GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavfilter/graphparser.c Lines: 194 332 58.4 %
Date: 2020-09-25 23:16:12 Branches: 105 194 54.1 %

Line Branch Exec Source
1
/*
2
 * filter graph parser
3
 * Copyright (c) 2008 Vitor Sessak
4
 * Copyright (c) 2007 Bobby Bingham
5
 *
6
 * This file is part of FFmpeg.
7
 *
8
 * FFmpeg is free software; you can redistribute it and/or
9
 * modify it under the terms of the GNU Lesser General Public
10
 * License as published by the Free Software Foundation; either
11
 * version 2.1 of the License, or (at your option) any later version.
12
 *
13
 * FFmpeg is distributed in the hope that it will be useful,
14
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16
 * Lesser General Public License for more details.
17
 *
18
 * You should have received a copy of the GNU Lesser General Public
19
 * License along with FFmpeg; if not, write to the Free Software
20
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21
 */
22
23
#include <string.h>
24
#include <stdio.h>
25
26
#include "libavutil/avstring.h"
27
#include "libavutil/mem.h"
28
#include "avfilter.h"
29
30
#define WHITESPACES " \n\t\r"
31
32
/**
33
 * Link two filters together.
34
 *
35
 * @see avfilter_link()
36
 */
37
5744
static int link_filter(AVFilterContext *src, int srcpad,
38
                       AVFilterContext *dst, int dstpad,
39
                       void *log_ctx)
40
{
41
    int ret;
42
5744
    if ((ret = avfilter_link(src, srcpad, dst, dstpad))) {
43
        av_log(log_ctx, AV_LOG_ERROR,
44
               "Cannot create the link %s:%d -> %s:%d\n",
45
               src->filter->name, srcpad, dst->filter->name, dstpad);
46
        return ret;
47
    }
48
49
5744
    return 0;
50
}
51
52
/**
53
 * Parse the name of a link, which has the format "[linkname]".
54
 *
55
 * @return a pointer (that need to be freed after use) to the name
56
 * between parenthesis
57
 */
58
375
static char *parse_link_name(const char **buf, void *log_ctx)
59
{
60
375
    const char *start = *buf;
61
    char *name;
62
375
    (*buf)++;
63
64
375
    name = av_get_token(buf, "]");
65
375
    if (!name)
66
        return NULL;
67
68
375
    if (!name[0]) {
69
        av_log(log_ctx, AV_LOG_ERROR,
70
               "Bad (empty?) label found in the following: \"%s\".\n", start);
71
        goto fail;
72
    }
73
74
375
    if (**buf != ']') {
75
        av_log(log_ctx, AV_LOG_ERROR,
76
               "Mismatched '[' found in the following: \"%s\".\n", start);
77
    fail:
78
        av_freep(&name);
79
        return NULL;
80
    }
81
375
    (*buf)++;
82
83
375
    return name;
84
}
85
86
/**
87
 * Create an instance of a filter, initialize and insert it in the
88
 * filtergraph in *ctx.
89
 *
90
 * @param filt_ctx put here a filter context in case of successful creation and configuration, NULL otherwise.
