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 <dirent.h>
  25 #include <fcntl.h>
  26 #if HAVE_SETMODE
  27 #include <io.h>
  28 #endif
  29 #include <unistd.h>
  30 #include <sys/time.h>
  31 #include <stdlib.h>
  32 #include "os_support.h"
  33
  34
  35 /* standard file protocol */
  36
  37 static int file_opendir(URLContext *h, const char *path, int flags)
  38 {
  39     DIR *dir;
  40
  41     if(!(dir = opendir(path)))
  42         return -1;
  43     h->priv_data = dir;
  44     return 0;
  45 }
  46
  47 static int file_readdir(URLContext *h, char *filename, int size)
  48 {
  49     DIR *dir = h->priv_data;
  50     struct dirent *file = readdir(dir);
  51
  52     if(!file)
  53         return -1;
  54     if(strlen(h->filename)+strlen(file->d_name) + 2 > size)
  55         return -1;
  56     strcpy(filename, h->filename);
  57     av_strlcat(filename, "/", size);
  58     av_strlcat(filename, file->d_name, size);
  59     return 0;
  60 }
  61
  62 static int file_closedir(URLContext *h)
  63 {
  64     DIR *dir = h->priv_data;
  65     closedir(dir);
  66     return 0;
  67 }
  68
  69 static int file_open(URLContext *h, const char *filename, int flags)
  70 {
  71     int access;
  72     int fd;
  73
  74     av_strstart(filename, "file:", &filename);
  75
  76     if (flags & URL_DIR)
  77         return file_opendir(h, filename, flags);
  78     if (flags & URL_RDWR) {
  79         access = O_CREAT | O_TRUNC | O_RDWR;
  80     } else if (flags & URL_WRONLY) {
  81         access = O_CREAT | O_TRUNC | O_WRONLY;
  82     } else {
  83         access = O_RDONLY;
  84     }
  85 #ifdef O_BINARY
  86     access |= O_BINARY;
  87 #endif
  88     fd = open(filename, access, 0666);
  89     if (fd < 0)
  90         return AVERROR(ENOENT);
  91     h->priv_data = (void *)(size_t)fd;
  92     return 0;
  93 }
  94
  95 static int file_read(URLContext *h, unsigned char *buf, int size)
  96 {
  97     int fd = (size_t)h->priv_data;
  98     if(h->flags&URL_DIR)
  99         return file_readdir(h, buf, size);
 100     return read(fd, buf, size);
 101 }
 102
 103 static int file_write(URLContext *h, unsigned char *buf, int size)
 104 {
 105     int fd = (size_t)h->priv_data;
 106     if(h->flags&URL_DIR)
 107         return AVERROR(EIO);
 108     return write(fd, buf, size);
 109 }
 110
 111 /* XXX: use llseek */
 112 static int64_t file_seek(URLContext *h, int64_t pos, int whence)
 113 {
 114     int fd = (size_t)h->priv_data;
 115     if(h->flags&URL_DIR)
 116         return AVERROR(EPIPE);
 117     return lseek(fd, pos, whence);
 118 }
 119
 120 static int file_close(URLContext *h)
 121 {
 122     int fd = (size_t)h->priv_data;
 123     if(h->flags&URL_DIR)
 124         return file_closedir(h);
 125     return close(fd);
 126 }
 127
 128 URLProtocol file_protocol = {
 129     "file",
 130     file_open,
 131     file_read,
 132     file_write,
 133     file_seek,
 134     file_close,
 135 };
 136
 137 /* pipe protocol */
 138
 139 static int pipe_open(URLContext *h, const char *filename, int flags)
 140 {
 141     int fd;
 142     char *final;
 143     av_strstart(filename, "pipe:", &filename);
 144
 145     fd = strtol(filename, &final, 10);
 146     if((filename == final) || *final ) {/* No digits found, or something like 10ab */
 147         if (flags & URL_WRONLY) {
 148             fd = 1;
 149         } else {
 150             fd = 0;
 151         }
 152     }
 153 #if HAVE_SETMODE
 154     setmode(fd, O_BINARY);
 155 #endif
 156     h->priv_data = (void *)(size_t)fd;
 157     h->is_streamed = 1;
 158     return 0;
 159 }
 160
 161 URLProtocol pipe_protocol = {
 162     "pipe",
 163     pipe_open,
 164     file_read,
 165     file_write,
 166 };