Merge branch 'temp' into 'main'

This reverts commit d4313fb8e4.

.gitignore

@@ -1,4 +1,7 @@
 .cache
 .vscode
+test
+test.*
+*.dSYM
 compile_commands.json
 libwapp.so

compile

@@ -1,18 +1,66 @@
 #!/bin/bash
 
+BUILD_TYPE="debug"
+
+while [[ $# > 0 ]];do
+  case $1 in
+    --release)
+      BUILD_TYPE="release"
+      shift
+      ;;
+    *|-*|--*)
+      echo "Unknown option $1"
+      exit 1
+      ;;
+  esac
+done
+
 CC=clang
+CFLAGS="-Wall -Werror -pedantic "
+LIBFLAGS="-fPIC -shared"
 INCLUDE="\
-	-Ialiases \
+  $(find src -type d | xargs -I{} echo -n "-I{} ") \
-	-Icpath/include \
+"
-	-Idstr/include \
+TEST_INCLUDE="\
-	$(find mem/include -type d | xargs -I{} echo -n "-I{} ") \
+  $(find tests -type d | xargs -I{} echo -n "-I{} ") \
 "
 SRC="\
-	cpath/src/*.c \
+  $(find src -type f -name "*.c" | xargs -I{} echo -n "{} ") \
-	dstr/src/*.c \
+"
-	mem/src/*/*.c \
+TEST_SRC="\
+  $(find tests -type f -name "*.c" | xargs -I{} echo -n "{} ") \
 "
-CFLAGS="-O3 -shared -fPIC -Wall -Werror -pedantic"
-OUT="libwapp.so"
 
-(set -x ; $CC $CFLAGS $INCLUDE $SRC -o $OUT)
+if [[ $BUILD_TYPE == "release" ]]; then
+  CFLAGS+="-O3"
+else
+  CFLAGS+="-g -fsanitize=address -fsanitize=undefined"
+fi
+
+OUT="libwapp.so"
+TEST_OUT="./wapptest"
+
+# Compile tests
+if [[ $(echo $TEST_SRC | xargs) != "" ]]; then
+  (set -x ; $CC $CFLAGS $INCLUDE $TEST_INCLUDE $SRC $TEST_SRC -o $TEST_OUT)
+fi
+
+# Run tests and exit on failure
+if [[ -f $TEST_OUT ]]; then
+  $TEST_OUT
+  STATUS="$?"
+
+  rm $TEST_OUT
+
+  if [[ $STATUS != "0" ]]; then
+    exit 1
+  fi
+fi
+
+# Compile library
+(set -x ; $CC $CFLAGS $LIBFLAGS $INCLUDE $SRC -o $OUT)
+
+# Compile test.c if it exists
+if [[ -f ./test.c ]]; then
+  (set -x ; $CC $CFLAGS $INCLUDE $SRC ./test.c -o test)
+fi

mem/include/allocator/mem_allocator.h

@@ -1,40 +0,0 @@
-#ifndef MEM_ALLOCATOR_H
-#define MEM_ALLOCATOR_H
-
-#include "aliases.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif // __cplusplus
-
-typedef void *(MemAllocFunc)(u64 size, void *alloc_obj);
-typedef void *(MemAllocAlignedFunc)(u64 size, u64 alignment, void *alloc_obj);
-typedef void *(MemReallocFunc)(void *ptr, u64 size, void *alloc_obj);
-typedef void *(MemReallocAlignedFunc)(void *ptr, u64 size, u64 alignment,
-                                      void *alloc_obj);
-typedef void(MemFreeFunc)(void **ptr, void *alloc_obj);
-
-typedef struct allocator Allocator;
-struct allocator {
-  void *obj;
-  MemAllocFunc *alloc;
-  MemAllocAlignedFunc *alloc_aligned;
-  MemReallocFunc *realloc;
-  MemReallocAlignedFunc *realloc_aligned;
-  MemFreeFunc *free;
-};
-
-void *wapp_mem_allocator_alloc(const Allocator *allocator, u64 size);
-void *wapp_mem_allocator_alloc_aligned(const Allocator *allocator, u64 size,
-                                       u64 alignment);
-void *wapp_mem_allocator_realloc(const Allocator *allocator, void *ptr,
-                                 u64 size);
-void *wapp_mem_allocator_realloc_aligned(const Allocator *allocator, void *ptr,
-                                         u64 size, u64 alignment);
-void wapp_mem_allocator_free(const Allocator *allocator, void **ptr);
-
-#ifdef __cplusplus
-}
-#endif // __cplusplus
-
-#endif // !MEM_ALLOCATOR_H

