1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2014 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 #include <sys/sendfile.h>
23 #include <sys/xattr.h>
25 //#include "alloc-util.h"
26 //#include "btrfs-util.h"
27 //#include "chattr-util.h"
29 //#include "dirent-util.h"
30 //#include "fd-util.h"
32 //#include "fs-util.h"
34 //#include "string-util.h"
36 //#include "umask-util.h"
38 //#include "xattr-util.h"
40 #define COPY_BUFFER_SIZE (16*1024)
42 int copy_bytes(int fdf, int fdt, uint64_t max_bytes, bool try_reflink) {
43 bool try_sendfile = true, try_splice = true;
48 /// UNNEEDED by elogind
50 /* Try btrfs reflinks first. */
52 max_bytes == (uint64_t) -1 &&
53 lseek(fdf, 0, SEEK_CUR) == 0 &&
54 lseek(fdt, 0, SEEK_CUR) == 0) {
56 r = btrfs_reflink(fdf, fdt);
58 return 0; /* we copied the whole thing, hence hit EOF, return 0 */
62 size_t m = COPY_BUFFER_SIZE;
65 if (max_bytes != (uint64_t) -1) {
70 if ((uint64_t) m > max_bytes)
71 m = (size_t) max_bytes;
74 /* First try sendfile(), unless we already tried */
77 n = sendfile(fdt, fdf, NULL, m);
79 if (errno != EINVAL && errno != ENOSYS)
83 /* use fallback below */
84 } else if (n == 0) /* EOF */
91 /* The try splice, unless we already tried */
93 n = splice(fdf, NULL, fdt, NULL, m, 0);
95 if (errno != EINVAL && errno != ENOSYS)
99 /* use fallback below */
100 } else if (n == 0) /* EOF */
107 /* As a fallback just copy bits by hand */
111 n = read(fdf, buf, m);
114 if (n == 0) /* EOF */
117 r = loop_write(fdt, buf, (size_t) n, false);
123 if (max_bytes != (uint64_t) -1) {
124 assert(max_bytes >= (uint64_t) n);
129 return 0; /* return 0 if we hit EOF earlier than the size limit */
132 /// UNNEEDED by elogind
134 static int fd_copy_symlink(int df, const char *from, const struct stat *st, int dt, const char *to) {
135 _cleanup_free_ char *target = NULL;
142 r = readlinkat_malloc(df, from, &target);
146 if (symlinkat(target, dt, to) < 0)
149 if (fchownat(dt, to, st->st_uid, st->st_gid, AT_SYMLINK_NOFOLLOW) < 0)
155 static int fd_copy_regular(int df, const char *from, const struct stat *st, int dt, const char *to) {
156 _cleanup_close_ int fdf = -1, fdt = -1;
157 struct timespec ts[2];
164 fdf = openat(df, from, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
168 fdt = openat(dt, to, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, st->st_mode & 07777);
172 r = copy_bytes(fdf, fdt, (uint64_t) -1, true);
178 if (fchown(fdt, st->st_uid, st->st_gid) < 0)
181 if (fchmod(fdt, st->st_mode & 07777) < 0)
186 (void) futimens(fdt, ts);
188 (void) copy_xattr(fdf, fdt);
201 static int fd_copy_fifo(int df, const char *from, const struct stat *st, int dt, const char *to) {
208 r = mkfifoat(dt, to, st->st_mode & 07777);
212 if (fchownat(dt, to, st->st_uid, st->st_gid, AT_SYMLINK_NOFOLLOW) < 0)
215 if (fchmodat(dt, to, st->st_mode & 07777, 0) < 0)
221 static int fd_copy_node(int df, const char *from, const struct stat *st, int dt, const char *to) {
228 r = mknodat(dt, to, st->st_mode, st->st_rdev);
232 if (fchownat(dt, to, st->st_uid, st->st_gid, AT_SYMLINK_NOFOLLOW) < 0)
235 if (fchmodat(dt, to, st->st_mode & 07777, 0) < 0)
241 static int fd_copy_directory(
244 const struct stat *st,
247 dev_t original_device,
250 _cleanup_close_ int fdf = -1, fdt = -1;
251 _cleanup_closedir_ DIR *d = NULL;
260 fdf = openat(df, from, O_RDONLY|O_DIRECTORY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
262 fdf = fcntl(df, F_DUPFD_CLOEXEC, 3);
269 r = mkdirat(dt, to, st->st_mode & 07777);
272 else if (errno == EEXIST && merge)
277 fdt = openat(dt, to, O_RDONLY|O_DIRECTORY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
284 struct timespec ut[2] = {
289 if (fchown(fdt, st->st_uid, st->st_gid) < 0)
292 if (fchmod(fdt, st->st_mode & 07777) < 0)
295 (void) futimens(fdt, ut);
296 (void) copy_xattr(dirfd(d), fdt);
299 FOREACH_DIRENT_ALL(de, d, return -errno) {
303 if (STR_IN_SET(de->d_name, ".", ".."))
