From 16ad77b357ebbe74a7bc9568904c328a2722651e Mon Sep 17 00:00:00 2001 From: Michael Karcher Date: Fri, 21 Oct 2011 23:32:32 +0200 Subject: Move id3v2 tag writing to a separate file. Signed-off-by: Diego Biurrun --- libavformat/id3v2enc.c | 146 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 146 insertions(+) create mode 100644 libavformat/id3v2enc.c (limited to 'libavformat/id3v2enc.c') 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 + +#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; +} -- cgit v1.2.3