mem/include/arena/mem_arena.h

@@ -1,28 +0,0 @@
-#ifndef MEM_ARENA_H
-#define MEM_ARENA_H
-
-#include "aliases.h"
-#include "mem_allocator.h"
-#include <stdbool.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif // __cplusplus
-
-typedef struct growing_arena Arena;
-
-Allocator wapp_mem_arena_allocator(const Arena *arena);
-bool wapp_mem_arena_init(Arena **arena, u64 base_capacity);
-void *wapp_mem_arena_alloc(Arena *arena, u64 size);
-void *wapp_mem_arena_alloc_aligned(Arena *arena, u64 size, u64 alignment);
-void *wapp_mem_arena_realloc(Arena *arena, void *ptr, u64 size);
-void *wapp_mem_arena_realloc_aligned(Arena *arena, void *ptr, u64 size,
-                                     u64 alignment);
-void wapp_mem_arena_clear(Arena *arena);
-void wapp_mem_arena_free(Arena **arena);
-
-#ifdef __cplusplus
-}
-#endif // __cplusplus
-
-#endif // !MEM_ARENA_H

mem/include/ctx/mem_ctx.h

@@ -1,32 +0,0 @@
-#ifndef MEM_CTX_H
-#define MEM_CTX_H
-
-#include "mem_allocator.h"
-#include "mem_arena.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif // __cplusplus
-
-typedef enum {
-  CTX_DEST_BUFFER_MAIN,
-  CTX_DEST_BUFFER_TEMP,
-
-  COUNT_CTX_DEST_BUFFER,
-} CTXDestBuffer;
-
-Allocator wapp_mem_ctx_allocator(CTXDestBuffer buffer);
-void wapp_mem_ctx_init(u64 main_buf_capacity, u64 temp_buf_capacity);
-void *wapp_mem_ctx_alloc(CTXDestBuffer buffer, u64 size);
-void *wapp_mem_ctx_alloc_aligned(CTXDestBuffer buffer, u64 size, u64 alignment);
-void *wapp_mem_ctx_realloc(CTXDestBuffer buffer, void *ptr, u64 size);
-void *wapp_mem_ctx_realloc_aligned(CTXDestBuffer buffer, void *ptr, u64 size,
-                                   u64 alignment);
-void wapp_mem_ctx_clear(CTXDestBuffer buffer);
-void wapp_mem_ctx_free(void);
-
-#ifdef __cplusplus
-}
-#endif // __cplusplus
-
-#endif // !MEM_CTX_H

mem/include/libc/mem_libc.h

@@ -1,15 +0,0 @@
-#ifndef MEM_LIBC_H
-#define MEM_LIBC_H
-
-#include "mem_allocator.h"
-#ifdef __cplusplus
-extern "C" {
-#endif // __cplusplus
-
-Allocator wapp_mem_libc_allocator(void);
-
-#ifdef __cplusplus
-}
-#endif // __cplusplus
-
-#endif // !MEM_LIBC_H

mem/include/util/mem_utils.h

@@ -1,16 +0,0 @@
-#ifndef MEM_UTILS_H
-#define MEM_UTILS_H
-
-#include "aliases.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif // __cplusplus
-
-void *wapp_mem_util_align_forward(void *ptr, u64 alignment);
-
-#ifdef __cplusplus
-}
-#endif // __cplusplus
-
-#endif // !MEM_UTILS_H