91
 * @param ctx the filtergraph context
92
 * @param index an index which is supposed to be unique for each filter instance added to the filtergraph
93
 * @param name the name of the filter to create, can be filter name or filter_name\@id as instance name
94
 * @param args the arguments provided to the filter during its initialization
95
 * @param log_ctx the log context to use
96
 * @return >= 0 in case of success, a negative AVERROR code otherwise
97
 */
98
11647
static int create_filter(AVFilterContext **filt_ctx, AVFilterGraph *ctx, int index,
99
                         const char *name, const char *args, void *log_ctx)
100
{
101
    const AVFilter *filt;
102
    char name2[30];
103
11647
    const char *inst_name = NULL, *filt_name = NULL;
104
11647
    char *tmp_args = NULL;
105
    int ret, k;
106
107
11647
    av_strlcpy(name2, name, sizeof(name2));
108
109
77093
    for (k = 0; name2[k]; k++) {
110

65446
        if (name2[k] == '@' && name[k+1]) {
111
            name2[k] = 0;
112
            inst_name = name;
113
            filt_name = name2;
114
            break;
115
        }
116
    }
117
118
11647
    if (!inst_name) {
119
11647
        snprintf(name2, sizeof(name2), "Parsed_%s_%d", name, index);
120
11647
        inst_name = name2;
121
11647
        filt_name = name;
122
    }
123
124
11647
    filt = avfilter_get_by_name(filt_name);
125
126
11647
    if (!filt) {
127
        av_log(log_ctx, AV_LOG_ERROR,
128
               "No such filter: '%s'\n", filt_name);
129
        return AVERROR(EINVAL);
130
    }
131
132
11647
    *filt_ctx = avfilter_graph_alloc_filter(ctx, filt, inst_name);
133
11647
    if (!*filt_ctx) {
134
        av_log(log_ctx, AV_LOG_ERROR,
135
               "Error creating filter '%s'\n", filt_name);
136
        return AVERROR(ENOMEM);
137
    }
138
139

11647
    if (!strcmp(filt_name, "scale") && (!args || !strstr(args, "flags")) &&
140
2563
        ctx->scale_sws_opts) {
141
2563
        if (args) {
142
201
            tmp_args = av_asprintf("%s:%s",
143
                    args, ctx->scale_sws_opts);
144
201
            if (!tmp_args)
145
                return AVERROR(ENOMEM);
146
201
            args = tmp_args;
147
        } else
148
2362
            args = ctx->scale_sws_opts;
149
    }
150
151
11647
    ret = avfilter_init_str(*filt_ctx, args);
152
11647
    if (ret < 0) {
153
        av_log(log_ctx, AV_LOG_ERROR,
154
               "Error initializing filter '%s'", filt_name);
155
        if (args)
156
            av_log(log_ctx, AV_LOG_ERROR, " with args '%s'", args);
157
        av_log(log_ctx, AV_LOG_ERROR, "\n");
158
        avfilter_free(*filt_ctx);
159
        *filt_ctx = NULL;
160
    }
161
162
11647
    av_free(tmp_args);
163
11647
    return ret;
164
}
165
166
/**
167
 * Parse a string of the form FILTER_NAME[=PARAMS], and create a
168
 * corresponding filter instance which is added to graph with
169
 * create_filter().
170
 *
171
 * @param filt_ctx Pointer that is set to the created and configured filter
172
 *                 context on success, set to NULL on failure.
173
 * @param filt_ctx put here a pointer to the created filter context on
174
 * success, NULL otherwise
175
 * @param buf pointer to the buffer to parse, *buf will be updated to
176
 * point to the char next after the parsed string
177
 * @param index an index which is assigned to the created filter
178
 * instance, and which is supposed to be unique for each filter
179
 * instance added to the filtergraph
180
 * @return >= 0 in case of success, a negative AVERROR code otherwise
181
 */
182
11647
static int parse_filter(AVFilterContext **filt_ctx, const char **buf, AVFilterGraph *graph,
183
                        int index, void *log_ctx)
184
{
185
11647
    char *opts = NULL;
186
11647
