FFmpeg/libavformat/file.c
Rémi Denis-Courmont add8c46215 Revert "avformat/file: seek back to initial position for fd protocol"
The generally expected behaviour is for software to append from the
current position, not to keep resetting. See also how shell works:
 # (foo && bar) > file
...would normally concatenate the output of both commands to file.

If foo seeks like lavf, bar would instead overwrite the output of
foo (possibly not completely).

This reverts commit 5c3d2177e7.
2024-05-30 18:30:21 +03:00

673 lines
18 KiB
C

/*
* 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 "config_components.h"
#include "libavutil/avstring.h"
#include "libavutil/file_open.h"
#include "libavutil/internal.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"
#include "avio.h"
#if HAVE_DIRENT_H
#include <dirent.h>
#endif
#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
/* Not available in POSIX.1-1996 */
#ifndef S_ISLNK
# ifdef S_IFLNK
# define S_ISLNK(m) (((m) & S_IFLNK) == S_IFLNK)
# else
# define S_ISLNK(m) 0
# endif
#endif
/* Not available in POSIX.1-1996 */
#ifndef S_ISSOCK
# ifdef S_IFSOCK
# define S_ISSOCK(m) (((m) & S_IFMT) == S_IFSOCK)
# else
# define S_ISSOCK(m) 0
# endif
#endif
/* S_ISREG not available on Windows */
#ifndef S_ISREG
# ifdef S_IFREG
# define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
# else
# define S_ISREG(m) 0
# endif
#endif
/* S_ISBLK not available on Windows */
#ifndef S_ISBLK
# ifdef S_IFBLK
# define S_ISBLK(m) (((m) & S_IFMT) == S_IFBLK)
# else
# define S_ISBLK(m) 0
# endif
#endif
/* standard file protocol */
typedef struct FileContext {
const AVClass *class;
int fd;
int trunc;
int blocksize;
int follow;
int seekable;
#if HAVE_DIRENT_H
DIR *dir;
#endif
} FileContext;
static const AVOption file_options[] = {
{ "truncate", "truncate existing files on write", offsetof(FileContext, trunc), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, AV_OPT_FLAG_ENCODING_PARAM },
{ "blocksize", "set I/O operation maximum block size", offsetof(FileContext, blocksize), AV_OPT_TYPE_INT, { .i64 = INT_MAX }, 1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
{ "follow", "Follow a file as it is being written", offsetof(FileContext, follow), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AV_OPT_FLAG_DECODING_PARAM },
{ "seekable", "Sets if the file is seekable", offsetof(FileContext, seekable), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, 0, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_ENCODING_PARAM },
{ NULL }
};
static const AVOption pipe_options[] = {
{ "blocksize", "set I/O operation maximum block size", offsetof(FileContext, blocksize), AV_OPT_TYPE_INT, { .i64 = INT_MAX }, 1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
{ "fd", "set file descriptor", offsetof(FileContext, fd), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, 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 const AVClass pipe_class = {
.class_name = "pipe",
.item_name = av_default_item_name,
.option = pipe_options,
.version = LIBAVUTIL_VERSION_INT,
};
static const AVClass fd_class = {
.class_name = "fd",
.item_name = av_default_item_name,
.option = pipe_options,
.version = LIBAVUTIL_VERSION_INT,
};
static int file_read(URLContext *h, unsigned char *buf, int size)
{
FileContext *c = h->priv_data;
int ret;
size = FFMIN(size, c->blocksize);
ret = read(c->fd, buf, size);
if (ret == 0 && c->follow)
return AVERROR(EAGAIN);
if (ret == 0)
return AVERROR_EOF;
return (ret == -1) ? AVERROR(errno) : ret;
}
