Reorganize files to base/ folder (#1)

src/base/pool.c

@@ -0,0 +1,57 @@
+#include "pool.h"
+
+APool *apool_create_ex(Allocator *allocator, U32 n_elements, U32 element_size, U32 element_align)
+{
+    Assert(IsPow2(element_align));
+    U32 align = element_align;
+    if (element_align < alignof(APoolElement)) {
+        element_align = alignof(APoolElement);
+    }
+    U32 size = AlignUp(element_size, element_align);
+
+    APool *pool = allocator_push_type(allocator, APool);
+    Assert(pool != NULL);
+    pool->align = align;
+    pool->element_size = size;
+    pool->allocator = allocator;
+    pool->n_elements = n_elements;
+    pool->free_list = NULL;
+    pool->start = NULL;
+
+    if (size != APOOL_AUTOGROW) {
+        Assert(n_elements <= U32_Max / size );
+        U32 total_size = n_elements * size;
+        U8 * start = allocator_push(allocator, total_size, align);
+        for (U32 i = 0; i < total_size; i += size) {
+            APoolElement *element = (APoolElement *)&start[i];
+            element->next = pool->free_list;
+            pool->free_list = element;
+        }
+        pool->start = start;
+    }
+
+    return pool;
+}
+
+void *apool_alloc(APool *pool)
+{
+    APoolElement *element = pool->free_list;
+    if (element != NULL) {
+        pool->free_list = element->next;
+    } else if(pool->n_elements == APOOL_AUTOGROW) {
+        element = allocator_push(pool->allocator, pool->element_size, pool->align);
+    }
+
+    return element;
+}
+
+void apool_free(APool *pool, void *ptr)
+{
+    if (ptr != NULL) {
+        Assert((U8 *)ptr >= pool->start);
+
+        APoolElement *element = (APoolElement *)ptr;
+        element->next = pool->free_list;
+        pool->free_list = element;
+    }
+}