initial

1 files changed, 42 insertions, 0 deletions

diff --git a/prb_memory.c b/prb_memory.c
new file mode 100644
index 0000000..4bceccc
--- /dev/null
+++ b/prb_memory.c
@@ -0,0 +1,42 @@
+Arena *arena_alloc(U64 cap)
+{
+	Arena *arena = 0;
+
+	/* TODO(pryazha): Use OS related memory allocator (like VirtualAlloc on Windows) */
+	arena = malloc(sizeof(Arena));
+	Assert(arena);
+
+	if (!cap)
+		cap = DEFAULT_ALLOC_SIZE;
+
+	arena->mem = malloc(cap);
+	Assert(arena->mem);
+	arena->cap = cap;
+	arena->used = 0;
+
+	return arena;
+}
+
+void arena_release(Arena *arena)
+{
+	free(arena->mem);
+	arena->mem = 0;
+	arena->cap = 0;
+	arena->used = 0;
+	free(arena);
+}
+
+void *arena_push(Arena *arena, U64 size)
+{
+	Assert(arena->used+size <= arena->cap);
+	void *r = arena->mem+arena->used;
+	arena->used += size;
+	return r;
+}
+
+void arena_pop(Arena *arena, U64 amount)
+{
+	Assert(arena);
+	U64 clamped = ClampTop(amount, arena->used);
+	arena->used = arena->used-clamped;
+}