Pool

poolsclosed/simpe_pool.c

@@ -0,0 +1,47 @@
+#include <malloc.h>
+#include <string.h>
+
+/* See: https://8dcc.github.io/programming/pool-allocator.html */
+
+#define CHUNK_SIZE 64
+
+typedef union Chunk Chunk;
+union Chunk {
+    Chunk *next; // When not null, it is used
+    char arr[CHUNK_SIZE];
+};
+
+typedef struct Pool Pool;
+struct Pool {
+    Chunk *free_chunk; // Pointer to a linked list of free chunks
+    Chunk *chunk_arr;
+};
+
+void *pool_alloc(Pool *pool) {
+    if (pool == NULL || pool->free_chunk == NULL)
+        return NULL;
+
+    // Pop a new one from the free list
+    Chunk *result = pool->free_chunk;
+    pool->free_chunk = pool->free_chunk->next;
+
+    return result;
+}
+
+void pool_free(Pool *pool, void *ptr) {
+    if (pool == NULL || ptr == NULL)
+        return;
+
+    // This can be done withuot an intermediate ptr
+    Chunk *freed = ptr;
+    freed->next = pool->free_chunk;
+    pool->free_chunk = freed;
+}
+
+void pool_close(Pool *pool) {
+    if (pool == NULL)
+        return;
+
+    free(pool->chunk_arr);
+    free(pool);
+}