Add owl_ptr_array_free convenience function

Unfortunately, most uses of GPtrArray here require a two-step chant
which is really annoying. Until we require glib 2.22 and get
g_ptr_array_new_with_free_func, use this helper function.

buddylist.c

@@ -133,6 +133,5 @@ void owl_buddylist_clear(owl_buddylist *bl)
 
 void owl_buddylist_cleanup(owl_buddylist *bl)
 {
-  g_ptr_array_foreach(bl->buddies, (GFunc)owl_buddy_delete, NULL);
-  g_ptr_array_free(bl->buddies, true);
+  owl_ptr_array_free(bl->buddies, (GDestroyNotify)owl_buddy_delete);
 }

functions.c

@@ -2778,8 +2778,7 @@ void owl_function_zpunt(const char *class, const char *inst, const char *recip,
   }
 
   owl_function_punt(argv->len, (const char *const*) argv->pdata, direction);
-  g_ptr_array_foreach(argv, (GFunc)g_free, NULL);
-  g_ptr_array_free(argv, true);
+  owl_ptr_array_free(argv, g_free);
 }
 
 void owl_function_punt(int argc, const char *const *argv, int direction)
@@ -3072,8 +3071,7 @@ void owl_function_buddylist(int aim, int zephyr, const char *filename)
           }
         }
       }
-      g_ptr_array_foreach(anyone, (GFunc)g_free, NULL);
-      g_ptr_array_free(anyone, true);
+      owl_ptr_array_free(anyone, g_free);
     }
   }
 #endif
@@ -3417,8 +3415,7 @@ void owl_function_zephyr_buddy_check(int notify)
     }
   }
 
-  g_ptr_array_foreach(anyone, (GFunc)g_free, NULL);
-  g_ptr_array_free(anyone, true);
+  owl_ptr_array_free(anyone, g_free);
 #endif
 }
 

keymap.c

@@ -23,8 +23,7 @@ void owl_keymap_cleanup(owl_keymap *km)
 {
   g_free(km->name);
   g_free(km->desc);
-  g_ptr_array_foreach(km->bindings, (GFunc)owl_keybinding_delete, NULL);
-  g_ptr_array_free(km->bindings, true);
+  owl_ptr_array_free(km->bindings, (GDestroyNotify)owl_keybinding_delete);
 }
 
 void owl_keymap_set_parent(owl_keymap *km, const owl_keymap *parent)

util.c

@@ -97,6 +97,15 @@ CALLER_OWN char *owl_util_makepath(const char *in)
   return(out);
 }
 
+void owl_ptr_array_free(GPtrArray *array, GDestroyNotify element_free_func)
+{
+  /* TODO: when we move to requiring glib 2.22+, use
+   * g_ptr_array_new_with_free_func instead. */
+  if (element_free_func)
+    g_ptr_array_foreach(array, (GFunc)element_free_func, NULL);
+  g_ptr_array_free(array, true);
+}
+
 /* Break a command line up into argv, argc.  The caller must free
    the returned values with g_strfreev.  If there is an error argc will be set
    to -1, argv will be NULL and the caller does not need to free anything. The
@@ -169,10 +178,7 @@ CALLER_OWN char **owl_parseline(const char *line, int *argc)
 
   /* check for unbalanced quotes */
   if (quote!='\0') {
-    /* TODO: when we move to requiring glib 2.22+, use
-     * g_ptr_array_new_with_free_func. */
-    g_ptr_array_foreach(argv, (GFunc)g_free, NULL);
-    g_ptr_array_free(argv, true);
+    owl_ptr_array_free(argv, g_free);
     if (argc) *argc = -1;
     return(NULL);
   }

zwrite.c

@@ -347,8 +347,7 @@ void owl_zwrite_delete(owl_zwrite *z)
 
 void owl_zwrite_cleanup(owl_zwrite *z)
 {
-  g_ptr_array_foreach(z->recips, (GFunc)g_free, NULL);
-  g_ptr_array_free(z->recips, true);
+  owl_ptr_array_free(z->recips, g_free);
   g_free(z->cmd);
   g_free(z->zwriteline);
   g_free(z->class);