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Edit File: util_mutex.h
/* 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. */ /** * @file util_mutex.h * @brief Apache Mutex support library * * @defgroup APACHE_CORE_MUTEX Mutex Library * @ingroup APACHE_CORE * @{ */ #ifndef UTIL_MUTEX_H #define UTIL_MUTEX_H #include "httpd.h" #include "http_config.h" #include "apr_global_mutex.h" #if APR_HAS_FLOCK_SERIALIZE # define AP_LIST_FLOCK_SERIALIZE ", 'flock:/path/to/file'" #else # define AP_LIST_FLOCK_SERIALIZE #endif #if APR_HAS_FCNTL_SERIALIZE # define AP_LIST_FCNTL_SERIALIZE ", 'fcntl:/path/to/file'" #else # define AP_LIST_FCNTL_SERIALIZE #endif #if APR_HAS_SYSVSEM_SERIALIZE # define AP_LIST_SYSVSEM_SERIALIZE ", 'sysvsem'" #else # define AP_LIST_SYSVSEM_SERIALIZE #endif #if APR_HAS_POSIXSEM_SERIALIZE # define AP_LIST_POSIXSEM_SERIALIZE ", 'posixsem'" #else # define AP_LIST_POSIXSEM_SERIALIZE #endif #if APR_HAS_PROC_PTHREAD_SERIALIZE # define AP_LIST_PTHREAD_SERIALIZE ", 'pthread'" #else # define AP_LIST_PTHREAD_SERIALIZE #endif #if APR_HAS_FLOCK_SERIALIZE || APR_HAS_FCNTL_SERIALIZE # define AP_LIST_FILE_SERIALIZE ", 'file:/path/to/file'" #else # define AP_LIST_FILE_SERIALIZE #endif #if APR_HAS_SYSVSEM_SERIALIZE || APR_HAS_POSIXSEM_SERIALIZE # define AP_LIST_SEM_SERIALIZE ", 'sem'" #else # define AP_LIST_SEM_SERIALIZE #endif #define AP_ALL_AVAILABLE_MUTEXES_STRING \ "Mutex mechanisms are: 'none', 'default'" \ AP_LIST_FLOCK_SERIALIZE AP_LIST_FCNTL_SERIALIZE \ AP_LIST_FILE_SERIALIZE AP_LIST_PTHREAD_SERIALIZE \ AP_LIST_SYSVSEM_SERIALIZE AP_LIST_POSIXSEM_SERIALIZE \ AP_LIST_SEM_SERIALIZE #define AP_AVAILABLE_MUTEXES_STRING \ "Mutex mechanisms are: 'default'" \ AP_LIST_FLOCK_SERIALIZE AP_LIST_FCNTL_SERIALIZE \ AP_LIST_FILE_SERIALIZE AP_LIST_PTHREAD_SERIALIZE \ AP_LIST_SYSVSEM_SERIALIZE AP_LIST_POSIXSEM_SERIALIZE \ AP_LIST_SEM_SERIALIZE #ifdef __cplusplus extern "C" { #endif /** * Get Mutex config data and parse it * @param arg The mutex config string * @param pool The allocation pool * @param mutexmech The APR mutex locking mechanism * @param mutexfile The lockfile to use as required * @return APR status code * @fn apr_status_t ap_parse_mutex(const char *arg, apr_pool_t *pool, apr_lockmech_e *mutexmech, const char **mutexfile) */ AP_DECLARE(apr_status_t) ap_parse_mutex(const char *arg, apr_pool_t *pool, apr_lockmech_e *mutexmech, const char **mutexfile); /* private function to process the Mutex directive */ AP_DECLARE_NONSTD(const char *) ap_set_mutex(cmd_parms *cmd, void *dummy, const char *arg); /* private function to initialize Mutex infrastructure */ AP_DECLARE_NONSTD(void) ap_mutex_init(apr_pool_t *p); /** * option flags for ap_mutex_register(), ap_global_mutex_create(), and * ap_proc_mutex_create() */ #define AP_MUTEX_ALLOW_NONE 1 /* allow "none" as mutex implementation; * respected only on ap_mutex_register() */ #define AP_MUTEX_DEFAULT_NONE 2 /* default to "none" for this mutex; * respected only on ap_mutex_register() */ /** * Register a module's mutex type with core to allow configuration * with the Mutex directive. This must be called in the pre_config * hook; otherwise, configuration directives referencing this mutex * type will be rejected. * * The default_dir and default_mech parameters allow a module to set * defaults for the lock file directory and mechanism. These could * be based on compile-time settings. These aren't required except * in special circumstances. * * The order of precedence for the choice of mechanism and lock file * directory is: * * 1. Mutex directive specifically for this mutex * e.g., Mutex mpm-default flock:/tmp/mpmlocks * 2. Mutex