/**************************************************************************** * sched/pthread/pthread_mutexinit.c * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include "pthread/pthread.h" /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: pthread_mutex_init * * Description: * Create a mutex * * Input Parameters: * None * * Returned Value: * None * * Assumptions: * ****************************************************************************/ int pthread_mutex_init(FAR pthread_mutex_t *mutex, FAR const pthread_mutexattr_t *attr) { int pshared = 0; #ifdef CONFIG_PTHREAD_MUTEX_TYPES uint8_t type = PTHREAD_MUTEX_DEFAULT; #endif #ifdef CONFIG_PRIORITY_INHERITANCE uint8_t proto = PTHREAD_PRIO_INHERIT; #endif #ifndef CONFIG_PTHREAD_MUTEX_UNSAFE #ifdef CONFIG_PTHREAD_MUTEX_DEFAULT_UNSAFE uint8_t robust = PTHREAD_MUTEX_STALLED; #else uint8_t robust = PTHREAD_MUTEX_ROBUST; #endif #endif int ret = OK; int status; sinfo("mutex=0x%p attr=0x%p\n", mutex, attr); if (!mutex) { ret = EINVAL; } else { /* Were attributes specified? If so, use them */ if (attr) { pshared = attr->pshared; #ifdef CONFIG_PRIORITY_INHERITANCE proto = attr->proto; #endif #ifdef CONFIG_PTHREAD_MUTEX_TYPES type = attr->type; #endif #ifdef CONFIG_PTHREAD_MUTEX_BOTH robust = attr->robust; #endif } /* Indicate that the semaphore is not held by any thread. */ mutex->pid = -1; /* Initialize the mutex like a semaphore with initial count = 1 */ status = nxsem_init((FAR sem_t *)&mutex->sem, pshared, 1); if (status < 0) { ret = -ret; } #ifdef CONFIG_PRIORITY_INHERITANCE /* Initialize the semaphore protocol */ status = nxsem_set_protocol((FAR sem_t *)&mutex->sem, proto); if (status < 0) { ret = -status; } #endif #ifndef CONFIG_PTHREAD_MUTEX_UNSAFE /* Initial internal fields of the mutex */ mutex->flink = NULL; mutex->flags = (robust == PTHREAD_MUTEX_ROBUST ? _PTHREAD_MFLAGS_ROBUST : 0); #endif #ifdef CONFIG_PTHREAD_MUTEX_TYPES /* Set up attributes unique to the mutex type */ mutex->type = type; mutex->nlocks = 0; #endif } sinfo("Returning %d\n", ret); return ret; }