    char *name = av_get_token(buf, "=,;[");
187
    int ret;
188
189
11647
    if (!name)
190
        return AVERROR(ENOMEM);
191
192
11647
    if (**buf == '=') {
193
6080
        (*buf)++;
194
6080
        opts = av_get_token(buf, "[],;");
195
6080
        if (!opts) {
196
            av_free(name);
197
            return AVERROR(ENOMEM);
198
        }
199
    }
200
201
11647
    ret = create_filter(filt_ctx, graph, index, name, opts, log_ctx);
202
11647
    av_free(name);
203
11647
    av_free(opts);
204
11647
    return ret;
205
}
206
207
AVFilterInOut *avfilter_inout_alloc(void)
208
{
209
    return av_mallocz(sizeof(AVFilterInOut));
210
}
211
212
17693
void avfilter_inout_free(AVFilterInOut **inout)
213
{
214
29500
    while (*inout) {
215
11807
        AVFilterInOut *next = (*inout)->next;
216
11807
        av_freep(&(*inout)->name);
217
11807
        av_freep(inout);
218
11807
        *inout = next;
219
    }
220
17693
}
221
222
375
static AVFilterInOut *extract_inout(const char *label, AVFilterInOut **links)
223
{
224
    AVFilterInOut *ret;
225
226

564
    while (*links && (!(*links)->name || strcmp((*links)->name, label)))
227
189
        links = &((*links)->next);
228
229
375
    ret = *links;
230
231
375
    if (ret) {
232
156
        *links = ret->next;
233
156
        ret->next = NULL;
234
    }
235
236
375
    return ret;
237
}
238
239
11882
static void insert_inout(AVFilterInOut **inouts, AVFilterInOut *element)
240
{
241
11882
    element->next = *inouts;
242
11882
    *inouts = element;
243
11882
}
244
245
23595
static void append_inout(AVFilterInOut **inouts, AVFilterInOut **element)
246
{
247

23710
    while (*inouts && (*inouts)->next)
248
115
        inouts = &((*inouts)->next);
249
250
23595
    if (!*inouts)
251
23367
        *inouts = *element;
252
    else
253
228
        (*inouts)->next = *element;
254
23595
    *element = NULL;
255
23595
}
256
257
11647
static int link_filter_inouts(AVFilterContext *filt_ctx,
258
                              AVFilterInOut **curr_inputs,
259
                              AVFilterInOut **open_inputs, void *log_ctx)
260
{
261
    int pad, ret;
262
263
23255
    for (pad = 0; pad < filt_ctx->nb_inputs; pad++) {
264
11608
        AVFilterInOut *p = *curr_inputs;
265
266
11608
        if (p) {
267
5768
            *curr_inputs = (*curr_inputs)->next;
268
5768
            p->next = NULL;
269
5840
        } else if (!(p = av_mallocz(sizeof(*p))))
270
            return AVERROR(ENOMEM);
271
272
11608
        if (p->filter_ctx) {
273
5744
            ret = link_filter(p->filter_ctx, p->pad_idx, filt_ctx, pad, log_ctx);
274
5744
            av_freep(&p->name);
275
5744
            av_freep(&p);
276
5744
            if (ret < 0)
277
                return ret;
278
        } else {
279
5864
            p->filter_ctx = filt_ctx;
280
5864
            p->pad_idx = pad;
281
5864
            append_inout(open_inputs, &p);
282
        }
283
    }
284
285
11647
    if (*curr_inputs) {
286
        av_log(log_ctx, AV_LOG_ERROR,
287
               "Too many inputs specified for the \"%s\" filter.\n",
288
               filt_ctx->filter->name);
289
        return AVERROR(EINVAL);
290
    }
291
292
11647
    pad = filt_ctx->nb_outputs;
293
23334
    while (pad--) {
294
11687
        AVFilterInOut *currlinkn = av_mallocz(sizeof(AVFilterInOut));
295
11687
        if (!currlinkn)
296
            return AVERROR(ENOMEM);
297
11687
        currlinkn->filter_ctx  = filt_ctx;
298
11687
        currlinkn->pad_idx = pad;
299
11687
        insert_inout(curr_inputs, currlinkn);
300
    }
301
302
11647
    return 0;
303
}
304
305
11647
static int parse_inputs(const char **buf, AVFilterInOut **curr_inputs,
306
                        AVFilterInOut **open_outputs, void *log_ctx)
307
{
308
11647
