1251875Speter/* Licensed to the Apache Software Foundation (ASF) under one or more 2251875Speter * contributor license agreements. See the NOTICE file distributed with 3251875Speter * this work for additional information regarding copyright ownership. 4251875Speter * The ASF licenses this file to You under the Apache License, Version 2.0 5251875Speter * (the "License"); you may not use this file except in compliance with 6251875Speter * the License. You may obtain a copy of the License at 7251875Speter * 8251875Speter * http://www.apache.org/licenses/LICENSE-2.0 9251875Speter * 10251875Speter * Unless required by applicable law or agreed to in writing, software 11251875Speter * distributed under the License is distributed on an "AS IS" BASIS, 12251875Speter * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13251875Speter * See the License for the specific language governing permissions and 14251875Speter * limitations under the License. 15251875Speter */ 16251875Speter 17251875Speter#include "apr_arch_file_io.h" 18251875Speter 19251875Speter#if APR_HAVE_FCNTL_H 20251875Speter#include <fcntl.h> 21251875Speter#endif 22251875Speter#ifdef HAVE_SYS_FILE_H 23251875Speter#include <sys/file.h> 24251875Speter#endif 25251875Speter 26251875SpeterAPR_DECLARE(apr_status_t) apr_file_lock(apr_file_t *thefile, int type) 27251875Speter{ 28251875Speter int rc; 29251875Speter 30251875Speter#if defined(HAVE_FCNTL_H) 31251875Speter { 32251875Speter struct flock l = { 0 }; 33251875Speter int fc; 34251875Speter 35251875Speter l.l_whence = SEEK_SET; /* lock from current point */ 36251875Speter l.l_start = 0; /* begin lock at this offset */ 37251875Speter l.l_len = 0; /* lock to end of file */ 38251875Speter if ((type & APR_FLOCK_TYPEMASK) == APR_FLOCK_SHARED) 39251875Speter l.l_type = F_RDLCK; 40251875Speter else 41251875Speter l.l_type = F_WRLCK; 42251875Speter 43251875Speter fc = (type & APR_FLOCK_NONBLOCK) ? F_SETLK : F_SETLKW; 44251875Speter 45251875Speter /* keep trying if fcntl() gets interrupted (by a signal) */ 46251875Speter while ((rc = fcntl(thefile->filedes, fc, &l)) < 0 && errno == EINTR) 47251875Speter continue; 48251875Speter 49251875Speter if (rc == -1) { 50251875Speter /* on some Unix boxes (e.g., Tru64), we get EACCES instead 51251875Speter * of EAGAIN; we don't want APR_STATUS_IS_EAGAIN() matching EACCES 52251875Speter * since that breaks other things, so fix up the retcode here 53251875Speter */ 54251875Speter if (errno == EACCES) { 55251875Speter return EAGAIN; 56251875Speter } 57251875Speter return errno; 58251875Speter } 59251875Speter } 60251875Speter#elif defined(HAVE_SYS_FILE_H) 61251875Speter { 62251875Speter int ltype; 63251875Speter 64251875Speter if ((type & APR_FLOCK_TYPEMASK) == APR_FLOCK_SHARED) 65251875Speter ltype = LOCK_SH; 66251875Speter else 67251875Speter ltype = LOCK_EX; 68251875Speter if ((type & APR_FLOCK_NONBLOCK) != 0) 69251875Speter ltype |= LOCK_NB; 70251875Speter 71251875Speter /* keep trying if flock() gets interrupted (by a signal) */ 72251875Speter while ((rc = flock(thefile->filedes, ltype)) < 0 && errno == EINTR) 73251875Speter continue; 74251875Speter 75251875Speter if (rc == -1) 76251875Speter return errno; 77251875Speter } 78251875Speter#else 79251875Speter#error No file locking mechanism is available. 80251875Speter#endif 81251875Speter 82251875Speter return APR_SUCCESS; 83251875Speter} 84251875Speter 85251875SpeterAPR_DECLARE(apr_status_t) apr_file_unlock(apr_file_t *thefile) 86251875Speter{ 87251875Speter int rc; 88251875Speter 89251875Speter#if defined(HAVE_FCNTL_H) 90251875Speter { 91251875Speter struct flock l = { 0 }; 92251875Speter 93251875Speter l.l_whence = SEEK_SET; /* lock from current point */ 94251875Speter l.l_start = 0; /* begin lock at this offset */ 95251875Speter l.l_len = 0; /* lock to end of file */ 96251875Speter l.l_type = F_UNLCK; 97251875Speter 98251875Speter /* keep trying if fcntl() gets interrupted (by a signal) */ 99251875Speter while ((rc = fcntl(thefile->filedes, F_SETLKW, &l)) < 0 100251875Speter && errno == EINTR) 101251875Speter continue; 102251875Speter 103251875Speter if (rc == -1) 104251875Speter return errno; 105251875Speter } 106251875Speter#elif defined(HAVE_SYS_FILE_H) 107251875Speter { 108251875Speter /* keep trying if flock() gets interrupted (by a signal) */ 109251875Speter while ((rc = flock(thefile->filedes, LOCK_UN)) < 0 && errno == EINTR) 110251875Speter continue; 111251875Speter 112251875Speter if (rc == -1) 113251875Speter return errno; 114251875Speter } 115251875Speter#else 116251875Speter#error No file locking mechanism is available. 117251875Speter#endif 118251875Speter 119251875Speter return APR_SUCCESS; 120251875Speter} 121