au_a.c

MIDI解码程序(用VC编写)

/*
    TiMidity++ -- MIDI to WAVE converter and player
    Copyright (C) 1999-2002 Masanao Izumo <[e-mail]>
    Copyright (C) 1995 Tuukka Toivonen <[e-mail]>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    au_a.c

    Functions to output Sun audio file (*.au).
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif /* HAVE_CONFIG_H */
#include <stdio.h>

#ifdef __W32__
#include <stdlib.h>
#include <io.h>
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif /* HAVE_UNISTD_H */

#ifdef STDC_HEADERS
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#elif HAVE_STRINGS_H
#include <strings.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif

#ifdef __FreeBSD__
#include <stdio.h>
#endif

#include "timidity.h"
#include "common.h"
#include "output.h"
#include "controls.h"
#include "instrum.h"
#include "playmidi.h"
#include "readmidi.h"

static int open_output(void); /* 0=success, 1=warning, -1=fatal error */
static void close_output(void);
static int output_data(char *buf, int32 bytes);
static int acntl(int request, void *arg);
static int write_u32(uint32 value);

/* export the playback mode */

#define dpm au_play_mode

PlayMode dpm = {
    8000, PE_MONO|PE_ULAW, PF_PCM_STREAM,
    -1,
    {0,0,0,0,0},
    "Sun audio file", 'u',
    NULL,
    open_output,
    close_output,
    output_data,
    acntl
};

/*************************************************************************/

#define UPDATE_HEADER_STEP (128*1024) /* 128KB */
static uint32 bytes_output, next_bytes;
static int already_warning_lseek;

static int write_u32(uint32 value)
{
    int n;
    value = BE_LONG(value);
    if((n = write(dpm.fd, &value, 4)) == -1)
    {
	ctl->cmsg(CMSG_ERROR, VERB_NORMAL, "%s: write: %s",
		  dpm.name, strerror(errno));
	close_output();
	return -1;
    }
    return n;
}

static int write_str(const char *s)
{
    int n;
    if((n = write(dpm.fd, s, strlen(s))) == -1)
    {
	ctl->cmsg(CMSG_ERROR, VERB_NORMAL, "%s: write: %s",
		  dpm.name, strerror(errno));
	close_output();
	return -1;
    }
    return n;
}

/* Sun Audio File Encoding Tags */
#define AUDIO_FILE_ENCODING_MULAW_8     1      /* 8-bit ISDN u-law */
#define AUDIO_FILE_ENCODING_LINEAR_8    2      /* 8-bit linear PCM */
#define AUDIO_FILE_ENCODING_LINEAR_16   3      /* 16-bit linear PCM */
#define AUDIO_FILE_ENCODING_LINEAR_24   4      /* 24-bit linear PCM */
#define AUDIO_FILE_ENCODING_ALAW_8      27     /* 8-bit ISDN A-law */

static int au_output_open(const char *fname, const char *comment)
{
  int t;

  if(strcmp(fname, "-") == 0) {
    dpm.fd = 1; /* data to stdout */
    if(comment == NULL)
      comment = "(stdout)";
  } else {
    /* Open the audio file */
    dpm.fd = open(fname, FILE_OUTPUT_MODE);
    if(dpm.fd < 0) {
      ctl->cmsg(CMSG_ERROR, VERB_NORMAL, "%s: %s",
		fname, strerror(errno));
      return -1;
    }
    if(comment == NULL)
      comment = fname;
  }

  /* magic */
  if(write_str(".snd") == -1) return -1;

  /* header size */
  if(write_u32((uint32)(24 + strlen(comment))) == -1) return -1;

  /* sample data size */
  if(write_u32((uint32)0xffffffff) == -1) return -1;

  /* audio file encoding */
  if(dpm.encoding & PE_ULAW)
    t = AUDIO_FILE_ENCODING_MULAW_8;
  else if(dpm.encoding & PE_ALAW)
    t = AUDIO_FILE_ENCODING_ALAW_8;
  else if(dpm.encoding & PE_24BIT)
    t = AUDIO_FILE_ENCODING_LINEAR_24;
  else if(dpm.encoding & PE_16BIT)
    t = AUDIO_FILE_ENCODING_LINEAR_16;
  else
    t = AUDIO_FILE_ENCODING_LINEAR_8;
  if(write_u32((uint32)t) == -1) return -1;

  /* sample rate */
  if(write_u32((uint32)dpm.rate) == -1) return -1;

  /* number of channels */
  if(dpm.encoding & PE_MONO) {
    if(write_u32((uint32)1) == -1) return -1;
  } else {
    if(write_u32((uint32)2) == -1) return -1;
  }

