Definitions for arena memory management.

src/base/base_arena.h

@@ -0,0 +1,58 @@
+#ifndef BASE_ARENA_H
+#define BASE_ARENA_H
+
+// Constants
+#define ARENA_HEADER_SIZE 64
+
+// Types
+typedef u32 ArenaFlags;
+enum { ArenaFlag_NoChain = (1 << 0); ArenaFlag_LargePages = (1 << 1); };
+
+typedef struct ArenaParams ArenaParams;
+struct ArenaParams {
+  ArenaFlags flags;
+  u64 reserve_size;
+  u64 commite_size;
+  void *optional_backing_buffer; // NOTE(tijani): ??
+};
+
+typedef struct Arena Arena;
+struct Arena {
+  Arena *previous; // Previous arena in the chain
+  Arena *current;  // Current arena in the chain
+  ArenaFlags flags;
+  u32 commit_size;
+  u64 reserve_size;
+  u64 base_position;
+  u64 position;
+  u64 commit;
+  u64 reserve;
+};
+
+typedef struct Temp Temp;
+struct Temp {
+  Arena *arena;
+  u64 position;
+};
+
+// creation, destruction
+internal Arena *arena_alloc_(ArenaParams *params);
+#define arena_alloc(...) arena_alloc_(&(ArenaParams){.reserve_size = MB(64), .commit_size = KB(64), __VA_ARGS__})
+internal void arena_releas(Arena *arena);
+
+// push, pop operations
+internal void *arena_psuh(Arena *arena, u64 size, u64 align);
+internal u64 arena_position(Arena *arena);
+internal void arena_pop_to(Arena *arena, u64 position);
+internal void arena_clear(Arena *arena);
+internal void arena_pop(Arena *arena, u64 amount);
+#define push_array_no_zero_aligned(a, T, c, align) (T *)arena_push((a), sizeof(T) * (c), (align))
+#define push_array_aligned(a, T, c, align) (T *)MemoryZero(push_array_no_zero_aligned(a, T, c, align), sizeof(T) * (c))
+#define push_array_no_zero(a, T, c) push_array_no_zero_aligned(a, T, c, Max(8, Align_Of(T)))
+#define push_array(a, T, c) push_array_aligned(a, T, c, Max(8, Align_Of(T)))
+
+// Temp
+internal Temp temp_begin(Arena *arena);
+internal void temp_end(Temp temp);
+
+#endif // BASE_ARENA_H

src/base/base_core.h

@@ -1,10 +1,12 @@
 #ifndef BASE_CORE_H
 #define BASE_CORE_H
 
-#define global static
-#define local static 
-#define internal static
+// Foreigns
+#include <string.h>
 
+#define global static
+#define local static
+#define internal static
 
 // Base Types
 typedef uint8_t u8;
@@ -25,5 +27,27 @@ typedef s64 b64;
 typedef float f32;
 typedef double f64;
 
+// Units
+#define KB(n) (((u64)(n)) << 10)
+#define MB(n) (((u64)(n)) << 20)
+#define GB(n) (((u64)(n)) << 30)
+#define TB(n) (((u64)(n)) << 40)
+#define Thousand(n) ((n) * 1000)
+#define Million(n) ((n) * 1000000)
+#define Billion(n) ((n) * 1000000000)
+
+// Memory operations
+#define MemoryZero(dest, count) memset((dest), 0, (count))
+
+// Max, Min
+#define Max(A, B) (((A) > (B)) ? (A) : (B))
+#define Min(A, B) (((A) < (B)) ? (A) : (B))
+
+// Type Alignment
+#if COMPILER_MSVC
+ #define Align_Of(T) __alignof(T)
+#else
+ #error Align_Of not defined for this compiler.
+#endif
 
 #endif // BASE_CORE_H

src/base/base_inc.h

@@ -10,5 +10,4 @@
 
 // clang-format on
 
-
 #endif // BASE_INC_H