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6a33c69c49
Paul Eggert reported that unlink/rmdir vs. e.g., /proc/self/fd/N/FILE fails with ENOSYS. This makes openat revert to using save-cwd.c functions in that case.
53 lines
2.2 KiB
C
53 lines
2.2 KiB
C
/* macros used by openat-like functions
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Copyright (C) 2005 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software Foundation,
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Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
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/* written by Jim Meyering */
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#include <stdio.h>
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#include <string.h>
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#include "alloca.h"
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#include "intprops.h"
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/* Set PROC_FD_FILENAME to the expansion of "/proc/self/fd/%d/%s" in
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alloca'd memory, using FD and FILE, respectively for %d and %s. */
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#define BUILD_PROC_NAME(Proc_fd_filename, Fd, File) \
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do \
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{ \
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size_t filelen = strlen (File); \
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static const char procfd[] = "/proc/self/fd/%d/%s"; \
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/* Buffer for the file name we are going to use. It consists of \
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- the string /proc/self/fd/ \
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- the file descriptor number \
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- the file name provided. \
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The final NUL is included in the sizeof. \
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Subtract 4 to account for %d and %s. */ \
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size_t buflen = sizeof (procfd) - 4 + INT_STRLEN_BOUND (Fd) + filelen; \
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(Proc_fd_filename) = alloca (buflen); \
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snprintf ((Proc_fd_filename), buflen, procfd, (Fd), (File)); \
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} \
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while (0)
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/* Trying to access a BUILD_PROC_NAME file will fail on systems without
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/proc support, and even on systems *with* ProcFS support. Return
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nonzero if the failure may be legitimate, e.g., because /proc is not
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readable, or the particular .../fd/N directory is not present. */
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#define EXPECTED_ERRNO(Errno) \
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((Errno) == ENOTDIR || (Errno) == ENOENT \
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|| (Errno) == EPERM || (Errno) == EACCES \
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|| (Errno) == ENOSYS /* Solaris 8 */ \
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|| (Errno) == EOPNOTSUPP /* FreeBSD */)
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