/* * Asterisk -- An open source telephony toolkit. * * Copyright (C) 1999 - 2005, Digium, Inc. * * Mark Spencer * * See http://www.asterisk.org for more information about * the Asterisk project. Please do not directly contact * any of the maintainers of this project for assistance; * the project provides a web site, mailing lists and IRC * channels for your use. * * This program is free software, distributed under the terms of * the GNU General Public License Version 2. See the LICENSE file * at the top of the source tree. */ /*! \file * \brief Asterisk module definitions. * * This file contains the definitons for functions Asterisk modules should * provide and some other module related functions. */ #ifndef _ASTERISK_MODULE_H #define _ASTERISK_MODULE_H #if defined(__cplusplus) || defined(c_plusplus) extern "C" { #endif /* Every module should provide these functions */ /*! * \brief Initialize the module. * * This function is called at module load time. Put all code in here * that needs to set up your module's hardware, software, registrations, * etc. * * \return This function should return 0 on success and non-zero on failure. * If the module is not loaded successfully, Asterisk will call its * unload_module() function. */ int load_module(void); /*! * \brief Cleanup all module structures, sockets, etc. * * This is called at exit. Any registrations and memory allocations need to be * unregistered and free'd here. Nothing else will do these for you (until * exit). * * \return Zero on success, or non-zero on error. */ int unload_module(void); /*! * \brief Provides a usecount. * * This function will be called by various parts of asterisk. Basically, all * it has to do is to return a usecount when called. You will need to maintain * your usecount within the module somewhere. The usecount should be how many * channels provided by this module are in use. * * \return The module's usecount. */ int usecount(void); /* How many channels provided by this module are in use? */ /*! \brief Provides a description of the module. * * \return a short description of your module */ char *description(void); /* Description of this module */ /*! * \brief Returns the ASTERISK_GPL_KEY * * This returns the ASTERISK_GPL_KEY, signifiying that you agree to the terms of * the GPL stated in the ASTERISK_GPL_KEY. Your module will not load if it does * not return the EXACT message: * * \code * char *key(void) { * return ASTERISK_GPL_KEY; * } * \endcode * * \return ASTERISK_GPL_KEY */ char *key(void); /* Return the below mentioned key, unmodified */ /*! * \brief Reload stuff. * * This function is where any reload routines take place. Re-read config files, * change signalling, whatever is appropriate on a reload. * * \return The return value is not used. */ int reload(void); /* reload configs */ /*! \brief The text the key() function should return. */ #define ASTERISK_GPL_KEY \ "This paragraph is Copyright (C) 2000, Linux Support Services, Inc. \ In order for your module to load, it must return this key via a function \ called \"key\". Any code which includes this paragraph must be licensed under \ the GNU General Public License version 2 or later (at your option). Linux \ Support Services, Inc. reserves the right to allow other parties to license \ this paragraph under other terms as well." #define AST_MODULE_CONFIG "modules.conf" /*!< \brief Module configuration file */ /*! * \brief Softly unload a module. * * This flag signals ast_unload_resource() to unload a module only if it is not * in use, according to the module's usecount. */ #define AST_FORCE_SOFT 0 /*! * \brief Firmly unload a module. * * This flag signals ast_unload_resource() to attempt to unload a module even * if it is in use. It will attempt to use the module's unload_module * function. */ #define AST_FORCE_FIRM 1 /*! * \brief Unconditionally unload a module. * * This flag signals ast_unload_resource() to first attempt to unload a module * using the module's unload_module function, then if that fails to unload the * module using dlclose. The module will be unloaded even if it is still in * use. Use of this flag is not recommended. */ #define AST_FORCE_HARD 2 /*! * \brief Load a module. * \param resource_name The filename of the module to load. * * This function is run by the PBX to load the modules. It performs * all loading and initilization tasks. Basically, to load a module, just * give it the name of the module and it will do the rest. * * \return Zero on success, -1 on error. */ int ast_load_resource(const char *resource_name); /*! * \brief Unloads a module. * \param resource_name The name of the module to unload. * \param force The force flag. This should be set using one of the AST_FORCE* * flags. * * This function unloads a module. It will only unload modules that are not in * use (usecount not zero), unless #AST_FORCE_FIRM or #AST_FORCE_HARD is * specified. Setting #AST_FORCE_FIRM or #AST_FORCE_HARD will unload the * module regardless of consequences (NOT_RECOMMENDED). * * \return Zero on success, -1 on error. */ int ast_unload_resource(const char *resource_name, int force); /*! * \brief Notify when usecount has been changed. * * This function calulates use counts and notifies anyone trying to keep track * of them. It should be called whenever your module's usecount changes. * * \note The LOCAL_USER macros take care of calling this function for you. */ void ast_update_use_count(void); /*! * \brief Ask for a list of modules, descriptions, and use counts. * \param modentry A callback to an updater function. * \param like * * For each of the modules loaded, modentry will be executed with the resource, * description, and usecount values of each particular module. * * \return the number of modules loaded */ int ast_update_module_list(int (*modentry)(const char *module, const char *description, int usecnt, const char *like), const char *like); /*! * \brief Add a procedure to be