Arenas and start work on strings

1 files changed, 58 insertions, 0 deletions

diff --git a/src/ez_arena.c b/src/ez_arena.c
new file mode 100644
index 0000000..e37766e
--- /dev/null
+++ b/src/ez_arena.c
@@ -0,0 +1,58 @@
+#include "ez_arena.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+ez_arena_t *ez_arena_create(u64 size, b32 zero_out) {
+    ez_arena_t *alloc = malloc(size + sizeof(ez_arena_t));
+
+    if (!alloc) {
+        return NULL;
+    }
+
+    if (zero_out) {
+        memset((u8*)alloc+EZ_ARENA_BASE_POS, 0, size);
+    }
+
+    *alloc = (ez_arena_t){ .alloc_size = size, .pos = EZ_ARENA_BASE_POS };
+
+    return alloc;
+}
+
+void *ez_arena_alloc(ez_arena_t *arena, u64 alloc_amount) {
+    u64 pos_aligned = ALIGN_UP_POW2(arena->pos, ARENA_ALIGN);
+    u64 new_pos = pos_aligned + alloc_amount;
+
+    if (new_pos > arena->alloc_size + sizeof(ez_arena_t)) { return NULL; }
+
+    arena->pos = new_pos;
+
+    u8* out = (u8*)arena + pos_aligned;
+
+    memset(out, 0, alloc_amount);
+
+    return out;
+}
+
+void *ez_arena_alloc_nz(ez_arena_t *arena, u64 alloc_amount) {
+    u64 pos_aligned = ALIGN_UP_POW2(arena->pos, ARENA_ALIGN);
+    u64 new_pos = pos_aligned + alloc_amount;
+
+    if (new_pos > arena->alloc_size + sizeof(ez_arena_t)) { return NULL; }
+
+    arena->pos = new_pos;
+
+    return (u8*)arena + pos_aligned;
+}
+
+void ez_arena_clear(ez_arena_t *arena, b32 zero_out) {
+    if (zero_out) {
+        memset((u8*)arena+EZ_ARENA_BASE_POS, 0, arena->alloc_size);
+    }
+
+    arena->pos = EZ_ARENA_BASE_POS;
+}
+
+void ez_arena_destroy(ez_arena_t *arena) {
+    free(arena);
+}