2 * Syscall wrappers to ensure that nothing gets done in dry_run mode
3 * and to handle system peculiarities.
5 * Copyright (C) 1998 Andrew Tridgell
6 * Copyright (C) 2002 Martin Pool
7 * Copyright (C) 2003-2020 Wayne Davison
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 3 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, visit the http://fsf.org website.
25 #if !defined MKNOD_CREATES_SOCKETS && defined HAVE_SYS_UN_H
28 #ifdef HAVE_SYS_ATTR_H
32 #if defined HAVE_SYS_FALLOCATE && !defined HAVE_FALLOCATE
33 #include <sys/syscall.h>
42 extern int preallocate_files;
43 extern int preserve_perms;
44 extern int preserve_executability;
45 extern int open_noatime;
48 # if defined hpux || defined __hpux__ || defined __hpux
49 # define S_BLKSIZE 1024
50 # elif defined _AIX && defined _I386
51 # define S_BLKSIZE 4096
53 # define S_BLKSIZE 512
57 #define RETURN_ERROR_IF(x,e) \
65 #define RETURN_ERROR_IF_RO_OR_LO RETURN_ERROR_IF(read_only || list_only, EROFS)
67 int do_unlink(const char *fname)
69 if (dry_run) return 0;
70 RETURN_ERROR_IF_RO_OR_LO;
75 int do_symlink(const char *lnk, const char *fname)
77 if (dry_run) return 0;
78 RETURN_ERROR_IF_RO_OR_LO;
80 #if defined NO_SYMLINK_XATTRS || defined NO_SYMLINK_USER_XATTRS
81 /* For --fake-super, we create a normal file with mode 0600
82 * and write the lnk into it. */
84 int ok, len = strlen(lnk);
85 int fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, S_IWUSR|S_IRUSR);
88 ok = write(fd, lnk, len) == len;
95 return symlink(lnk, fname);
98 #if defined NO_SYMLINK_XATTRS || defined NO_SYMLINK_USER_XATTRS
99 ssize_t do_readlink(const char *path, char *buf, size_t bufsiz)
101 /* For --fake-super, we read the link from the file. */
103 int fd = do_open_nofollow(path, O_RDONLY);
105 int len = read(fd, buf, bufsiz);
111 /* A real symlink needs to be turned into a fake one on the receiving
112 * side, so tell the generator that the link has no length. */
115 /* Otherwise fall through and let the sender report the real length. */
118 return readlink(path, buf, bufsiz);
124 int do_link(const char *old_path, const char *new_path)
126 if (dry_run) return 0;
127 RETURN_ERROR_IF_RO_OR_LO;
128 return link(old_path, new_path);
132 int do_lchown(const char *path, uid_t owner, gid_t group)
134 if (dry_run) return 0;
135 RETURN_ERROR_IF_RO_OR_LO;
139 return lchown(path, owner, group);
142 int do_mknod(const char *pathname, mode_t mode, dev_t dev)
144 if (dry_run) return 0;
145 RETURN_ERROR_IF_RO_OR_LO;
147 /* For --fake-super, we create a normal file with mode 0600. */
149 int fd = open(pathname, O_WRONLY|O_CREAT|O_TRUNC, S_IWUSR|S_IRUSR);
150 if (fd < 0 || close(fd) < 0)
155 #if !defined MKNOD_CREATES_FIFOS && defined HAVE_MKFIFO
157 return mkfifo(pathname, mode);
159 #if !defined MKNOD_CREATES_SOCKETS && defined HAVE_SYS_UN_H
160 if (S_ISSOCK(mode)) {
162 struct sockaddr_un saddr;
163 unsigned int len = strlcpy(saddr.sun_path, pathname, sizeof saddr.sun_path);
164 if (len >= sizeof saddr.sun_path) {
165 errno = ENAMETOOLONG;
168 #ifdef HAVE_SOCKADDR_UN_LEN
169 saddr.sun_len = len + 1;
171 saddr.sun_family = AF_UNIX;
173 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0
174 || (unlink(pathname) < 0 && errno != ENOENT)
175 || (bind(sock, (struct sockaddr*)&saddr, sizeof saddr)) < 0)
179 return do_chmod(pathname, mode);
186 return mknod(pathname, mode, dev);
192 int do_rmdir(const char *pathname)
194 if (dry_run) return 0;