static int file_write(URLContext *h, const unsigned char *buf, int size)
{
FileContext *c = h->priv_data;
int ret;
size = FFMIN(size, c->blocksize);
ret = write(c->fd, buf, size);
return (ret == -1) ? AVERROR(errno) : ret;
}
static int file_get_handle(URLContext *h)
{
FileContext *c = h->priv_data;
return c->fd;
}
static int file_check(URLContext *h, int mask)
{
int ret = 0;
const char *filename = h->filename;
av_strstart(filename, "file:", &filename);
{
#if HAVE_ACCESS && defined(R_OK)
if (access(filename, F_OK) < 0)
return AVERROR(errno);
if (mask&AVIO_FLAG_READ)
if (access(filename, R_OK) >= 0)
ret |= AVIO_FLAG_READ;
if (mask&AVIO_FLAG_WRITE)
if (access(filename, W_OK) >= 0)
ret |= AVIO_FLAG_WRITE;
#else
struct stat st;
ret = stat(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;
}
static int fd_dup(URLContext *h, int oldfd)
{
int newfd;
#ifdef F_DUPFD_CLOEXEC
newfd = fcntl(oldfd, F_DUPFD_CLOEXEC, 0);
#else
newfd = dup(oldfd);
#endif
if (newfd == -1)
return newfd;
#if HAVE_FCNTL
if (fcntl(newfd, F_SETFD, FD_CLOEXEC) == -1)
av_log(h, AV_LOG_DEBUG, "Failed to set close on exec\n");
#endif
#if HAVE_SETMODE
setmode(newfd, O_BINARY);
#endif
return newfd;
}
static int file_close(URLContext *h)
{
FileContext *c = h->priv_data;
int ret = close(c->fd);
return (ret == -1) ? AVERROR(errno) : 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;
}
#if CONFIG_FILE_PROTOCOL
static int file_delete(URLContext *h)
{
#if HAVE_UNISTD_H
int ret;
const char *filename = h->filename;
av_strstart(filename, "file:", &filename);
ret = rmdir(filename);
if (ret < 0 && (errno == ENOTDIR
# ifdef _WIN32
|| errno == EINVAL
# endif
))
ret = unlink(filename);
if (ret < 0)
return AVERROR(errno);
return ret;
#else
return AVERROR(ENOSYS);
#endif /* HAVE_UNISTD_H */
}
static int file_move(URLContext *h_src, URLContext *h_dst)
{
const char *filename_src = h_src->filename;
const char *filename_dst = h_dst->filename;
av_strstart(filename_src, "file:", &filename_src);
av_strstart(filename_dst, "file:", &filename_dst);
if (rename(filename_src, filename_dst) < 0)
return AVERROR(errno);
return 0;
}
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 = avpriv_open(filename, access, 0666);
if (fd == -1)
return AVERROR(errno);
c->fd = fd;
h->is_streamed = !fstat(fd, &st) && S_ISFIFO(st.st_mode);
/* Buffer writes more than the default 32k to improve throughput especially
* with networked file systems */
if (!h->is_streamed && flags & AVIO_FLAG_WRITE)
h->min_packet_size = h->max_packet_size = 262144;
if (c->seekable >= 0)
h->is_streamed = !c->seekable;
return 0;
}
static int file_open_dir(URLContext *h)
{
#if HAVE_LSTAT
FileContext *c = h->priv_data;
c->dir = opendir(h->filename);
if (!c->dir)
return AVERROR(errno);
return 0;
#else
return AVERROR(ENOSYS);
#endif /* HAVE_LSTAT */
}
static int file_read_dir(URLContext *h, AVIODirEntry **next)
{
#if HAVE_LSTAT
FileContext *c = h->priv_data;
struct dirent *dir;
char *fullpath = NULL;
*next = ff_alloc_dir_entry();
if (!*next)
return AVERROR(ENOMEM);
do {
errno = 0;
dir = readdir(c->dir);
if (!dir) {
av_freep(next);
return AVERROR(errno);
}
} while (!strcmp(dir->d_name, ".") || !strcmp(dir->d_name, ".."));
fullpath = av_append_path_component(h->filename, dir->d_name);
if (fullpath) {
struct stat st;
if (!lstat(fullpath, &st)) {
if (S_ISDIR(st.st_mode))
(*next)->type = AVIO_ENTRY_DIRECTORY;
else if (S_ISFIFO(st.st_mode))
(*next)->type = AVIO_ENTRY_NAMED_PIPE;
else if (S_ISCHR(st.st_mode))
(*next)->type = AVIO_ENTRY_CHARACTER_DEVICE;
else if (S_ISBLK(st.st_mode))
(*next)->type = AVIO_ENTRY_BLOCK_DEVICE;
