1/*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19/**
20 * @file
21 * replaygain tags parsing
22 */
23
24#include <stdint.h>
25#include <stdlib.h>
26#include <string.h>
27
28#include "libavutil/avstring.h"
29#include "libavutil/dict.h"
30#include "libavutil/intreadwrite.h"
31#include "libavutil/mathematics.h"
32#include "libavutil/mem.h"
33#include "libavutil/replaygain.h"
34
35#include "avformat.h"
36#include "replaygain.h"
37
38static int32_t parse_value(const char *value, int32_t min)
39{
40    char *fraction;
41    int  scale = 10000;
42    int32_t mb = 0;
43    int sign   = 1;
44    int db;
45
46    if (!value)
47        return min;
48
49    value += strspn(value, " \t");
50
51    if (*value == '-')
52        sign = -1;
53
54    db = strtol(value, &fraction, 0);
55    if (*fraction++ == '.') {
56        while (av_isdigit(*fraction) && scale) {
57            mb += scale * (*fraction - '0');
58            scale /= 10;
59            fraction++;
60        }
61    }
62
63    if (abs(db) > (INT32_MAX - mb) / 100000)
64        return min;
65
66    return db * 100000 + sign * mb;
67}
68
69int ff_replaygain_export_raw(AVStream *st, int32_t tg, uint32_t tp,
70                             int32_t ag, uint32_t ap)
71{
72    AVPacketSideData *sd, *tmp;
73    AVReplayGain *replaygain;
74    int i;
75
76    if (tg == INT32_MIN && ag == INT32_MIN)
77        return 0;
78
79    for (i = 0; i < st->nb_side_data; i++) {
80        AVPacketSideData *src_sd = &st->side_data[i];
81
82        if (src_sd->type == AV_PKT_DATA_REPLAYGAIN)
83            return 0;
84    }
85
86    replaygain = av_mallocz(sizeof(*replaygain));
87    if (!replaygain)
88        return AVERROR(ENOMEM);
89
90    tmp = av_realloc_array(st->side_data, st->nb_side_data + 1, sizeof(*tmp));
91    if (!tmp) {
92        av_freep(&replaygain);
93        return AVERROR(ENOMEM);
94    }
95    st->side_data = tmp;
96    st->nb_side_data++;
97
98    sd = &st->side_data[st->nb_side_data - 1];
99    sd->type = AV_PKT_DATA_REPLAYGAIN;
100    sd->data = (uint8_t*)replaygain;
101    sd->size = sizeof(*replaygain);
102
103    replaygain->track_gain = tg;
104    replaygain->track_peak = tp;
105    replaygain->album_gain = ag;
106    replaygain->album_peak = ap;
107
108    return 0;
109}
110
111int ff_replaygain_export(AVStream *st, AVDictionary *metadata)
112{
113    const AVDictionaryEntry *tg, *tp, *ag, *ap;
114
115    tg = av_dict_get(metadata, "REPLAYGAIN_TRACK_GAIN", NULL, 0);
116    tp = av_dict_get(metadata, "REPLAYGAIN_TRACK_PEAK", NULL, 0);
117    ag = av_dict_get(metadata, "REPLAYGAIN_ALBUM_GAIN", NULL, 0);
118    ap = av_dict_get(metadata, "REPLAYGAIN_ALBUM_PEAK", NULL, 0);
119
120    return ff_replaygain_export_raw(st,
121                             parse_value(tg ? tg->value : NULL, INT32_MIN),
122                             parse_value(tp ? tp->value : NULL, 0),
123                             parse_value(ag ? ag->value : NULL, INT32_MIN),
124                             parse_value(ap ? ap->value : NULL, 0));
125}
126