diff options
| -rw-r--r-- | codecs/codec_a_mu.c | 2 | ||||
| -rw-r--r-- | codecs/codec_adpcm.c | 2 | ||||
| -rw-r--r-- | codecs/codec_alaw.c | 2 | ||||
| -rw-r--r-- | codecs/codec_g723_1.c | 2 | ||||
| -rw-r--r-- | codecs/codec_g726.c | 2 | ||||
| -rw-r--r-- | codecs/codec_gsm.c | 2 | ||||
| -rw-r--r-- | codecs/codec_ilbc.c | 2 | ||||
| -rw-r--r-- | codecs/codec_lpc10.c | 2 | ||||
| -rw-r--r-- | codecs/codec_speex.c | 2 | ||||
| -rw-r--r-- | codecs/codec_ulaw.c | 2 | ||||
| -rw-r--r-- | include/asterisk/module.h | 272 | ||||
| -rw-r--r-- | loader.c | 501 | ||||
| -rw-r--r-- | res/res_smdi.c | 13 |
13 files changed, 661 insertions, 145 deletions
diff --git a/codecs/codec_a_mu.c b/codecs/codec_a_mu.c index c21b26c95..f03612b13 100644 --- a/codecs/codec_a_mu.c +++ b/codecs/codec_a_mu.c @@ -316,7 +316,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/codecs/codec_adpcm.c b/codecs/codec_adpcm.c index 19fd33c31..19970a501 100644 --- a/codecs/codec_adpcm.c +++ b/codecs/codec_adpcm.c @@ -616,7 +616,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/codecs/codec_alaw.c b/codecs/codec_alaw.c index a56e42a02..480b92c2a 100644 --- a/codecs/codec_alaw.c +++ b/codecs/codec_alaw.c @@ -416,7 +416,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/codecs/codec_g723_1.c b/codecs/codec_g723_1.c index fc508ff26..c226bb0c2 100644 --- a/codecs/codec_g723_1.c +++ b/codecs/codec_g723_1.c @@ -407,7 +407,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/codecs/codec_g726.c b/codecs/codec_g726.c index 2a39e90a3..6a33d8519 100644 --- a/codecs/codec_g726.c +++ b/codecs/codec_g726.c @@ -1078,7 +1078,7 @@ int usecount (void) { int res; - STANDARD_USECOUNT (res); + OLD_STANDARD_USECOUNT (res); return res; } diff --git a/codecs/codec_gsm.c b/codecs/codec_gsm.c index ee28e852d..59ce77fab 100644 --- a/codecs/codec_gsm.c +++ b/codecs/codec_gsm.c @@ -347,7 +347,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/codecs/codec_ilbc.c b/codecs/codec_ilbc.c index 8c928fbcd..fb042cfa5 100644 --- a/codecs/codec_ilbc.c +++ b/codecs/codec_ilbc.c @@ -307,7 +307,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/codecs/codec_lpc10.c b/codecs/codec_lpc10.c index fe37383a7..f9157cdc8 100644 --- a/codecs/codec_lpc10.c +++ b/codecs/codec_lpc10.c @@ -420,7 +420,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/codecs/codec_speex.c b/codecs/codec_speex.c index 7d7871e21..fc9b22bfb 100644 --- a/codecs/codec_speex.c +++ b/codecs/codec_speex.c @@ -602,7 +602,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/codecs/codec_ulaw.c b/codecs/codec_ulaw.c index 38332019c..4f38a024e 100644 --- a/codecs/codec_ulaw.c +++ b/codecs/codec_ulaw.c @@ -418,7 +418,7 @@ char *description(void) int usecount(void) { int res; - STANDARD_USECOUNT(res); + OLD_STANDARD_USECOUNT(res); return res; } diff --git a/include/asterisk/module.h b/include/asterisk/module.h index e159642c0..1c01d483f 100644 --- a/include/asterisk/module.h +++ b/include/asterisk/module.h @@ -28,12 +28,20 @@ #include "asterisk/utils.h" +#include "asterisk/linkedlists.h" /* we use list macros here */ + #if defined(__cplusplus) || defined(c_plusplus) extern "C" { #endif -/* Every module should provide these functions */ +#ifndef STATIC_MODULE +#define STATIC_MODULE /* empty - symbols are global */ +#else +#undef STATIC_MODULE +#define STATIC_MODULE static /* symbols are static */ +#endif +/* Every module should provide these functions */ /*! * \brief Initialize the module. * @@ -45,7 +53,7 @@ extern "C" { * If the module is not loaded successfully, Asterisk will call its * unload_module() function. */ -int load_module(void); +STATIC_MODULE int load_module(void); /*! * \brief Cleanup all module structures, sockets, etc. @@ -56,7 +64,7 @@ int load_module(void); * * \return Zero on success, or non-zero on error. */ -int unload_module(void); +STATIC_MODULE int unload_module(void); /*! * \brief Provides a usecount. @@ -68,13 +76,13 @@ int unload_module(void); * * \return The module's usecount. */ -int usecount(void); /* How many channels provided by this module are in use? */ +STATIC_MODULE 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 */ +STATIC_MODULE char *description(void); /* Description of this module */ /*! * \brief Returns the ASTERISK_GPL_KEY @@ -91,7 +99,7 @@ char *description(void); /* Description