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 #ifdef SUPPORT_CRTIMES
61 struct timespec crtime;
66 #define RETURN_ERROR_IF(x,e) \
74 #define RETURN_ERROR_IF_RO_OR_LO RETURN_ERROR_IF(read_only || list_only, EROFS)
76 int do_unlink(const char *fname)
78 if (dry_run) return 0;
79 RETURN_ERROR_IF_RO_OR_LO;
84 int do_symlink(const char *lnk, const char *fname)
86 if (dry_run) return 0;
87 RETURN_ERROR_IF_RO_OR_LO;
89 #if defined NO_SYMLINK_XATTRS || defined NO_SYMLINK_USER_XATTRS
90 /* For --fake-super, we create a normal file with mode 0600
91 * and write the lnk into it. */
93 int ok, len = strlen(lnk);
94 int fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, S_IWUSR|S_IRUSR);
97 ok = write(fd, lnk, len) == len;
104 return symlink(lnk, fname);
107 #if defined NO_SYMLINK_XATTRS || defined NO_SYMLINK_USER_XATTRS
108 ssize_t do_readlink(const char *path, char *buf, size_t bufsiz)
110 /* For --fake-super, we read the link from the file. */
112 int fd = do_open_nofollow(path, O_RDONLY);
114 int len = read(fd, buf, bufsiz);
120 /* A real symlink needs to be turned into a fake one on the receiving
121 * side, so tell the generator that the link has no length. */
124 /* Otherwise fall through and let the sender report the real length. */
127 return readlink(path, buf, bufsiz);
133 int do_link(const char *old_path, const char *new_path)
135 if (dry_run) return 0;
136 RETURN_ERROR_IF_RO_OR_LO;
137 return link(old_path, new_path);
141 int do_lchown(const char *path, uid_t owner, gid_t group)
143 if (dry_run) return 0;
144 RETURN_ERROR_IF_RO_OR_LO;
148 return lchown(path, owner, group);
151 int do_mknod(const char *pathname, mode_t mode, dev_t dev)
153 if (dry_run) return 0;
154 RETURN_ERROR_IF_RO_OR_LO;
156 /* For --fake-super, we create a normal file with mode 0600. */
158 int fd = open(pathname, O_WRONLY|O_CREAT|O_TRUNC, S_IWUSR|S_IRUSR);
159 if (fd < 0 || close(fd) < 0)
164 #if !defined MKNOD_CREATES_FIFOS && defined HAVE_MKFIFO
166 return mkfifo(pathname, mode);
168 #if !defined MKNOD_CREATES_SOCKETS && defined HAVE_SYS_UN_H
169 if (S_ISSOCK(mode)) {
171 struct sockaddr_un saddr;
172 unsigned int len = strlcpy(saddr.sun_path, pathname, sizeof saddr.sun_path);
173 if (len >= sizeof saddr.sun_path) {
174 errno = ENAMETOOLONG;
177 #ifdef HAVE_SOCKADDR_UN_LEN
178 saddr.sun_len = len + 1;
180 saddr.sun_family = AF_UNIX;
182 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0
183 || (unlink(pathname) < 0 && errno != ENOENT)
184 || (bind(sock, (struct sockaddr*)&saddr, sizeof saddr)) < 0)
188 return do_chmod(pathname, mode);
195 return mknod(pathname, mode, dev);
201 int do_rmdir(const char *pathname)
203 if (dry_run) return 0;
204 RETURN_ERROR_IF_RO_OR_LO;
205 return rmdir(pathname);
208 int do_open(const char *pathname, int flags, mode_t mode)
210 if (flags != O_RDONLY) {
211 RETURN_ERROR_IF(dry_run, 0);
212 RETURN_ERROR_IF_RO_OR_LO;
220 return open(pathname, flags | O_BINARY, mode);
224 int do_chmod(const char *path, mode_t mode)
227 if (dry_run) return 0;
228 RETURN_ERROR_IF_RO_OR_LO;
230 code = lchmod(path, mode & CHMOD_BITS);
233 # if defined HAVE_SETATTRLIST
234 struct attrlist attrList;
235 uint32_t m = mode & CHMOD_BITS; /* manpage is wrong: not mode_t! */
237 memset(&attrList, 0, sizeof attrList);
238 attrList.bitmapcount = ATTR_BIT_MAP_COUNT;
239 attrList.commonattr = ATTR_CMN_ACCESSMASK;
240 code = setattrlist(path, &attrList, &m, sizeof m, FSOPT_NOFOLLOW);
245 code = chmod(path, mode & CHMOD_BITS); /* DISCOURAGED FUNCTION */
246 #endif /* !HAVE_LCHMOD */
247 if (code != 0 && (preserve_perms || preserve_executability))
253 int do_rename(const char *old_path, const char *new_path)
255 if (dry_run) return 0;
256 RETURN_ERROR_IF_RO_OR_LO;
257 return rename(old_path, new_path);
260 #ifdef HAVE_FTRUNCATE
261 int do_ftruncate(int fd, OFF_T size)
265 if (dry_run) return 0;
266 RETURN_ERROR_IF_RO_OR_LO;
269 ret = ftruncate(fd, size);
270 } while (ret < 0 && errno == EINTR);
276 void trim_trailing_slashes(char *name)
279 /* Some BSD systems cannot make a directory if the name
280 * contains a trailing slash.