mem/src/allocator/mem_allocator.c

@@ -1,45 +0,0 @@
-#include "mem_allocator.h"
-#include <stdlib.h>
-
-void *wapp_mem_allocator_alloc(const Allocator *allocator, u64 size) {
-  if (!allocator || !(allocator->alloc)) {
-    return NULL;
-  }
-
-  return allocator->alloc(size, allocator->obj);
-}
-
-void *wapp_mem_allocator_alloc_aligned(const Allocator *allocator, u64 size,
-                                       u64 alignment) {
-  if (!allocator || !(allocator->alloc_aligned)) {
-    return NULL;
-  }
-
-  return allocator->alloc_aligned(size, alignment, allocator->obj);
-}
-
-void *wapp_mem_allocator_realloc(const Allocator *allocator, void *ptr,
-                                 u64 size) {
-  if (!allocator || !(allocator->realloc)) {
-    return NULL;
-  }
-
-  return allocator->realloc(ptr, size, allocator->obj);
-}
-
-void *wapp_mem_allocator_realloc_aligned(const Allocator *allocator, void *ptr,
-                                         u64 size, u64 alignment) {
-  if (!allocator || !(allocator->realloc_aligned)) {
-    return NULL;
-  }
-
-  return allocator->realloc_aligned(ptr, size, alignment, allocator->obj);
-}
-
-void wapp_mem_allocator_free(const Allocator *allocator, void **ptr) {
-  if (!allocator || !(allocator->free)) {
-    return;
-  }
-
-  allocator->free(ptr, allocator->obj);
-}