    AVFilterInOut *parsed_inputs = NULL;
309
11647
    int pad = 0;
310
311
11827
    while (**buf == '[') {
312
180
        char *name = parse_link_name(buf, log_ctx);
313
        AVFilterInOut *match;
314
315
180
        if (!name) {
316
            avfilter_inout_free(&parsed_inputs);
317
            return AVERROR(EINVAL);
318
        }
319
320
        /* First check if the label is not in the open_outputs list */
321
180
        match = extract_inout(name, open_outputs);
322
323
180
        if (match) {
324
156
            av_free(name);
325
        } else {
326
            /* Not in the list, so add it as an input */
327
24
            if (!(match = av_mallocz(sizeof(AVFilterInOut)))) {
328
                avfilter_inout_free(&parsed_inputs);
329
                av_free(name);
330
                return AVERROR(ENOMEM);
331
            }
332
24
            match->name    = name;
333
24
            match->pad_idx = pad;
334
        }
335
336
180
        append_inout(&parsed_inputs, &match);
337
338
180
        *buf += strspn(*buf, WHITESPACES);
339
180
        pad++;
340
    }
341
342
11647
    append_inout(&parsed_inputs, curr_inputs);
343
11647
    *curr_inputs = parsed_inputs;
344
345
11647
    return pad;
346
}
347
348
11674
static int parse_outputs(const char **buf, AVFilterInOut **curr_inputs,
349
                         AVFilterInOut **open_inputs,
350
                         AVFilterInOut **open_outputs, void *log_ctx)
351
{
352
11674
    int ret, pad = 0;
353
354
11869
    while (**buf == '[') {
355
195
        char *name = parse_link_name(buf, log_ctx);
356
        AVFilterInOut *match;
357
358
195
        AVFilterInOut *input = *curr_inputs;
359
360
195
        if (!name)
361
            return AVERROR(EINVAL);
362
363
195
        if (!input) {
364
            av_log(log_ctx, AV_LOG_ERROR,
365
                   "No output pad can be associated to link label '%s'.\n", name);
366
            av_free(name);
367
            return AVERROR(EINVAL);
368
        }
369
195
        *curr_inputs = (*curr_inputs)->next;
370
371
        /* First check if the label is not in the open_inputs list */
372
195
        match = extract_inout(name, open_inputs);
373
374
195
        if (match) {
375
            ret = link_filter(input->filter_ctx, input->pad_idx,
376
                              match->filter_ctx, match->pad_idx, log_ctx);
377
            av_freep(&match->name);
378
            av_freep(&name);
379
            av_freep(&match);
380
            av_freep(&input);
381
            if (ret < 0)
382
                return ret;
383
        } else {
384
            /* Not in the list, so add the first input as an open_output */
385
195
            input->name = name;
386
195
            insert_inout(open_outputs, input);
387
        }
388
195
        *buf += strspn(*buf, WHITESPACES);
389
195
        pad++;
390
    }
391
392
11674
    return pad;
393
}
394
395
5935
static int parse_sws_flags(const char **buf, AVFilterGraph *graph)
396
{
397
5935
    char *p = strchr(*buf, ';');
398
399
5935
    if (strncmp(*buf, "sws_flags=", 10))
400
5890
        return 0;
401
402
45
    if (!p) {
403
        av_log(graph, AV_LOG_ERROR, "sws_flags not terminated with ';'.\n");
404
        return AVERROR(EINVAL);
405
    }
406
407
45
    *buf += 4;  // keep the 'flags=' part
408
409
45
    av_freep(&graph->scale_sws_opts);
410
45
    if (!(graph->scale_sws_opts = av_mallocz(p - *buf + 1)))
411
        return AVERROR(ENOMEM);
412
45
    av_strlcpy(graph->scale_sws_opts, *buf, p - *buf + 1);
413
414
45
    *buf = p + 1;
415
45
    return 0;
416
}
417
418
5904
int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
419
                          AVFilterInOut **inputs,
420
                          AVFilterInOut **outputs)
421
{
422
5904
    int index = 0, ret = 0;