of this module */ * * \return ASTERISK_GPL_KEY */ -char *key(void); /* Return the below mentioned key, unmodified */ +STATIC_MODULE char *key(void); /* Return the below mentioned key, unmodified */ /*! * \brief Reload stuff. @@ -101,7 +109,7 @@ char *key(void); /* Return the below mentioned key, unmodified */ * * \return The return value is not used. */ -int reload(void); /* reload configs */ +STATIC_MODULE int reload(void); /* reload configs */ /*! \brief The text the key() function should return. */ #define ASTERISK_GPL_KEY \ @@ -260,52 +268,66 @@ int ast_register_atexit(void (*func)(void)); */ void ast_unregister_atexit(void (*func)(void)); +/*! + * \brief Given a function address, find the corresponding module. + * This is required as a workaround to the fact that we do not + * have a module argument to the load_module() function. + * Hopefully the performance implications are small. + */ +struct module *ast_find_module(int (*load_fn)(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. - * used to keep track of channels using a given resource. - */ struct localuser { struct ast_channel *chan; - struct localuser *next; + AST_LIST_ENTRY(localuser) next; }; -#define STANDARD_LOCAL_USER /* unused and deprecated now */ +/*! structure used for lock and refcount of module users. + * The mutex protects the usecnt field and whatever needs to be + * protected (typically, a list of struct localuser). + * As a trick, if usecnt is initialized with -1, + * ast_format_register will init the mutex for you. + */ +struct ast_module_lock { + ast_mutex_t lock; + AST_LIST_HEAD_NOLOCK(localuser_head, localuser) u; + int usecnt; /* number of active clients */ +}; + +struct localuser *ast_localuser_add(struct ast_module_lock *m, struct ast_channel *chan); +void ast_localuser_remove(struct ast_module_lock *m, struct localuser *u); +void ast_hangup_localusers(struct ast_module_lock *m); /*! - * \brief The localuser declaration. - * - * This creates a localuser mutex and the head of a list of localusers - * that is used for keeping track of channels using a resource, as well - * as the use count. + * \brief create a localuser mutex and several other variables used for keeping the + * use count. * * <b>Sample Usage:</b> * \code * LOCAL_USER_DECL; * \endcode */ -#define LOCAL_USER_DECL AST_MUTEX_DEFINE_STATIC(localuser_lock); \ - static struct localuser *localusers = NULL; \ - static int localusecnt = 0; +#define LOCAL_USER_DECL \ + static struct ast_module_lock me = { \ + .u = AST_LIST_HEAD_NOLOCK_INIT_VALUE, \ + .usecnt = 0, \ + .lock = AST_MUTEX_INIT_VALUE } -#define STANDARD_USECOUNT_DECL \ - AST_MUTEX_DEFINE_STATIC(localuser_lock); \ - static int localusecnt = 0; +#define STANDARD_USECOUNT_DECL LOCAL_USER_DECL /* XXX lock remains unused */ -#define STANDARD_INCREMENT_USECOUNT \ - ast_mutex_lock(&localuser_lock); \ - localusecnt++; \ - ast_mutex_unlock(&localuser_lock); \ - ast_update_use_count(); +/*! run 'x' protected by lock, then call ast_update_use_count() */ +#define __MOD_PROTECT(x) do { \ + ast_mutex_lock(&me.lock); \ + x; \ + ast_mutex_unlock(&me.lock); \ + ast_update_use_count(); \ + } while (0) -#define STANDARD_DECREMENT_USECOUNT \ - ast_mutex_lock(&localuser_lock); \ - localusecnt--; \ - ast_mutex_unlock(&localuser_lock); \ - ast_update_use_count(); +#define STANDARD_INCREMENT_USECOUNT __MOD_PROTECT(me.usecnt++) +#define STANDARD_DECREMENT_USECOUNT __MOD_PROTECT(me.usecnt--) /*! * \brief Add a localuser. @@ -318,18 +340,11 @@ struct localuser { * \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 = ast_calloc(1, sizeof(*u)))) \ - 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_ADD(u) do { \ + u = ast_localuser_add(&me, chan); \ + if (!u) \ + return -1; \ + } while (0) /*! * \brief Remove a localuser. @@ -338,26 +353,7 @@ 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(); \ -} +#define LOCAL_USER_REMOVE(u) ast_localuser_remove(&me, u) /*! * \brief Hangup all localusers. @@ -365,20 +361,7 @@ struct localuser { * 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(); \ -} +#define STANDARD_HANGUP_LOCALUSERS ast_hangup_localusers(&me) /*! * \brief Set the specfied integer to the current usecount. @@ -396,10 +379,131 @@ struct localuser { * } * \endcode */ -#define STANDARD_USECOUNT(res) { \ - res = localusecnt; \ -} - +#define STANDARD_USECOUNT(res) do { res = me.usecnt; } while (0) + +/* + * XXX The following macro is deprecated, and only used by modules + * in codecs/ and a few other places which do their own manipulation + * of the usecount variable. + * Its use is supposed to be gradually phased away as those modules + * are updated to use the standard mechanism. + */ +#define OLD_STANDARD_USECOUNT(res) do { res = localusecnt; } while (0) + +/*! + * \brief The following is part of the new module management code. + * + * All modules must implement the module API (load, unload...) + * whose functions are exported through fields of a "struct module_symbol"; + * + * Modules exporting extra symbols (data or functions), should list + * them into an array of struct symbol_entry: + * struct symbol_entry exported_symbols[] + * of symbols, with a NULL name on the last entry + * Functions should be added with MOD_FUNC(name), + * data structures with MOD_DATA(_name). + * The array in turn is referenced by struct module_symbol. + * (Typically, a module will export only a single symbol, which points + * to a record containing all the methods. This is the API of the module, + * and should be known to the module's clients as well. + * + * Modules that require symbols supplied by other modules should + * provide an array + * struct symbol_entry required_symbols[] + * of symbols, with a NULL name on the last entry, containing the + * name of the desired symbol. + * For good measure, we also provide the size in both caller and calle + * to figure out if there is a mismatch (not terribly useful because most + * objects are a single word, but still... ) + * The symbol can be added to the array with MOD_WANT(symbol) macro. + * required_symbols is also pointed by through struct module_symbol. + * + * Typically, the whole interface exported by a module should be + * in a single structure named after the module, as follows. + * Say the module high level name is 'foo', then we should have + * - in include/asterisk/foo.h + * struct foo_interface { + * int (*f)(int, char *); -- first function exported + * const char (*g)(int); -- second function exported + * char *buf; + * ... -- other fields + * } + * - in the module exporting the interface, e.g. res/res_foo.c + * static int f(int, char *); + * static const char *g(int); + * const char buf[BUFSZ]; + * struct foo_interface foo = { + * .f = f, + * .g = g, + * .buf = buf, + * } + * + * NOTE: symbol names are 'global' in this module namespace, so it + * will be wiser to name exported symbols with a prefix indicating the module + * supplying it, e.g. foo_f, foo_g, foo_buf. Internally to the module, + * symbols are still static so they can keep short and meaningful names. + * The macros MOD_FIELD and METHOD_BASE() below help setting these entries. + * + * MOD_FIELD(f1), -- field and function name are the same + * METHOD_BASE(foo_, f1), -- field and function name differ by a prefix + * .f1 = function_name, -- generic case + * } + * + * Note that the loader requires that no fields of exported_symbols + * are NULL, because that is used as an indication of the end of the array. + */ + +struct symbol_entry { + const char *name; + void *value; + int size; + struct module *src; /* module sourcing it, filled by loader */ +}; + +/* + * Constructors for symbol_entry values + */ +#define MOD_FUNC(f) { .name = #f, .value = f, .size = sizeof(f) } +#define MOD_DATA(d) { .name = #d, .value = &d, .size = sizeof(_name) } +#define MOD_WANT(s) { .name = #s, .value = &s, 0 } /* required symbols */ + +/* + * Constructors for fields of foo_interface + */ +#define MOD_FIELD(f) . ## f = f +#define METHOD_BASE(_base, _name) . ## _name = _base ## _name + + +struct module_symbols { + int (*load_module)(void); + int (*unload_module)(void); + int (*usecount)(void); + char *(*description)(void); + char *(*key)(void); + int (*reload)(void); + + enum module_type { + MOD_0, /* old module style */ + MOD_1, /* old style, but symbols here */ + MOD_2, /* new style, exported symbols */ + } type; + struct symbol_entry *exported_symbols; + struct symbol_entry *required_symbols; +}; + +#define STD_MOD(t, exp, req) \ +struct module_symbols mod_data = { \ + .load_module = load_module, \ + .unload_module = unload_module, \ + .description = description, \ + .key = key, \ + .reload = reload, \ + .usecount = usecount, \ + .type = t, \ + .exported_symbols = exp, \ + .required_symbols = req \ +}; + #if defined(__cplusplus) || defined(c_plusplus) } #endif @@ -33,6 +33,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$") +#include "asterisk/linkedlists.h" #include "asterisk/module.h" #include "asterisk/options.h" #include "asterisk/config.h" @@ -56,7 +57,6 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$") #define RTLD_NOW 0 #endif - static int modlistver = 0; /* increase whenever the list changes, to protect reload */ static unsigned char expected_key[] = @@ -64,6 +64,23 @@ static unsigned char expected_key[] = 0xff, 0x8b, 0xa9, 0xbe, 0x7c, 0x43, 0x74, 0x63 }; /* + * Modules can be in a number of different states, as below: + * MS_FAILED attempt to load failed. This is final. + * MS_NEW just added to the list, symbols unresolved. + * MS_RESOLVED all symbols resolved, but supplier modules not active yet. + * MS_CANLOAD all symbols resolved and suppliers are all active + * (or we are in a cyclic dependency and we are breaking a loop) + * MS_ACTIVE load() returned successfully. + */ +enum st_t { /* possible states of a module */ + MS_FAILED = 0, /* cannot load */ + MS_NEW = 1, /* nothing known */ + MS_RESOLVED = 2, /* all required resolved */ + MS_CANLOAD = 3, /* as above, plus cyclic depend.*/ + MS_ACTIVE = 4, /* all done */ +}; + +/* * All module symbols are in module_symbols. * Modules are then linked in a list of struct module, * whereas updaters are in a list of struct loadupdate. @@ -73,21 +90,18 @@ static unsigned char expected_key[] = * * A second lock, reloadlock, is used to prevent concurrent reloads */ - -struct module_symbols { - int (*load_module)(void); - int (*unload_module)(void); - int (*usecount)(void); - char *(*description)(void); - char *(*key)(void); - int (*reload)(void); -}; - struct module { AST_LIST_ENTRY(module) next; struct module_symbols cb; void *lib; /* the shared lib */ char resource[256]; + + enum st_t state; + int export_refcount; /* how many users of exported symbols */ + + ast_mutex_t mtx; /* for future use */ + struct localuser *lu; + int localusecnt; }; @@ -101,6 +115,340 @@ static AST_LIST_HEAD_STATIC(updaters, loadupdate); AST_MUTEX_DEFINE_STATIC(reloadlock); /* + * helper localuser routines. + * All of these routines are extremely expensive, so the use of + * macros is totally unnecessary from the point of view of performance: + * the extra function call will be totally negligible in all cases. + */ + +struct localuser *ast_localuser_add(struct ast_module_lock *m, + struct ast_channel *chan) +{ + struct localuser *u = ast_calloc(1, sizeof(*u)); + if (u == NULL) + return NULL; + u->chan = chan; + ast_mutex_lock(&m->lock); + AST_LIST_INSERT_HEAD(&m->u, u, next); + m->usecnt++; + ast_mutex_unlock(&m->lock); + ast_update_use_count(); + return u; +} + +void ast_localuser_remove(struct ast_module_lock *m, struct localuser *u) +{ + ast_mutex_lock(&m->lock); + AST_LIST_REMOVE(&m->u, u, next); + m->usecnt--; + free(u); + ast_mutex_unlock(&m->lock); + ast_update_use_count(); +} + +void ast_hangup_localusers(struct ast_module_lock *m) +{ + struct localuser *u; + ast_mutex_lock(&m->lock); + AST_LIST_TRAVERSE_SAFE_BEGIN(&m->u, u, next) { + ast_softhangup(u->chan, AST_SOFTHANGUP_APPUNLOAD); + free(u); + AST_LIST_REMOVE_CURRENT(&m->u, next); + } + AST_LIST_TRAVERSE_SAFE_END + m->usecnt = 0; + ast_mutex_unlock(&m->lock); + ast_update_use_count(); +} + +/*--- new-style loader routines ---*/ + +/* + * For backward compatibility, we have 3 types of loadable modules: + * + * MOD_0 these are the 'old style' modules, which export a number + * of callbacks, and their full interface, as globally visible + * symbols. The module needs to be loaded with RTLD_LAZY and + * RTLD_GLOBAL to make symbols visible to other modules, and + * to avoid load failures due to cross dependencies. + * + * MOD_1 almost as above, but the generic callbacks are all into a + * a structure, mod_data. Same load requirements as above. + * + * MOD_2 this is the 'new style' format for modules. The module must + * explictly declare which simbols are exported and which + * symbols from other modules are used, and the code in this + * loader will