write: Improve help text of --writer.

[paraslash.git] / afh_common.c

diff --git a/afh_common.c b/afh_common.c
index cad972d94026eb1f1587fdf7201b752786b801b7..063ae8f0b104ccab15e9f10f637ec34e7783e785 100644 (file)
--- a/afh_common.c
+++ b/afh_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1997-2014 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -15,27 +15,10 @@
 #include "string.h"
 #include "afh.h"
 
-/* The mp3 audio format handler does not need any libs. */
-void mp3_init(struct audio_format_handler *);
-
-#ifdef HAVE_OGGVORBIS
-       void ogg_init(struct audio_format_handler *);
-#endif
-#ifdef HAVE_FAAD
-       void aac_afh_init(struct audio_format_handler *);
-#endif
-#ifdef HAVE_SPEEX
-       void spx_afh_init(struct audio_format_handler *);
-#endif
-#ifdef HAVE_FLAC
-       void flac_afh_init(struct audio_format_handler *);
-#endif
-
-#ifdef HAVE_OPUS
-       void opus_afh_init(struct audio_format_handler *);
-#endif
-
-void wma_afh_init(struct audio_format_handler *);
+typedef void afh_init_func(struct audio_format_handler *);
+/* It does not hurt to declare init functions which are not available. */
+extern afh_init_func mp3_init, ogg_init, aac_afh_init, wma_afh_init,
+       spx_afh_init, flac_afh_init, opus_afh_init;
 
 /** The list of all status items */
 const char *status_item_list[] = {STATUS_ITEM_ARRAY};
@@ -59,13 +42,13 @@ static struct audio_format_handler afl[] = {
        },
        {
                .name = "ogg",
-#ifdef HAVE_OGGVORBIS
+#if defined(HAVE_OGG) && defined(HAVE_VORBIS)
                .init = ogg_init,
 #endif
        },
        {
                .name = "aac",
-#ifdef HAVE_FAAD
+#if defined(HAVE_MP4V2)
                .init = aac_afh_init,
 #endif
        },
@@ -75,19 +58,19 @@ static struct audio_format_handler afl[] = {
        },
        {
                .name = "spx",
-#ifdef HAVE_SPEEX
+#if defined(HAVE_OGG) && defined(HAVE_SPEEX)
                .init = spx_afh_init,
 #endif
        },
        {
                .name = "flac",
-#ifdef HAVE_FLAC
+#if defined(HAVE_OGG) && defined(HAVE_FLAC)
                .init = flac_afh_init,
 #endif
        },
        {
                .name = "opus",
-#ifdef HAVE_OPUS
+#if defined(HAVE_OGG) && defined(HAVE_OPUS)
                .init = opus_afh_init,
 #endif
        },
@@ -118,9 +101,9 @@ void afh_init(void)
 {
        int i;
 
-       PARA_INFO_LOG("supported audio formats: %s\n", AUDIO_FORMAT_HANDLERS);
+       PARA_NOTICE_LOG("supported audio formats: %s\n", AUDIO_FORMAT_HANDLERS);
        FOR_EACH_AUDIO_FORMAT(i) {
-               PARA_NOTICE_LOG("initializing %s handler\n",
+               PARA_INFO_LOG("initializing %s handler\n",
                        audio_format_name(i));
                afl[i].init(&afl[i]);
        }
@@ -230,11 +213,12 @@ success:
 }
 
 /**
- * Deallocate contents of a filled-in ahi structure
+ * Deallocate the contents of an afh_info structure.
  *
  * \param afhi The structure to clear.
  *
- * The given pointer is kept, everything else is freed.
+ * This only frees the memory the various pointer fields of \a afhi point to.
+ * It does *not* free \a afhi itself.
  */
 void clear_afhi(struct afh_info *afhi)
 {
@@ -264,6 +248,12 @@ const char *audio_format_name(int i)
        return afl[i].name;
 }
 
+static inline size_t get_chunk_len(long unsigned chunk_num,
+               const struct afh_info *afhi)
+{
+       return afhi->chunk_table[chunk_num + 1] - afhi->chunk_table[chunk_num];
+}
+
 /**
  * Get one chunk of audio data.
  *
@@ -281,7 +271,28 @@ void afh_get_chunk(long unsigned chunk_num, struct afh_info *afhi,
 {
        size_t pos = afhi->chunk_table[chunk_num];
        *buf = map + pos;
-       *len = afhi->chunk_table[chunk_num + 1] - pos;
+       *len = get_chunk_len(chunk_num, afhi);
+}
+
+/**
+ * Find a suitable start chunk.
+ *
+ * \param approx_chunk_num Upper bound for the chunk number to return.
+ * \param afhi Needed for the chunk table.
+ *
+ * \return The first non-empty chunk <= \a approx_chunk_num.
+ *
+ * \sa \ref afh_get_chunk().
+ */
+int32_t afh_get_start_chunk(int32_t approx_chunk_num,
+               const struct afh_info *afhi)
+{
+       int32_t k;
+
+       for (k = PARA_MAX(0, approx_chunk_num); k >= 0; k--)
+               if (get_chunk_len(k, afhi) > 0)
+                       break;
+       return k;
 }
 
 /**
@@ -356,9 +367,9 @@ unsigned afh_get_afhi_txt(int audio_format_num, struct afh_info *afhi, char **re
                "%s: %s\n" /* format */
                "%s: %dHz\n" /* frequency */
                "%s: %d\n" /* channels */
-               "%s: %lu\n" /* seconds total */
+               "%s: %" PRIu32 "\n" /* seconds total */
                "%s: %lu: %lu\n" /* chunk time */
-               "%s: %lu\n" /* num chunks */
+               "%s: %" PRIu32 "\n" /* num chunks */
                "%s: %s\n" /* techinfo */
                "%s: %s\n" /* artist */
                "%s: %s\n" /* title */
@@ -381,3 +392,31 @@ unsigned afh_get_afhi_txt(int audio_format_num, struct afh_info *afhi, char **re
                status_item_list[SI_COMMENT], afhi->tags.comment? afhi->tags.comment : ""
        );
 }
+
+/**
+ * Create a copy of the given file with altered meta tags.
+ *
+ * \param audio_format_id Specifies the audio format.
+ * \param map The (read-only) memory map of the input file.
+ * \param mapsize The size of the input file in bytes.
+ * \param tags The new tags.
+ * \param output_fd Altered file is created using this file descriptor.
+ * \param filename The name of the temporary output file.
+ *
+ * This calls the ->rewrite_tags method of the audio format handler associated
+ * with \a audio_format_id to create a copy of the memory-mapped file given
+ * by \a map and \a mapsize, but with altered tags according to \a tags. If
+ * the audio format handler for \a audio_format_id lacks this optional method,
+ * the function returns (the paraslash error code of) \p ENOTSUP.
+ *
+ * \return Standard.
+ */
+int afh_rewrite_tags(int audio_format_id, void *map, size_t mapsize,
+               struct taginfo *tags, int output_fd, const char *filename)
+{
+       struct audio_format_handler *afh = afl + audio_format_id;
+
+       if (!afh->rewrite_tags)
+               return -ERRNO_TO_PARA_ERROR(ENOTSUP);
+       return afh->rewrite_tags(map, mapsize, tags, output_fd, filename);
+}