281 * <http://www.opensource.apple.com/bugs/X/BSD%20Kernel/2734739.html> */
283 /* Don't change empty string; and also we can't improve on
288 if (name[--l] != '/')
294 int do_mkdir(char *fname, mode_t mode)
296 if (dry_run) return 0;
297 RETURN_ERROR_IF_RO_OR_LO;
298 trim_trailing_slashes(fname);
299 return mkdir(fname, mode);
302 /* like mkstemp but forces permissions */
303 int do_mkstemp(char *template, mode_t perms)
305 RETURN_ERROR_IF(dry_run, 0);
306 RETURN_ERROR_IF(read_only, EROFS);
309 #if defined HAVE_SECURE_MKSTEMP && defined HAVE_FCHMOD && (!defined HAVE_OPEN64 || defined HAVE_MKSTEMP64)
311 int fd = mkstemp(template);
314 if (fchmod(fd, perms) != 0 && preserve_perms) {
315 int errno_save = errno;
321 #if defined HAVE_SETMODE && O_BINARY
322 setmode(fd, O_BINARY);
327 if (!mktemp(template))
329 return do_open(template, O_RDWR|O_EXCL|O_CREAT, perms);
333 int do_stat(const char *fname, STRUCT_STAT *st)
335 #ifdef USE_STAT64_FUNCS
336 return stat64(fname, st);
338 return stat(fname, st);
342 int do_lstat(const char *fname, STRUCT_STAT *st)
345 # ifdef USE_STAT64_FUNCS
346 return lstat64(fname, st);
348 return lstat(fname, st);
351 return do_stat(fname, st);
355 int do_fstat(int fd, STRUCT_STAT *st)
357 #ifdef USE_STAT64_FUNCS
358 return fstat64(fd, st);
360 return fstat(fd, st);
364 OFF_T do_lseek(int fd, OFF_T offset, int whence)
372 return lseek64(fd, offset, whence);
374 return lseek(fd, offset, whence);
378 #ifdef HAVE_SETATTRLIST
379 int do_setattrlist_times(const char *fname, STRUCT_STAT *stp)
381 struct attrlist attrList;
384 if (dry_run) return 0;
385 RETURN_ERROR_IF_RO_OR_LO;
387 ts.tv_sec = stp->st_mtime;
388 ts.tv_nsec = stp->ST_MTIME_NSEC;
390 memset(&attrList, 0, sizeof attrList);
391 attrList.bitmapcount = ATTR_BIT_MAP_COUNT;
392 attrList.commonattr = ATTR_CMN_MODTIME;
393 return setattrlist(fname, &attrList, &ts, sizeof ts, FSOPT_NOFOLLOW);
397 #ifdef SUPPORT_CRTIMES
398 time_t get_create_time(const char *path)
400 static struct create_time attrBuf;
401 struct attrlist attrList;
403 memset(&attrList, 0, sizeof attrList);
404 attrList.bitmapcount = ATTR_BIT_MAP_COUNT;
405 attrList.commonattr = ATTR_CMN_CRTIME;
406 if (getattrlist(path, &attrList, &attrBuf, sizeof attrBuf, FSOPT_NOFOLLOW) < 0)
408 return attrBuf.crtime.tv_sec;
412 #ifdef SUPPORT_CRTIMES
413 int set_create_time(const char *path, time_t crtime)
415 struct attrlist attrList;
418 if (dry_run) return 0;
419 RETURN_ERROR_IF_RO_OR_LO;
424 memset(&attrList, 0, sizeof attrList);
425 attrList.bitmapcount = ATTR_BIT_MAP_COUNT;
426 attrList.commonattr = ATTR_CMN_CRTIME;
427 return setattrlist(path, &attrList, &ts, sizeof ts, FSOPT_NOFOLLOW);
431 #ifdef HAVE_UTIMENSAT
432 int do_utimensat(const char *fname, STRUCT_STAT *stp)
434 struct timespec t[2];
436 if (dry_run) return 0;
437 RETURN_ERROR_IF_RO_OR_LO;
439 t[0].tv_sec = stp->st_atime;
441 t[0].tv_nsec = stp->ST_ATIME_NSEC;
445 t[1].tv_sec = stp->st_mtime;
447 t[1].tv_nsec = stp->ST_MTIME_NSEC;
451 return utimensat(AT_FDCWD, fname, t, AT_SYMLINK_NOFOLLOW);
456 int do_lutimes(const char *fname, STRUCT_STAT *stp)
