1 /* -*- buffer-read-only: t -*- vi: set ro: */
2 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */
3 /* Define at-style functions like fstatat, unlinkat, fchownat, etc.
4 Copyright (C) 2006, 2009-2013 Free Software Foundation, Inc.
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 /* written by Jim Meyering */
21 #include "dosname.h" /* solely for definition of IS_ABSOLUTE_FILE_NAME */
23 #ifdef GNULIB_SUPPORT_ONLY_AT_FDCWD
26 # define ENOTSUP EINVAL
30 # include "openat-priv.h"
31 # include "save-cwd.h"
34 #ifdef AT_FUNC_USE_F1_COND
35 # define CALL_FUNC(F) \
36 (flag == AT_FUNC_USE_F1_COND \
37 ? AT_FUNC_F1 (F AT_FUNC_POST_FILE_ARGS) \
38 : AT_FUNC_F2 (F AT_FUNC_POST_FILE_ARGS))
39 # define VALIDATE_FLAG(F) \
40 if (flag & ~AT_FUNC_USE_F1_COND) \
46 # define CALL_FUNC(F) (AT_FUNC_F1 (F AT_FUNC_POST_FILE_ARGS))
47 # define VALIDATE_FLAG(F) /* empty */
51 # define FUNC_RESULT AT_FUNC_RESULT
53 # define FUNC_RESULT int
57 # define FUNC_FAIL AT_FUNC_FAIL
62 /* Call AT_FUNC_F1 to operate on FILE, which is in the directory
63 open on descriptor FD. If AT_FUNC_USE_F1_COND is defined to a value,
64 AT_FUNC_POST_FILE_PARAM_DECLS must include a parameter named flag;
65 call AT_FUNC_F2 if FLAG is 0 or fail if FLAG contains more bits than
66 AT_FUNC_USE_F1_COND. Return int and fail with -1 unless AT_FUNC_RESULT
67 or AT_FUNC_FAIL are defined. If possible, do it without changing the
68 working directory. Otherwise, resort to using save_cwd/fchdir,
69 then AT_FUNC_F?/restore_cwd. If either the save_cwd or the restore_cwd
70 fails, then give a diagnostic and exit nonzero. */
72 AT_FUNC_NAME (int fd, char const *file AT_FUNC_POST_FILE_PARAM_DECLS)
76 if (fd == AT_FDCWD || IS_ABSOLUTE_FILE_NAME (file))
77 return CALL_FUNC (file);
79 #ifdef GNULIB_SUPPORT_ONLY_AT_FDCWD
84 /* Be careful to choose names unlikely to conflict with
85 AT_FUNC_POST_FILE_PARAM_DECLS. */
86 struct saved_cwd saved_cwd;
91 char proc_buf[OPENAT_BUFFER_SIZE];
92 char *proc_file = openat_proc_name (proc_buf, fd, file);
95 FUNC_RESULT proc_result = CALL_FUNC (proc_file);
96 int proc_errno = errno;
97 if (proc_file != proc_buf)
99 /* If the syscall succeeds, or if it fails with an unexpected
100 errno value, then return right away. Otherwise, fall through
101 and resort to using save_cwd/restore_cwd. */
102 if (FUNC_FAIL != proc_result)
104 if (! EXPECTED_ERRNO (proc_errno))
112 if (save_cwd (&saved_cwd) != 0)
113 openat_save_fail (errno);
114 if (0 <= fd && fd == saved_cwd.desc)
116 /* If saving the working directory collides with the user's
117 requested fd, then the user's fd must have been closed to
119 free_cwd (&saved_cwd);
124 if (fchdir (fd) != 0)
127 free_cwd (&saved_cwd);
132 err = CALL_FUNC (file);
133 saved_errno = (err == FUNC_FAIL ? errno : 0);
135 if (restore_cwd (&saved_cwd) != 0)
136 openat_restore_fail (errno);
138 free_cwd (&saved_cwd);