From b750101eb236130cf056c675997decbac904cc49 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:35:18 +0200 Subject: Adding upstream version 252.22. Signed-off-by: Daniel Baumann --- src/basic/sync-util.c | 163 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 163 insertions(+) create mode 100644 src/basic/sync-util.c (limited to 'src/basic/sync-util.c') diff --git a/src/basic/sync-util.c b/src/basic/sync-util.c new file mode 100644 index 0000000..e2d4a3d --- /dev/null +++ b/src/basic/sync-util.c @@ -0,0 +1,163 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include +#include + +#include "fd-util.h" +#include "fs-util.h" +#include "path-util.h" +#include "sync-util.h" + +int fsync_directory_of_file(int fd) { + _cleanup_close_ int dfd = -1; + struct stat st; + int r; + + assert(fd >= 0); + + /* We only reasonably can do this for regular files and directories, or for O_PATH fds, hence check + * for the inode type first */ + if (fstat(fd, &st) < 0) + return -errno; + + if (S_ISDIR(st.st_mode)) { + dfd = openat(fd, "..", O_RDONLY|O_DIRECTORY|O_CLOEXEC, 0); + if (dfd < 0) + return -errno; + + } else if (!S_ISREG(st.st_mode)) { /* Regular files are OK regardless if O_PATH or not, for all other + * types check O_PATH flag */ + int flags; + + flags = fcntl(fd, F_GETFL); + if (flags < 0) + return -errno; + + if (!FLAGS_SET(flags, O_PATH)) /* If O_PATH this refers to the inode in the fs, in which case + * we can sensibly do what is requested. Otherwise this refers + * to a socket, fifo or device node, where the concept of a + * containing directory doesn't make too much sense. */ + return -ENOTTY; + } + + if (dfd < 0) { + _cleanup_free_ char *path = NULL; + + r = fd_get_path(fd, &path); + if (r < 0) { + log_debug_errno(r, "Failed to query /proc/self/fd/%d%s: %m", + fd, + r == -ENOSYS ? ", ignoring" : ""); + + if (r == -ENOSYS) + /* If /proc is not available, we're most likely running in some + * chroot environment, and syncing the directory is not very + * important in that case. Let's just silently do nothing. */ + return 0; + + return r; + } + + if (!path_is_absolute(path)) + return -EINVAL; + + dfd = open_parent(path, O_CLOEXEC|O_NOFOLLOW, 0); + if (dfd < 0) + return dfd; + } + + return RET_NERRNO(fsync(dfd)); +} + +int fsync_full(int fd) { + int r, q; + + /* Sync both the file and the directory */ + + r = RET_NERRNO(fsync(fd)); + + q = fsync_directory_of_file(fd); + if (r < 0) /* Return earlier error */ + return r; + if (q == -ENOTTY) /* Ignore if the 'fd' refers to a block device or so which doesn't really have a + * parent dir */ + return 0; + return q; +} + +int fsync_path_at(int at_fd, const char *path) { + _cleanup_close_ int opened_fd = -1; + int fd; + + if (isempty(path)) { + if (at_fd == AT_FDCWD) { + opened_fd = open(".", O_RDONLY|O_DIRECTORY|O_CLOEXEC); + if (opened_fd < 0) + return -errno; + + fd = opened_fd; + } else + fd = at_fd; + } else { + opened_fd = openat(at_fd, path, O_RDONLY|O_CLOEXEC|O_NONBLOCK); + if (opened_fd < 0) + return -errno; + + fd = opened_fd; + } + + return RET_NERRNO(fsync(fd)); +} + +int fsync_parent_at(int at_fd, const char *path) { + _cleanup_close_ int opened_fd = -1; + + if (isempty(path)) { + if (at_fd != AT_FDCWD) + return fsync_directory_of_file(at_fd); + + opened_fd = open("..", O_RDONLY|O_DIRECTORY|O_CLOEXEC); + if (opened_fd < 0) + return -errno; + + return RET_NERRNO(fsync(opened_fd)); + } + + opened_fd = openat(at_fd, path, O_PATH|O_CLOEXEC|O_NOFOLLOW); + if (opened_fd < 0) + return -errno; + + return fsync_directory_of_file(opened_fd); +} + +int fsync_path_and_parent_at(int at_fd, const char *path) { + _cleanup_close_ int opened_fd = -1; + + if (isempty(path)) { + if (at_fd != AT_FDCWD) + return fsync_full(at_fd); + + opened_fd = open(".", O_RDONLY|O_DIRECTORY|O_CLOEXEC); + } else + opened_fd = openat(at_fd, path, O_RDONLY|O_NOFOLLOW|O_NONBLOCK|O_CLOEXEC); + if (opened_fd < 0) + return -errno; + + return fsync_full(opened_fd); +} + +int syncfs_path(int at_fd, const char *path) { + _cleanup_close_ int fd = -1; + + if (isempty(path)) { + if (at_fd != AT_FDCWD) + return RET_NERRNO(syncfs(at_fd)); + + fd = open(".", O_RDONLY|O_DIRECTORY|O_CLOEXEC); + } else + fd = openat(at_fd, path, O_RDONLY|O_CLOEXEC|O_NONBLOCK); + if (fd < 0) + return -errno; + + return RET_NERRNO(syncfs(fd)); +} -- cgit v1.2.3