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-rw-r--r--demux/cue.c270
1 files changed, 270 insertions, 0 deletions
diff --git a/demux/cue.c b/demux/cue.c
new file mode 100644
index 0000000..104c598
--- /dev/null
+++ b/demux/cue.c
@@ -0,0 +1,270 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv 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.
+ *
+ * mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <inttypes.h>
+
+#include "mpv_talloc.h"
+
+#include "misc/bstr.h"
+#include "common/common.h"
+#include "common/tags.h"
+
+#include "cue.h"
+
+#define SECS_PER_CUE_FRAME (1.0/75.0)
+
+enum cue_command {
+ CUE_ERROR = -1, // not a valid CUE command, or an unknown extension
+ CUE_EMPTY, // line with whitespace only
+ CUE_UNUSED, // valid CUE command, but ignored by this code
+ CUE_FILE,
+ CUE_TRACK,
+ CUE_INDEX,
+ CUE_TITLE,
+ CUE_PERFORMER,
+};
+
+static const struct {
+ enum cue_command command;
+ const char *text;
+} cue_command_strings[] = {
+ { CUE_FILE, "FILE" },
+ { CUE_TRACK, "TRACK" },
+ { CUE_INDEX, "INDEX" },
+ { CUE_TITLE, "TITLE" },
+ { CUE_UNUSED, "CATALOG" },
+ { CUE_UNUSED, "CDTEXTFILE" },
+ { CUE_UNUSED, "FLAGS" },
+ { CUE_UNUSED, "ISRC" },
+ { CUE_PERFORMER, "PERFORMER" },
+ { CUE_UNUSED, "POSTGAP" },
+ { CUE_UNUSED, "PREGAP" },
+ { CUE_UNUSED, "REM" },
+ { CUE_UNUSED, "SONGWRITER" },
+ { CUE_UNUSED, "MESSAGE" },
+ { -1 },
+};
+
+static const uint8_t spaces[] = {' ', '\f', '\n', '\r', '\t', '\v', 0xA0};
+
+static struct bstr lstrip_whitespace(struct bstr data)
+{
+ while (data.len) {
+ bstr rest = data;
+ int code = bstr_decode_utf8(data, &rest);
+ if (code < 0) {
+ // Tolerate Latin1 => probing works (which doesn't convert charsets).
+ code = data.start[0];
+ rest.start += 1;
+ rest.len -= 1;
+ }
+ for (size_t n = 0; n < MP_ARRAY_SIZE(spaces); n++) {
+ if (spaces[n] == code) {
+ data = rest;
+ goto next;
+ }
+ }
+ break;
+ next: ;
+ }
+ return data;
+}
+
+static enum cue_command read_cmd(struct bstr *data, struct bstr *out_params)
+{
+ struct bstr line = bstr_strip_linebreaks(bstr_getline(*data, data));
+ line = lstrip_whitespace(line);
+ if (line.len == 0)
+ return CUE_EMPTY;
+ for (int n = 0; cue_command_strings[n].command != -1; n++) {
+ struct bstr name = bstr0(cue_command_strings[n].text);
+ if (bstr_case_startswith(line, name)) {
+ struct bstr rest = bstr_cut(line, name.len);
+ struct bstr par = lstrip_whitespace(rest);
+ if (rest.len && par.len == rest.len)
+ continue;
+ if (out_params)
+ *out_params = par;
+ return cue_command_strings[n].command;
+ }
+ }
+ return CUE_ERROR;
+}
+
+static bool eat_char(struct bstr *data, char ch)
+{
+ if (data->len && data->start[0] == ch) {
+ *data = bstr_cut(*data, 1);
+ return true;
+ } else {
+ return false;
+ }
+}
+
+static char *read_quoted(void *talloc_ctx, struct bstr *data)
+{
+ *data = lstrip_whitespace(*data);
+ if (!eat_char(data, '"'))
+ return NULL;
+ int end = bstrchr(*data, '"');
+ if (end < 0)
+ return NULL;
+ struct bstr res = bstr_splice(*data, 0, end);
+ *data = bstr_cut(*data, end + 1);
+ return bstrto0(talloc_ctx, res);
+}
+
+static struct bstr strip_quotes(struct bstr data)
+{
+ bstr s = data;
+ if (bstr_eatstart0(&s, "\"") && bstr_eatend0(&s, "\""))
+ return s;
+ return data;
+}
+
+// Read an unsigned decimal integer.
