diff options
Diffstat (limited to 'libc/sysdeps/unix/sysv/linux/unlinkat.c')
-rw-r--r-- | libc/sysdeps/unix/sysv/linux/unlinkat.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/libc/sysdeps/unix/sysv/linux/unlinkat.c b/libc/sysdeps/unix/sysv/linux/unlinkat.c new file mode 100644 index 000000000..0a07a8a87 --- /dev/null +++ b/libc/sysdeps/unix/sysv/linux/unlinkat.c @@ -0,0 +1,97 @@ +/* unlinkat -- Remove a link by relative name. + Copyright (C) 2005, 2006 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> +#include <kernel-features.h> + + +/* Remove the link named NAME. */ +int +unlinkat (fd, file, flag) + int fd; + const char *file; + int flag; +{ + int result; + +#ifdef __NR_unlinkat +# ifndef __ASSUME_ATFCTS + if (__have_atfcts >= 0) +# endif + { + result = INLINE_SYSCALL (unlinkat, 3, fd, file, flag); +# ifndef __ASSUME_ATFCTS + if (result == -1 && errno == ENOSYS) + __have_atfcts = -1; + else +# endif + return result; + } +#endif + +#ifndef __ASSUME_ATFCTS + if (flag & ~AT_REMOVEDIR) + { + __set_errno (EINVAL); + return -1; + } + + char *buf = NULL; + + if (fd != AT_FDCWD && file[0] != '/') + { + size_t filelen = strlen (file); + 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 + filelen; + buf = __alloca (buflen); + + __snprintf (buf, buflen, procfd, fd, file); + file = buf; + } + + INTERNAL_SYSCALL_DECL (err); + + if (flag & AT_REMOVEDIR) + result = INTERNAL_SYSCALL (rmdir, err, 1, file); + else + result = INTERNAL_SYSCALL (unlink, err, 1, file); + + if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0)) + { + __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf); + result = -1; + } + + return result; +#endif +} |