Offer an API for both stack and map to set a data dtor to be called for autofree data.

Author: FedeDP

Lib/map.c

@@ -25,6 +25,7 @@ struct _map {
     int table_size;
     int size;
     map_elem *data;
+    map_dtor dtor;
 };
 
 static unsigned long crc32(const unsigned char *s, unsigned int len);
@@ -205,7 +206,11 @@ static void clear_elem(map_t *m, const int idx) {
     m->data[idx].key_needs_free = false;
 
     if (m->data[idx].val_needs_free) {
-        memhook._free((void *)m->data[idx].data);
+        if (m->dtor) {
+            m->dtor(m->data[idx].data);
+        } else {
+            memhook._free((void *)m->data[idx].data);
+        }
     }
     m->data[idx].data = NULL;
     m->data[idx].val_needs_free = false;
@@ -324,6 +329,7 @@ map_ret_code map_clear(map_t *m) {
             clear_elem(m, i);
         }
     }
+    m->dtor = NULL;
     return MAP_OK;
 }
 
@@ -342,3 +348,9 @@ int map_length(const map_t *m) {
     MOD_ASSERT(m, "NULL map.", MAP_WRONG_PARAM);
     return m->size;
 }
+
+map_ret_code map_set_dtor(map_t *m, map_dtor fn) {
+    MOD_ASSERT(m, "NULL map.", MAP_WRONG_PARAM);
+    m->dtor = fn;
+    return MAP_OK;
+}

Lib/public/module/map.h

@@ -16,6 +16,9 @@ typedef enum {
 /* Callback for map_iterate */
 typedef map_ret_code (*map_cb)(void *, void *);
 
+/* Fn for map_set_dtor */
+typedef map_ret_code (*map_dtor)(void *);
+
 /* Incomplete struct declaration for hashmap */
 typedef struct _map map_t;
 
@@ -32,6 +35,7 @@ _public_ map_ret_code map_remove(map_t *m, const char *key);
 _public_ map_ret_code map_clear(map_t *m);
 _public_ map_ret_code map_free(map_t *m);
 _public_ int map_length(const map_t *m);
+_public_ map_ret_code map_set_dtor(map_t *m, map_dtor fn);
 
 #ifdef __cplusplus
 }

Lib/public/module/stack.h

@@ -13,7 +13,10 @@ typedef enum {
 } stack_ret_code;
 
 /* Callback for stack_iterate */
-typedef stack_ret_code (*stack_cb)(void *, void *);
+typedef stack_ret_code(*stack_cb)(void *, void *);
+
+/* Fn for stack_set_dtor */
+typedef stack_ret_code(*stack_dtor)(void *);
 
 /* Incomplete struct declaration for stack */
 typedef struct _stack stack_t;
@@ -30,6 +33,7 @@ _public_ void *stack_peek(const stack_t *s);
 _public_ stack_ret_code stack_clear(stack_t *s);
 _public_ stack_ret_code stack_free(stack_t *s);
 _public_ int stack_length(const stack_t *s);
+_public_ stack_ret_code stack_set_dtor(stack_t *s, stack_dtor fn);
 
 #ifdef __cplusplus
 }

Lib/stack.c

@@ -8,6 +8,7 @@ typedef struct _elem {
 
 struct _stack {
     int len;
+    stack_dtor dtor;
     stack_elem *data;
 };
 
@@ -74,9 +75,14 @@ stack_ret_code stack_clear(stack_t *s) {
         const bool autofree = elem->autofree;
         void *data = stack_pop(s);
         if (autofree) {
-            memhook._free(data);
+            if (s->dtor) {
+                s->dtor(data);
+            } else {
+                memhook._free(data);
+            }
         }
     }
+    s->dtor = NULL;
     return STACK_OK;
 }
 
@@ -90,6 +96,11 @@ stack_ret_code stack_free(stack_t *s) {
 
 int stack_length(const stack_t *s) {
     MOD_ASSERT(s, "NULL stack.", STACK_WRONG_PARAM);
-    
     return s->len;
 }
+
+stack_ret_code stack_set_dtor(stack_t *s, stack_dtor fn) {
+    MOD_ASSERT(s, "NULL stack.", STACK_WRONG_PARAM);
+    s->dtor = fn;
+    return STACK_OK;
+}

