1 /*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19 #include "config.h"
20 #include "file.h"
21 #include "internal.h"
22 #include "log.h"
23 #include "mem.h"
24 #include <fcntl.h>
25 #include <sys/stat.h>
26 #if HAVE_UNISTD_H
27 #include <unistd.h>
28 #endif
29 #if HAVE_IO_H
30 #include <io.h>
31 #endif
32 #if HAVE_MMAP
33 #include <sys/mman.h>
34 #elif HAVE_MAPVIEWOFFILE
35 #include <windows.h>
36 #endif
37
38 typedef struct FileLogContext {
39 const AVClass *class;
40 int log_offset;
41 void *log_ctx;
42 } FileLogContext;
43
44 static const AVClass file_log_ctx_class = {
45 .class_name = "FILE",
46 .item_name = av_default_item_name,
47 .option = NULL,
48 .version = LIBAVUTIL_VERSION_INT,
49 .log_level_offset_offset = offsetof(FileLogContext, log_offset),
50 .parent_log_context_offset = offsetof(FileLogContext, log_ctx),
51 };
52
av_file_map(const char * filename,uint8_t ** bufptr,size_t * size,int log_offset,void * log_ctx)53 int av_file_map(const char *filename, uint8_t **bufptr, size_t *size,
54 int log_offset, void *log_ctx)
55 {
56 FileLogContext file_log_ctx = { &file_log_ctx_class, log_offset, log_ctx };
57 int err, fd = avpriv_open(filename, O_RDONLY);
58 struct stat st;
59 av_unused void *ptr;
60 off_t off_size;
61 char errbuf[128];
62 *bufptr = NULL;
63 *size = 0;
64
65 if (fd < 0) {
66 err = AVERROR(errno);
67 av_strerror(err, errbuf, sizeof(errbuf));
68 av_log(&file_log_ctx, AV_LOG_ERROR, "Cannot read file '%s': %s\n", filename, errbuf);
69 return err;
70 }
71
72 if (fstat(fd, &st) < 0) {
73 err = AVERROR(errno);
74 av_strerror(err, errbuf, sizeof(errbuf));
75 av_log(&file_log_ctx, AV_LOG_ERROR, "Error occurred in fstat(): %s\n", errbuf);
76 close(fd);
77 return err;
78 }
79
80 off_size = st.st_size;
81 if (off_size > SIZE_MAX) {
82 av_log(&file_log_ctx, AV_LOG_ERROR,
83 "File size for file '%s' is too big\n", filename);
84 close(fd);
85 return AVERROR(EINVAL);
86 }
87 *size = off_size;
88
89 if (!*size) {
90 *bufptr = NULL;
91 goto out;
92 }
93
94 #if HAVE_MMAP
95 ptr = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
96 if (ptr == MAP_FAILED) {
97 err = AVERROR(errno);
98 av_strerror(err, errbuf, sizeof(errbuf));
99 av_log(&file_log_ctx, AV_LOG_ERROR, "Error occurred in mmap(): %s\n", errbuf);
100 close(fd);
101 *size = 0;
102 return err;
103 }
104 *bufptr = ptr;
105 #elif HAVE_MAPVIEWOFFILE
106 {
107 HANDLE mh, fh = (HANDLE)_get_osfhandle(fd);
108
109 mh = CreateFileMapping(fh, NULL, PAGE_READONLY, 0, 0, NULL);
110 if (!mh) {
111 av_log(&file_log_ctx, AV_LOG_ERROR, "Error occurred in CreateFileMapping()\n");
112 close(fd);
113 *size = 0;
114 return -1;
115 }
116
117 ptr = MapViewOfFile(mh, FILE_MAP_READ, 0, 0, *size);
118 CloseHandle(mh);
119 if (!ptr) {
120 av_log(&file_log_ctx, AV_LOG_ERROR, "Error occurred in MapViewOfFile()\n");
121 close(fd);
122 *size = 0;
123 return -1;
124 }
125
126 *bufptr = ptr;
127 }
128 #else
129 *bufptr = av_malloc(*size);
130 if (!*bufptr) {
131 av_log(&file_log_ctx, AV_LOG_ERROR, "Memory allocation error occurred\n");
132 close(fd);
133 *size = 0;
134 return AVERROR(ENOMEM);
135 }
136 read(fd, *bufptr, *size);
137 #endif
138
139 out:
140 close(fd);
141 return 0;
142 }
143
av_file_unmap(uint8_t * bufptr,size_t size)144 void av_file_unmap(uint8_t *bufptr, size_t size)
145 {
146 if (!size || !bufptr)
147 return;
148 #if HAVE_MMAP
149 munmap(bufptr, size);
150 #elif HAVE_MAPVIEWOFFILE
151 UnmapViewOfFile(bufptr);
152 #else
153 av_free(bufptr);
154 #endif
155 }
156
av_tempfile(const char * prefix,char ** filename,int log_offset,void * log_ctx)157 int av_tempfile(const char *prefix, char **filename, int log_offset, void *log_ctx) {
158 return avpriv_tempfile(prefix, filename, log_offset, log_ctx);
159 }
160