460 if (dry_run) return 0;
461 RETURN_ERROR_IF_RO_OR_LO;
463 t[0].tv_sec = stp->st_atime;
465 t[0].tv_usec = stp->ST_ATIME_NSEC / 1000;
469 t[1].tv_sec = stp->st_mtime;
471 t[1].tv_usec = stp->ST_MTIME_NSEC / 1000;
475 return lutimes(fname, t);
480 int do_utimes(const char *fname, STRUCT_STAT *stp)
484 if (dry_run) return 0;
485 RETURN_ERROR_IF_RO_OR_LO;
487 t[0].tv_sec = stp->st_atime;
489 t[0].tv_usec = stp->ST_ATIME_NSEC / 1000;
493 t[1].tv_sec = stp->st_mtime;
495 t[1].tv_usec = stp->ST_MTIME_NSEC / 1000;
499 return utimes(fname, t);
502 #elif defined HAVE_UTIME
503 int do_utime(const char *fname, STRUCT_STAT *stp)
505 #ifdef HAVE_STRUCT_UTIMBUF
511 if (dry_run) return 0;
512 RETURN_ERROR_IF_RO_OR_LO;
514 # ifdef HAVE_STRUCT_UTIMBUF
515 tbuf.actime = stp->st_atime;
516 tbuf.modtime = stp->st_mtime;
517 return utime(fname, &tbuf);
519 t[0] = stp->st_atime;
520 t[1] = stp->st_mtime;
521 return utime(fname, t);
526 #error Need utimes or utime function.
529 #ifdef SUPPORT_PREALLOCATION
530 #ifdef FALLOC_FL_KEEP_SIZE
531 #define DO_FALLOC_OPTIONS FALLOC_FL_KEEP_SIZE
533 #define DO_FALLOC_OPTIONS 0
536 OFF_T do_fallocate(int fd, OFF_T offset, OFF_T length)
538 int opts = inplace || preallocate_files ? DO_FALLOC_OPTIONS : 0;
540 RETURN_ERROR_IF(dry_run, 0);
541 RETURN_ERROR_IF_RO_OR_LO;
542 if (length & 1) /* make the length not match the desired length */
546 #if defined HAVE_FALLOCATE
547 ret = fallocate(fd, opts, offset, length);
548 #elif defined HAVE_SYS_FALLOCATE
549 ret = syscall(SYS_fallocate, fd, opts, (loff_t)offset, (loff_t)length);
550 #elif defined HAVE_EFFICIENT_POSIX_FALLOCATE
551 ret = posix_fallocate(fd, offset, length);
553 #error Coding error in SUPPORT_PREALLOCATION logic.
559 if (do_fstat(fd, &st) < 0)
561 return st.st_blocks * S_BLKSIZE;
567 /* Punch a hole at pos for len bytes. The current file position must be at pos and will be
568 * changed to be at pos + len. */
569 int do_punch_hole(int fd, OFF_T pos, OFF_T len)
571 #ifdef HAVE_FALLOCATE
572 # ifdef HAVE_FALLOC_FL_PUNCH_HOLE
573 if (fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, pos, len) == 0) {
574 if (do_lseek(fd, len, SEEK_CUR) != pos + len)
579 # ifdef HAVE_FALLOC_FL_ZERO_RANGE
580 if (fallocate(fd, FALLOC_FL_ZERO_RANGE, pos, len) == 0) {
581 if (do_lseek(fd, len, SEEK_CUR) != pos + len)
591 memset(zeros, 0, sizeof zeros);
593 int chunk = len > (int)sizeof zeros ? (int)sizeof zeros : len;
594 int wrote = write(fd, zeros, chunk);
596 if (wrote < 0 && errno == EINTR)
606 int do_open_nofollow(const char *pathname, int flags)
609 STRUCT_STAT f_st, l_st;
613 if (flags != O_RDONLY) {
614 RETURN_ERROR_IF(dry_run, 0);
615 RETURN_ERROR_IF_RO_OR_LO;
617 /* This function doesn't support write attempts w/o O_NOFOLLOW. */
624 fd = open(pathname, flags|O_NOFOLLOW);
626 if (do_lstat(pathname, &l_st) < 0)
628 if (S_ISLNK(l_st.st_mode)) {
632 if ((fd = open(pathname, flags)) < 0)
634 if (do_fstat(fd, &f_st) < 0) {
635 close_and_return_error:
637 int save_errno = errno;
643 if (l_st.st_dev != f_st.st_dev || l_st.st_ino != f_st.st_ino) {
645 goto close_and_return_error;