else if (S_ISLNK(st.st_mode))
(*next)->type = AVIO_ENTRY_SYMBOLIC_LINK;
else if (S_ISSOCK(st.st_mode))
(*next)->type = AVIO_ENTRY_SOCKET;
else if (S_ISREG(st.st_mode))
(*next)->type = AVIO_ENTRY_FILE;
else
(*next)->type = AVIO_ENTRY_UNKNOWN;
(*next)->group_id = st.st_gid;
(*next)->user_id = st.st_uid;
(*next)->size = st.st_size;
(*next)->filemode = st.st_mode & 0777;
(*next)->modification_timestamp = INT64_C(1000000) * st.st_mtime;
(*next)->access_timestamp = INT64_C(1000000) * st.st_atime;
(*next)->status_change_timestamp = INT64_C(1000000) * st.st_ctime;
}
av_free(fullpath);
}
(*next)->name = av_strdup(dir->d_name);
return 0;
#else
return AVERROR(ENOSYS);
#endif /* HAVE_LSTAT */
}
static int file_close_dir(URLContext *h)
{
#if HAVE_LSTAT
FileContext *c = h->priv_data;
closedir(c->dir);
return 0;
#else
return AVERROR(ENOSYS);
#endif /* HAVE_LSTAT */
}
const 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,
.url_delete = file_delete,
.url_move = file_move,
.priv_data_size = sizeof(FileContext),
.priv_data_class = &file_class,
.url_open_dir = file_open_dir,
.url_read_dir = file_read_dir,
.url_close_dir = file_close_dir,
.default_whitelist = "file,crypto,data"
};
#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;
if (c->fd < 0) {
av_strstart(filename, "pipe:", &filename);
if (!*filename) {
if (flags & AVIO_FLAG_WRITE) {
fd = 1;
} else {
fd = 0;
}
} else {
fd = strtol(filename, &final, 10);
if (*final) /* No digits found, or something like 10ab */
return AVERROR(EINVAL);
}
c->fd = fd;
}
c->fd = fd_dup(h, c->fd);
if (c->fd == -1)
return AVERROR(errno);
h->is_streamed = 1;
return 0;
}
const URLProtocol ff_pipe_protocol = {
.name = "pipe",
.url_open = pipe_open,
.url_read = file_read,
.url_write = file_write,
.url_close = file_close,
.url_get_file_handle = file_get_handle,
.url_check = file_check,
.priv_data_size = sizeof(FileContext),
.priv_data_class = &pipe_class,
.default_whitelist = "crypto,data"
};
#endif /* CONFIG_PIPE_PROTOCOL */
#if CONFIG_FD_PROTOCOL
static int fd_open(URLContext *h, const char *filename, int flags)
{
FileContext *c = h->priv_data;
struct stat st;
if (strcmp(filename, "fd:") != 0) {
av_log(h, AV_LOG_ERROR, "Doesn't support pass file descriptor via URL,"
" please set it via -fd {num}\n");
return AVERROR(EINVAL);
}
if (c->fd < 0) {
if (flags & AVIO_FLAG_WRITE) {
c->fd = 1;
} else {
c->fd = 0;
}
}
if (fstat(c->fd, &st) < 0)
return AVERROR(errno);
h->is_streamed = !(S_ISREG(st.st_mode) || S_ISBLK(st.st_mode));
c->fd = fd_dup(h, c->fd);
if (c->fd == -1)
return AVERROR(errno);
return 0;
}
const URLProtocol ff_fd_protocol = {
.name = "fd",
.url_open = fd_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 = &fd_class,
.default_whitelist = "crypto,data"
};
#endif /* CONFIG_FD_PROTOCOL */
#if CONFIG_ANDROID_CONTENT_PROTOCOL
#include <jni.h>
#include "libavcodec/ffjni.h"
#include "libavcodec/jni.h"
typedef struct JFields {
jclass uri_class;
jmethodID parse_id;
jclass context_class;
jmethodID get_content_resolver_id;
jclass content_resolver_class;
jmethodID open_file_descriptor_id;
jclass parcel_file_descriptor_class;
jmethodID detach_fd_id;
} JFields;
#define OFFSET(x) offsetof(JFields, x)
static const struct FFJniField jfields_mapping[] = {
{ "android/net/Uri", NULL, NULL, FF_JNI_CLASS, OFFSET(uri_class), 1 },
{ "android/net/Uri", "parse", "(Ljava/lang/String;)Landroid/net/Uri;", FF_JNI_STATIC_METHOD, OFFSET(parse_id), 1 },
{ "android/content/Context", NULL, NULL, FF_JNI_CLASS, OFFSET(context_class), 1 },