implement appropriate checks to load the modules + * in the correct order. Also this allows to load modules + * with RTLD_NOW and RTLD_LOCAL so there is no chance of run-time + * bugs due to unresolved symbols or name conflicts. + */ + +/* + * helper routine to print the symbolic name associated to a state + */ +static const char *st_name(enum st_t state) +{ + /* try to resolve required symbols */ + const char *st; + switch (state) { +#define ST(x) case x: st = # x; break; + ST(MS_NEW); + ST(MS_FAILED); + ST(MS_RESOLVED); + ST(MS_ACTIVE); + ST(MS_CANLOAD); + default: + st = "unknown"; + } + return st; +#undef ST +} + +/*! \brief + * Fetch/release an exported symbol - modify export_refcount by delta + * \param delta 1 to fetch a symbol, -1 to release it. + * on success, return symbol value. + * Note, modules in MS_FAIL will never match in a 'get' request. + * If src is non-NULL, on exit *src points to the source module. + * + * Must be called with the lock held. + */ +static void *module_symbol_helper(const char *name, + int delta, struct module **src) +{ + void *ret = NULL; + struct module *m; + + AST_LIST_TRAVERSE(&module_list, m, next) { + struct symbol_entry *es; + if (delta > 0 && m->state == MS_FAILED) + continue; /* cannot 'get' a symbol from a failed module */ + for (es = m->cb.exported_symbols; ret == NULL && es && es->name; es++) { + if (!strcmp(es->name, name)) { + ret = es->value; + m->export_refcount += delta; + if (src) + *src = m; + break; + } + } + if (ret) + break; + } + if (ret == NULL) + ast_log(LOG_WARNING, "symbol %s not found\n", name); + return ret; +} + +static void *release_module_symbol(const char *name) +{ + return module_symbol_helper(name, -1, NULL); +} + +static void *get_module_symbol(const char *name, struct module **src) +{ + return module_symbol_helper(name, +1, src); +} + +/*! + * \brief Release refcounts to all imported symbols, + * and change module state to MS_FAILED. + */ +static void release_module(struct module *m) +{ + struct symbol_entry *s; + + for (s = m->cb.required_symbols; s && s->name != NULL; s++) { + if (s->value != NULL) { + release_module_symbol(s->name); + s->value = NULL; + } + } + m->state = MS_FAILED; +} + +/*! \brief check that no NULL symbols are exported - the algorithms rely on that. */ +static int check_exported(struct module *m) +{ + struct symbol_entry *es = m->cb.exported_symbols; + int errors = 0; + + if (es == NULL) + return 0; + ast_log(LOG_WARNING, "module %s exports the following symbols\n", + es->name); + for (; es->name; es++) { + void **p = es->value; + int i; + + ast_log(LOG_WARNING, "\taddr %p size %8d %s\n", + es->value, es->size, es->name); + for (i = 0; i < es->size / sizeof(void *); i++, p++) { + if (*p == NULL) { + ast_log(LOG_WARNING, "\t *** null field at offset %d\n", i); + errors++; + } + } + } + return errors; +} + +/*! + * \brief Resolve symbols and change state accordingly. + * Return 1 if state changed, 0 otherwise. + * If MS_FAILED, MS_ACTIVE or MS_CANLOAD there is nothing to do. + * If a symbol cannot be resolved (no supplier or supplier in MS_FAIL), + * move to MS_FAIL and release all symbols; + * If all suppliers are MS_ACTIVE, move to MS_CANLOAD + * otherwise move to MS_RESOLVED. + */ +static int resolve(struct module *m) +{ + struct symbol_entry *s; + + if (m->state == MS_FAILED || m->state == MS_ACTIVE || m->state == MS_CANLOAD) + return 0; /* already decided what to do */ + /* now it's either MS_NEW or MS_RESOLVED. + * Be optimistic and put it in MS_CANLOAD, then try to + * resolve and verify symbols, and downgrade as appropriate. + */ + m->state = MS_CANLOAD; + for (s = m->cb.required_symbols; s && s->name != NULL; s++) { + void **p = (void **)(s->value); + + if (*p == NULL) /* symbol not resolved yet */ + *p = get_module_symbol(s->name, &s->src); + if (*p == NULL || s->src->state == MS_FAILED) { /* fail */ + ast_log(LOG_WARNING, + "Unresolved symbol %s for module %s\n", + s->name, m->resource); + release_module(m); /* and set to MS_FAILED */ + break; + } + if (s->src->state != MS_ACTIVE) + m->state = MS_RESOLVED; /* downgrade */ + } + return 1; +} + +/* + * Fixup references and load modules according to their dependency order. + * Called when new modules are added to the list. + * The algorithm is as follows: + * - all