static char* mpjpeg_get_boundary(AVIOContext* pb) { uint8_t *mime_type = NULL; const char *start; const char *end; uint8_t *res = NULL; int len; /* get MIME type, and skip to the first parameter */ av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type); start = mime_type; while (start != NULL && *start != '\0') { start = strchr(start, ';'); if (start) start = start+1; while (av_isspace(*start)) start++; if (!av_stristart(start, "boundary=", &start)) { end = strchr(start, ';'); if (end) len = end - start - 1; else len = strlen(start); res = av_strndup(start, len); break; } } av_freep(&mime_type); return res; }