2 /* module.c : Implementation of the module loading/unloading mechanism.
6 #include <lttv/module.h>
14 GPtrArray
*dependents
;
18 /* Table of loaded modules and paths where to search for modules */
20 static GHashTable
*modules
= NULL
;
22 static GPtrArray
*modulesPaths
= NULL
;
24 static void lttv_module_unload_all();
27 void lttv_module_init(int argc
, char **argv
)
29 modules
= g_hash_table_new(g_str_hash
, g_str_equal
);
30 modulesPaths
= g_ptr_array_new();
34 void lttv_module_destroy()
38 /* Unload all modules */
39 lttv_module_unload_all();
41 /* Free the modules paths pointer array as well as the elements */
42 for(i
= 0; i
< modulesPaths
->len
; i
++) {
43 g_free(modulesPaths
->pdata
[i
]);
45 g_ptr_array_free(modulesPaths
,TRUE
) ;
48 /* destroy the hash table */
49 g_hash_table_destroy(modules
) ;
54 /* Add a new pathname to the modules loading search path */
56 void lttv_module_path_add(const char *name
)
58 g_ptr_array_add(modulesPaths
,(char*)g_strdup(name
));
63 module_load(const char *name
, int argc
, char **argv
)
73 const char *module_name
;
75 LttvModuleInit init_function
;
77 /* Try to find the module along all the user specified paths */
79 for(i
= 0 ; i
< modulesPaths
->len
; i
++) {
80 pathname
= g_module_build_path(modulesPaths
->pdata
[i
],name
);
81 gm
= g_module_open(pathname
,G_MODULE_BIND_LAZY
);
82 g_critical("loading module : %s", pathname
);
83 g_critical("module error : %s", g_module_error());
89 /* Try the default system path */
92 pathname
= g_module_build_path(NULL
,name
);
93 gm
= g_module_open(pathname
,G_MODULE_BIND_LAZY
);
94 g_critical("loading module : %s", pathname
);
98 /* Module cannot be found */
99 if(gm
== NULL
) return NULL
;
101 /* Check if the module was already opened using the hopefully canonical name
102 returned by g_module_name. */
104 module_name
= g_module_name(gm
);
106 m
= g_hash_table_lookup(modules
, module_name
);
110 /* Module loaded for the first time. Insert it in the table and call the
111 init function if any. */
113 m
= g_new(LttvModule
, 1);
117 m
->dependents
= g_ptr_array_new();
118 g_hash_table_insert(modules
, (gpointer
)module_name
, m
);
120 if(!g_module_symbol(gm
, "init", (gpointer
)&init_function
)) {
121 g_warning("module %s (%s) has no init function", name
, pathname
);
123 else init_function(m
, argc
, argv
);
127 /* Module was already opened, check that it really is the same and
128 undo the extra g_module_open */
130 if(m
->module
!= gm
) g_error("Two gmodules with the same pathname");
140 lttv_module_load(const char *name
, int argc
, char **argv
)
142 LttvModule
*m
= module_load(name
, argc
, argv
);
143 if(m
!= NULL
) m
->load_count
++;
149 lttv_module_require(LttvModule
*m
, const char *name
, int argc
, char **argv
)
153 module
= module_load(name
, argc
, argv
);
154 if(module
!= NULL
) g_ptr_array_add(m
->dependents
, module
);
159 static void module_unload(LttvModule
*m
)
161 LttvModuleDestroy destroy_function
;
167 /* Decrement the reference count */
170 if(m
->ref_count
> 0) return;
172 /* We really have to unload the module, first unload its dependents */
174 len
= m
->dependents
->len
;
176 for(i
= 0 ; i
< len
; i
++) {
177 module_unload(m
->dependents
->pdata
[i
]);
180 if(len
!= m
->dependents
->len
) g_error("dependents list modified");
182 /* Unload the module itself */
184 if(!g_module_symbol(m
->module
, "destroy", (gpointer
)&destroy_function
)) {
185 g_warning("module (%s) has no destroy function", pathname
);
187 else destroy_function();
189 g_hash_table_remove(modules
, g_module_name(m
->module
));
190 g_ptr_array_free(m
->dependents
, TRUE
);
191 g_module_close(m
->module
);
196 void lttv_module_unload(LttvModule
*m
)
198 if(m
->load_count
<= 0) {
199 g_error("more unload than load (%s)", g_module_name(m
->module
));
208 list_modules(gpointer key
, gpointer value
, gpointer user_data
)
210 g_ptr_array_add((GPtrArray
*)user_data
, value
);
215 lttv_module_list(guint
*nb
)
217 GPtrArray
*list
= g_ptr_array_new();
221 g_hash_table_foreach(modules
, list_modules
, list
);
223 array
= (LttvModule
**)list
->pdata
;
224 g_ptr_array_free(list
, FALSE
);
230 lttv_module_info(LttvModule
*m
, const char **name
,
231 guint
*ref_count
, guint
*load_count
, guint
*nb_dependents
)
233 guint i
, len
= m
->dependents
->len
;
235 LttvModule
**array
= g_new(LttvModule
*, len
);
237 *name
= g_module_name(m
->module
);
238 *ref_count
= m
->ref_count
;
239 *load_count
= m
->load_count
;
240 *nb_dependents
= len
;
241 for(i
= 0 ; i
< len
; i
++) array
[i
] = m
->dependents
->pdata
[i
];
247 list_independent(gpointer key
, gpointer value
, gpointer user_data
)
249 LttvModule
*m
= (LttvModule
*)value
;
251 if(m
->load_count
> 0) g_ptr_array_add((GPtrArray
*)user_data
, m
);
256 lttv_module_unload_all()
262 GPtrArray
*independent_modules
= g_ptr_array_new();
264 g_hash_table_foreach(modules
, list_independent
, independent_modules
);
266 for(i
= 0 ; i
< independent_modules
->len
; i
++) {
267 m
= (LttvModule
*)independent_modules
->pdata
[i
];
268 while(m
->load_count
> 0) lttv_module_unload(m
);
271 g_ptr_array_free(independent_modules
, TRUE
);
272 if(g_hash_table_size(modules
) != 0) g_warning("cannot unload all modules");