00001 /* 00002 * Copyright (C) 2008 by EmbeddedIT, 00003 * Ole Reinhardt <ole.reinhardt@embedded-it.de> All rights reserved. 00004 * 00005 * Redistribution and use in source and binary forms, with or without 00006 * modification, are permitted provided that the following conditions 00007 * are met: 00008 * 00009 * 1. Redistributions of source code must retain the above copyright 00010 * notice, this list of conditions and the following disclaimer. 00011 * 2. Redistributions in binary form must reproduce the above copyright 00012 * notice, this list of conditions and the following disclaimer in the 00013 * documentation and/or other materials provided with the distribution. 00014 * 3. Neither the name of the copyright holders nor the names of 00015 * contributors may be used to endorse or promote products derived 00016 * from this software without specific prior written permission. 00017 * 00018 * THIS SOFTWARE IS PROVIDED BY EMBEDDED IT AND CONTRIBUTORS 00019 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 00020 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 00021 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL EMBEDDED IT 00022 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 00023 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 00024 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 00025 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 00026 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 00027 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 00028 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00029 * 00030 * For additional information see http://www.ethernut.de/ 00031 * 00032 */ 00033 00034 /* 00035 * $Log: condition.c,v $ 00036 * Revision 1.2 2008/04/29 01:51:35 thiagocorrea 00037 * Compile fix 00038 * 00039 * Revision 1.1 2008/04/21 22:24:53 olereinhardt 00040 * Implemented condition variables to use with NutOS as an application candy 00041 * 00042 */ 00043 00044 #include <sys/heap.h> 00045 #include <sys/event.h> 00046 #include <sys/atom.h> 00047 #include <sys/timer.h> 00048 #include <sys/thread.h> 00049 #include <sys/condition.h> 00050 #include <stddef.h> /* NULL definition */ 00051 00056 00063 CONDITION NutConditionInit(void) 00064 { 00065 CONDITION cond; 00066 cond = NutHeapAlloc(sizeof(cond)); 00067 if (cond == NULL) return NULL; 00068 NutMutexInit(&cond->mutex); 00069 return cond; 00070 } 00071 00082 void NutConditionLock(CONDITION cond) 00083 { 00084 if (cond == NULL) return; 00085 NutMutexLock(&cond->mutex); 00086 } 00087 00098 void NutConditionUnlock(CONDITION cond) 00099 { 00100 if (cond == NULL) return; 00101 NutMutexUnlock(&cond->mutex); 00102 } 00103 00127 int NutConditionWait(CONDITION cond) 00128 { 00129 if (cond == NULL) return -1; 00130 NutMutexUnlock(&cond->mutex); 00131 NutEventWait(cond->event, NUT_WAIT_INFINITE); 00132 NutMutexLock(&cond->mutex); 00133 return 0; 00134 } 00135 00164 int NutConditionTimedWait(CONDITION cond, u_long abs_ms) 00165 { 00166 u_long ms; 00167 00168 if (cond == NULL) return -1; 00169 ms = abs_ms - NutGetMillis(); 00170 if (ms > 0x7FFFFFFF) return -1; 00171 00172 NutMutexUnlock(&cond->mutex); 00173 NutEventWait(&cond->event, ms); 00174 NutMutexLock(&cond->mutex); 00175 return 0; 00176 } 00177 00190 int NutConditionSignal(CONDITION cond) 00191 { 00192 if (cond == NULL) return -1; 00193 return NutEventPost(&cond->event); 00194 } 00195 00208 int NutConditionBroadcast(CONDITION cond) 00209 { 00210 if (cond == NULL) return -1; 00211 return NutEventBroadcast(&cond->event); 00212 } 00213 00219 void NutConditionFree(CONDITION *cond) 00220 { 00221 NutMutexDestroy(&(*cond)->mutex); 00222 NutHeapFree(cond); 00223 cond = NULL; 00224 } 00225