modules MS_FAILED are changed to MS_NEW, in case something + * happened that could help them. + * - first try to resolve symbols. If successful, change the + * module's state to MS_RESOLVED otherwise to MS_FAILED + * - repeat on all modules until there is progress: + * . if it is MS_ACTIVE or MS_FAILED, continue (no progress) + * . if one has all required modules in MS_ACTIVE, try to load it. + * If successful it becomes MS_ACTIVE itself, otherwise + * MS_FAILED and releases all symbols. + * In any case, we have progress. + * . if one of the dependencies is MS_FAILED, release and set to + * MS_FAILED here too. We have progress. + * - if we have no progress there is a cyclic dependency. + * Take first and change to MS_CANLOAD, i.e. as if all required are + * MS_ACTIVE. we have progress, so repeat. + * NOTE: + * must be called with lock held + * recursive calls simply return success. + */ +static int fixup(const char *caller) +{ + struct module *m; + int total = 0, new = 0, cycle = 0; + static int in_fixup = 0; /* disable recursive calls */ + + if (in_fixup) + return 0; + in_fixup++; + AST_LIST_TRAVERSE(&module_list, m, next) { + total++; + if (m->state == MS_FAILED) + m->state = MS_NEW; + if (m->state == MS_NEW) + new++; + /* print some debugging info for new modules */ + if (m->state == MS_NEW && + (m->cb.exported_symbols || m->cb.required_symbols)) + ast_log(LOG_WARNING, + "module %-30s exports %p requires %p state %s(%d)\n", + m->resource, m->cb.exported_symbols, + m->cb.required_symbols, + st_name(m->state), m->state); + } + ast_log(LOG_WARNING, "---- fixup (%s): %d modules, %d new ---\n", + caller, total, new); + for (;;cycle++) { + int again = 0; /* set if we need another round */ + + ast_log(LOG_WARNING, "---- fixup: cycle %d ---\n", cycle); + AST_LIST_TRAVERSE(&module_list, m, next) { + if (resolve(m)) + again = 1; /* something changed */ + if (m->state != MS_CANLOAD) /* for now, done with this module */ + continue; + /* try to run the load routine */ + if (m->cb.load_module()) { /* error */ + ast_log(LOG_WARNING, "load_module %s fail\n", + m->resource); + release_module(m); /* and set to MS_FAIL */ + } else { + ast_log(LOG_WARNING, "load_module %s success\n", + m->resource); + m->state = MS_ACTIVE; + } + again = 1; /* something has changed */ + } + /* Modules in MS_RESOLVED mean a possible cyclic dependency. + * Break the indecision by setting one to CANLOAD, and repeat. + */ + AST_LIST_TRAVERSE(&module_list, m, next) { + if (m->state == MS_RESOLVED) { + m->state = MS_CANLOAD; + again = 1; + break; + } + } + if (!again) /* we are done */ + break; + } + ast_log(LOG_WARNING, "---- fixup complete ---\n"); + in_fixup--; + return 0; +} + +/* test routines to see which modules depend on global symbols + * exported by other modules. + */ +static void check_symbols(void) +{ + struct dirent *d; + DIR *mods = opendir(ast_config_AST_MODULE_DIR); + void *lib; + char buf[1024]; + + ast_log(LOG_WARNING, "module dir <%s>\n", ast_config_AST_MODULE_DIR); + if (!mods) + return; + while((d = readdir(mods))) { + int ld = strlen(d->d_name); + /* Must end in .so to load it. */ + if (ld <= 3 || strcasecmp(d->d_name + ld - 3, ".so")) + continue; + snprintf(buf, sizeof(buf), "%s/%s", ast_config_AST_MODULE_DIR, d->d_name); + lib = dlopen(buf, RTLD_NOW | RTLD_LOCAL); + if (lib == NULL) { + ast_log(LOG_WARNING, "module %s error %s\n", d->d_name, dlerror()); + } + dlclose(lib); + } +} +/*--- end new-style routines ---*/ + +/* * In addition to modules, the reload command handles some extra keywords * which are listed here together with the corresponding handlers. * This table is also used by the command completion code. @@ -182,6 +530,7 @@ int ast_unload_resource(const char *resource_name, int force) } else ast_log(LOG_WARNING, "** Dangerous **: Unloading resource anyway, at user request\n"); } + release_module(cur); /* bookkeeping */ AST_LIST_REMOVE_CURRENT(&module_list, next); dlclose(cur->lib); free(cur); @@ -222,6 +571,24 @@ char *ast_module_helper(const char *line, const char *word, int pos, int state, return ret; } +/*! + * \brief Given a function address, find the corresponding module. + * This is required as a workaround to the fact that we do not + * have a module argument to the load_module() function. + * Hopefully the