graphparser: fix logic for updating the open_inputs/outputs in avfilter_graph_parse()

Create open_inputs and open_outputs structs if they are not provided by
the user, and free them before exit.

In particular, fix NULL pointer dereference and crash, in case the
passed open_inputs/outputs is NULL and the parsing failed.
This commit is contained in:
Stefano Sabatini 2011-07-01 16:31:16 +02:00
parent c3b6cc61e5
commit df8c675f48

View File

@ -333,38 +333,40 @@ static int parse_outputs(const char **buf, AVFilterInOut **curr_inputs,
}
int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
AVFilterInOut **open_inputs, AVFilterInOut **open_outputs,
AVFilterInOut **open_inputs_ptr, AVFilterInOut **open_outputs_ptr,
void *log_ctx)
{
int index = 0, ret;
int index = 0, ret = 0;
char chr = 0;
AVFilterInOut *curr_inputs = NULL;
AVFilterInOut *open_inputs = open_inputs_ptr ? *open_inputs_ptr : NULL;
AVFilterInOut *open_outputs = open_outputs_ptr ? *open_outputs_ptr : NULL;
do {
AVFilterContext *filter;
const char *filterchain = filters;
filters += strspn(filters, WHITESPACES);
if ((ret = parse_inputs(&filters, &curr_inputs, open_outputs, log_ctx)) < 0)
goto fail;
if ((ret = parse_inputs(&filters, &curr_inputs, &open_outputs, log_ctx)) < 0)
goto end;
if ((ret = parse_filter(&filter, &filters, graph, index, log_ctx)) < 0)
goto fail;
goto end;
if (filter->input_count == 1 && !curr_inputs && !index) {
/* First input can be omitted if it is "[in]" */
const char *tmp = "[in]";
if ((ret = parse_inputs(&tmp, &curr_inputs, open_outputs, log_ctx)) < 0)
goto fail;
if ((ret = parse_inputs(&tmp, &curr_inputs, &open_outputs, log_ctx)) < 0)
goto end;
}
if ((ret = link_filter_inouts(filter, &curr_inputs, open_inputs, log_ctx)) < 0)
goto fail;
if ((ret = link_filter_inouts(filter, &curr_inputs, &open_inputs, log_ctx)) < 0)
goto end;
if ((ret = parse_outputs(&filters, &curr_inputs, open_inputs, open_outputs,
if ((ret = parse_outputs(&filters, &curr_inputs, &open_inputs, &open_outputs,
log_ctx)) < 0)
goto fail;
goto end;
filters += strspn(filters, WHITESPACES);
chr = *filters++;
@ -374,7 +376,7 @@ int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
"Invalid filterchain containing an unlabelled output pad: \"%s\"\n",
filterchain);
ret = AVERROR(EINVAL);
goto fail;
goto end;
}
index++;
} while (chr == ',' || chr == ';');
@ -384,25 +386,29 @@ int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
"Unable to parse graph description substring: \"%s\"\n",
filters - 1);
ret = AVERROR(EINVAL);
goto fail;
goto end;
}
if (open_inputs && *open_inputs && !strcmp((*open_inputs)->name, "out") && curr_inputs) {
if (open_inputs && !strcmp(open_inputs->name, "out") && curr_inputs) {
/* Last output can be omitted if it is "[out]" */
const char *tmp = "[out]";
if ((ret = parse_outputs(&tmp, &curr_inputs, open_inputs, open_outputs,
if ((ret = parse_outputs(&tmp, &curr_inputs, &open_inputs, &open_outputs,
log_ctx)) < 0)
goto fail;
goto end;
}
return 0;
fail:
for (; graph->filter_count > 0; graph->filter_count--)
avfilter_free(graph->filters[graph->filter_count - 1]);
av_freep(&graph->filters);
avfilter_inout_free(open_inputs);
avfilter_inout_free(open_outputs);
end:
/* clear open_in/outputs only if not passed as parameters */
if (open_inputs_ptr) *open_inputs_ptr = open_inputs;
else avfilter_inout_free(&open_inputs);
if (open_outputs_ptr) *open_outputs_ptr = open_outputs;
else avfilter_inout_free(&open_outputs);
avfilter_inout_free(&curr_inputs);
if (ret < 0) {
for (; graph->filter_count > 0; graph->filter_count--)
avfilter_free(graph->filters[graph->filter_count - 1]);
av_freep(&graph->filters);
}
return ret;
}