423
5904
    char chr = 0;
424
425
5904
    AVFilterInOut *curr_inputs = NULL, *open_inputs = NULL, *open_outputs = NULL;
426
427
5904
    filters += strspn(filters, WHITESPACES);
428
429
5904
    if ((ret = parse_sws_flags(&filters, graph)) < 0)
430
        goto fail;
431
432
    do {
433
        AVFilterContext *filter;
434
11597
        filters += strspn(filters, WHITESPACES);
435
436
11597
        if ((ret = parse_inputs(&filters, &curr_inputs, &open_outputs, graph)) < 0)
437
            goto end;
438
11597
        if ((ret = parse_filter(&filter, &filters, graph, index, graph)) < 0)
439
            goto end;
440
441
442
11597
        if ((ret = link_filter_inouts(filter, &curr_inputs, &open_inputs, graph)) < 0)
443
            goto end;
444
445
11597
        if ((ret = parse_outputs(&filters, &curr_inputs, &open_inputs, &open_outputs,
446
                                 graph)) < 0)
447
            goto end;
448
449
11597
        filters += strspn(filters, WHITESPACES);
450
11597
        chr = *filters++;
451
452

11597
        if (chr == ';' && curr_inputs)
453
            append_inout(&open_outputs, &curr_inputs);
454
11597
        index++;
455

11597
    } while (chr == ',' || chr == ';');
456
457
5904
    if (chr) {
458
        av_log(graph, AV_LOG_ERROR,
459
               "Unable to parse graph description substring: \"%s\"\n",
460
               filters - 1);
461
        ret = AVERROR(EINVAL);
462
        goto end;
463
    }
464
465
5904
    append_inout(&open_outputs, &curr_inputs);
466
467
468
5904
    *inputs  = open_inputs;
469
5904
    *outputs = open_outputs;
470
5904
    return 0;
471
472
 fail:end:
473
    while (graph->nb_filters)
474
        avfilter_free(graph->filters[0]);
475
    av_freep(&graph->filters);
476
    avfilter_inout_free(&open_inputs);
477
    avfilter_inout_free(&open_outputs);
478
    avfilter_inout_free(&curr_inputs);
479
480
    *inputs  = NULL;
481
    *outputs = NULL;
482
483
    return ret;
484
}
485
486
int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
487
                         AVFilterInOut *open_inputs,
488
                         AVFilterInOut *open_outputs, void *log_ctx)
489
{
490
    int ret;
491
    AVFilterInOut *cur, *match, *inputs = NULL, *outputs = NULL;
492
493
    if ((ret = avfilter_graph_parse2(graph, filters, &inputs, &outputs)) < 0)
494
        goto fail;
495
496
    /* First input can be omitted if it is "[in]" */
497
    if (inputs && !inputs->name)
498
        inputs->name = av_strdup("in");
499
    for (cur = inputs; cur; cur = cur->next) {
500
        if (!cur->name) {
501
              av_log(log_ctx, AV_LOG_ERROR,
502
                     "Not enough inputs specified for the \"%s\" filter.\n",
503
                     cur->filter_ctx->filter->name);
504
              ret = AVERROR(EINVAL);
505
              goto fail;
506
        }
507
        if (!(match = extract_inout(cur->name, &open_outputs)))
508
            continue;
509
        ret = avfilter_link(match->filter_ctx, match->pad_idx,
510
                            cur->filter_ctx,   cur->pad_idx);
511
        avfilter_inout_free(&match);
512
        if (ret < 0)
513
            goto fail;
514
    }
515
516
    /* Last output can be omitted if it is "[out]" */
517
    if (outputs && !outputs->name)
518
        outputs->name = av_strdup("out");
519
    for (cur = outputs; cur; cur = cur->next) {
520
        if (!cur->name) {
521
            av_log(log_ctx, AV_LOG_ERROR,
522
                   "Invalid filterchain containing an unlabelled output pad: \"%s\"\n",
523
                   filters);
524
            ret = AVERROR(EINVAL);
525
            goto fail;
526
        }
527
        if (!(match = extract_inout(cur->name, &open_inputs)))
528
            continue;
529