performance implications are small. + */ +struct module *ast_find_module(int (*load_fn)(void)) +{ + struct module *cur; + AST_LIST_LOCK(&module_list); + AST_LIST_TRAVERSE(&module_list, cur, next) { + if (cur->cb.load_module == load_fn) + break; + } + AST_LIST_UNLOCK(&module_list); + return cur; +} + int ast_module_reload(const char *name) { struct module *cur; @@ -305,13 +672,14 @@ static void *find_symbol(struct module *m, const char *name, int verbose) } /* XXX cfg is only used for !res_* and #ifdef RTLD_GLOBAL */ -static int __load_resource(const char *resource_name, const struct ast_config *cfg) +static struct module * __load_resource(const char *resource_name, + const struct ast_config *cfg) { static char fn[256]; int errors=0; int res; struct module *cur; - struct module_symbols *m; + struct module_symbols *m, *m1; int flags=RTLD_NOW; unsigned char *key; char tmp[80]; @@ -339,11 +707,11 @@ static int __load_resource(const char *resource_name, const struct ast_config *c if (resource_exists(resource_name, 0)) { ast_log(LOG_WARNING, "Module '%s' already exists\n", resource_name); AST_LIST_UNLOCK(&module_list); - return -1; + return NULL; } if (!(cur = ast_calloc(1, sizeof(*cur)))) { AST_LIST_UNLOCK(&module_list); - return -1; + return NULL; } m = &cur->cb; ast_copy_string(cur->resource, resource_name, sizeof(cur->resource)); @@ -351,29 +719,45 @@ static int __load_resource(const char *resource_name, const struct ast_config *c ast_copy_string(fn, resource_name, sizeof(fn)); else snprintf(fn, sizeof(fn), "%s/%s", ast_config_AST_MODULE_DIR, resource_name); + /* first, open in a sane way */ + cur->lib = dlopen(fn, RTLD_NOW | RTLD_LOCAL); + if (cur->lib == NULL) { + ast_log(LOG_WARNING, "test %s\n", dlerror()); + } else + dlclose(cur->lib); + cur->lib = dlopen(fn, flags); if (!cur->lib) { ast_log(LOG_WARNING, "%s\n", dlerror()); free(cur); AST_LIST_UNLOCK(&module_list); - return -1; + return NULL; + } + m1 = find_symbol(cur, "mod_data", 0); + if (m1 != NULL) { /* new style module */ + errors = check_exported(cur); + *m = *m1; + if (m->type == MOD_2) + ast_log(LOG_WARNING, "new style %s, should unload and reload with RTLD_LOCAL\n", resource_name); + } else { + m->type = MOD_0; + m->load_module = find_symbol(cur, "load_module", 1); + m->unload_module = find_symbol(cur, "unload_module", 1); + m->usecount = find_symbol(cur, "usecount", 1); + m->description = find_symbol(cur, "description", 1); + m->key = find_symbol(cur, "key", 1); + m->reload = find_symbol(cur, "reload", 0); } - m->load_module = find_symbol(cur, "load_module", 1); if (!m->load_module) errors++; - m->unload_module = find_symbol(cur, "unload_module", 1); if (!m->unload_module) errors++; - m->usecount = find_symbol(cur, "usecount", 1); if (!m->usecount) errors++; - m->description = find_symbol(cur, "description", 1); if (!m->description) errors++; - m->key = find_symbol(cur, "key", 1); if (!m->key) errors++; - m->reload = find_symbol(cur, "reload", 0); if (!m->key || !(key = (unsigned char *) m->key())) { ast_log(LOG_WARNING, "Key routine returned NULL in module %s\n", fn); key = NULL; @@ -388,7 +772,7 @@ static int __load_resource(const char *resource_name, const struct ast_config *c dlclose(cur->lib); free(cur); AST_LIST_UNLOCK(&module_list); - return -1; + return NULL; } if (!ast_fully_booted) { if (option_verbose) @@ -405,30 +789,64 @@ static int __load_resource(const char *resource_name, const struct ast_config *c so reload commands will be issued in same order modules were loaded */ modlistver++; + if (m->type == MOD_2) { + ast_log(LOG_WARNING, "new-style module %s, deferring load()\n", + resource_name); + cur->state = MS_NEW; + } else + cur->state = MS_CANLOAD; + /* XXX TODO: make sure the usecount is 1 before releasing the lock */ AST_LIST_UNLOCK(&module_list); - if ((res = m->load_module())) { + + if (cur->state == MS_CANLOAD && (res = m->load_module())) { ast_log(LOG_WARNING, "%s: load_module failed, returning %d\n", resource_name, res); ast_unload_resource(resource_name, 0); - return -1; + return NULL; } + cur->state = MS_ACTIVE; ast_update_use_count(); - return 0; + return cur; } +/* + * load a single module (API call). + * (recursive calls from load_module() succeed. + * Returns 0 on success, -1 on error. + */ int ast_load_resource(const char *resource_name) { - int res, o = option_verbose; + int o = option_verbose; struct ast_config *cfg = NULL; + struct module *m; option_verbose = 0; /* Keep the module file parsing silent */ cfg = ast_config_load(AST_MODULE_CONFIG); option_verbose = o; /* restore verbosity */ - res = __load_resource(resource_name, cfg); + m = __load_resource(resource_name, cfg); if (cfg) ast_config_destroy(cfg); - return res; + return m ? 