[asterisk-commits] trunk r15784 - in /trunk: ./ codecs/
include/asterisk/ res/
asterisk-commits at lists.digium.com
asterisk-commits at lists.digium.com
Tue Mar 28 14:15:17 MST 2006
Author: rizzo
Date: Tue Mar 28 15:15:10 2006
New Revision: 15784
URL: http://svn.digium.com/view/asterisk?rev=15784&view=rev
Log:
Bring in the new loader code as described in mantis #4377
and updated to today's version.
The core of the patch is only two files, loader.c
and include/asterisk/module.h, with the other files
touched only to adapt non-standard usages of the
reference counts and localuser lists.
Modified:
trunk/codecs/codec_a_mu.c
trunk/codecs/codec_adpcm.c
trunk/codecs/codec_alaw.c
trunk/codecs/codec_g723_1.c
trunk/codecs/codec_g726.c
trunk/codecs/codec_gsm.c
trunk/codecs/codec_ilbc.c
trunk/codecs/codec_lpc10.c
trunk/codecs/codec_speex.c
trunk/codecs/codec_ulaw.c
trunk/include/asterisk/module.h
trunk/loader.c
trunk/res/res_smdi.c
Modified: trunk/codecs/codec_a_mu.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_a_mu.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_a_mu.c (original)
+++ trunk/codecs/codec_a_mu.c Tue Mar 28 15:15:10 2006
@@ -316,7 +316,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/codecs/codec_adpcm.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_adpcm.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_adpcm.c (original)
+++ trunk/codecs/codec_adpcm.c Tue Mar 28 15:15:10 2006
@@ -616,7 +616,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/codecs/codec_alaw.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_alaw.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_alaw.c (original)
+++ trunk/codecs/codec_alaw.c Tue Mar 28 15:15:10 2006
@@ -416,7 +416,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/codecs/codec_g723_1.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_g723_1.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_g723_1.c (original)
+++ trunk/codecs/codec_g723_1.c Tue Mar 28 15:15:10 2006
@@ -407,7 +407,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/codecs/codec_g726.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_g726.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_g726.c (original)
+++ trunk/codecs/codec_g726.c Tue Mar 28 15:15:10 2006
@@ -1078,7 +1078,7 @@
usecount (void)
{
int res;
- STANDARD_USECOUNT (res);
+ OLD_STANDARD_USECOUNT (res);
return res;
}
Modified: trunk/codecs/codec_gsm.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_gsm.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_gsm.c (original)
+++ trunk/codecs/codec_gsm.c Tue Mar 28 15:15:10 2006
@@ -347,7 +347,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/codecs/codec_ilbc.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_ilbc.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_ilbc.c (original)
+++ trunk/codecs/codec_ilbc.c Tue Mar 28 15:15:10 2006
@@ -307,7 +307,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/codecs/codec_lpc10.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_lpc10.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_lpc10.c (original)
+++ trunk/codecs/codec_lpc10.c Tue Mar 28 15:15:10 2006
@@ -420,7 +420,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/codecs/codec_speex.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_speex.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_speex.c (original)
+++ trunk/codecs/codec_speex.c Tue Mar 28 15:15:10 2006
@@ -602,7 +602,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/codecs/codec_ulaw.c
URL: http://svn.digium.com/view/asterisk/trunk/codecs/codec_ulaw.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/codecs/codec_ulaw.c (original)
+++ trunk/codecs/codec_ulaw.c Tue Mar 28 15:15:10 2006
@@ -418,7 +418,7 @@
int usecount(void)
{
int res;
- STANDARD_USECOUNT(res);
+ OLD_STANDARD_USECOUNT(res);
return res;
}
Modified: trunk/include/asterisk/module.h
URL: http://svn.digium.com/view/asterisk/trunk/include/asterisk/module.h?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/include/asterisk/module.h (original)
+++ trunk/include/asterisk/module.h Tue Mar 28 15:15:10 2006
@@ -26,14 +26,22 @@
#ifndef _ASTERISK_MODULE_H
#define _ASTERISK_MODULE_H
+#include "asterisk/linkedlists.h" /* XXX needed here */
+
#include "asterisk/utils.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
+#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 @@
* 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 @@
*
* \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 @@
*
* \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 @@
*
* \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 @@
*
* \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 \
@@ -260,50 +268,66 @@
*/
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;
};
-/*!
- * \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.