        ret = avfilter_link(cur->filter_ctx,   cur->pad_idx,
530
                            match->filter_ctx, match->pad_idx);
531
        avfilter_inout_free(&match);
532
        if (ret < 0)
533
            goto fail;
534
    }
535
536
 fail:
537
    if (ret < 0) {
538
        while (graph->nb_filters)
539
            avfilter_free(graph->filters[0]);
540
        av_freep(&graph->filters);
541
    }
542
    avfilter_inout_free(&inputs);
543
    avfilter_inout_free(&outputs);
544
    avfilter_inout_free(&open_inputs);
545
    avfilter_inout_free(&open_outputs);
546
    return ret;
547
}
548
549
31
int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters,
550
                         AVFilterInOut **open_inputs_ptr, AVFilterInOut **open_outputs_ptr,
551
                         void *log_ctx)
552
{
553
31
    int index = 0, ret = 0;
554
31
    char chr = 0;
555
556
31
    AVFilterInOut *curr_inputs = NULL;
557
31
    AVFilterInOut *open_inputs  = open_inputs_ptr  ? *open_inputs_ptr  : NULL;
558
31
    AVFilterInOut *open_outputs = open_outputs_ptr ? *open_outputs_ptr : NULL;
559
560
31
    if ((ret = parse_sws_flags(&filters, graph)) < 0)
561
        goto end;
562
563
    do {
564
        AVFilterContext *filter;
565
50
        const char *filterchain = filters;
566
50
        filters += strspn(filters, WHITESPACES);
567
568
50
        if ((ret = parse_inputs(&filters, &curr_inputs, &open_outputs, log_ctx)) < 0)
569
            goto end;
570
571
50
        if ((ret = parse_filter(&filter, &filters, graph, index, log_ctx)) < 0)
572
            goto end;
573
574

50
        if (filter->nb_inputs == 1 && !curr_inputs && !index) {
575
            /* First input pad, assume it is "[in]" if not specified */
576
            const char *tmp = "[in]";
577
            if ((ret = parse_inputs(&tmp, &curr_inputs, &open_outputs, log_ctx)) < 0)
578
                goto end;
579
        }
580
581
50
        if ((ret = link_filter_inouts(filter, &curr_inputs, &open_inputs, log_ctx)) < 0)
582
            goto end;
583
584
50
        if ((ret = parse_outputs(&filters, &curr_inputs, &open_inputs, &open_outputs,
585
                                 log_ctx)) < 0)
586
            goto end;
587
588
50
        filters += strspn(filters, WHITESPACES);
589
50
        chr = *filters++;
590
591

50
        if (chr == ';' && curr_inputs) {
592
            av_log(log_ctx, AV_LOG_ERROR,
593
                   "Invalid filterchain containing an unlabelled output pad: \"%s\"\n",
594
                   filterchain);
595
            ret = AVERROR(EINVAL);
596
            goto end;
597
        }
598
50
        index++;
599

50
    } while (chr == ',' || chr == ';');
600
601
31
    if (chr) {
602
        av_log(log_ctx, AV_LOG_ERROR,
603
               "Unable to parse graph description substring: \"%s\"\n",
604
               filters - 1);
605
        ret = AVERROR(EINVAL);
606
        goto end;
607
    }
608
609
31
    if (curr_inputs) {
610
        /* Last output pad, assume it is "[out]" if not specified */
611
27
        const char *tmp = "[out]";
612
27
        if ((ret = parse_outputs(&tmp, &curr_inputs, &open_inputs, &open_outputs,
613
                                 log_ctx)) < 0)
614
            goto end;
615
    }
616
617
4
end:
618
    /* clear open_in/outputs only if not passed as parameters */
619
31
    if (open_inputs_ptr) *open_inputs_ptr = open_inputs;
620
    else avfilter_inout_free(&open_inputs);
621
31
    if (open_outputs_ptr) *open_outputs_ptr = open_outputs;
622
    else avfilter_inout_free(&open_outputs);
623
31
    avfilter_inout_free(&curr_inputs);
624
625
31
    if (ret < 0) {
626
        while (graph->nb_filters)
627
            avfilter_free(graph->filters[0]);
628
        av_freep(&graph->filters);
629
    }
630
31
    return ret;
631
}