mem/src/arena/mem_arena.c

@@ -1,406 +0,0 @@
-#include "mem_arena.h"
-#include "aliases.h"
-#include "mem_allocator.h"
-#include "mem_utils.h"
-#include <math.h>
-#include <stdbool.h>
-#include <stdlib.h>
-#include <string.h>
-
-#ifndef DEFAULT_ALIGNMENT
-// Why 2 * sizeof(void *) instead of sizeof(void *)
-// https://handmade.network/forums/t/6860-alignment_arena_allocator
-#define DEFAULT_ALIGNMENT (2 * sizeof(void *))
-#endif /* ifndef DEFAULT_ALIGNMENT */
-
-#define HDR_MAGIC_BYTE_COUNT 8
-#define HDR_MAGIC                                                              \
-  { 0x57, 0x41, 0x41, 0x52, 0x4e, 0x48, 0x44, 0x52 }
-#define MAX_HDR_SEARCH_LENGTH 256
-
-#define ARENA_MINIMUM_CAPACITY 1024
-
-typedef struct arena_alloc_hdr ArenaAllocHDR;
-struct arena_alloc_hdr {
-  u8 magic[HDR_MAGIC_BYTE_COUNT];
-  u64 alloc_size;
-  u64 alignment;
-  u8 *alloc_start;
-};
-
-typedef struct base_arena BaseArena;
-struct base_arena {
-  u8 *buf;
-  u8 *offset;
-  u64 capacity;
-  BaseArena *prev;
-  BaseArena *next;
-};
-
-struct growing_arena {
-  BaseArena *active_arena;
-  u64 count;
-  u64 initial_capacity;
-};
-
-internal BaseArena *find_arena_from_pointer(const Arena *arena, void *ptr);
-
-internal bool base_arena_init(BaseArena *arena, u64 capacity);
-internal void *base_arena_alloc_aligned(BaseArena *arena, u64 size,
-                                        u64 alignment);
-internal void base_arena_clear(BaseArena *arena);
-internal void base_arena_free(BaseArena *arena);
-internal ArenaAllocHDR *find_alloc_header(BaseArena *arena, void *alloc_ptr);
-
-internal void *mem_arena_alloc(u64 size, void *alloc_obj);
-internal void *mem_arena_alloc_aligned(u64 size, u64 alignment,
-                                       void *alloc_obj);
-internal void *mem_arena_realloc(void *ptr, u64 size, void *alloc_obj);
-internal void *mem_arena_realloc_aligned(void *ptr, u64 size, u64 alignment,
-                                         void *alloc_obj);
-
-// PUBLIC API
-
-Allocator wapp_mem_arena_allocator(const Arena *arena) {
-  return (Allocator){
-      .obj = (void *)arena,
-      .alloc = mem_arena_alloc,
-      .alloc_aligned = mem_arena_alloc_aligned,
-      .realloc = mem_arena_realloc,
-      .realloc_aligned = mem_arena_realloc_aligned,
-      .free = NULL,
-  };
-}
-
-bool wapp_mem_arena_init(Arena **arena, u64 base_capacity) {
-  if (!arena || *arena || base_capacity == 0) {
-    return false;
-  }
-
-  *arena = (Arena *)calloc(1, sizeof(Arena));
-  Arena *arena_ptr = *arena;
-  if (!arena_ptr) {
-    return false;
-  }
-
-  arena_ptr->active_arena = (BaseArena *)calloc(1, sizeof(BaseArena));
-  if (!(arena_ptr->active_arena)) {
-    wapp_mem_arena_free(arena);
-    return false;
-  }
-
-  if (!base_arena_init(arena_ptr->active_arena, base_capacity)) {
-    wapp_mem_arena_free(arena);
-    return false;
-  }
-
-  arena_ptr->count = 1;
-  arena_ptr->initial_capacity = base_capacity;
-
-  return true;
-}
-
-void *wapp_mem_arena_alloc(Arena *arena, u64 size) {
-  return wapp_mem_arena_alloc_aligned(arena, size, DEFAULT_ALIGNMENT);
-}
-
-void *wapp_mem_arena_alloc_aligned(Arena *arena, u64 size, u64 alignment) {
-  if (!arena || !(arena->active_arena)) {
-    return NULL;
-  }
-
-  void *output = base_arena_alloc_aligned(arena->active_arena, size, alignment);
-  if (!output) {
-    if (arena->active_arena->next) {
-      arena->active_arena = arena->active_arena->next;
-    } else {
-      arena->active_arena->next = (BaseArena *)calloc(1, sizeof(BaseArena));
-      if (!(arena->active_arena->next)) {
-        return NULL;
-      }
-
-      if (!base_arena_init(arena->active_arena->next,
-                           arena->initial_capacity)) {
-        free(arena->active_arena->next);
-        return NULL;
-      }
-
-      arena->active_arena->next->prev = arena->active_arena;
-      arena->active_arena = arena->active_arena->next;
-
-      ++(arena->count);
-    }
-
-    output = base_arena_alloc_aligned(arena->active_arena, size, alignment);
-    if (!output) {
-      return NULL;
-    }
-  }
-
-  memset(output, 0, size);
-
-  return output;
-}
-
-void *wapp_mem_arena_realloc(Arena *arena, void *ptr, u64 size) {
-  return wapp_mem_arena_realloc_aligned(arena, ptr, size, DEFAULT_ALIGNMENT);
-}
-
-void *wapp_mem_arena_realloc_aligned(Arena *arena, void *ptr, u64 size,
-                                     u64 alignment) {
-  if (!arena) {
-    return NULL;
-  }
-
-  BaseArena *base_arena = find_arena_from_pointer(arena, ptr);
-  if (!base_arena) {
-    return NULL;
-  }
-
-  ArenaAllocHDR *header = find_alloc_header(base_arena, ptr);
-  if (!header) {
-    return NULL;
-  }
-
-  if (header->alloc_start + header->alloc_size == base_arena->offset) {
-    // Avoid allocating new pointer and copying memory if pointer is at the end
-    // of the arena
-    i64 diff = size - header->alloc_size;
-
-    u8 *new_offset = base_arena->offset + diff;
-
-    u8 *clear_start = diff < 0 ? new_offset : base_arena->offset;
-    memset(clear_start, 0, llabs(diff));
-
-    header->alloc_size = size;
-    base_arena->offset = new_offset;
-
