ports/sysdeps/unix/sysv/linux/mips/mips64/fxstatat64.c

   1 /* Copyright (C) 2005,2006 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library.  If not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <fcntl.h>
  20 #include <stddef.h>
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include <sys/stat.h>
  24 #include <kernel_stat.h>
  25
  26 #include <sysdep.h>
  27 #include <sys/syscall.h>
  28 #include <bp-checks.h>
  29
  30 #include <kernel-features.h>
  31
  32 #include <xstatconv.h>
  33
  34 /* Get information about the file NAME in BUF.  */
  35
  36 int
  37 __fxstatat64 (int vers, int fd, const char *file, struct stat64 *st, int flag)
  38 {
  39   if (__builtin_expect (vers != _STAT_VER_LINUX, 0))
  40     {
  41       __set_errno (EINVAL);
  42       return -1;
  43     }
  44
  45   int result;
  46   INTERNAL_SYSCALL_DECL (err);
  47   struct kernel_stat kst;
  48
  49 #ifdef __NR_newfstatat
  50 # ifndef __ASSUME_ATFCTS
  51   if (__have_atfcts >= 0)
  52 # endif
  53     {
  54       result = INTERNAL_SYSCALL (newfstatat, err, 4, fd, file, &kst, flag);
  55 # ifndef __ASSUME_ATFCTS
  56       if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1)
  57           && INTERNAL_SYSCALL_ERRNO (result, err) == ENOSYS)
  58         __have_atfcts = -1;
  59       else
  60 # endif
  61         if (!__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1))
  62           return __xstat64_conv (vers, &kst, st);
  63         else
  64           {
  65             __set_errno (INTERNAL_SYSCALL_ERRNO (result, err));
  66             return -1;
  67           }
  68     }
  69 #endif
  70
  71 #ifndef __ASSUME_ATFCTS
  72   if (flag & ~AT_SYMLINK_NOFOLLOW)
  73     {
  74       __set_errno (EINVAL);
  75       return -1;
  76     }
  77
  78   char *buf = NULL;
  79
  80   if (fd != AT_FDCWD && file[0] != '/')
  81     {
  82       size_t filelen = strlen (file);
  83       static const char procfd[] = "/proc/self/fd/%d/%s";
  84       /* Buffer for the path name we are going to use.  It consists of
  85          - the string /proc/self/fd/
  86          - the file descriptor number
  87          - the file name provided.
  88          The final NUL is included in the sizeof.   A bit of overhead
  89          due to the format elements compensates for possible negative
  90          numbers.  */
  91       size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen;
  92       buf = alloca (buflen);
  93
  94       __snprintf (buf, buflen, procfd, fd, file);
  95       file = buf;
  96     }
  97
  98   if (flag & AT_SYMLINK_NOFOLLOW)
  99     result = INTERNAL_SYSCALL (lstat, err, 2, CHECK_STRING (file),
 100                                __ptrvalue (&kst));
 101   else
 102     result = INTERNAL_SYSCALL (stat, err, 2, CHECK_STRING (file),
 103                                __ptrvalue (&kst));
 104
 105   if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1))
 106     return __xstat64_conv (vers, &kst, st);
 107
 108   __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf);
 109   return -1;
 110 #endif
 111 }
 112 libc_hidden_def (__fxstatat64)