diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/symlinkat.c')
-rw-r--r-- | sysdeps/unix/sysv/linux/symlinkat.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/symlinkat.c b/sysdeps/unix/sysv/linux/symlinkat.c new file mode 100644 index 0000000000..211b49c299 --- /dev/null +++ b/sysdeps/unix/sysv/linux/symlinkat.c @@ -0,0 +1,67 @@ +/* Copyright (C) 2005 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <errno.h> +#include <fcntl.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sysdep.h> +#include <unistd.h> + + +/* Make a symbolic link to FROM named TO relative to TOFD. */ +int +symlinkat (from, tofd, to) + const char *from; + int tofd; + const char *to; +{ + char *buf = NULL; + + if (tofd != AT_FDCWD && to[0] != '/') + { + size_t tolen = strlen (to); + static const char procfd[] = "/proc/self/fd/%d/%s"; + /* Buffer for the path name we are going to use. It consists of + - the string /proc/self/fd/ + - the file descriptor number + - the file name provided. + The final NUL is included in the sizeof. A bit of overhead + due to the format elements compensates for possible negative + numbers. */ + size_t buflen = sizeof (procfd) + sizeof (int) * 3 + tolen; + buf = __alloca (buflen); + + __snprintf (buf, buflen, procfd, tofd, to); + to = buf; + } + + INTERNAL_SYSCALL_DECL (err); + + int result = INTERNAL_SYSCALL (symlink, err, 2, from, to); + + if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0)) + { + __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), tofd, buf); + result = -1; + } + + return result; +} |