-    return header->alloc_start;
-  }
-
-  void *new_alloc = wapp_mem_arena_alloc_aligned(arena, size, alignment);
-  if (!new_alloc) {
-    return NULL;
-  }
-
-  u64 to_copy = size < header->alloc_size ? size : header->alloc_size;
-
-  memcpy(new_alloc, ptr, to_copy);
-
-  return new_alloc;
-}
-
-void wapp_mem_arena_clear(Arena *arena) {
-  if (!arena) {
-    return;
-  }
-
-  BaseArena *last_active = NULL;
-  while (arena->active_arena) {
-    base_arena_clear(arena->active_arena);
-
-    last_active = arena->active_arena;
-
-    arena->active_arena = arena->active_arena->prev;
-  }
-
-  arena->active_arena = last_active;
-}
-
-void wapp_mem_arena_free(Arena **arena) {
-  if (!arena) {
-    return;
-  }
-
-  Arena *arena_ptr = *arena;
-  if (!arena_ptr) {
-    return;
-  }
-
-  BaseArena *current;
-  BaseArena *next;
-  BaseArena *prev;
-
-  current = arena_ptr->active_arena->next;
-  while (current) {
-    next = current->next;
-
-    base_arena_free(current);
-    free(current);
-
-    current = next;
-  }
-
-  current = arena_ptr->active_arena->prev;
-  while (current) {
-    prev = current->prev;
-
-    base_arena_free(current);
-    free(current);
-
-    current = prev;
-  }
-
-  base_arena_free(arena_ptr->active_arena);
-
-  free(arena_ptr->active_arena);
-  arena_ptr->active_arena = NULL;
-
-  arena_ptr->count = 0;
-  arena_ptr->initial_capacity = 0;
-
-  free(*arena);
-  *arena = NULL;
-}
-
-// INTERNAL FUNCTIONS
-
-internal BaseArena *find_arena_from_pointer(const Arena *arena, void *ptr) {
-  if (!arena || !ptr) {
-    return NULL;
-  }
-
-  // Ensure pointer is not out of bounds
-  u8 *alloc = (u8 *)ptr;
-  BaseArena *active = arena->active_arena;
-
-  if (alloc > active->buf + arena->initial_capacity) {
-    return NULL;
-  }
-
-  for (u64 i = 0; i < arena->count; ++i) {
-    if (alloc >= active->buf && alloc < active->buf + arena->initial_capacity) {
-      return (BaseArena *)active;
-    }
-
-    active = active->prev;
-  }
-
-  return NULL;
-}
-
-internal bool base_arena_init(BaseArena *arena, u64 capacity) {
-  if (!arena || arena->buf || capacity == 0) {
-    return false;
-  }
-
-  u64 arena_capacity =
-      capacity >= ARENA_MINIMUM_CAPACITY ? capacity : ARENA_MINIMUM_CAPACITY;
-
-  arena->buf = (u8 *)calloc(arena_capacity, sizeof(u8));
-  if (!(arena->buf)) {
-    return false;
-  }
-
-  arena->capacity = arena_capacity;
-  arena->offset = arena->buf;
-  arena->prev = arena->next = NULL;
-
-  return true;
-}
-
-internal void *base_arena_alloc_aligned(BaseArena *arena, u64 size,
-                                        u64 alignment) {
-  if (!arena) {
-    return NULL;
-  }
-
-  u8 *start_offset = arena->offset;
-  u8 *alloc_start = arena->offset + sizeof(ArenaAllocHDR);
-
-  u8 *output = wapp_mem_util_align_forward((void *)alloc_start, alignment);
-  if (output + size >= arena->buf + arena->capacity) {
-    return NULL;
-  }
-
-  ArenaAllocHDR *header = (ArenaAllocHDR *)start_offset;
-  *header = (ArenaAllocHDR){
-      .magic = HDR_MAGIC,
-      .alloc_size = size,
-      .alignment = alignment,
-      .alloc_start = output,
-  };
-
-  arena->offset = output + size;
-
-  return (void *)output;
-}
-
-internal void base_arena_clear(BaseArena *arena) {
-  if (!arena) {
-    return;
-  }
-
-  memset(arena->buf, 0, arena->offset - arena->buf);
-  arena->offset = arena->buf;
-}
-
-internal void base_arena_free(BaseArena *arena) {
-  if (!arena) {
-    return;
-  }
-
-  if (arena->buf) {
-    free(arena->buf);
-  }
-
-  arena->buf = arena->offset = NULL;
-  arena->capacity = 0;
-  arena->prev = arena->next = NULL;
-}
-
-internal ArenaAllocHDR *find_alloc_header(BaseArena *arena, void *alloc_ptr) {
-  persistent const u8 magic[HDR_MAGIC_BYTE_COUNT] = HDR_MAGIC;
-
-  u8 *current = (u8 *)alloc_ptr;
-
-  u8 *max_search_end = current - MAX_HDR_SEARCH_LENGTH;
-  u8 *arena_buf_start = arena->buf;
-
-  u8 *search_end =
-      max_search_end > arena_buf_start ? max_search_end : arena_buf_start;
-
-  bool match;
-  for (; current >= search_end; --current) {
-    match = true;
-
-    for (u64 i = 0; i < HDR_MAGIC_BYTE_COUNT; ++i) {
-      if (current[i] != magic[i]) {
-        match = false;
-        break;
-      }
-    }
-
-    if (match) {
-      return (ArenaAllocHDR *)current;
-    }
-  }
-
-  return NULL;
-}
-
-internal void *mem_arena_alloc(u64 size, void *alloc_obj) {
-  Arena *arena = (Arena *)alloc_obj;
-
-  return wapp_mem_arena_alloc(arena, size);
-}
-
-internal void *mem_arena_alloc_aligned(u64 size, u64 alignment,
-                                       void *alloc_obj) {
-  Arena *arena = (Arena *)alloc_obj;
-
-  return wapp_mem_arena_alloc_aligned(arena, size, alignment);
-}
-
-internal void *mem_arena_realloc(void *ptr, u64 size, void *alloc_obj) {
-  Arena *arena = (Arena *)alloc_obj;
-
-  return wapp_mem_arena_realloc(arena, ptr, size);
-}
-
-internal void *mem_arena_realloc_aligned(void *ptr, u64 size, u64 alignment,
-                                         void *alloc_obj) {
-  Arena *arena = (Arena *)alloc_obj;
-
-  return wapp_mem_arena_realloc_aligned(arena, ptr, size, alignment);
-}

