oggfile.c

   1 /*-
   2  * "THE BEER-WARE LICENSE" (Revision 42):
   3  * <tobias.rehbein@web.de> wrote this file. As long as you retain this notice
   4  * you can do whatever you want with this stuff. If we meet some day, and you
   5  * think this stuff is worth it, you can buy me a beer in return.
   6  *                                                              Tobias Rehbein
   7  */
   8
   9 #include <assert.h>
  10 #include <err.h>
  11 #include <iconv.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <sysexits.h>
  15 #include <vorbis/vorbisfile.h>
  16
  17 #include "oggfile.h"
  18
  19 #define SAFE_STRNCPY(dst, src, len)     do {                                    \
  20                                                 strncpy(dst, src, (len)-1);     \
  21                                                 dst[(len)-1] = '\0';            \
  22                                         } while (0)
  23
  24 struct ogg_context {
  25         iconv_t         cd;
  26 };
  27
  28 static int      fill_comments(struct ogg_context *ctx, struct ogg_oggfile *ogg);
  29 static void     do_iconv(struct ogg_context *ctx, char *in, char *out, size_t outlen);
  30
  31 int
  32 ogg_oggfile_create(struct ogg_context *ctx, struct ogg_oggfile *ogg, char *filename)
  33 {
  34         assert(ctx != NULL);
  35         assert(ogg != NULL);
  36         assert(filename != NULL);
  37
  38         SAFE_STRNCPY(ogg->filename, filename, sizeof(ogg->filename));
  39         if (fill_comments(ctx, ogg) != 0)
  40                 return (1);
  41
  42         return (0);
  43 }
  44
  45 static int
  46 fill_comments(struct ogg_context *ctx, struct ogg_oggfile *ogg)
  47 {
  48         OggVorbis_File  ovf;
  49         vorbis_comment *ovc;
  50         char           *key, *value;
  51         int             i;
  52
  53         assert(ctx != NULL);
  54         assert(ogg != NULL);
  55
  56         if (ov_fopen(ogg->filename, &ovf) != 0) {
  57                 warnx("could not open file: %s", ogg->filename);
  58                 return (1);
  59         }
  60         if ((ovc = ov_comment(&ovf, -1)) == NULL) {
  61                 warnx("could not read comments for file: %s", ogg->filename);
  62                 return (1);
  63         }
  64         for (i = 0; i < ovc->comments; i++) {
  65                 value = ovc->user_comments[i];
  66                 key = strsep(&value, "=");
  67                 if (strcasecmp(key, "artist") == 0)
  68                         do_iconv(ctx, value, ogg->artist, sizeof(ogg->artist));
  69                 else if (strcasecmp(key, "album") == 0)
  70                         do_iconv(ctx, value, ogg->album, sizeof(ogg->album));
  71                 else if (strcasecmp(key, "title") == 0)
  72                         do_iconv(ctx, value, ogg->title, sizeof(ogg->title));
  73                 if (ogg->artist == NULL || ogg->album == NULL || ogg->title == NULL) {
  74                         warnx("insufficient comments for file: %s", ogg->filename);
  75                         return (1);
  76                 }
  77         }
  78
  79         if (ov_clear(&ovf) != 0)
  80                 warnx("could not close file: %s", ogg->filename);
  81
  82         return (0);
  83 }
  84
  85 struct ogg_context *
  86 ogg_context_open()
  87 {
  88         struct ogg_context *ctx;
  89         iconv_t         cd;
  90
  91         if ((cd = iconv_open("char", "UTF-8")) == (iconv_t) (-1))
  92                 return (NULL);
  93         if ((ctx = malloc(sizeof(*ctx))) == NULL)
  94                 return (NULL);
  95
  96         ctx->cd = cd;
  97
  98         return (ctx);
  99 }
 100
 101 int
 102 ogg_context_close(struct ogg_context *ctx)
 103 {
 104         assert(ctx != NULL);
 105
 106         if (iconv_close(ctx->cd) == -1)
 107                 return (1);
 108         free(ctx);
 109
 110         return (0);
 111 }
 112
 113 static void
 114 do_iconv(struct ogg_context *ctx, char *in, char *out, size_t outlen)
 115 {
 116         char          **inp;
 117         char          **outp;
 118         size_t          inlen = strlen(in);
 119
 120         assert(ctx != NULL);
 121         assert(in != NULL);
 122         assert(out != NULL);
 123         assert(outlen > 0);
 124
 125         inp = &in;
 126         outp = &out;
 127
 128         if (iconv(ctx->cd, NULL, NULL, outp, &outlen) == (size_t) (-1))
 129                 errx(EX_SOFTWARE, "could not set initial conversion state");
 130
 131         while (inlen > 0) {
 132                 if (iconv(ctx->cd, (const char **)inp, &inlen, outp, &outlen) == (size_t) (-1))
 133                         errx(EX_SOFTWARE, "string conversion failed");
 134         }
 135
 136         *outp[0] = '\0';
 137 }