{ "android/content/Context", "getContentResolver", "()Landroid/content/ContentResolver;", FF_JNI_METHOD, OFFSET(get_content_resolver_id), 1 },
{ "android/content/ContentResolver", NULL, NULL, FF_JNI_CLASS, OFFSET(content_resolver_class), 1 },
{ "android/content/ContentResolver", "openFileDescriptor", "(Landroid/net/Uri;Ljava/lang/String;)Landroid/os/ParcelFileDescriptor;", FF_JNI_METHOD, OFFSET(open_file_descriptor_id), 1 },
{ "android/os/ParcelFileDescriptor", NULL, NULL, FF_JNI_CLASS, OFFSET(parcel_file_descriptor_class), 1 },
{ "android/os/ParcelFileDescriptor", "detachFd", "()I", FF_JNI_METHOD, OFFSET(detach_fd_id), 1 },
{ NULL }
};
#undef OFFSET
static int android_content_open(URLContext *h, const char *filename, int flags)
{
FileContext *c = h->priv_data;
int fd, ret;
struct stat st;
const char *mode_str = "r";
JNIEnv *env;
JFields jfields = { 0 };
jobject application_context = NULL;
jobject url = NULL;
jobject mode = NULL;
jobject uri = NULL;
jobject content_resolver = NULL;
jobject parcel_file_descriptor = NULL;
env = ff_jni_get_env(c);
if (!env) {
return AVERROR(EINVAL);
}
ret = ff_jni_init_jfields(env, &jfields, jfields_mapping, 0, c);
if (ret < 0) {
av_log(c, AV_LOG_ERROR, "failed to initialize jni fields\n");
return ret;
}
application_context = av_jni_get_android_app_ctx();
if (!application_context) {
av_log(c, AV_LOG_ERROR, "application context is not set\n");
ret = AVERROR_EXTERNAL;
goto done;
}
url = ff_jni_utf_chars_to_jstring(env, filename, c);
if (!url) {
ret = AVERROR_EXTERNAL;
goto done;
}
if (flags & AVIO_FLAG_WRITE && flags & AVIO_FLAG_READ)
mode_str = "rw";
else if (flags & AVIO_FLAG_WRITE)
mode_str = "w";
mode = ff_jni_utf_chars_to_jstring(env, mode_str, c);
if (!mode) {
ret = AVERROR_EXTERNAL;
goto done;
}
uri = (*env)->CallStaticObjectMethod(env, jfields.uri_class, jfields.parse_id, url);
ret = ff_jni_exception_check(env, 1, c);
if (ret < 0)
goto done;
content_resolver = (*env)->CallObjectMethod(env, application_context, jfields.get_content_resolver_id);
ret = ff_jni_exception_check(env, 1, c);
if (ret < 0)
goto done;
parcel_file_descriptor = (*env)->CallObjectMethod(env, content_resolver, jfields.open_file_descriptor_id, uri, mode);
ret = ff_jni_exception_check(env, 1, c);
if (ret < 0)
goto done;
fd = (*env)->CallIntMethod(env, parcel_file_descriptor, jfields.detach_fd_id);
ret = ff_jni_exception_check(env, 1, c);
if (ret < 0)
goto done;
if (fstat(fd, &st) < 0) {
close(fd);
return AVERROR(errno);
}
c->fd = fd;
h->is_streamed = !(S_ISREG(st.st_mode) || S_ISBLK(st.st_mode));
done:
(*env)->DeleteLocalRef(env, url);
(*env)->DeleteLocalRef(env, mode);
(*env)->DeleteLocalRef(env, uri);
(*env)->DeleteLocalRef(env, content_resolver);
(*env)->DeleteLocalRef(env, parcel_file_descriptor);
ff_jni_reset_jfields(env, &jfields, jfields_mapping, 0, c);
return ret;
}
static const AVOption android_content_options[] = {
{ "blocksize", "set I/O operation maximum block size", offsetof(FileContext, blocksize), AV_OPT_TYPE_INT, { .i64 = INT_MAX }, 1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
{ NULL }
};
static const AVClass android_content_class = {
.class_name = "android_content",
.item_name = av_default_item_name,
.option = android_content_options,
.version = LIBAVUTIL_VERSION_INT,
};
const URLProtocol ff_android_content_protocol = {
.name = "content",
.url_open = android_content_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 = NULL,
.priv_data_size = sizeof(FileContext),
.priv_data_class = &android_content_class,
};
#endif /* CONFIG_ANDROID_CONTENT_PROTOCOL */