lsmp3.c

/* lsmp3.c *************************************** UPDATED: 1999-04-08 23:38 TT
 *
 * Copyright   : (C) 1999 Tormod Tjaberg
 * Author      : Tormod Tjaberg (tjaberg@online.no)
 * Ripper      : Zeograd (zeograd@caramail.com)
 * Created     : 1999-02-14
 * Ripped      : around 1999-11-21
 * Description : Display the ID3 tag v1.0 & v1.1 of an MP3 file
 * Author      : Tormod Tjaberg 
 *
 * Note:
 * . Were shamelessly ripped from zeograd to know MP3 length for Hu-Go!
 *
 * . Genres were taken from Winamp 2.091 using doctored files :)
 *
 * . TAG code info is based on ID3-Tag Specification V1.1 by Michael Mutschler
 *   http://tick.informatik.uni-stuttgart.de/~mutschml/MP3ext/ID3-Tag.html
 *
 * . The MP3 header documentation is gleaned from several sources. 
 *   I could not find a definitive source which explained all versions.
 *
 *   . The "Private Life Of MP3 frames" 
 *     <http://www.id3.org>
 *
 *   . The Perl script "mp3tag.pm" by Peter D. Kovacs sent to me by Ole
 *     <http://www.egr.uri.edu/~kovacsp>
 *
 *   . A lot of the header decoder info is from Oliver Fromme's "mp3asm"
 *     <http://mpg.123.org>
 *
 * Changes:
 * 1999-04-08: 1.17: Exit properly after displaying "usage" text
 * 1999-03-07: 1.16: Cosmetic change
 * 1999-02-26: 1.15: Even more info, restructured layout
 * 1999-02-26: 1.10: Support for MP3 frame info
 * 1999-02-14: 1.00: Initial release, TAG's only
 */
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <ctype.h>
#include <limits.h>
#include <assert.h>

#define PROGRAM_NAME "lsmp3"
#define PROGRAM_VER  "1.17"

#define ID3_TAG_LEN  128
#define TAG_LEN      3
#define SONGNAME_LEN 30
#define ARTIST_LEN   30
#define ALBUM_LEN    30
#define YEAR_LEN     4
#define COMMENT_LEN  30
#define NUM_GENRE    148
#define FRAME_SIZ    2048

/* Clever little option mimic wildcard expansion from
 * shell ONLY available with the Zortech compiler ver 3.0x and upwards
 */
#if defined(__ZTC__)
extern int _cdecl __wildcard;
int *__wild = &__wildcard;
#endif

/* Needs to be at least 4 bytes */
typedef unsigned long uint4;

/*
 *   1st index:  0 = "MPEG 1.0",   1 = "MPEG 2.0"
 *   2nd index:  0 unused,   1 = "Layer 3",   2 = "Layer 2",   3 = "Layer 1"
 *   3rd index:  BitRateIdx index from frame header
 */
int KbPerSecTab[2][4][16] = {
  {
   {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
   {0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320},
   {0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384},
   {0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448}
   },
  {
   {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
   {0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160},
   {0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160},
   {0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256}
   }
};

unsigned int FrqTab[] = { 44100, 48000, 32000, 22050, 24000, 16000, 11025 };
char *EmphasisTbl[] = { "none", "50/15ms", "unknown", "CCITTj.17" };

char
fBufferEmpty (char *pBuffer)
{
  if (pBuffer == NULL)
    return 1;

  for (; isspace (*pBuffer) && *pBuffer != '\0'; pBuffer++)
    ;