mem/src/ctx/mem_ctx.c

@@ -1,106 +0,0 @@
-#include "mem_ctx.h"
-#include "aliases.h"
-#include "mem_arena.h"
-#include <assert.h>
-#include <stdlib.h>
-
-typedef struct mem_ctx MemCTX;
-struct mem_ctx {
-  Arena *main;
-  Arena *temp;
-  bool main_initialised;
-  bool temp_initialised;
-};
-
-internal MemCTX g_context = {0};
-
-internal Arena *get_arena(CTXDestBuffer buffer);
-
-Allocator wapp_mem_ctx_allocator(CTXDestBuffer buffer) {
-  Arena *arena = get_arena(buffer);
-  return wapp_mem_arena_allocator(arena);
-}
-
-void wapp_mem_ctx_init(u64 main_buf_capacity, u64 temp_buf_capacity) {
-  g_context.main_initialised =
-      wapp_mem_arena_init(&g_context.main, main_buf_capacity);
-  g_context.temp_initialised =
-      wapp_mem_arena_init(&g_context.temp, temp_buf_capacity);
-}
-
-void *wapp_mem_ctx_alloc(CTXDestBuffer buffer, u64 size) {
-  Arena *arena = get_arena(buffer);
-  if (!arena) {
-    return NULL;
-  }
-
-  return wapp_mem_arena_alloc(arena, size);
-}
-
-void *wapp_mem_ctx_alloc_aligned(CTXDestBuffer buffer, u64 size,
-                                 u64 alignment) {
-  Arena *arena = get_arena(buffer);
-  if (!arena) {
-    return NULL;
-  }
-
-  return wapp_mem_arena_alloc_aligned(arena, size, alignment);
-}
-
-void *wapp_mem_ctx_realloc(CTXDestBuffer buffer, void *ptr, u64 size) {
-  Arena *arena = get_arena(buffer);
-  if (!arena) {
-    return NULL;
-  }
-
-  return wapp_mem_arena_realloc(arena, ptr, size);
-}
-
-void *wapp_mem_ctx_realloc_aligned(CTXDestBuffer buffer, void *ptr, u64 size,
-                                   u64 alignment) {
-  Arena *arena = get_arena(buffer);
-  if (!arena) {
-    return NULL;
-  }
-
-  return wapp_mem_arena_realloc_aligned(arena, ptr, size, alignment);
-}
-
-void wapp_mem_ctx_clear(CTXDestBuffer buffer) {
-  Arena *arena = get_arena(buffer);
-  if (!arena) {
-    return;
-  }
-
-  wapp_mem_arena_clear(arena);
-}
-
-void wapp_mem_ctx_free(void) {
-  wapp_mem_arena_free(&(g_context.main));
-  g_context.main_initialised = false;
-
-  wapp_mem_arena_free(&(g_context.temp));
-  g_context.temp_initialised = false;
-}
-
-internal Arena *get_arena(CTXDestBuffer buffer) {
-  Arena *output = NULL;
-
-  switch (buffer) {
-  case CTX_DEST_BUFFER_MAIN:
-    if (g_context.main_initialised) {
-      output = g_context.main;
-    }
-    break;
-  case CTX_DEST_BUFFER_TEMP:
-    if (g_context.temp_initialised) {
-      output = g_context.temp;
-    }
-    break;
-  default:
-    assert(false && "Not all context destination buffers are handled");
-    break;
-  }
-
-  return output;
-}