run when modules have been updated. * \param updater The function to run when modules have been updated. * * This function adds the given function to a linked list of functions to be * run when the modules are updated. * * \return Zero on success and -1 on failure. */ int ast_loader_register(int (*updater)(void)); /*! * \brief Remove a procedure to be run when modules are updated. * \param updater The updater function to unregister. * * This removes the given function from the updater list. * * \return Zero on success, -1 on failure. */ int ast_loader_unregister(int (*updater)(void)); /*! * \brief Reload asterisk modules. * \param name the name of the module to reload * * This function reloads the specified module, or if no modules are specified, * it will reload all loaded modules. * * \note Modules are reloaded using their reload() functions, not unloading * them and loading them again. * * \return Zero if the specified module was not found, 1 if the module was * found but cannot be reloaded, -1 if a reload operation is already in * progress, and 2 if the specfied module was found and reloaded. */ int ast_module_reload(const char *name); /*! * \brief Match modules names for the Asterisk cli. * \param line Unused by this function, but this should be the line we are * matching. * \param word The partial name to match. * \param pos The position the word we are completing is in. * \param state The possible match to return. * \param rpos The position we should be matching. This should be the same as * pos. * \param needsreload This should be 1 if we need to reload this module and 0 * otherwise. This function will only return modules that are reloadble * if this is 1. * * \return A possible completion of the partial match, or NULL if no matches * were found. */ char *ast_module_helper(char *line, char *word, int pos, int state, int rpos, int needsreload); /*! * \brief Register a function to be executed before Asterisk exits. * \param func The callback function to use. * * \return Zero on success, -1 on error. */ int ast_register_atexit(void (*func)(void)); /*! * \brief Unregister a function registered with ast_register_atexit(). * \param func The callback function to unregister. */ void ast_unregister_atexit(void (*func)(void)); /* Local user routines keep track of which channels are using a given module resource. They can help make removing modules safer, particularly if they're in use at the time they have been requested to be removed */ /*! * \brief Standard localuser struct definition. * * This macro defines a localuser struct. The channel.h file must be included * to use this macro because it refrences ast_channel. */ #define STANDARD_LOCAL_USER struct localuser { \ struct ast_channel *chan; \ struct localuser *next; \ } /*! * \brief The localuser declaration. * * This macro should be used in combination with #STANDARD_LOCAL_USER. It * creates a localuser mutex and several other variables used for keeping the * use count. * * Sample Usage: * \code * STANDARD_LOCAL_USER; * LOCAL_USER_DECL; * \endcode */ #define LOCAL_USER_DECL AST_MUTEX_DEFINE_STATIC(localuser_lock); \ static struct localuser *localusers = NULL; \ static int localusecnt = 0; #define STANDARD_INCREMENT_USECOUNT \ ast_mutex_lock(&localuser_lock); \ localusecnt++; \ ast_mutex_unlock(&localuser_lock); \ ast_update_use_count(); #define STANDARD_DECREMENT_USECOUNT \ ast_mutex_lock(&localuser_lock); \ localusecnt--; \ ast_mutex_unlock(&localuser_lock); \ ast_update_use_count(); /*! * \brief Add a localuser. * \param u a pointer to a localuser struct * * This macro adds a localuser to the list of users and increments the * usecount. It expects a variable named \p chan of type \p ast_channel in the * current scope. * * \note This function dynamically allocates memory. If this operation fails * it will cause your function to return -1 to the caller. */ #define LOCAL_USER_ADD(u) { \ \ if (!(u=calloc(1,sizeof(*u)))) { \ ast_log(LOG_WARNING, "Out of memory\n"); \ return -1; \ } \ ast_mutex_lock(&localuser_lock); \ u->chan = chan; \ u->next = localusers; \ localusers = u; \ localusecnt++; \ ast_mutex_unlock(&localuser_lock); \ ast_update_use_count(); \ } #define LOCAL_USER_ACF_ADD(u) { \ \ if (!(u=calloc(1,sizeof(*u)))) { \ ast_log(LOG_WARNING, "Out of memory\n"); \ return ""; \ } \ ast_mutex_lock(&localuser_lock); \ u->chan = chan; \ u->next = localusers; \ localusers = u; \ localusecnt++; \ ast_mutex_unlock(&localuser_lock); \ ast_update_use_count(); \ } /*! * \brief Remove a localuser. * \param u the user to add, should be of type struct localuser * * This macro removes a localuser from the list of users and decrements the * usecount. */ #define LOCAL_USER_REMOVE(u) { \ struct localuser *uc, *ul = NULL; \ ast_mutex_lock(&localuser_lock); \ uc = localusers; \ while (uc) { \ if (uc == u) { \ if (ul) \ ul->next = uc->next; \ else \ localusers = uc->next; \ break; \ } \ ul = uc; \ uc = uc->next; \ }\ free(u); \ localusecnt--; \ ast_mutex_unlock(&localuser_lock); \ ast_update_use_count(); \ } /*! * \brief Hangup all localusers. * * This macro hangs up on all current localusers and sets the usecount to zero * when finished. */ #define STANDARD_HANGUP_LOCALUSERS { \ struct localuser *u, *ul; \ ast_mutex_lock(&localuser_lock); \ u = localusers; \ while(u) { \ ast_softhangup(u->chan, AST_SOFTHANGUP_APPUNLOAD); \ ul = u; \ u = u->next; \ free(ul); \ } \ localusecnt=0; \ ast_mutex_unlock(&localuser_lock); \ ast_update_use_count(); \ } /*! * \brief Set the specfied integer to the current usecount. * \param res the integer variable to set. * * This macro sets the specfied integer variable to the local usecount. * * Sample Usage: * \code * int usecount(void) * { * int res; * STANDARD_USECOUNT(res); * return res; * } * \endcode */ #define STANDARD_USECOUNT(res) { \ res = localusecnt; \ } #if defined(__cplusplus) || defined(c_plusplus) } #endif #endif /* _ASTERISK_MODULE_H */