  /* comment */
  if(write_str(comment) == -1) return -1;

  bytes_output = 0;
  next_bytes = bytes_output + UPDATE_HEADER_STEP;
  already_warning_lseek = 0;

  return 0;
}

static int auto_au_output_open(const char *input_filename)
{
  char *output_filename = (char *)safe_malloc(strlen(input_filename) + 5);
  char *ext, *p;

  strcpy(output_filename, input_filename);
  if((ext = strrchr(output_filename, '.')) == NULL)
    ext = output_filename + strlen(output_filename);
  else {
    /* strip ".gz" */
    if(strcasecmp(ext, ".gz") == 0) {
      *ext = '\0';
      if((ext = strrchr(output_filename, '.')) == NULL)
	ext = output_filename + strlen(output_filename);
    }
  }

  /* replace '.' and '#' before ext */
  for(p = output_filename; p < ext; p++)
    if(*p == '.' || *p == '#')
      *p = '_';

  if(*ext && isupper(*(ext + 1)))
    strcpy(ext, ".AU");
  else
    strcpy(ext, ".au");
  if(au_output_open(output_filename, input_filename) == -1) {
    free(output_filename);
    return -1;
  }
  if(dpm.name != NULL)
    free(dpm.name);
  dpm.name = output_filename;
  ctl->cmsg(CMSG_INFO, VERB_NORMAL, "Output %s", dpm.name);
  return 0;
}

static int open_output(void)
{
    int include_enc, exclude_enc;

    include_enc = exclude_enc = 0;
    if(dpm.encoding & (PE_16BIT | PE_24BIT))
    {
#ifdef LITTLE_ENDIAN
	include_enc = PE_BYTESWAP;
#else
	exclude_enc = PE_BYTESWAP;
#endif /* LITTLE_ENDIAN */
	include_enc |= PE_SIGNED;
    }
    else if(!(dpm.encoding & (PE_ULAW|PE_ALAW)))
    {
	/* is 8 bit au unsigned ? */
	exclude_enc = PE_SIGNED;
    }

    dpm.encoding = validate_encoding(dpm.encoding, include_enc, exclude_enc);

    if(dpm.name == NULL) {
      dpm.flag |= PF_AUTO_SPLIT_FILE;
      dpm.name = NULL;
    } else {
      dpm.flag &= ~PF_AUTO_SPLIT_FILE;
      if(au_output_open(dpm.name, NULL) == -1)
	return -1;
    }

    return 0;
}


static int update_header(void)
{
    off_t save_point;

    if(already_warning_lseek)
	return 0;

    save_point = lseek(dpm.fd, 0, SEEK_CUR);
    if(save_point == -1 || lseek(dpm.fd, 8, SEEK_SET) == -1)
    {
	ctl->cmsg(CMSG_WARNING, VERB_VERBOSE,
		  "Warning: %s: %s: Can't make valid header",
		  dpm.name, strerror(errno));
	already_warning_lseek = 1;
	return 0;
    }

    if(write_u32(bytes_output) == -1) return -1;
    lseek(dpm.fd, save_point, SEEK_SET);
    ctl->cmsg(CMSG_INFO, VERB_DEBUG,
	      "%s: Update au header (size=%d)", dpm.name, bytes_output);
    return 0;
}


static int output_data(char *buf, int32 bytes)
{
    int n;

    if(dpm.fd == -1)
      return -1;

    while(((n = write(dpm.fd, buf, bytes)) == -1) && errno == EINTR)
	;
    if(n == -1)
    {
	ctl->cmsg(CMSG_ERROR, VERB_NORMAL, "%s: %s",
		  dpm.name, strerror(errno));
	return -1;
    }

    bytes_output += bytes;

#if UPDATE_HEADER_STEP > 0
    if(bytes_output >= next_bytes)
    {
	if(update_header() == -1) return -1;
	next_bytes = bytes_output + UPDATE_HEADER_STEP;
    }
#endif /* UPDATE_HEADER_STEP */
    return n;
}

static void close_output(void)
{
  if(dpm.fd != 1 && /* We don't close stdout */
     dpm.fd != -1) {
    update_header();
    close(dpm.fd);
    dpm.fd = -1;
  }
}

static int acntl(int request, void *arg)
{
  switch(request) {
  case PM_REQ_PLAY_START:
    if(dpm.flag & PF_AUTO_SPLIT_FILE)
      return auto_au_output_open(current_file_info->filename);
    break;
  case PM_REQ_PLAY_END:
    if(dpm.flag & PF_AUTO_SPLIT_FILE) {
      close_output();
      return 0;
    }
    break;
  case PM_REQ_DISCARD:
    return 0;
  }
  return -1;
}