mem/src/libc/mem_libc.c

@@ -1,48 +0,0 @@
-#include "mem_libc.h"
-#include "aliases.h"
-#include "mem_allocator.h"
-#include <stdlib.h>
-#include <string.h>
-
-internal void *mem_libc_alloc(u64 size, void *alloc_obj);
-internal void *mem_libc_alloc_aligned(u64 size, u64 alignment, void *alloc_obj);
-internal void *mem_libc_realloc(void *ptr, u64 size, void *alloc_obj);
-internal void mem_libc_free(void **ptr, void *alloc_obj);
-
-Allocator wapp_mem_libc_allocator(void) {
-  return (Allocator){
-      .obj = NULL,
-      .alloc = mem_libc_alloc,
-      .alloc_aligned = mem_libc_alloc_aligned,
-      .realloc = mem_libc_realloc,
-      .realloc_aligned = NULL,
-      .free = mem_libc_free,
-  };
-}
-
-internal void *mem_libc_alloc(u64 size, void *alloc_obj) {
-  return calloc(1, size);
-}
-
-internal void *mem_libc_alloc_aligned(u64 size, u64 alignment,
-                                      void *alloc_obj) {
-  void *output = aligned_alloc(alignment, size);
-  if (output) {
-    memset(output, 0, size);
-  }
-
-  return output;
-}
-
-internal void *mem_libc_realloc(void *ptr, u64 size, void *alloc_obj) {
-  return realloc(ptr, size);
-}
-
-internal void mem_libc_free(void **ptr, void *alloc_obj) {
-  if (!ptr || !(*ptr)) {
-    return;
-  }
-
-  free(*ptr);
-  *ptr = NULL;
-}

mem/src/util/mem_utils.c

@@ -1,28 +0,0 @@
-#include "mem_utils.h"
-#include "aliases.h"
-#include <assert.h>
-#include <stdbool.h>
-#include <stdlib.h>
-
-internal bool is_power_of_two(u64 num) { return (num & (num - 1)) == 0; }
-
-void *wapp_mem_util_align_forward(void *ptr, u64 alignment) {
-  if (!ptr) {
-    return NULL;
-  }
-
-  assert(is_power_of_two(alignment));
-
-  uptr p = (uptr)ptr;
-  uptr align = (uptr)alignment;
-
-  // Similar to p % align, but it's a faster implementation that works fine
-  // because align is guaranteed to be a power of 2
-  uptr modulo = p & (align - 1);
-
-  if (modulo != 0) {
-    p += align - modulo;
-  }
-
-  return (void *)p;
-}

