Version 0.1.0 from FTP
authorMark Spencer <markster@digium.com>
Thu, 28 Oct 1999 20:38:23 +0000 (20:38 +0000)
committerMark Spencer <markster@digium.com>
Thu, 28 Oct 1999 20:38:23 +0000 (20:38 +0000)
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@14 65c4cc65-6c06-0410-ace0-fbb531ad65f3

loader.c [new file with mode: 0755]

diff --git a/loader.c b/loader.c
new file mode 100755 (executable)
index 0000000..af52f65
--- /dev/null
+++ b/loader.c
@@ -0,0 +1,322 @@
+/*
+ * Asterisk -- A telephony toolkit for Linux.
+ *
+ * Module Loader
+ * 
+ * Copyright (C) 1999, Adtran Inc. and Linux Support Services, LLC
+ *
+ * Mark Spencer <markster@linux-support.net>
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License
+ */
+
+#include <stdio.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <asterisk/module.h>
+#include <asterisk/options.h>
+#include <asterisk/config.h>
+#include <asterisk/logger.h>
+#include <dlfcn.h>
+#define __USE_GNU
+#include <pthread.h>
+#include "asterisk.h"
+
+struct module {
+       int (*load_module)(void);
+       int (*unload_module)(void);
+       int (*usecount)(void);
+       char *(*description)(void);
+       void *lib;
+       char resource[256];
+       struct module *next;
+};
+
+static struct loadupdate {
+       int (*updater)(void);
+       struct loadupdate *next;
+} *updaters = NULL;
+
+static pthread_mutex_t modlock = PTHREAD_MUTEX_INITIALIZER;
+
+static struct module *module_list=NULL;
+
+int ast_unload_resource(char *resource_name, int force)
+{
+       struct module *m, *ml = NULL;
+       int res = -1;
+       if (pthread_mutex_lock(&modlock))
+               ast_log(LOG_WARNING, "Failed to lock\n");
+       m = module_list;
+       while(m) {
+               if (!strcasecmp(m->resource, resource_name)) {
+                       if ((res = m->usecount()) > 0)  {
+                               if (force) 
+                                       ast_log(LOG_WARNING, "Warning:  Forcing removal of module %s with use count %d\n", resource_name, res);
+                               else {
+                                       ast_log(LOG_WARNING, "Soft unload failed, '%s' has use count %d\n", resource_name, res);
+                                       pthread_mutex_unlock(&modlock);
+                                       return -1;
+                               }
+                       }
+                       res = m->unload_module();
+                       if (res) {
+                               ast_log(LOG_WARNING, "Firm unload failed for %s\n", resource_name);
+                               if (force <= AST_FORCE_FIRM) {
+                                       pthread_mutex_unlock(&modlock);
+                                       return -1;
+                               } else
+                                       ast_log(LOG_WARNING, "** Dangerous **: Unloading resource anyway, at user request\n");
+                       }
+                       if (ml)
+                               ml->next = m->next;
+                       else
+                               module_list = m->next;
+                       dlclose(m->lib);
+                       free(m);
+               }
+               ml = m;
+               m = m->next;
+       }
+       pthread_mutex_unlock(&modlock);
+       ast_update_use_count();
+       return res;
+}
+
+int ast_load_resource(char *resource_name)
+{
+       static char fn[256];
+       int errors=0;
+       int res;
+       struct module *m = malloc(sizeof(struct module));
+       if (!m) {
+               ast_log(LOG_WARNING, "Out of memory\n");
+               return -1;
+       }
+       strncpy(m->resource, resource_name, sizeof(m->resource));
+       if (resource_name[0] == '/') {
+               strncpy(fn, resource_name, sizeof(fn));
+       } else {
+               snprintf(fn, sizeof(fn), "%s/%s", AST_MODULE_DIR, resource_name);
+       }
+       m->lib = dlopen(fn, RTLD_NOW  | RTLD_GLOBAL);
+       if (!m->lib) {
+               ast_log(LOG_WARNING, "%s\n", dlerror());
+               free(m);
+               return -1;
+       }
+       m->load_module = dlsym(m->lib, "load_module");
+       if (!m->load_module) {
+               ast_log(LOG_WARNING, "No load_module in module %s\n", fn);
+               errors++;
+       }
+       m->unload_module = dlsym(m->lib, "unload_module");
+       if (!m->unload_module) {
+               ast_log(LOG_WARNING, "No unload_module in module %s\n", fn);
+               errors++;
+       }
+       m->usecount = dlsym(m->lib, "usecount");
+       if (!m->usecount) {
+               ast_log(LOG_WARNING, "No usecount in module %s\n", fn);
+               errors++;
+       }
+       m->description = dlsym(m->lib, "description");
+       if (!m->description) {
+               ast_log(LOG_WARNING, "No description in module %s\n", fn);
+               errors++;
+       }
+       if (errors) {
+               ast_log(LOG_WARNING, "%d error(s) loading module %s, aborted\n", errors, fn);
+               dlclose(m->lib);
+               free(m);
+               return -1;
+       }
+       if (option_verbose) 
+               ast_verbose( " => (%s)\n", m->description());
+       if ((res = m->load_module())) {
+               ast_log(LOG_WARNING, "%s: load_module failed, returning %d\n", m->resource, fn, res);
+               free(m);
+               return -1;
+       }
+       if (pthread_mutex_lock(&modlock))
+               ast_log(LOG_WARNING, "Failed to lock\n");
+       m->next = module_list;
+       module_list = m;
+       pthread_mutex_unlock(&modlock);
+       ast_update_use_count();
+       return 0;
+}      
+
+int ast_resource_exists(char *resource)
+{
+       struct module *m;
+       if (pthread_mutex_lock(&modlock))
+               ast_log(LOG_WARNING, "Failed to lock\n");
+       m = module_list;
+       while(m) {
+               if (!strcasecmp(resource, m->resource))
+                       break;
+               m = m->next;
+       }
+       pthread_mutex_unlock(&modlock);
+       if (m)
+               return -1;
+       else
+               return 0;
+}
+
+int load_modules()
+{
+       struct ast_config *cfg;
+       struct ast_variable *v;
+       if (option_verbose) 
+               ast_verbose( "Asterisk Dynamic Loader Starting:\n");
+       cfg = ast_load(AST_MODULE_CONFIG);
