MCIWave.cpp

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/*  Project nGenEx
        Destroyer Studios LLC
        Copyright © 1997-2004. All Rights Reserved.

        SUBSYSTEM:    nGenEx.lib
        FILE:         MCIWave.cpp
        AUTHOR:       John DiCamillo


        OVERVIEW
        ========
        MCI Wave Output stuff
*/

#include "MemDebug.h"
#include "Types.h"

// +----------------------------------------------------------------------+

void  Print(const char* fmt, ...);

// +----------------------------------------------------------------------+

const int MCI_MAX_STR = 128;
static char       ret_str[MCI_MAX_STR];
static char       err_str[MCI_MAX_STR];
static MCIERROR   mci_err;
static MMRESULT   wav_err;
extern HWND       hwndApp;

static int mci_send_string(const char* cmd_str)
{
        mci_err = mciSendString(cmd_str, ret_str, sizeof(ret_str), hwndApp);
        if (mci_err) {
                if (mciGetErrorString(mci_err, err_str, sizeof(err_str)))
                Print("Error (%s): '%s'\n", cmd_str, err_str);
                else
                Print("Error (%s): %d - UNKNOWN\n", cmd_str, mci_err);
                return 0;   
        }

        return 1;
}

// +--------------------------------------------------------------------+

static void print_wav_error()
{
        waveOutGetErrorText(wav_err, err_str, MCI_MAX_STR);
        Print(err_str);
}

// +--------------------------------------------------------------------+

int load_wave_file(const char* fname, LPWAVEHDR hdr, LPWAVEFORMATEX format)
{
        HMMIO       hmmio;            /* file handle for open file */ 
        MMCKINFO    mmckinfoParent;   /* parent chunk information structure */ 
        MMCKINFO    mmckinfoSubchunk; /* subchunk information structure    */ 
        DWORD       dwFmtSize;        /* size of "fmt" chunk               */ 
        DWORD       dwDataSize;       /* size of "data" chunk              */ 

        /* 
        * Open the given file for reading with buffered I/O 
        * using the default internal buffer. 
        */ 
        hmmio = mmioOpen((LPSTR) fname, NULL, MMIO_READ | MMIO_ALLOCBUF); 

        if (hmmio == NULL) {
                Print("load_wave_file(): '%s' - Failed to open file.\n", fname); 
                return 0;
        }

        /* 
        * Locate a "RIFF" chunk with a "WAVE" form type 
        * to make sure the file is a WAVE file. 
        */ 
        mmckinfoParent.fccType = mmioFOURCC('W', 'A', 'V', 'E'); 
        if (mmioDescend(hmmio, (LPMMCKINFO) &mmckinfoParent, NULL, MMIO_FINDRIFF)) { 
                Print("load_wave_file(): '%s' - This is not a WAVE file.\n", fname);
                mmioClose(hmmio, 0);
                return 0;
        }

        /* 
        * Find the "fmt " chunk (form type "fmt "); it must be 
        * a subchunk of the "RIFF" parent chunk. 
        */ 
        mmckinfoSubchunk.ckid = mmioFOURCC('f', 'm', 't', ' '); 
        if (mmioDescend(hmmio, &mmckinfoSubchunk, &mmckinfoParent, MMIO_FINDCHUNK)) { 
                Print("load_wave_file(): '%s' - WAVE file has no \"fmt\" chunk\n", fname);
                mmioClose(hmmio, 0);
                return 0;
        }

        /* 
        * Get the size of the "fmt " chunk--allocate and lock memory for it. 
        */ 
        dwFmtSize = mmckinfoSubchunk.cksize; 

        /* Read the "fmt " chunk. */ 
        if (mmioRead(hmmio, (HPSTR) format, dwFmtSize) != (LRESULT)dwFmtSize) {
                Print("load_wave_file(): '%s' - Failed to read format chunk.\n", fname);
                mmioClose(hmmio, 0);
                return 0;
        }

        /* Ascend out of the "fmt " subchunk. */ 
        mmioAscend(hmmio, &mmckinfoSubchunk, 0); 

        /* 
        * Find the data subchunk. The current file position 
        * should be at the beginning of the data chunk. 
        */ 
        mmckinfoSubchunk.ckid = mmioFOURCC('d', 'a', 't', 'a'); 
        if (mmioDescend(hmmio, &mmckinfoSubchunk, &mmckinfoParent, MMIO_FINDCHUNK)) {
                Print("load_wave_file(): '%s' - WAVE file has no data chunk.\n", fname);
                mmioClose(hmmio, 0); 
                return 0; 
        } 

        /* Get the size of the data subchunk. */ 
        dwDataSize = mmckinfoSubchunk.cksize;
        if (dwDataSize == 0L) {
                Print("load_wave_file(): '%s' - The data chunk contains no data.\n", fname);
                mmioClose(hmmio, 0);
                return 0;
        }

        // allocate the data block:
        hdr->lpData = (LPSTR) new(__FILE__,__LINE__) BYTE[dwDataSize];
        hdr->dwBufferLength = dwDataSize;

        /* Read the waveform data subchunk. */
        if (mmioRead(hmmio, (HPSTR) hdr->lpData, dwDataSize) != (LRESULT)dwDataSize) {
                Print("load_wave_file(): '%s' - Failed to read data chunk.\n", fname);
                mmioClose(hmmio, 0);
                return 0;
        }

        /* Close the file. */
        mmioClose(hmmio, 0);

        return 1;
}

// +--------------------------------------------------------------------+

void delete_wave_file(LPWAVEHDR hdr, LPWAVEFORMATEX format)
{
        if (hdr) {
                delete hdr->lpData;
                hdr->lpData = 0;
        }
}