306 if (fstatat(dirfd(d), de->d_name, &buf, AT_SYMLINK_NOFOLLOW) < 0) {
311 if (buf.st_dev != original_device)
314 if (S_ISREG(buf.st_mode))
315 q = fd_copy_regular(dirfd(d), de->d_name, &buf, fdt, de->d_name);
316 else if (S_ISDIR(buf.st_mode))
317 q = fd_copy_directory(dirfd(d), de->d_name, &buf, fdt, de->d_name, original_device, merge);
318 else if (S_ISLNK(buf.st_mode))
319 q = fd_copy_symlink(dirfd(d), de->d_name, &buf, fdt, de->d_name);
320 else if (S_ISFIFO(buf.st_mode))
321 q = fd_copy_fifo(dirfd(d), de->d_name, &buf, fdt, de->d_name);
322 else if (S_ISBLK(buf.st_mode) || S_ISCHR(buf.st_mode))
323 q = fd_copy_node(dirfd(d), de->d_name, &buf, fdt, de->d_name);
327 if (q == -EEXIST && merge)
337 int copy_tree_at(int fdf, const char *from, int fdt, const char *to, bool merge) {
343 if (fstatat(fdf, from, &st, AT_SYMLINK_NOFOLLOW) < 0)
346 if (S_ISREG(st.st_mode))
347 return fd_copy_regular(fdf, from, &st, fdt, to);
348 else if (S_ISDIR(st.st_mode))
349 return fd_copy_directory(fdf, from, &st, fdt, to, st.st_dev, merge);
350 else if (S_ISLNK(st.st_mode))
351 return fd_copy_symlink(fdf, from, &st, fdt, to);
352 else if (S_ISFIFO(st.st_mode))
353 return fd_copy_fifo(fdf, from, &st, fdt, to);
354 else if (S_ISBLK(st.st_mode) || S_ISCHR(st.st_mode))
355 return fd_copy_node(fdf, from, &st, fdt, to);
360 int copy_tree(const char *from, const char *to, bool merge) {
361 return copy_tree_at(AT_FDCWD, from, AT_FDCWD, to, merge);
364 int copy_directory_fd(int dirfd, const char *to, bool merge) {
371 if (fstat(dirfd, &st) < 0)
374 if (!S_ISDIR(st.st_mode))
377 return fd_copy_directory(dirfd, NULL, &st, AT_FDCWD, to, st.st_dev, merge);
380 int copy_file_fd(const char *from, int fdt, bool try_reflink) {
381 _cleanup_close_ int fdf = -1;
387 fdf = open(from, O_RDONLY|O_CLOEXEC|O_NOCTTY);
391 r = copy_bytes(fdf, fdt, (uint64_t) -1, try_reflink);
393 (void) copy_times(fdf, fdt);
394 (void) copy_xattr(fdf, fdt);
399 int copy_file(const char *from, const char *to, int flags, mode_t mode, unsigned chattr_flags) {
405 RUN_WITH_UMASK(0000) {
406 fdt = open(to, flags|O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY, mode);
411 if (chattr_flags != 0)
412 (void) chattr_fd(fdt, chattr_flags, (unsigned) -1);
414 r = copy_file_fd(from, fdt, true);
421 if (close(fdt) < 0) {
429 int copy_file_atomic(const char *from, const char *to, mode_t mode, bool replace, unsigned chattr_flags) {
430 _cleanup_free_ char *t = NULL;
436 r = tempfn_random(to, NULL, &t);
440 r = copy_file(from, t, O_NOFOLLOW|O_EXCL, mode, chattr_flags);
445 r = renameat(AT_FDCWD, t, AT_FDCWD, to);
449 r = rename_noreplace(AT_FDCWD, t, AT_FDCWD, to);
451 (void) unlink_noerrno(t);
458 int copy_times(int fdf, int fdt) {
459 struct timespec ut[2];
466 if (fstat(fdf, &st) < 0)
472 if (futimens(fdt, ut) < 0)
475 if (fd_getcrtime(fdf, &crtime) >= 0)
476 (void) fd_setcrtime(fdt, crtime);
481 int copy_xattr(int fdf, int fdt) {
482 _cleanup_free_ char *bufa = NULL, *bufb = NULL;
483 size_t sza = 100, szb = 100;
493 n = flistxattr(fdf, bufa, sza);
511 assert(l < (size_t) n);
513 if (startswith(p, "user.")) {
522 m = fgetxattr(fdf, p, bufb, szb);
524 if (errno == ERANGE) {
533 if (fsetxattr(fdt, p, bufb, m, 0) < 0)