+       if (cfg) {
+               /* Load explicitly defined modules */
+               v = ast_variable_browse(cfg, "modules");
+               while(v) {
+                       if (!strcasecmp(v->name, "load")) {
+                               if (option_debug && !option_verbose)
+                                       ast_log(LOG_DEBUG, "Loading module %s\n", v->value);
+                               if (option_verbose) {
+                                       ast_verbose( " [%s]", v->value);
+                                       fflush(stdout);
+                               }
+                               if (ast_load_resource(v->value)) {
+                                       ast_log(LOG_WARNING, "Loading module %s failed!\n", v->value);
+                                       if (cfg)
+                                               ast_destroy(cfg);
+                                       return -1;
+                               }
+                       }
+                       v=v->next;
+               }
+       }
+       if (!cfg || ast_true(ast_variable_retrieve(cfg, "modules", "autoload"))) {
+               /* Load all modules */
+               DIR *mods;
+               struct dirent *d;
+               mods = opendir(AST_MODULE_DIR);
+               if (mods) {
+                       while((d = readdir(mods))) {
+                               /* Must end in .so to load it.  */
+                               if ((strlen(d->d_name) > 3) && 
+                                   !strcasecmp(d->d_name + strlen(d->d_name) - 3, ".so") &&
+                                       !ast_resource_exists(d->d_name)) {
+                                       /* It's a shared library -- Just be sure we're allowed to load it -- kinda
+                                          an inefficient way to do it, but oh well. */
+                                       if (cfg) {
+                                               v = ast_variable_browse(cfg, "modules");
+                                               while(v) {
+                                                       if (!strcasecmp(v->name, "noload") &&
+                                                           !strcasecmp(v->value, d->d_name)) 
+                                                               break;
+                                                       v = v->next;
+                                               }
+                                               if (v) {
+                                                       if (option_verbose) {
+                                                               ast_verbose( VERBOSE_PREFIX_1 "[skipping %s]\n", d->d_name);
+                                                               fflush(stdout);
+                                                       }
+                                                       continue;
+                                               }
+                                               
+                                       }
+                                   if (option_debug && !option_verbose)
+                                               ast_log(LOG_DEBUG, "Loading module %s\n", d->d_name);
+                                       if (option_verbose) {
+                                               ast_verbose( VERBOSE_PREFIX_1 "[%s]", d->d_name);
+                                               fflush(stdout);
+                                       }
+                                       if (ast_load_resource(d->d_name)) {
+                                               ast_log(LOG_WARNING, "Loading module %s failed!\n", d->d_name);
+                                               if (cfg)
+                                                       ast_destroy(cfg);
+                                               return -1;
+                                       }
+                               }
+                       };
+               } else {
+                       if (!option_quiet)
+                               ast_log(LOG_WARNING, "Unable to open modules directory " AST_MODULE_DIR ".\n");
+               }
+       } 
+       ast_destroy(cfg);
+       return 0;
+}
+
+void ast_update_use_count(void)
+{
+       /* Notify any module monitors that the use count for a 
+          resource has changed */
+       struct loadupdate *m;
+       if (pthread_mutex_lock(&modlock))
+               ast_log(LOG_WARNING, "Failed to lock\n");
+       m = updaters;
+       while(m) {
+               m->updater();
+               m = m->next;
+       }
+       pthread_mutex_unlock(&modlock);
+       
+}
+
+int ast_update_module_list(int (*modentry)(char *module, char *description, int usecnt))
+{
+       struct module *m;
+       int unlock = -1;
+       if (pthread_mutex_trylock(&modlock))
+               unlock = 0;
+       m = module_list;
+       while(m) {
+               modentry(m->resource, m->description(), m->usecount());
+               m = m->next;
+       }
+       if (unlock)
+               pthread_mutex_unlock(&modlock);
+       return 0;
+}
+
+int ast_loader_register(int (*v)(void)) 
+{
+       struct loadupdate *tmp;
+       /* XXX Should be more flexible here, taking > 1 verboser XXX */
+       if ((tmp = malloc(sizeof (struct loadupdate)))) {
+               tmp->updater = v;
+               if (pthread_mutex_lock(&modlock))
+                       ast_log(LOG_WARNING, "Failed to lock\n");
+               tmp->next = updaters;
+               updaters = tmp;
+               pthread_mutex_unlock(&modlock);
+               return 0;
+       }
+       return -1;
+}
+
+int ast_loader_unregister(int (*v)(void))
+{
+       int res = -1;
+       struct loadupdate *tmp, *tmpl=NULL;
+       if (pthread_mutex_lock(&modlock))
+               ast_log(LOG_WARNING, "Failed to lock\n");
+       tmp = updaters;
+       while(tmp) {
+               if (tmp->updater == v)  {
+                       if (tmpl)
+                               tmpl->next = tmp->next;
+                       else
+                               updaters = tmp->next;
+                       break;
+               }
+               tmpl = tmp;
+               tmp = tmp->next;
+       }
+       if (tmp)
+               res = 0;
+       pthread_mutex_unlock(&modlock);
+       return res;
+}