0 : -1; } +#if 0 +/* + * load a single module (API call). + * (recursive calls from load_module() succeed. + */ +int ast_load_resource(const char *resource_name) +{ + struct module *m; + int ret; + + ast_mutex_lock(&modlock); + m = __load_resource(resource_name, 0); + fixup(resource_name); + ret = (m->state == MS_FAILED) ? -1 : 0; + ast_mutex_unlock(&modlock); + return ret; +} +#endif + /* if enabled, log and output on console the module's name, and try load it */ static int print_and_load(const char *s, struct ast_config *cfg) { @@ -441,7 +859,7 @@ static int print_and_load(const char *s, struct ast_config *cfg) term_color(tmp, s, COLOR_BRWHITE, 0, sizeof(tmp))); fflush(stdout); } - if (!__load_resource(s, cfg)) + if (__load_resource(s, cfg)) return 0; /* success */ ast_log(LOG_WARNING, "Loading module %s failed!\n", s); return -1; @@ -458,7 +876,6 @@ static const char *loadorder[] = int load_modules(const int preload_only) { struct ast_config *cfg; - struct ast_variable *v; int x; if (option_verbose) { @@ -467,9 +884,13 @@ int load_modules(const int preload_only) "Asterisk Dynamic Loader Starting:\n"); } + check_symbols(); + cfg = ast_config_load(AST_MODULE_CONFIG); + if (cfg) { const char *cmd = preload_only ? "preload" : "load"; + struct ast_variable *v; /* Load explicitly defined modules */ for (v = ast_variable_browse(cfg, "modules"); v; v = v->next) { if (strcasecmp(v->name, cmd)) /* not what we are looking for */ @@ -481,16 +902,12 @@ int load_modules(const int preload_only) } } - if (preload_only) { - ast_config_destroy(cfg); - return 0; - } + if (preload_only) + goto done; - if (cfg && !ast_true(ast_variable_retrieve(cfg, "modules", "autoload"))) { + if (cfg && !ast_true(ast_variable_retrieve(cfg, "modules", "autoload"))) /* no autoload */ - ast_config_destroy(cfg); - return 0; - } + goto done; /* * Load all modules. To help resolving dependencies, we load modules * in the order defined by loadorder[], with the final step for @@ -517,9 +934,10 @@ int load_modules(const int preload_only) !strcasecmp(d->d_name + ld - 3, ".so") && !resource_exists(d->d_name, 1)) { /* It's a shared library, check if we are allowed to load it - * (very inefficient, but oh well. + * (very inefficient, but oh well). */ if (cfg) { + struct ast_variable *v; for (v = ast_variable_browse(cfg, "modules"); v; v = v->next) { if (!strcasecmp(v->name, "noload") && !strcasecmp(v->value, d->d_name)) @@ -543,6 +961,8 @@ int load_modules(const int preload_only) } closedir(mods); } +done: + fixup("load_modules"); ast_config_destroy(cfg); return 0; } @@ -557,7 +977,6 @@ void ast_update_use_count(void) AST_LIST_TRAVERSE(&updaters, m, next) m->updater(); AST_LIST_UNLOCK(&module_list); - } int ast_update_module_list(int (*modentry)(const char *module, const char *description, int usecnt, const char *like), diff --git a/res/res_smdi.c b/res/res_smdi.c index e8607ebe1..8adab88d1 100644 --- a/res/res_smdi.c +++ b/res/res_smdi.c @@ -59,8 +59,7 @@ static int smdi_load(int reload); /* Use count stuff */ -AST_MUTEX_DEFINE_STATIC(localuser_lock); -static int localusecnt = 0; +STANDARD_USECOUNT_DECL; /*! \brief SMDI interface container. */ struct ast_smdi_interface_container { @@ -505,10 +504,7 @@ void ast_smdi_interface_destroy(struct ast_smdi_interface *iface) ASTOBJ_CONTAINER_DESTROY(&iface->mwi_q); free(iface); - ast_mutex_lock(&localuser_lock); - localusecnt--; - ast_mutex_unlock(&localuser_lock); - ast_update_use_count(); + STANDARD_DECREMENT_USECOUNT; } /*! @@ -692,10 +688,7 @@ static int smdi_load(int reload) ASTOBJ_CONTAINER_LINK(&smdi_ifaces, iface); ASTOBJ_UNREF(iface, ast_smdi_interface_destroy); - ast_mutex_lock(&localuser_lock); - localusecnt++; - ast_mutex_unlock(&localuser_lock); - ast_update_use_count(); + STANDARD_INCREMENT_USECOUNT; } else { ast_log(LOG_NOTICE, "Ignoring unknown option %s in %s\n", v->name, config_file); } |