diff options
Diffstat (limited to 'io/lockf64.c')
| -rw-r--r-- | io/lockf64.c | 71 |
1 files changed, 25 insertions, 46 deletions
diff --git a/io/lockf64.c b/io/lockf64.c index 334b8d3180..fcbca33ae3 100644 --- a/io/lockf64.c +++ b/io/lockf64.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1994-2018 Free Software Foundation, Inc. +/* Copyright (C) 1994-2019 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 @@ -13,71 +13,50 @@ You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ + <https://www.gnu.org/licenses/>. */ -#include <sys/types.h> #include <unistd.h> #include <fcntl.h> #include <errno.h> -#include <string.h> - -/* lockf.c defines lockf64 as an alias if __OFF_T_MATCHES_OFF64_T. */ -#ifndef __OFF_T_MATCHES_OFF64_T /* lockf is a simplified interface to fcntl's locking facilities. */ - int -lockf64 (int fd, int cmd, off64_t len64) +__lockf64 (int fd, int cmd, off64_t len64) { - struct flock fl; - off_t len = (off_t) len64; - - if (len64 != (off64_t) len) - { - /* We can't represent the length. */ - __set_errno (EOVERFLOW); - return -1; - } - - memset ((char *) &fl, '\0', sizeof (fl)); - /* lockf is always relative to the current file position. */ - fl.l_whence = SEEK_CUR; - fl.l_start = 0; - fl.l_len = len; - + struct flock64 fl64 = { + .l_type = F_WRLCK, + .l_whence = SEEK_CUR, + .l_len = len64, + }; + + /* lockf() is a cancellation point but so is fcntl() if F_SETLKW is + used. Therefore we don't have to care about cancellation here, + the fcntl() function will take care of it. */ switch (cmd) { case F_TEST: /* Test the lock: return 0 if FD is unlocked or locked by this process; return -1, set errno to EACCES, if another process holds the lock. */ - fl.l_type = F_RDLCK; - if (__fcntl (fd, F_GETLK, &fl) < 0) + fl64.l_type = F_RDLCK; + if (__fcntl (fd, F_GETLK64, &fl64) < 0) return -1; - if (fl.l_type == F_UNLCK || fl.l_pid == __getpid ()) - return 0; + if (fl64.l_type == F_UNLCK || fl64.l_pid == __getpid ()) + return 0; __set_errno (EACCES); return -1; - case F_ULOCK: - fl.l_type = F_UNLCK; - cmd = F_SETLK; - break; + fl64.l_type = F_UNLCK; + return __fcntl64 (fd, F_SETLK64, &fl64); case F_LOCK: - fl.l_type = F_WRLCK; - cmd = F_SETLKW; - break; + return __fcntl64 (fd, F_SETLKW64, &fl64); case F_TLOCK: - fl.l_type = F_WRLCK; - cmd = F_SETLK; - break; - - default: - __set_errno (EINVAL); - return -1; + return __fcntl64 (fd, F_SETLK64, &fl64); } - - return __fcntl (fd, cmd, &fl); + __set_errno (EINVAL); + return -1; } - +weak_alias (__lockf64, lockf64) +#ifdef __OFF_T_MATCHES_OFF64_T +weak_alias (lockf64, lockf) #endif |