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4973cbe599
* io/Makefile (routines): Add openat and openat64. (tests): Add tst-openat. * io/Versions: Add openat and openat64 for GLIBC_2.4. * sysdeps/generic/openat.c: New file. * sysdeps/generic/openat64.c: New file. * sysdeps/unix/sysv/linux/openat.c: New file. * sysdeps/unix/sysv/linux/openat64.c: New file. * io/tst-openat.c: New file. * sysdeps/unix/sysv/linux/device-nrs.h: Add info for /dev/full.
111 lines
3.0 KiB
C
111 lines
3.0 KiB
C
/* Copyright (C) 2005 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 <stdarg.h>
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#include <stddef.h>
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#include <stdio.h>
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#include <string.h>
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#include <sys/stat.h>
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#include <sysdep-cancel.h>
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#ifndef OPENAT
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# define OPENAT openat
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# define MORE_OFLAGS 0
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#endif
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/* Open FILE with access OFLAG. Interpret relative paths relative to
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the directory associated with FD. If OFLAG includes O_CREAT, a
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third argument is the file protection. */
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int
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OPENAT (fd, file, oflag)
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int fd;
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const char *file;
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int oflag;
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{
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char *buf = NULL;
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if (file[0] != '/')
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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 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 + filelen;
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buf = alloca (buflen);
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__snprintf (buf, buflen, procfd, fd, file);
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file = buf;
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}
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mode_t mode = 0;
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if (oflag & O_CREAT)
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{
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va_list arg;
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va_start (arg, oflag);
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mode = va_arg (arg, mode_t);
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va_end (arg);
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}
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INTERNAL_SYSCALL_DECL (err);
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int res;
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if (SINGLE_THREAD_P)
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res = INTERNAL_SYSCALL (open, err, 3, file, oflag | MORE_OFLAGS, mode);
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else
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{
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int oldtype = LIBC_CANCEL_ASYNC ();
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res = INTERNAL_SYSCALL (open, err, 3, file, oflag | MORE_OFLAGS, mode);
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LIBC_CANCEL_RESET (oldtype);
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}
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if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (res, err), 0))
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{
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int errval = INTERNAL_SYSCALL_ERRNO (res, err);
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if (buf != NULL && errval == ENOTDIR)
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{
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/* This can mean either the file desriptor is invalid or
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/proc is not mounted. */
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struct stat64 st;
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if (__fxstat64 (_STAT_VER, fd, &st) != 0)
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/* errno is already set correctly. */
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goto out;
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/* If /proc is not mounted there is nothing we can do. */
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if (S_ISDIR (st.st_mode)
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&& (__xstat64 (_STAT_VER, "/proc/self/fd", &st) != 0
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|| !S_ISDIR (st.st_mode)))
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errval = ENOSYS;
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}
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__set_errno (errval);
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}
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out:
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return res;
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}
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