listalloc OK (#158)

src/code/listalloc.c

@@ -0,0 +1,63 @@
+#include "listalloc.h"
+#include "libc64/malloc.h"
+
+ListAlloc* ListAlloc_Init(ListAlloc* this) {
+    this->prev = NULL;
+    this->next = NULL;
+    return this;
+}
+
+void* ListAlloc_Alloc(ListAlloc* this, size_t size) {
+    ListAlloc* ptr = malloc(size + sizeof(ListAlloc));
+    ListAlloc* next;
+
+    if (ptr == NULL) {
+        return NULL;
+    }
+
+    next = this->next;
+    if (next != NULL) {
+        next->next = ptr;
+    }
+
+    ptr->prev = next;
+    ptr->next = NULL;
+    this->next = ptr;
+
+    if (this->prev == NULL) {
+        this->prev = ptr;
+    }
+
+    return (u8*)ptr + sizeof(ListAlloc);
+}
+
+void ListAlloc_Free(ListAlloc* this, void* data) {
+    ListAlloc* ptr = &((ListAlloc*)data)[-1];
+
+    if (ptr->prev != NULL) {
+        ptr->prev->next = ptr->next;
+    }
+
+    if (ptr->next != NULL) {
+        ptr->next->prev = ptr->prev;
+    }
+
+    if (this->prev == ptr) {
+        this->prev = ptr->next;
+    }
+
+    if (this->next == ptr) {
+        this->next = ptr->prev;
+    }
+
+    free(ptr);
+}
+
+void ListAlloc_FreeAll(ListAlloc* this) {
+    ListAlloc* iter = this->prev;
+
+    while (iter != NULL) {
+        ListAlloc_Free(this, (u8*)iter + sizeof(ListAlloc));
+        iter = this->prev;
+    }
+}