+// Optionally check if it is 2 digit.
+// Return -1 on failure.
+static int read_int(struct bstr *data, bool two_digit)
+{
+ *data = lstrip_whitespace(*data);
+ if (data->len && data->start[0] == '-')
+ return -1;
+ struct bstr s = *data;
+ int res = (int)bstrtoll(s, &s, 10);
+ if (data->len == s.len || (two_digit && data->len - s.len > 2))
+ return -1;
+ *data = s;
+ return res;
+}
+
+static double read_time(struct bstr *data)
+{
+ struct bstr s = *data;
+ bool ok = true;
+ double t1 = read_int(&s, false);
+ ok = eat_char(&s, ':') && ok;
+ double t2 = read_int(&s, true);
+ ok = eat_char(&s, ':') && ok;
+ double t3 = read_int(&s, true);
+ ok = ok && t1 >= 0 && t2 >= 0 && t3 >= 0;
+ return ok ? t1 * 60.0 + t2 + t3 * SECS_PER_CUE_FRAME : 0;
+}
+
+static struct bstr skip_utf8_bom(struct bstr data)
+{
+ return bstr_startswith0(data, "\xEF\xBB\xBF") ? bstr_cut(data, 3) : data;
+}
+
+// Check if the text in data is most likely CUE data. This is used by the
+// demuxer code to check the file type.
+// data is the start of the probed file, possibly cut off at a random point.
+bool mp_probe_cue(struct bstr data)
+{
+ bool valid = false;
+ data = skip_utf8_bom(data);
+ for (;;) {
+ enum cue_command cmd = read_cmd(&data, NULL);
+ // End reached. Since the line was most likely cut off, don't use the
+ // result of the last parsing call.
+ if (data.len == 0)
+ break;
+ if (cmd == CUE_ERROR)
+ return false;
+ if (cmd != CUE_EMPTY)
+ valid = true;
+ }
+ return valid;
+}
+
+struct cue_file *mp_parse_cue(struct bstr data)
+{
+ struct cue_file *f = talloc_zero(NULL, struct cue_file);
+ f->tags = talloc_zero(f, struct mp_tags);
+
+ data = skip_utf8_bom(data);
+
+ char *filename = NULL;
+ // Global metadata, and copied into new tracks.
+ struct cue_track proto_track = {0};
+ struct cue_track *cur_track = NULL;
+
+ while (data.len) {
+ struct bstr param;
+ int cmd = read_cmd(&data, &param);
+ switch (cmd) {
+ case CUE_ERROR:
+ talloc_free(f);
+ return NULL;
+ case CUE_TRACK: {
+ MP_TARRAY_GROW(f, f->tracks, f->num_tracks);
+ f->num_tracks += 1;
+ cur_track = &f->tracks[f->num_tracks - 1];
+ *cur_track = proto_track;
+ cur_track->tags = talloc_zero(f, struct mp_tags);
+ break;
+ }
+ case CUE_TITLE:
+ case CUE_PERFORMER: {
+ static const char *metanames[] = {
+ [CUE_TITLE] = "title",
+ [CUE_PERFORMER] = "performer",
+ };
+ struct mp_tags *tags = cur_track ? cur_track->tags : f->tags;
+ mp_tags_set_bstr(tags, bstr0(metanames[cmd]), strip_quotes(param));
+ break;
+ }
+ case CUE_INDEX: {
+ int type = read_int(&param, true);
+ double time = read_time(&param);
+ if (cur_track) {
+ if (type == 1) {
+ cur_track->start = time;
+ cur_track->filename = filename;
+ } else if (type == 0) {
+ cur_track->pregap_start = time;
+ }
+ }
+ break;
+ }
+ case CUE_FILE:
+ // NOTE: FILE comes before TRACK, so don't use cur_track->filename
+ filename = read_quoted(f, &param);
+ break;
+ }
+ }
+
+ return f;
+}
+
+int mp_check_embedded_cue(struct cue_file *f)
+{
+ char *fn0 = f->tracks[0].filename;
+ for (int n = 1; n < f->num_tracks; n++) {
+ char *fn = f->tracks[n].filename;
+ // both filenames have the same address (including NULL)
+ if (fn0 == fn)
+ continue;
+ // only one filename is NULL, or the strings don't match
+ if (!fn0 || !fn || strcmp(fn0, fn) != 0)
+ return -1;
+ }
+ return 0;
+}
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