directive for global default * e.g., Mutex default flock:/tmp/httpdlocks * 3. Defaults for this mutex provided on the ap_mutex_register() * 4. Built-in defaults for all mutexes, which are * APR_LOCK_DEFAULT and DEFAULT_REL_RUNTIMEDIR. * * @param pconf The pconf pool * @param type The type name of the mutex, used as the basename of the * file associated with the mutex, if any. This must be unique among * all mutex types (mutex creation accommodates multi-instance mutex * types); mod_foo might have mutex types "foo-pipe" and "foo-shm" * @param default_dir Default dir for any lock file required for this * lock, to override built-in defaults; should be NULL for most * modules, to respect built-in defaults * @param default_mech Default mechanism for this lock, to override * built-in defaults; should be APR_LOCK_DEFAULT for most modules, to * respect built-in defaults * or NULL if there are no defaults for this mutex. * @param options combination of AP_MUTEX_* constants, or 0 for defaults */ AP_DECLARE(apr_status_t) ap_mutex_register(apr_pool_t *pconf, const char *type, const char *default_dir, apr_lockmech_e default_mech, apr_int32_t options); /** * Create an APR global mutex that has been registered previously with * ap_mutex_register(). Mutex files, permissions, and error logging will * be handled internally. * @param mutex The memory address where the newly created mutex will be * stored. If this mutex is disabled, mutex will be set to NULL on * output. (That is allowed only if the AP_MUTEX_ALLOW_NONE flag is * passed to ap_mutex_register().) * @param name The generated filename of the created mutex, or NULL if * no file was created. Pass NULL if this result is not needed. * @param type The type name of the mutex, matching the type name passed * to ap_mutex_register(). * @param instance_id A unique string to be used in the lock filename IFF * this mutex type is multi-instance, NULL otherwise. * @param server server_rec of main server * @param pool pool lifetime of the mutex * @param options combination of AP_MUTEX_* constants, or 0 for defaults * (currently none are defined for this function) */ AP_DECLARE(apr_status_t) ap_global_mutex_create(apr_global_mutex_t **mutex, const char **name, const char *type, const char *instance_id, server_rec *server, apr_pool_t *pool, apr_int32_t options); /** * Create an APR proc mutex that has been registered previously with * ap_mutex_register(). Mutex files, permissions, and error logging will * be handled internally. * @param mutex The memory address where the newly created mutex will be * stored. If this mutex is disabled, mutex will be set to NULL on * output. (That is allowed only if the AP_MUTEX_ALLOW_NONE flag is * passed to ap_mutex_register().) * @param name The generated filename of the created mutex, or NULL if * no file was created. Pass NULL if this result is not needed. * @param type The type name of the mutex, matching the type name passed * to ap_mutex_register(). * @param instance_id A unique string to be used in the lock filename IFF * this mutex type is multi-instance, NULL otherwise. * @param server server_rec of main server * @param pool pool lifetime of the mutex * @param options combination of AP_MUTEX_* constants, or 0 for defaults * (currently none are defined for this function) */ AP_DECLARE(apr_status_t) ap_proc_mutex_create(apr_proc_mutex_t **mutex, const char **name, const char *type, const char *instance_id, server_rec *server, apr_pool_t *pool, apr_int32_t options); AP_CORE_DECLARE(void) ap_dump_mutexes(apr_pool_t *p, server_rec *s, apr_file_t *out); #ifdef __cplusplus } #endif #endif /* UTIL_MUTEX_H */ /** @} */