Move id3v2 tag writing to a separate file.

Signed-off-by: Diego Biurrun <diego@biurrun.de>

1 files changed, 146 insertions, 0 deletions

diff --git a/libavformat/id3v2enc.c b/libavformat/id3v2enc.c
new file mode 100644
index 0000000000..36c73bfecb
--- /dev/null
+++ b/libavformat/id3v2enc.c
@@ -0,0 +1,146 @@
+/*
+ * ID3v2 header writer
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+
+#include "libavutil/dict.h"
+#include "libavutil/intreadwrite.h"
+#include "avformat.h"
+#include "avio.h"
+#include "id3v2.h"
+
+static void id3v2_put_size(AVFormatContext *s, int size)
+{
+    avio_w8(s->pb, size >> 21 & 0x7f);
+    avio_w8(s->pb, size >> 14 & 0x7f);
+    avio_w8(s->pb, size >> 7  & 0x7f);
+    avio_w8(s->pb, size       & 0x7f);
+}
+
+static int string_is_ascii(const uint8_t *str)
+{
+    while (*str && *str < 128) str++;
+    return !*str;
+}
+
+/**
+ * Write a text frame with one (normal frames) or two (TXXX frames) strings
+ * according to encoding (only UTF-8 or UTF-16+BOM supported).
+ * @return number of bytes written or a negative error code.
+ */
+static int id3v2_put_ttag(AVFormatContext *s, const char *str1, const char *str2,
+                          uint32_t tag, enum ID3v2Encoding enc)
+{
+    int len;
+    uint8_t *pb;
+    int (*put)(AVIOContext*, const char*);
+    AVIOContext *dyn_buf;
+    if (avio_open_dyn_buf(&dyn_buf) < 0)
+        return AVERROR(ENOMEM);
+
+    /* check if the strings are ASCII-only and use UTF16 only if
+     * they're not */
+    if (enc == ID3v2_ENCODING_UTF16BOM && string_is_ascii(str1) &&
+        (!str2 || string_is_ascii(str2)))
+        enc = ID3v2_ENCODING_ISO8859;
+
+    avio_w8(dyn_buf, enc);
+    if (enc == ID3v2_ENCODING_UTF16BOM) {
+        avio_wl16(dyn_buf, 0xFEFF);      /* BOM */
+        put = avio_put_str16le;
+    } else
+        put = avio_put_str;
+
+    put(dyn_buf, str1);
+    if (str2)
+        put(dyn_buf, str2);
+    len = avio_close_dyn_buf(dyn_buf, &pb);
+
+    avio_wb32(s->pb, tag);
+    id3v2_put_size(s, len);
+    avio_wb16(s->pb, 0);
+    avio_write(s->pb, pb, len);
+
+    av_freep(&pb);
+    return len + ID3v2_HEADER_SIZE;
+}
+
+static int id3v2_check_write_tag(AVFormatContext *s, AVDictionaryEntry *t, const char table[][4],
+                                 enum ID3v2Encoding enc)
+{
+    uint32_t tag;
+    int i;
+
+    if (t->key[0] != 'T' || strlen(t->key) != 4)
+        return -1;
+    tag = AV_RB32(t->key);
+    for (i = 0; *table[i]; i++)
+        if (tag == AV_RB32(table[i]))
+            return id3v2_put_ttag(s, t->value, NULL, tag, enc);
+    return -1;
+}
+
+int ff_id3v2_write(struct AVFormatContext *s, int id3v2_version,
+                   const char *magic)
+{
+    int64_t size_pos, cur_pos;
+    AVDictionaryEntry *t = NULL;
+
+    int totlen = 0, enc = id3v2_version == 3 ? ID3v2_ENCODING_UTF16BOM :
+                                               ID3v2_ENCODING_UTF8;
+
+
+    avio_wb32(s->pb, MKBETAG(magic[0], magic[1], magic[2], id3v2_version));
+    avio_w8(s->pb, 0);
+    avio_w8(s->pb, 0); /* flags */
+
+    /* reserve space for size */
+    size_pos = avio_tell(s->pb);
+    avio_wb32(s->pb, 0);
+
+    ff_metadata_conv(&s->metadata, ff_id3v2_34_metadata_conv, NULL);
+    if (id3v2_version == 4)
+        ff_metadata_conv(&s->metadata, ff_id3v2_4_metadata_conv, NULL);
+
+    while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
+        int ret;
+
+        if ((ret = id3v2_check_write_tag(s, t, ff_id3v2_tags, enc)) > 0) {
+            totlen += ret;
+            continue;
+        }
+        if ((ret = id3v2_check_write_tag(s, t, id3v2_version == 3 ?
+                                               ff_id3v2_3_tags : ff_id3v2_4_tags, enc)) > 0) {
+            totlen += ret;
+            continue;
+        }
+
+        /* unknown tag, write as TXXX frame */
+        if ((ret = id3v2_put_ttag(s, t->key, t->value, MKBETAG('T', 'X', 'X', 'X'), enc)) < 0)
+            return ret;
+        totlen += ret;
+    }
+
+    cur_pos = avio_tell(s->pb);
+    avio_seek(s->pb, size_pos, SEEK_SET);
+    id3v2_put_size(s, totlen);
+    avio_seek(s->pb, cur_pos, SEEK_SET);
+    return 0;
+}