TODO.md

@@ -37,12 +37,14 @@ module_ref should then return a new self_t* object, add it to a stack in module.
 - [x] Add _clear function
 - [x] Add tests!
 - [x] Update doc!
+- [x] Offer a stack_set_dtor() API to offer a callback to free each item when autofree is true
 
 ### Map API
 - [x] Add _clear function
 - [x] Add tests!
 - [x] Fix issue in map_new if m->data calloc fails: map object was not memsetted to 0; it would lead to a crash when map_free was called
 - [x] Update doc!
+- [x] Offer a map_set_dtor() to offer a callback to free each item when autofree is true
 
 ### Fix
 - [x] Actually honor current module's callback when flushing pubsub messages
@@ -54,7 +56,6 @@ module_ref should then return a new self_t* object, add it to a stack in module.
 
 ## 4.1.0
 - [ ] PoisonPill message to automatically stop another module?
-- [ ] Expose a queue and use it for internally storing each module's fds
 
 ## Ideas
 - [ ] Let contexts talk together? Eg: broadcast(msg, bool global) to send a message to all modules in every context; module_publish message in another context? etc etc

docs/src/map.rst

@@ -24,6 +24,9 @@ Structures
 
     /* Callback for map_iterate */
     typedef map_ret_code (*map_cb)(void *, void *);
+    
+    /* Fn for map_set_dtor */
+    typedef map_ret_code (*map_dtor)(void *);
 
     /* Incomplete struct declaration for hashmap */
     typedef struct _map map_t;
@@ -52,7 +55,7 @@ Where not specified, these functions return a map_ret_code.
 
 .. c:function:: map_put(m, key, val, dupkey, autofree)
 
-  Put a value inside hashmap. Note that if dupkey is true, key will be strdupped; it will also be automatically freed upon deletion.
+  Put a value inside hashmap. Note that if dupkey is true, key will be strdupped and its lifetime will be managed by libmodule.
 
   :param m: pointer to map_t
   :param key: key for this value
@@ -96,7 +99,7 @@ Where not specified, these functions return a map_ret_code.
 
 .. c:function:: map_clear(m)
 
-  Clears a map object by deleting any object inside map, and eventually freeing it too if marked with autofree.
+  Clears a map object by deleting any object inside map, and eventually freeing it too if marked with autofree. Note that map dtor (if any) will be set to NULL too.
 
   :param s: pointer to map_t
   :type s: :c:type:`map_t *`
@@ -115,3 +118,12 @@ Where not specified, these functions return a map_ret_code.
   :param m: pointer to map_t
   :type m: :c:type:`map_t *`
   :returns: map length or a map_ret_code if any error happens (map_t is null).
+  
+.. c:function:: map_set_dtor(m, fn)
+
+  Set a function to be called upon data deletion for autofree elements.
+
+  :param m: pointer to map_t
+  :param fn: pointer dtor callback
+  :type m: :c:type:`map_t *`
+  :type fn: :c:type:`map_dtor`

docs/src/stack.rst

@@ -23,6 +23,9 @@ Structures
 
     /* Callback for stack_iterate */
     typedef stack_ret_code (*stack_cb)(void *, void *);
+    
+    /* Fn for stack_set_dtor */
+    typedef stack_ret_code(*stack_dtor)(void *);
 
     /* Incomplete struct declaration for stack */
     typedef struct _stack stack_t;
@@ -78,7 +81,7 @@ Where not specified, these functions return a stack_ret_code.
 
 .. c:function:: stack_clear(s)
 
-  Clears a stack object by deleting any object inside stack, and eventually freeing it too if marked with autofree.
+  Clears a stack object by deleting any object inside stack, and eventually freeing it too if marked with autofree. Note that stack dtor (if any) will be set to NULL too.
 
   :param s: pointer to stack_t
   :type s: :c:type:`stack_t *`
@@ -98,3 +101,11 @@ Where not specified, these functions return a stack_ret_code.
   :type s: :c:type:`stack_t *`
   :returns: stack length or a stack_ret_code if any error happens (stack_t is null).
 
+.. c:function:: stack_set_dtor(s, fn)
+
+  Set a function to be called upon data deletion for autofree elements.
+
+  :param s: pointer to stack_t
+  :param fn: pointer dtor callback
+  :type s: :c:type:`stack_t *`
+  :type fn: :c:type:`stack_dtor`