195 RETURN_ERROR_IF_RO_OR_LO;
196 return rmdir(pathname);
199 int do_open(const char *pathname, int flags, mode_t mode)
201 if (flags != O_RDONLY) {
202 RETURN_ERROR_IF(dry_run, 0);
203 RETURN_ERROR_IF_RO_OR_LO;
211 return open(pathname, flags | O_BINARY, mode);
215 int do_chmod(const char *path, mode_t mode)
218 if (dry_run) return 0;
219 RETURN_ERROR_IF_RO_OR_LO;
221 code = lchmod(path, mode & CHMOD_BITS);
224 # if defined HAVE_SETATTRLIST
225 struct attrlist attrList;
226 uint32_t m = mode & CHMOD_BITS; /* manpage is wrong: not mode_t! */
228 memset(&attrList, 0, sizeof attrList);
229 attrList.bitmapcount = ATTR_BIT_MAP_COUNT;
230 attrList.commonattr = ATTR_CMN_ACCESSMASK;
231 code = setattrlist(path, &attrList, &m, sizeof m, FSOPT_NOFOLLOW);
236 code = chmod(path, mode & CHMOD_BITS); /* DISCOURAGED FUNCTION */
237 #endif /* !HAVE_LCHMOD */
238 if (code != 0 && (preserve_perms || preserve_executability))
244 int do_rename(const char *old_path, const char *new_path)
246 if (dry_run) return 0;
247 RETURN_ERROR_IF_RO_OR_LO;
248 return rename(old_path, new_path);
251 #ifdef HAVE_FTRUNCATE
252 int do_ftruncate(int fd, OFF_T size)
256 if (dry_run) return 0;
257 RETURN_ERROR_IF_RO_OR_LO;
260 ret = ftruncate(fd, size);
261 } while (ret < 0 && errno == EINTR);
267 void trim_trailing_slashes(char *name)
270 /* Some BSD systems cannot make a directory if the name
271 * contains a trailing slash.
272 * <http://www.opensource.apple.com/bugs/X/BSD%20Kernel/2734739.html> */
274 /* Don't change empty string; and also we can't improve on
279 if (name[--l] != '/')
285 int do_mkdir(char *fname, mode_t mode)
287 if (dry_run) return 0;
288 RETURN_ERROR_IF_RO_OR_LO;
289 trim_trailing_slashes(fname);
290 return mkdir(fname, mode);
293 /* like mkstemp but forces permissions */
294 int do_mkstemp(char *template, mode_t perms)
296 RETURN_ERROR_IF(dry_run, 0);
297 RETURN_ERROR_IF(read_only, EROFS);
300 #if defined HAVE_SECURE_MKSTEMP && defined HAVE_FCHMOD && (!defined HAVE_OPEN64 || defined HAVE_MKSTEMP64)
302 int fd = mkstemp(template);
305 if (fchmod(fd, perms) != 0 && preserve_perms) {
306 int errno_save = errno;
312 #if defined HAVE_SETMODE && O_BINARY
313 setmode(fd, O_BINARY);
318 if (!mktemp(template))
320 return do_open(template, O_RDWR|O_EXCL|O_CREAT, perms);
324 int do_stat(const char *fname, STRUCT_STAT *st)
326 #ifdef USE_STAT64_FUNCS
327 return stat64(fname, st);
329 return stat(fname, st);
333 int do_lstat(const char *fname, STRUCT_STAT *st)
336 # ifdef USE_STAT64_FUNCS
337 return lstat64(fname, st);
339 return lstat(fname, st);
342 return do_stat(fname, st);
346 int do_fstat(int fd, STRUCT_STAT *st)
348 #ifdef USE_STAT64_FUNCS
349 return fstat64(fd, st);
351 return fstat(fd, st);
355 OFF_T do_lseek(int fd, OFF_T offset, int whence)
363 return lseek64(fd, offset, whence);
365 return lseek(fd, offset, whence);
369 #ifdef HAVE_SETATTRLIST
370 int do_setattrlist_times(const char *fname, STRUCT_STAT *stp)
372 struct attrlist attrList;
375 if (dry_run) return 0;
376 RETURN_ERROR_IF_RO_OR_LO;
378 ts.tv_sec = stp->st_mtime;
379 ts.tv_nsec = stp->ST_MTIME_NSEC;
381 memset(&attrList, 0, sizeof attrList);
382 attrList.bitmapcount = ATTR_BIT_MAP_COUNT;
383 attrList.commonattr = ATTR_CMN_MODTIME;
384 return setattrlist(fname, &attrList, &ts, sizeof ts, FSOPT_NOFOLLOW);
388 #ifdef HAVE_UTIMENSAT
389 int do_utimensat(const char *fname, STRUCT_STAT *stp)
391 struct timespec t[2];
