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a346370d58
(__readlinkat_alias): New alias. (readlinkat): New inline function. * include/unistd.h (readlinkat): Add libc_hidden_proto. * sysdeps/unix/sysv/linux/readlinkat.c (readlinkat): Add libc_hidden_def. * io/readlinkat.c (readlinkat): Likewise. * debug/readlinkat_chk.c: New file. * debug/Makefile (routines): Add readlinkat_chk. * debug/Versions (libc): Export __readlinkat_chk@@GLIBC_2.5. * debug/tst-chk1.c (do_test): Add readlinkat tests. * nis/nss_nisplus/nisplus-netgrp.c: Cleanups. code is possible. Move compatibility code in .text.compat section. over gaih array. There is only one function to call in the moment.
91 lines
2.5 KiB
C
91 lines
2.5 KiB
C
/* Copyright (C) 2005, 2006 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library 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 GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <errno.h>
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#include <fcntl.h>
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#include <stddef.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sysdep.h>
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#include <unistd.h>
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#include <kernel-features.h>
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/* Read the contents of the symbolic link PATH relative to FD into no
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more than LEN bytes of BUF. */
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ssize_t
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readlinkat (fd, path, buf, len)
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int fd;
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const char *path;
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char *buf;
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size_t len;
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{
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int result;
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#ifdef __NR_readlinkat
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# ifndef __ASSUME_ATFCTS
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if (__have_atfcts >= 0)
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# endif
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{
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result = INLINE_SYSCALL (readlinkat, 4, fd, path, buf, len);
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# ifndef __ASSUME_ATFCTS
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if (result == -1 && errno == ENOSYS)
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__have_atfcts = -1;
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else
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# endif
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return result;
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}
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#endif
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#ifndef __ASSUME_ATFCTS
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char *pathbuf = NULL;
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if (fd != AT_FDCWD && path[0] != '/')
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{
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size_t pathlen = strlen (path);
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static const char procfd[] = "/proc/self/fd/%d/%s";
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/* Buffer for the path 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. A bit of overhead
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due to the format elements compensates for possible negative
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numbers. */
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size_t buflen = sizeof (procfd) + sizeof (int) * 3 + pathlen;
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pathbuf = __alloca (buflen);
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__snprintf (pathbuf, buflen, procfd, fd, path);
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path = pathbuf;
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}
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INTERNAL_SYSCALL_DECL (err);
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result = INTERNAL_SYSCALL (readlink, err, 3, path, buf, len);
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if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0))
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{
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__atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, pathbuf);
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result = -1;
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}
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return result;
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#endif
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}
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libc_hidden_def (readlinkat)
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