libavformat/file.c

   1 /*
   2  * Buffered file io for ffmpeg system
   3  * Copyright (c) 2001 Fabrice Bellard
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "libavutil/avstring.h"
  23 #include "avformat.h"
  24 #include <fcntl.h>
  25 #if HAVE_SETMODE
  26 #include <io.h>
  27 #endif
  28 #include <unistd.h>
  29 #include <sys/stat.h>
  30 #include <stdlib.h>
  31 #include "os_support.h"
  32
  33
  34 /* standard file protocol */
  35
  36 static int file_read(URLContext *h, unsigned char *buf, int size)
  37 {
  38     int fd = (intptr_t) h->priv_data;
  39     return read(fd, buf, size);
  40 }
  41
  42 static int file_write(URLContext *h, const unsigned char *buf, int size)
  43 {
  44     int fd = (intptr_t) h->priv_data;
  45     return write(fd, buf, size);
  46 }
  47
  48 static int file_get_handle(URLContext *h)
  49 {
  50     return (intptr_t) h->priv_data;
  51 }
  52
  53 #if CONFIG_FILE_PROTOCOL
  54
  55 static int file_open(URLContext *h, const char *filename, int flags)
  56 {
  57     int access;
  58     int fd;
  59
  60     av_strstart(filename, "file:", &filename);
  61
  62     if (flags & URL_RDWR) {
  63         access = O_CREAT | O_TRUNC | O_RDWR;
  64     } else if (flags & URL_WRONLY) {
  65         access = O_CREAT | O_TRUNC | O_WRONLY;
  66     } else {
  67         access = O_RDONLY;
  68     }
  69 #ifdef O_BINARY
  70     access |= O_BINARY;
  71 #endif
  72     fd = open(filename, access, 0666);
  73     if (fd == -1)
  74         return AVERROR(errno);
  75     h->priv_data = (void *) (intptr_t) fd;
  76     return 0;
  77 }
  78
  79 /* XXX: use llseek */
  80 static int64_t file_seek(URLContext *h, int64_t pos, int whence)
  81 {
  82     int fd = (intptr_t) h->priv_data;
  83     if (whence == AVSEEK_SIZE) {
  84         struct stat st;
  85         int ret = fstat(fd, &st);
  86         return ret < 0 ? AVERROR(errno) : st.st_size;
  87     }
  88     return lseek(fd, pos, whence);
  89 }
  90
  91 static int file_close(URLContext *h)
  92 {
  93     int fd = (intptr_t) h->priv_data;
  94     return close(fd);
  95 }
  96
  97 URLProtocol file_protocol = {
  98     "file",
  99     file_open,
 100     file_read,
 101     file_write,
 102     file_seek,
 103     file_close,
 104     .url_get_file_handle = file_get_handle,
 105 };
 106
 107 #endif /* CONFIG_FILE_PROTOCOL */
 108
 109 #if CONFIG_PIPE_PROTOCOL
 110
 111 static int pipe_open(URLContext *h, const char *filename, int flags)
 112 {
 113     int fd;
 114     char *final;
 115     av_strstart(filename, "pipe:", &filename);
 116
 117     fd = strtol(filename, &final, 10);
 118     if((filename == final) || *final ) {/* No digits found, or something like 10ab */
 119         if (flags & URL_WRONLY) {
 120             fd = 1;
 121         } else {
 122             fd = 0;
 123         }
 124     }
 125 #if HAVE_SETMODE
 126     setmode(fd, O_BINARY);
 127 #endif
 128     h->priv_data = (void *) (intptr_t) fd;
 129     h->is_streamed = 1;
 130     return 0;
 131 }
 132
 133 URLProtocol pipe_protocol = {
 134     "pipe",
 135     pipe_open,
 136     file_read,
 137     file_write,
 138     .url_get_file_handle = file_get_handle,
 139 };
 140
 141 #endif /* CONFIG_PIPE_PROTOCOL */