summaryrefslogtreecommitdiffstats
path: root/libavformat/file.c
blob: e09a64b37cfd0597c4eab8ad81a538c47ac13020 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
/*
 * buffered file I/O
 * Copyright (c) 2001 Fabrice Bellard
 *
 * 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 "libavutil/avstring.h"
#include "libavutil/opt.h"
#include "avformat.h"
#include <fcntl.h>
#if HAVE_IO_H
#include <io.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/stat.h>
#include <stdlib.h>
#include "os_support.h"
#include "url.h"

/* Some systems may not have S_ISFIFO */
#ifndef S_ISFIFO
#  ifdef S_IFIFO
#    define S_ISFIFO(m) (((m) & S_IFMT) == S_IFIFO)
#  else
#    define S_ISFIFO(m) 0
#  endif
#endif

/* standard file protocol */

typedef struct FileContext {
    const AVClass *class;
    int fd;
    int trunc;
} FileContext;

static const AVOption file_options[] = {
    { "truncate", "Truncate existing files on write", offsetof(FileContext, trunc), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, AV_OPT_FLAG_ENCODING_PARAM },
    { NULL }
};

static const AVClass file_class = {
    .class_name = "file",
    .item_name  = av_default_item_name,
    .option     = file_options,
    .version    = LIBAVUTIL_VERSION_INT,
};

static int file_read(URLContext *h, unsigned char *buf, int size)
{
    FileContext *c = h->priv_data;
    int r = read(c->fd, buf, size);
    return (-1 == r)?AVERROR(errno):r;
}

static int file_write(URLContext *h, const unsigned char *buf, int size)
{
    FileContext *c = h->priv_data;
    int r = write(c->fd, buf, size);
    return (-1 == r)?AVERROR(errno):r;
}

static int file_get_handle(URLContext *h)
{
    FileContext *c = h->priv_data;
    return c->fd;
}

static int file_check(URLContext *h, int mask)
{
#if HAVE_ACCESS && defined(R_OK)
    int ret = 0;
    if (access(h->filename, F_OK) < 0)
        return AVERROR(errno);
    if (mask&AVIO_FLAG_READ)
        if (access(h->filename, R_OK) >= 0)
            ret |= AVIO_FLAG_READ;
    if (mask&AVIO_FLAG_WRITE)
        if (access(h->filename, W_OK) >= 0)
            ret |= AVIO_FLAG_WRITE;
#else
    struct stat st;
    int ret = stat(h->filename, &st);
    if (ret < 0)
        return AVERROR(errno);

    ret |= st.st_mode&S_IRUSR ? mask&AVIO_FLAG_READ  : 0;
    ret |= st.st_mode&S_IWUSR ? mask&AVIO_FLAG_WRITE : 0;
#endif
    return ret;
}

#if CONFIG_FILE_PROTOCOL

static int file_open(URLContext *h, const char *filename, int flags)
{
    FileContext *c = h->priv_data;
    int access;
    int fd;
    struct stat st;

    av_strstart(filename, "file:", &filename);

    if (flags & AVIO_FLAG_WRITE && flags & AVIO_FLAG_READ) {
        access = O_CREAT | O_RDWR;
        if (c->trunc)
            access |= O_TRUNC;
    } else if (flags & AVIO_FLAG_WRITE) {
        access = O_CREAT | O_WRONLY;
        if (c->trunc)
            access |= O_TRUNC;
    } else {
        access = O_RDONLY;
    }
#ifdef O_BINARY
    access |= O_BINARY;
#endif
    fd = open(filename, access, 0666);
    if (fd == -1)
        return AVERROR(errno);
    c->fd = fd;

    h->is_streamed = !fstat(fd, &st) && S_ISFIFO(st.st_mode);

    return 0;
}

/* XXX: use llseek */
static int64_t file_seek(URLContext *h, int64_t pos, int whence)
{
    FileContext *c = h->priv_data;
    int64_t ret;

    if (whence == AVSEEK_SIZE) {
        struct stat st;
        ret = fstat(c->fd, &st);
        return ret < 0 ? AVERROR(errno) : (S_ISFIFO(st.st_mode) ? 0 : st.st_size);
    }

    ret = lseek(c->fd, pos, whence);

    return ret < 0 ? AVERROR(errno) : ret;
}

static int file_close(URLContext *h)
{
    FileContext *c = h->priv_data;
    return close(c->fd);
}

URLProtocol ff_file_protocol = {
    .name                = "file",
    .url_open            = file_open,
    .url_read            = file_read,
    .url_write           = file_write,
    .url_seek            = file_seek,
    .url_close           = file_close,
    .url_get_file_handle = file_get_handle,
    .url_check           = file_check,
    .priv_data_size      = sizeof(FileContext),
    .priv_data_class     = &file_class,
};

#endif /* CONFIG_FILE_PROTOCOL */

#if CONFIG_PIPE_PROTOCOL

static int pipe_open(URLContext *h, const char *filename, int flags)
{
    FileContext *c = h->priv_data;
    int fd;
    char *final;
    av_strstart(filename, "pipe:", &filename);

    fd = strtol(filename, &final, 10);
    if((filename == final) || *final ) {/* No digits found, or something like 10ab */
        if (flags & AVIO_FLAG_WRITE) {
            fd = 1;
        } else {
            fd = 0;
        }
    }
#if HAVE_SETMODE
    setmode(fd, O_BINARY);
#endif
    c->fd = fd;
    h->is_streamed = 1;
    return 0;
}

URLProtocol ff_pipe_protocol = {
    .name                = "pipe",
    .url_open            = pipe_open,
    .url_read            = file_read,
    .url_write           = file_write,
    .url_get_file_handle = file_get_handle,
    .url_check           = file_check,
    .priv_data_size      = sizeof(FileContext),
};

#endif /* CONFIG_PIPE_PROTOCOL */
OpenPOWER on IntegriCloud