  if (*pBuffer == '\0')
    return 1;
  else
    return 0;
}


float
MP3_length (char *argv)
{
  FILE *fp;
  char *pFileSpec;
  long FilePos;
  char TagStr[TAG_LEN + 1];
  char SongNameStr[SONGNAME_LEN + 1];
  char ArtistStr[ARTIST_LEN + 1];
  char AlbumStr[ALBUM_LEN + 1];
  char YearStr[YEAR_LEN + 1];
  char CommentStr[COMMENT_LEN + 1];
  unsigned char *pBuf;
  unsigned char *pBufTrav;
  unsigned char *pBufEnd;
  int Layer;
  int BitRateIdx;
  int Frq;
  int MajorVer;
  int MinorVer = 0;
  int KbPerSec = 0;
  int Mode;
  int Emphasis;
  int fCRC = 0;
  int fPadding = 0;
  int fPrivate = 0;
  int fCopyright = 0;
  int fOriginal = 0;
  uint4 Head;
  long n;
/*   long Length; */
  long TotTime = 0;
  long TotLength = 0;
  long TotNum = 0;
  int i;

  /* Add a few extra bytes so we may overstep our buffer */
  if ((pBuf = (unsigned char *) malloc (FRAME_SIZ + 8)) == NULL)
    return 0;

  {
    pFileSpec = argv;

    if ((fp = fopen (pFileSpec, "rb")) == NULL)
      return 0;

    /* Determine if this is an MP3 */
    n = fread (pBuf, sizeof (char), FRAME_SIZ, fp);

    if (n <= 128)
      {
	/* Too short */
	fclose (fp);
	return 0;
      }

    /* Use KbPerSec as a sentinel */
    for (KbPerSec = -1, pBufTrav = pBuf, pBufEnd = pBuf + n;
	 pBufTrav != pBufEnd; pBufTrav++)
      {
	/* Search for the sync 12 or 11 bits set !, I'm assuming that
	 * the alignment could be anything.
	 */
	if (pBufTrav[0] == 0xff && (pBufTrav[1] & 0xe0) == 0xe0)
	  {
	    Head = (uint4) pBufTrav[0] << 24 |
	      (uint4) pBufTrav[1] << 16 |
	      (uint4) pBufTrav[2] << 8 | (uint4) pBufTrav[3];

	    /* Test code from mp3asm */
	    if ((Head & 0x0c00) == 0x0c00 || !(Head & 0x060000))
	      return 0;

	    if ((BitRateIdx = (0x0f & Head >> 12)) == 0)
	      return 0;

	    if ((Layer = 4 - (0x03 & Head >> 17)) > 3)
	      return 0;

	    if (Head & 0x00100000)
	      {
		if (Head & 0x00080000)
		  {		/* MPEG 1.0 */
		    MajorVer = 1;
		    Frq = FrqTab[0x03 & (Head >> 10)];
		  }
		else
		  {		/* MPEG 2.0 */
		    MajorVer = 2;
		    Frq = FrqTab[3 + (0x03 & (Head >> 10))];
		  }
		MinorVer = 0;
	      }
	    else
	      {			/* "MPEG 2.5" */
		Frq = FrqTab[6];
		MajorVer = 2;
		MinorVer = 5;
	      }

	    KbPerSec = KbPerSecTab[MajorVer - 1][4 - Layer][BitRateIdx];

	    Mode = 0x03 & (Head >> 6);

	    /* If the protecion bit is NOT set then a 16bit CRC follows
	     * the frame header
	     */
	    if (!(Head & 0x10000))
	      fCRC = 1;

	    if (Head & 0x0200)
	      fPadding = 1;

	    if (Head & 0x100)
	      fPrivate = 1;

	    if (Head & 0x08)
	      fCopyright = 1;

	    if (Head & 0x04)
	      fOriginal = 1;

	    Emphasis = Head & 0x3;

	    break;
	  }
      }

    /* Is this a valid MP3 file ? */
    if (KbPerSec == -1)
      {
	fclose (fp);
	return 0;
      }

    /* Seek to the end of the file */
    fseek (fp, 0, SEEK_END);
    FilePos = ftell (fp);

    return (float) FilePos / ((long) KbPerSec * 125);

