[BACK]Return to lockf.c CVS log [TXT][DIR] Up to [cvs.NetBSD.org] / src / lib / libc / gen

Annotation of src/lib/libc/gen/lockf.c, Revision 1.2.38.1

1.2.38.1! yamt        1: /*     $NetBSD: lockf.c,v 1.2 2000/01/22 22:19:11 mycroft Exp $        */
1.1       kleink      2:
                      3: /*-
                      4:  * Copyright (c) 1997 The NetBSD Foundation, Inc.
                      5:  * All rights reserved.
                      6:  *
                      7:  * This code is derived from software contributed to The NetBSD Foundation
                      8:  * by Klaus Klein.
                      9:  *
                     10:  * Redistribution and use in source and binary forms, with or without
                     11:  * modification, are permitted provided that the following conditions
                     12:  * are met:
                     13:  * 1. Redistributions of source code must retain the above copyright
                     14:  *    notice, this list of conditions and the following disclaimer.
                     15:  * 2. Redistributions in binary form must reproduce the above copyright
                     16:  *    notice, this list of conditions and the following disclaimer in the
                     17:  *    documentation and/or other materials provided with the distribution.
                     18:  *
                     19:  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
                     20:  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
                     21:  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
                     22:  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
                     23:  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
                     24:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
                     25:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
                     26:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
                     27:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
                     28:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
                     29:  * POSSIBILITY OF SUCH DAMAGE.
                     30:  */
                     31:
                     32: #include <sys/cdefs.h>
                     33: #if defined(LIBC_SCCS) && !defined(lint)
1.2.38.1! yamt       34: __RCSID("$NetBSD: lockf.c,v 1.2 2000/01/22 22:19:11 mycroft Exp $");
1.1       kleink     35: #endif
                     36:
                     37: #include "namespace.h"
                     38: #include <errno.h>
                     39: #include <fcntl.h>
                     40: #include <unistd.h>
                     41:
                     42: #ifdef __weak_alias
1.2       mycroft    43: __weak_alias(lockf,_lockf)
1.1       kleink     44: #endif
                     45:
                     46:
                     47: int
                     48: lockf(filedes, function, size)
                     49:        int filedes;
                     50:        int function;
                     51:        off_t size;
                     52: {
                     53:        struct flock fl;
                     54:        int cmd;
                     55:
                     56:        fl.l_start = 0;
                     57:        fl.l_len = size;
                     58:        fl.l_whence = SEEK_CUR;
                     59:
                     60:        switch (function) {
                     61:        case F_ULOCK:
                     62:                cmd = F_SETLK;
                     63:                fl.l_type = F_UNLCK;
                     64:                break;
                     65:        case F_LOCK:
                     66:                cmd = F_SETLKW;
                     67:                fl.l_type = F_WRLCK;
                     68:                break;
                     69:        case F_TLOCK:
                     70:                cmd = F_SETLK;
                     71:                fl.l_type = F_WRLCK;
                     72:                break;
                     73:        case F_TEST:
                     74:                fl.l_type = F_WRLCK;
                     75:                if (fcntl(filedes, F_GETLK, &fl) == -1)
                     76:                        return (-1);
                     77:                if (fl.l_type == F_UNLCK || fl.l_pid == getpid())
                     78:                        return (0);
                     79:                errno = EAGAIN;
                     80:                return (-1);
                     81:                /* NOTREACHED */
                     82:        default:
                     83:                errno = EINVAL;
                     84:                return (-1);
                     85:                /* NOTREACHED */
                     86:        }
                     87:
                     88:        return (fcntl(filedes, cmd, &fl));
                     89: }

CVSweb <webmaster@jp.NetBSD.org>