - } - } - - else - { - fprintf(stderr, "pngvalid: %s: unknown argument\n", *argv); - exit(1); - } - } - - /* If pngvalid is run with no arguments default to a reasonable set of the - * tests. - */ - if (pm.test_standard == 0 && pm.test_size == 0 && pm.test_transform == 0 && - pm.ngammas == 0) - { - pm.test_standard = 1; - pm.test_size = 1; - pm.test_transform = 1; - pm.ngammas = 3U; - } - - if (pm.ngammas > 0 && - pm.test_gamma_threshold == 0 && pm.test_gamma_transform == 0 && - pm.test_gamma_sbit == 0 && pm.test_gamma_strip16 == 0) - { - pm.test_gamma_threshold = 1; - pm.test_gamma_transform = 1; - pm.test_gamma_sbit = 1; - pm.test_gamma_strip16 = 1; - } - - else if (pm.ngammas == 0) - { - /* Nothing to test so turn everything off: */ - pm.test_gamma_threshold = 0; - pm.test_gamma_transform = 0; - pm.test_gamma_sbit = 0; - pm.test_gamma_strip16 = 0; - } - - Try - { - /* Make useful base images */ - make_transform_images(&pm.this); - - /* Perform the standard and gamma tests. */ - if (pm.test_standard) - { - perform_interlace_macro_validation(); - perform_standard_test(&pm); - perform_error_test(&pm); - } - - /* Various oddly sized images: */ - if (pm.test_size) - { - make_size_images(&pm.this); - perform_size_test(&pm); - } - - /* Combinatorial transforms: */ - if (pm.test_transform) - perform_transform_test(&pm); - - if (pm.ngammas > 0) - perform_gamma_test(&pm, pm.this.speed != 0, - summary && !pm.this.speed); - } - - Catch(fault) - { - fprintf(stderr, "pngvalid: test aborted (probably failed in cleanup)\n"); - if (!pm.this.verbose) - { - if (pm.this.error[0] != 0) - fprintf(stderr, "pngvalid: first error: %s\n", pm.this.error); - - fprintf(stderr, "pngvalid: run with -v to see what happened\n"); - } - exit(1); - } - - if (summary && !pm.this.speed) - { - printf("Results using %s point arithmetic %s\n", -#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || PNG_LIBPNG_VER < 10500 - "floating", -#else - "fixed", -#endif - (pm.this.nerrors || (pm.this.treat_warnings_as_errors && - pm.this.nwarnings)) ? "(errors)" : (pm.this.nwarnings ? - "(warnings)" : "(no errors or warnings)") - ); - printf("Allocated memory statistics (in bytes):\n" - "\tread %lu maximum single, %lu peak, %lu total\n" - "\twrite %lu maximum single, %lu peak, %lu total\n", - (unsigned long)pm.this.read_memory_pool.max_max, - (unsigned long)pm.this.read_memory_pool.max_limit, - (unsigned long)pm.this.read_memory_pool.max_total, - (unsigned long)pm.this.write_memory_pool.max_max, - (unsigned long)pm.this.write_memory_pool.max_limit, - (unsigned long)pm.this.write_memory_pool.max_total); - } - - /* Do this here to provoke memory corruption errors in memory not directly - * allocated by libpng - not a complete test, but better than nothing. - */ - store_delete(&pm.this); - - /* Error exit if there are any errors, and maybe if there are any - * warnings. - */ - if (pm.this.nerrors || (pm.this.treat_warnings_as_errors && - pm.this.nwarnings)) - { - if (!pm.this.verbose) - fprintf(stderr, "pngvalid: %s\n", pm.this.error); - - fprintf(stderr, "pngvalid: %d errors, %d warnings\n", pm.this.nerrors, - pm.this.nwarnings); - - exit(1); - } - - /* Success case. */ - if (touch != NULL) - { - FILE *fsuccess = fopen(touch, "wt"); - - if (fsuccess != NULL) - { - int error = 0; - fprintf(fsuccess, "PNG validation succeeded\n"); - fflush(fsuccess); - error = ferror(fsuccess); - - if (fclose(fsuccess) || error) - { - fprintf(stderr, "%s: write failed\n", touch); - exit(1); - } - } - } - - return 0; -} |