/*
      TotTime += Length;
      TotLength += FilePos;
      TotNum++;


      printf("File   : %s (%ldK, %d:%02ds)\n",
              pFileSpec, FilePos / 1024, (int) (Length / 60), (int) (Length - ((Length / 60) * 60)));
      printf("Info   : MPEG ver %d.%d layer %d, freq %uHz, KBit/s %d, %s\n", 
              MajorVer, MinorVer, Layer, Frq, KbPerSec, Mode == 3 ? "Mono" : "Stereo");
*/
#if 0
    /* Just in case you need it :) */
    printf
      ("Details: Private=%s CRC's=%s Copyright=%s Original=%s Emphasis=%s\n",
       fPrivate ? "Yes" : "No", fCRC ? "Yes" : "No",
       fCopyright ? "Yes" : "No", fOriginal ? "Yes" : "No",
       EmphasisTbl[Emphasis]);
#endif

    if (pBuf[0] == 'I' && pBuf[1] == 'D' && pBuf[2] == '3')
      {
	fclose (fp);
	return 0;
      }

    /* Look for the TAG ID go backwards */
    if (FilePos < ID3_TAG_LEN)
      {
	fclose (fp);
	return 0;
      }

    /* Position ourselves in front of the TAG */
    fseek (fp, -ID3_TAG_LEN, SEEK_END);

    /* Start with a clean slate */
    TagStr[0] = 0;
    if (fread (TagStr, sizeof (char), TAG_LEN, fp) != TAG_LEN)
      {
	fclose (fp);
	return 0;
      }

    if (!(TagStr[0] == 'T' && TagStr[1] == 'A' && TagStr[2] == 'G'))
      {
	fclose (fp);
	return 0;
      }

    /* Read in all the fields and null terminate them */
    fread (SongNameStr, sizeof (char), SONGNAME_LEN, fp);
    SongNameStr[SONGNAME_LEN] = 0;
    fread (ArtistStr, sizeof (char), ARTIST_LEN, fp);
    ArtistStr[ARTIST_LEN] = 0;
    fread (AlbumStr, sizeof (char), ALBUM_LEN, fp);
    AlbumStr[ALBUM_LEN] = 0;
    fread (YearStr, sizeof (char), YEAR_LEN, fp);
    YearStr[YEAR_LEN] = 0;
    fread (CommentStr, sizeof (char), COMMENT_LEN, fp);
    CommentStr[COMMENT_LEN] = 0;

    /* Finally get the Genre */
    i = getc (fp);

    fclose (fp);

    if (i == EOF)
      return 0;

    /* All stuff is read in, display it, now instead of storing
     * 0's a lot of people hve stored space, handle it
     */
/*
      if (!fBufferEmpty(ArtistStr))
         printf("Artist : %s\n", ArtistStr);

      if (!fBufferEmpty(SongNameStr))
         printf("Title  : %s\n", SongNameStr);

      if (!fBufferEmpty(AlbumStr))
         printf("Album  : %s\n", AlbumStr);

      if (!fBufferEmpty(YearStr))
         printf("Year   : %s\n", YearStr);

      if (!fBufferEmpty(CommentStr))
         printf("Comment: %s\n", CommentStr);
*/

    /* Special ID3 ver 1.1 addition */

/*
      if (CommentStr[COMMENT_LEN - 2] == 0 && 
          CommentStr[COMMENT_LEN - 1] != 0)
         printf("Track  : %d\n", CommentStr[COMMENT_LEN - 1]);
*/

    /* 255 means unused */

/*
      if (i != 255)
      {
         if (i >= 0 && i < NUM_GENRE)
            printf("Genre  : %s\n", pGenreTbl[i]);
         else
            printf("Genre  : unknown genre\n");
      }
*/
    putchar ('\n');
  }

  if (pBuf != NULL)
    free (pBuf);

  if (TotNum > 1)
    printf ("Total  : %ld files %ldK %d:%02ds\n", TotNum, TotLength / 1024,
	    (int) (TotTime / 60), (int) (TotTime - ((TotTime / 60) * 60)));

  return 0;
}