Added the ability to run deinit tasks when deleting arenas

src/arena_allocator.c

@@ -30,7 +30,8 @@ Arena *arena_init(Arena *parent, size_t capacity) {
                              .begin = region,
                              .end = region,
                              .child = NULL,
-                             .sibling = NULL};
+                             .sibling = NULL,
+                             .deinit_task_top = NULL};
 
     // if parent has no children this arena is now it's child
     if (parent->child == NULL) {
@@ -50,7 +51,8 @@ Arena *arena_init(Arena *parent, size_t capacity) {
                    .begin = region,
                    .end = region,
                    .child = NULL,
-                   .sibling = NULL};
+                   .sibling = NULL,
+                   .deinit_task_top = NULL};
   return arena;
 }
 
@@ -65,6 +67,13 @@ void arena_deinit(Arena *arena) {
     arena_deinit(current_child);
   }
 
+  // Run deinit tasks before freeing data
+  while (arena->deinit_task_top != NULL) {
+    assert(arena->deinit_task_top->func_ptr != NULL);
+    arena->deinit_task_top->func_ptr(arena->deinit_task_top->func_param);
+    arena->deinit_task_top = arena->deinit_task_top->next;
+  }
+
   // actually free the data
   assert(arena->begin != NULL && arena->end != NULL);
   Region *region = arena->begin;
@@ -117,7 +126,11 @@ void *arena_alloc(Arena *arena, size_t size) {
   return result;
 }
 
-// void *arena_clear(Arena *arena) {
-//   arena->size = 0;
-//   return arena->data;
-// }
+void arena_deinit_task_push(Arena *arena, ArenaDeinitTask task) {
+  ArenaDeinitTask *job = arena_alloc(arena, sizeof(ArenaDeinitTask));
+  *job = task;
+
+  ArenaDeinitTask *next_job = arena->deinit_task_top;
+  arena->deinit_task_top = job;
+  job->next = next_job;
+}

src/arena_allocator.h

@@ -10,6 +10,13 @@ struct Region_s {
   unsigned char data[];
 };
 
+typedef struct ArenaDeinitTask_s ArenaDeinitTask;
+struct ArenaDeinitTask_s {
+  void *func_param;
+  void (*func_ptr)(void *);
+  ArenaDeinitTask *next;
+};
+
 typedef struct Arena_s Arena;
 struct Arena_s {
   Arena *parent;
@@ -17,10 +24,13 @@ struct Arena_s {
   Arena *sibling;
   Region *begin;
   Region *end;
+  ArenaDeinitTask *deinit_task_top;
 };
 
 Arena *arena_init(Arena *parent, size_t capacity);
 void arena_deinit(Arena *arena);
 
+void arena_deinit_task_push(Arena *arena, ArenaDeinitTask task);
+
 void *arena_alloc(Arena *arena, size_t size);
 // void *arena_clear(Arena *arena);

src/main.c

@@ -1,5 +1,6 @@
 #include <GL/glew.h>
 #include <SDL3/SDL.h>
+#include <stdio.h>
 #include <stdlib.h>
 
 #include "SDL3/SDL_events.h"
@@ -10,7 +11,9 @@
 
 #include "arena_allocator.h"
 
-/*
+void test_task(void *data) {
+  printf("\ttest task has been run: %s\n", (char *)data);
+}
 int main(int argc, char *argv[]) {
   // arena allocation test
   printf("Allocation test\n");
@@ -33,6 +36,17 @@ int main(int argc, char *argv[]) {
   Arena *greatsiblinggreatgrandchild_arena =
       arena_init(greatgrandchildsiblingsibling_arena, 0);
 
+  printf("deinit task creation tests\n");
+
+  ArenaDeinitTask task = {NULL};
+  task.func_ptr = *test_task;
+  task.func_param = "parameter";
+
+  arena_deinit_task_push(global_arena, task);
+
+  task.func_param = "2nd parameter added";
+  arena_deinit_task_push(global_arena, task);
+
   printf("deinit tests\n");
   arena_deinit(greatgrandchild_arena);
 
@@ -40,8 +54,8 @@ int main(int argc, char *argv[]) {
 
   printf("tests complete\n");
 }
-*/
 
+/*
 int main(int argc, char *argv[]) {
   wn_window window = {0};
   if (!wn_window_init(&window)) {
@@ -156,3 +170,4 @@ int main(int argc, char *argv[]) {
 
   return EXIT_SUCCESS;
 }
+*/