+/*! 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 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 STANDARD_USECOUNT_DECL \
- AST_MUTEX_DEFINE_STATIC(localuser_lock); \
- 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();
+#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 LOCAL_USER_DECL /* XXX lock remains unused */
+
+/*! 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_INCREMENT_USECOUNT __MOD_PROTECT(me.usecnt++)
+#define STANDARD_DECREMENT_USECOUNT __MOD_PROTECT(me.usecnt--)
/*!
* \brief Add a localuser.
@@ -316,18 +340,11 @@
* \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.
@@ -336,26 +353,7 @@
* 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.
@@ -363,20 +361,7 @@
* 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.
@@ -394,10 +379,131 @@
* }
* \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
Modified: trunk/loader.c
URL: http://svn.digium.com/view/asterisk/trunk/loader.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/loader.c (original)
+++ trunk/loader.c Tue Mar 28 15:15:10 2006
@@ -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"
@@ -57,12 +58,28 @@
#define RTLD_NOW 0
#endif
-
static int modlistver = 0; /* increase whenever the list changes, to protect reload */
static unsigned char expected_key[] =
{ 0x8e, 0x93, 0x22, 0x83, 0xf5, 0xc3, 0xc0, 0x75,
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.
@@ -74,21 +91,18 @@
*
* 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; /* XXX use yet ? */
+ struct localuser *lu;
+ int localusecnt;
};
@@ -100,6 +114,340 @@
static AST_LIST_HEAD_STATIC(module_list, module);
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, "(notice only) 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
@@ -184,6 +532,7 @@
} else
ast_log(LOG_WARNING, "** Dangerous **: Unloading resource anyway, at user request\n");
}
+ release_module(cur); /* XXX */
AST_LIST_REMOVE_CURRENT(&module_list, next);
dlclose(cur->lib);
free(cur);
@@ -222,6 +571,24 @@
}
}
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)
@@ -307,13 +674,14 @@
}
/* 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];
@@ -341,11 +709,11 @@
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));
@@ -353,29 +721,47 @@
ast_copy_string(fn, resource_name, sizeof(fn));
else
snprintf(fn, sizeof(fn), "%s/%s", ast_config_AST_MODULE_DIR, resource_name);
+#if 0
+ /* XXX test, 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);
+#endif
+
cur->lib = dlopen(fn, flags);
if (!cur->lib) {
ast_log(LOG_WARNING, "%s\n", dlerror());
free(cur);
AST_LIST_UNLOCK(&module_list);
- return -1;
- }
- m->load_module = find_symbol(cur, "load_module", 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);
+ }
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;
@@ -390,7 +776,7 @@
dlclose(cur->lib);
free(cur);
AST_LIST_UNLOCK(&module_list);
- return -1;
+ return NULL;
}
if (!ast_fully_booted) {
if (option_verbose)
@@ -407,29 +793,63 @@
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 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)
@@ -443,7 +863,7 @@
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;
@@ -460,7 +880,6 @@
int load_modules(const int preload_only)
{
struct ast_config *cfg;
- struct ast_variable *v;
int x;
if (option_verbose) {
@@ -469,9 +888,14 @@
"Asterisk Dynamic Loader Starting:\n");
}
+ if (0)
+ 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 */
@@ -483,16 +907,12 @@
}
}
- if (preload_only) {
- ast_config_destroy(cfg);
- return 0;
- }
-
- if (cfg && !ast_true(ast_variable_retrieve(cfg, "modules", "autoload"))) {
+ if (preload_only)
+ goto done;
+
+ 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
@@ -519,9 +939,10 @@
!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))
@@ -545,6 +966,8 @@
}
closedir(mods);
}
+done:
+ fixup("load_modules");
ast_config_destroy(cfg);
return 0;
}
@@ -559,7 +982,6 @@
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),
Modified: trunk/res/res_smdi.c
URL: http://svn.digium.com/view/asterisk/trunk/res/res_smdi.c?rev=15784&r1=15783&r2=15784&view=diff
==============================================================================
--- trunk/res/res_smdi.c (original)
+++ trunk/res/res_smdi.c Tue Mar 28 15:15:10 2006
@@ -740,12 +740,6 @@
ASTOBJ_CONTAINER_DESTROYALL(&smdi_ifaces, ast_smdi_interface_destroy);
ASTOBJ_CONTAINER_DESTROY(&smdi_ifaces);
- /*
- * localusers = NULL; is just to silence the compiler warning
- * about an unused variable. It will be removed soon, when the
- * LOCALUSER-related functions are rewritten.
- */
- localusers = NULL;
return 0;
}
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