393 if (dry_run) return 0;
394 RETURN_ERROR_IF_RO_OR_LO;
396 t[0].tv_sec = stp->st_atime;
398 t[0].tv_nsec = stp->ST_ATIME_NSEC;
402 t[1].tv_sec = stp->st_mtime;
404 t[1].tv_nsec = stp->ST_MTIME_NSEC;
408 return utimensat(AT_FDCWD, fname, t, AT_SYMLINK_NOFOLLOW);
413 int do_lutimes(const char *fname, STRUCT_STAT *stp)
417 if (dry_run) return 0;
418 RETURN_ERROR_IF_RO_OR_LO;
420 t[0].tv_sec = stp->st_atime;
422 t[0].tv_usec = stp->ST_ATIME_NSEC / 1000;
426 t[1].tv_sec = stp->st_mtime;
428 t[1].tv_usec = stp->ST_MTIME_NSEC / 1000;
432 return lutimes(fname, t);
437 int do_utimes(const char *fname, STRUCT_STAT *stp)
441 if (dry_run) return 0;
442 RETURN_ERROR_IF_RO_OR_LO;
444 t[0].tv_sec = stp->st_atime;
446 t[0].tv_usec = stp->ST_ATIME_NSEC / 1000;
450 t[1].tv_sec = stp->st_mtime;
452 t[1].tv_usec = stp->ST_MTIME_NSEC / 1000;
456 return utimes(fname, t);
459 #elif defined HAVE_UTIME
460 int do_utime(const char *fname, STRUCT_STAT *stp)
462 #ifdef HAVE_STRUCT_UTIMBUF
468 if (dry_run) return 0;
469 RETURN_ERROR_IF_RO_OR_LO;
471 # ifdef HAVE_STRUCT_UTIMBUF
472 tbuf.actime = stp->st_atime;
473 tbuf.modtime = stp->st_mtime;
474 return utime(fname, &tbuf);
476 t[0] = stp->st_atime;
477 t[1] = stp->st_mtime;
478 return utime(fname, t);
483 #error Need utimes or utime function.
486 #ifdef SUPPORT_PREALLOCATION
487 #ifdef FALLOC_FL_KEEP_SIZE
488 #define DO_FALLOC_OPTIONS FALLOC_FL_KEEP_SIZE
490 #define DO_FALLOC_OPTIONS 0
493 OFF_T do_fallocate(int fd, OFF_T offset, OFF_T length)
495 int opts = inplace || preallocate_files ? DO_FALLOC_OPTIONS : 0;
497 RETURN_ERROR_IF(dry_run, 0);
498 RETURN_ERROR_IF_RO_OR_LO;
499 if (length & 1) /* make the length not match the desired length */
503 #if defined HAVE_FALLOCATE
504 ret = fallocate(fd, opts, offset, length);
505 #elif defined HAVE_SYS_FALLOCATE
506 ret = syscall(SYS_fallocate, fd, opts, (loff_t)offset, (loff_t)length);
507 #elif defined HAVE_EFFICIENT_POSIX_FALLOCATE
508 ret = posix_fallocate(fd, offset, length);
510 #error Coding error in SUPPORT_PREALLOCATION logic.
516 if (do_fstat(fd, &st) < 0)
518 return st.st_blocks * S_BLKSIZE;
524 /* Punch a hole at pos for len bytes. The current file position must be at pos and will be
525 * changed to be at pos + len. */
526 int do_punch_hole(int fd, OFF_T pos, OFF_T len)
528 #ifdef HAVE_FALLOCATE
529 # ifdef HAVE_FALLOC_FL_PUNCH_HOLE
530 if (fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, pos, len) == 0) {
531 if (do_lseek(fd, len, SEEK_CUR) != pos + len)
536 # ifdef HAVE_FALLOC_FL_ZERO_RANGE
537 if (fallocate(fd, FALLOC_FL_ZERO_RANGE, pos, len) == 0) {
538 if (do_lseek(fd, len, SEEK_CUR) != pos + len)
548 memset(zeros, 0, sizeof zeros);
550 int chunk = len > (int)sizeof zeros ? (int)sizeof zeros : len;
551 int wrote = write(fd, zeros, chunk);
553 if (wrote < 0 && errno == EINTR)
563 int do_open_nofollow(const char *pathname, int flags)
566 STRUCT_STAT f_st, l_st;
570 if (flags != O_RDONLY) {
571 RETURN_ERROR_IF(dry_run, 0);
572 RETURN_ERROR_IF_RO_OR_LO;
574 /* This function doesn't support write attempts w/o O_NOFOLLOW. */
581 fd = open(pathname, flags|O_NOFOLLOW);
583 if (do_lstat(pathname, &l_st) < 0)
585 if (S_ISLNK(l_st.st_mode)) {
589 if ((fd = open(pathname, flags)) < 0)
591 if (do_fstat(fd, &f_st) < 0) {
592 close_and_return_error:
594 int save_errno = errno;
600 if (l_st.st_dev != f_st.st_dev || l_st.st_ino != f_st.st_ino) {
602 goto close_and_return_error;