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e442e40de5
With internal fcntl64 internal (commit 06ab719d), it is possible to
consolidate lockf implementation by using the LFS fcntl interface
instead of using arch and system-specific implementations.
For Linux, the i386 implementation is used as generic implementation
by replacing the direct syscall with fcntl64 call. The LFS symbol
alias for default LFS ABI (__OFF_T_MATCHES_OFF64_T) is used to avoid
the duplicate symbol (instead of overriding the implementation with an
empty file).
For Hurd lockf64 semantic is changed: previous generic lockf64
implementation returned EOVERFLOW if LEN input is larger than 32-bit
off_t. However, Hurd fcntl64 implementation for F_GETLK64, F_SETLK64,
and F_SETLKW64 do accept off64_t inputs (__f_setlk accepts only off64_t
inputs).
Checked on i686-linux-gnu and x86_64-linux-gnu along with a i686-gnu
build.
* io/Makefile (tests): Add tst-lockf.
* io/lockf.c (lockf): Use __fcntl and only define for
!__OFF_T_MATCHES_OFF64_T.
* io/lockf64.c (__lockf64): Call __fcntl64 and alias to lockf for
__OFF_T_MATCHES_OFF64_T case.
* io/tst-lockf.c: New file.
* sysdeps/unix/sysv/linux/i386/lockf64.c: Remove file.
* sysdeps/unix/sysv/linux/arm/lockf64.c: Likewise.
* sysdeps/unix/sysv/linux/m68k/lockf64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/lockf64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/lockf64.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/lockf64.c: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/lockf64.c: Likewise.
* sysdeps/unix/sysv/linux/sh/lockf64.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/lockf64.c: Likewise.
62 lines
1.9 KiB
C
62 lines
1.9 KiB
C
/* Copyright (C) 1994-2019 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, see
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<http://www.gnu.org/licenses/>. */
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#ifndef __OFF_T_MATCHES_OFF64_T
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#include <unistd.h>
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#include <fcntl.h>
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#include <errno.h>
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/* lockf is a simplified interface to fcntl's locking facilities. */
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int
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lockf (int fd, int cmd, off_t len)
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{
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/* lockf is always relative to the current file position. */
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struct flock fl = {
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.l_type = F_WRLCK,
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.l_whence = SEEK_CUR,
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.l_len = len
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};
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/* lockf() is a cancellation point but so is fcntl() if F_SETLKW is
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used. Therefore we don't have to care about cancellation here,
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the fcntl() function will take care of it. */
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switch (cmd)
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{
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case F_TEST:
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/* Test the lock: return 0 if FD is unlocked or locked by this process;
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return -1, set errno to EACCES, if another process holds the lock. */
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fl.l_type = F_RDLCK;
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if (__fcntl (fd, F_GETLK, &fl) < 0)
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return -1;
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if (fl.l_type == F_UNLCK || fl.l_pid == __getpid ())
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return 0;
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__set_errno (EACCES);
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return -1;
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case F_ULOCK:
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fl.l_type = F_UNLCK;
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return __fcntl (fd, F_SETLK, &fl);
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case F_LOCK:
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return __fcntl (fd, F_SETLKW, &fl);
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case F_TLOCK:
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return __fcntl (fd, F_SETLK, &fl);
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}
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__set_errno (EINVAL);
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return -1;
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}
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#endif
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