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Diffstat (limited to 'zlib/examples/gzlog.h')
| -rw-r--r-- | zlib/examples/gzlog.h | 91 |
1 files changed, 0 insertions, 91 deletions
diff --git a/zlib/examples/gzlog.h b/zlib/examples/gzlog.h deleted file mode 100644 index 86f0cec..0000000 --- a/zlib/examples/gzlog.h +++ /dev/null @@ -1,91 +0,0 @@ -/* gzlog.h - Copyright (C) 2004, 2008, 2012 Mark Adler, all rights reserved - version 2.2, 14 Aug 2012 - - This software is provided 'as-is', without any express or implied - warranty. In no event will the author be held liable for any damages - arising from the use of this software. - - Permission is granted to anyone to use this software for any purpose, - including commercial applications, and to alter it and redistribute it - freely, subject to the following restrictions: - - 1. The origin of this software must not be misrepresented; you must not - claim that you wrote the original software. If you use this software - in a product, an acknowledgment in the product documentation would be - appreciated but is not required. - 2. Altered source versions must be plainly marked as such, and must not be - misrepresented as being the original software. - 3. This notice may not be removed or altered from any source distribution. - - Mark Adler madler@alumni.caltech.edu - */ - -/* Version History: - 1.0 26 Nov 2004 First version - 2.0 25 Apr 2008 Complete redesign for recovery of interrupted operations - Interface changed slightly in that now path is a prefix - Compression now occurs as needed during gzlog_write() - gzlog_write() now always leaves the log file as valid gzip - 2.1 8 Jul 2012 Fix argument checks in gzlog_compress() and gzlog_write() - 2.2 14 Aug 2012 Clean up signed comparisons - */ - -/* - The gzlog object allows writing short messages to a gzipped log file, - opening the log file locked for small bursts, and then closing it. The log - object works by appending stored (uncompressed) data to the gzip file until - 1 MB has been accumulated. At that time, the stored data is compressed, and - replaces the uncompressed data in the file. The log file is truncated to - its new size at that time. After each write operation, the log file is a - valid gzip file that can decompressed to recover what was written. - - The gzlog operations can be interupted at any point due to an application or - system crash, and the log file will be recovered the next time the log is - opened with gzlog_open(). - */ - -#ifndef GZLOG_H -#define GZLOG_H - -/* gzlog object type */ -typedef void gzlog; - -/* Open a gzlog object, creating the log file if it does not exist. Return - NULL on error. Note that gzlog_open() could take a while to complete if it - has to wait to verify that a lock is stale (possibly for five minutes), or - if there is significant contention with other instantiations of this object - when locking the resource. path is the prefix of the file names created by - this object. If path is "foo", then the log file will be "foo.gz", and - other auxiliary files will be created and destroyed during the process: - "foo.dict" for a compression dictionary, "foo.temp" for a temporary (next) - dictionary, "foo.add" for data being added or compressed, "foo.lock" for the - lock file, and "foo.repairs" to log recovery operations performed due to - interrupted gzlog operations. A gzlog_open() followed by a gzlog_close() - will recover a previously interrupted operation, if any. */ -gzlog *gzlog_open(char *path); - -/* Write to a gzlog object. Return zero on success, -1 if there is a file i/o - error on any of the gzlog files (this should not happen if gzlog_open() - succeeded, unless the device has run out of space or leftover auxiliary - files have permissions or ownership that prevent their use), -2 if there is - a memory allocation failure, or -3 if the log argument is invalid (e.g. if - it was not created by gzlog_open()). This function will write data to the - file uncompressed, until 1 MB has been accumulated, at which time that data - will be compressed. The log file will be a valid gzip file upon successful - return. */ -int gzlog_write(gzlog *log, void *data, size_t len); - -/* Force compression of any uncompressed data in the log. This should be used - sparingly, if at all. The main application would be when a log file will - not be appended to again. If this is used to compress frequently while - appending, it will both significantly increase the execution time and - reduce the compression ratio. The return codes are the same as for - gzlog_write(). */ -int gzlog_compress(gzlog *log); - -/* Close a gzlog object. Return zero on success, -3 if the log argument is - invalid. The log object is freed, and so cannot be referenced again. */ -int gzlog_close(gzlog *log); - -#endif |