/* * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "config.h"#include "avutil.h"#include "avassert.h" /** * @file * various utility functions */ const char *av_get_media_type_string(enum AVMediaType media_type){    switch (media_type) {    case AVMEDIA_TYPE_VIDEO:      return "video";    case AVMEDIA_TYPE_AUDIO:      return "audio";    case AVMEDIA_TYPE_DATA:       return "data";    case AVMEDIA_TYPE_SUBTITLE:   return "subtitle";    case AVMEDIA_TYPE_ATTACHMENT: return "attachment";    default:                      return NULL;    }} char av_get_picture_type_char(enum AVPictureType pict_type){    switch (pict_type) {    case AV_PICTURE_TYPE_I:  return 'I';    case AV_PICTURE_TYPE_P:  return 'P';    case AV_PICTURE_TYPE_B:  return 'B';    case AV_PICTURE_TYPE_S:  return 'S';    case AV_PICTURE_TYPE_SI: return 'i';    case AV_PICTURE_TYPE_SP: return 'p';    case AV_PICTURE_TYPE_BI: return 'b';    default:                 return '?';    }} #if FF_API_OPT_INT_LISTunsigned av_int_list_length_for_size(unsigned elsize,                                     const void *list, uint64_t term){    unsigned i;     if (!list)        return 0;#define LIST_LENGTH(type) \    { type t = term, *l = (type *)list; for (i = 0; l[i] != t; i++); }    switch (elsize) {    case 1: LIST_LENGTH(uint8_t);  break;    case 2: LIST_LENGTH(uint16_t); break;    case 4: LIST_LENGTH(uint32_t); break;    case 8: LIST_LENGTH(uint64_t); break;    default: av_assert0(!"valid element size");    }    return i;}#endif char *av_fourcc_make_string(char *buf, uint32_t fourcc){    int i;    char *orig_buf = buf;    size_t buf_size = AV_FOURCC_MAX_STRING_SIZE;     for (i = 0; i < 4; i++) {        const int c = fourcc & 0xff;        const int print_chr = (c >= '0' && c <= '9') ||                              (c >= 'a' && c <= 'z') ||                              (c >= 'A' && c <= 'Z') ||                              (c && strchr(". -_", c));        const int len = snprintf(buf, buf_size, print_chr ? "%c" : "[%d]", c);        if (len < 0)            break;        buf += len;        buf_size = buf_size > len ? buf_size - len : 0;        fourcc >>= 8;    }     return orig_buf;} AVRational av_get_time_base_q(void){    return (AVRational){1, AV_TIME_BASE};} void av_assert0_fpu(void) {#if HAVE_MMX_INLINE    uint16_t state[14];     __asm__ volatile (        "fstenv %0 \n\t"        : "+m" (state)        :        : "memory"    );    av_assert0((state[4] & 3) == 3);#endif}