src/mem/arena/mem_arena.c

@@ -0,0 +1,113 @@
+#include "mem_arena.h"
+#include "aliases.h"
+#include "mem_utils.h"
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifndef DEFAULT_ALIGNMENT
+// Why 2 * sizeof(void *) instead of sizeof(void *)
+// https://handmade.network/forums/t/6860-alignment_arena_allocator
+#define DEFAULT_ALIGNMENT (2 * sizeof(void *))
+#endif /* ifndef DEFAULT_ALIGNMENT */
+
+#define ARENA_MINIMUM_CAPACITY 1024
+
+struct arena {
+  u8 *buf;
+  u8 *offset;
+  u64 capacity;
+  bool committed;
+};
+
+// PUBLIC API
+
+bool wapp_mem_arena_init(Arena **arena, u64 base_capacity, MemAllocFlags flags,
+                         bool zero_buffer) {
+  if (!arena || *arena || base_capacity == 0) {
+    return false;
+  }
+
+  *arena = (Arena *)calloc(1, sizeof(Arena));
+  Arena *arena_ptr = *arena;
+  if (!arena_ptr) {
+    return false;
+  }
+
+  u64 arena_capacity = base_capacity >= ARENA_MINIMUM_CAPACITY
+                           ? base_capacity
+                           : ARENA_MINIMUM_CAPACITY;
+
+  arena_ptr->buf = (u8 *)wapp_mem_util_alloc(
+      NULL, arena_capacity, WAPP_MEM_ACCESS_READ_WRITE, flags,
+      zero_buffer ? WAPP_MEM_INIT_INITIALISED : WAPP_MEM_INIT_UNINITIALISED);
+
+  if (!(arena_ptr->buf)) {
+    wapp_mem_arena_destroy(arena);
+    return false;
+  }
+
+  arena_ptr->capacity = arena_capacity;
+  arena_ptr->offset = arena_ptr->buf;
+  arena_ptr->committed =
+      (flags & WAPP_MEM_ALLOC_COMMIT) == WAPP_MEM_ALLOC_COMMIT;
+
+  return true;
+}
+
+void *wapp_mem_arena_alloc(Arena *arena, u64 size) {
+  return wapp_mem_arena_alloc_aligned(arena, size, DEFAULT_ALIGNMENT);
+}
+
+void *wapp_mem_arena_alloc_aligned(Arena *arena, u64 size, u64 alignment) {
+  if (!arena) {
+    return NULL;
+  }
+
+  u8 *alloc_start = arena->offset;
+
+  u8 *output = wapp_mem_util_align_forward((void *)alloc_start, alignment);
+  if (output + size >= arena->buf + arena->capacity) {
+    return NULL;
+  }
+
+  arena->offset = output + size;
+
+#ifdef WAPP_PLATFORM_WINDOWS
+  if (!(arena->committed)) {
+    output = (u8 *)wapp_mem_util_alloc(output, size, WAPP_MEM_ACCESS_READ_WRITE,
+                                       WAPP_MEM_ALLOC_COMMIT,
+                                       WAPP_MEM_INIT_UNINITIALISED);
+  }
+#endif // ifdef WAPP_PLATFORM_WINDOWS
+
+  memset(output, 0, size);
+
+  return (void *)output;
+}
+
+void wapp_mem_arena_clear(Arena *arena) {
+  if (!arena) {
+    return;
+  }
+
+  memset(arena->buf, 0, arena->offset - arena->buf);
+  arena->offset = arena->buf;
+}
+
+void wapp_mem_arena_destroy(Arena **arena) {
+  if (!arena) {
+    return;
+  }
+
+  Arena *arena_ptr = *arena;
+  if (arena_ptr->buf) {
+    wapp_mem_util_free(arena_ptr->buf, arena_ptr->capacity);
+  }
+
+  arena_ptr->buf = arena_ptr->offset = NULL;
+  arena_ptr->capacity = 0;
+
+  free(*arena);
+  *arena = NULL;
+}

src/mem/arena/mem_arena.h

@@ -0,0 +1,37 @@
+#ifndef MEM_ARENA_H
+#define MEM_ARENA_H
+
+#include "aliases.h"
+#include "mem_utils.h"
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+typedef struct arena Arena;
+
+#define wapp_mem_arena_init_default(arena_dptr, base_capacity)                 \
+  (wapp_mem_arena_init(arena_dptr, base_capacity, WAPP_MEM_ALLOC_RESERVE,      \
+                       false))
+#define wapp_mem_arena_init_commit(arena_dptr, base_capacity)                  \
+  (wapp_mem_arena_init(arena_dptr, base_capacity,                              \
+                       WAPP_MEM_ALLOC_RESERVE | WAPP_MEM_ALLOC_COMMIT, false))
+#define wapp_mem_arena_init_zero(arena_dptr, base_capacity)                    \
+  (wapp_mem_arena_init(arena_dptr, base_capacity, WAPP_MEM_ALLOC_RESERVE, true))
+#define wapp_mem_arena_init_commit_and_zero(arena_dptr, base_capacity)         \
+  (wapp_mem_arena_init(arena_dptr, base_capacity,                              \
+                       WAPP_MEM_ALLOC_RESERVE | WAPP_MEM_ALLOC_COMMIT, true))
+
+bool wapp_mem_arena_init(Arena **arena, u64 base_capacity, MemAllocFlags flags,
+                         bool zero_buffer);
+void *wapp_mem_arena_alloc(Arena *arena, u64 size);
+void *wapp_mem_arena_alloc_aligned(Arena *arena, u64 size, u64 alignment);
+void wapp_mem_arena_clear(Arena *arena);
+void wapp_mem_arena_destroy(Arena **arena);
+
+#ifdef __cplusplus
+}
+#endif // __cplusplus
+
+#endif // !MEM_ARENA_H

src/mem/util/mem_utils.c

@@ -0,0 +1,114 @@
+#include "mem_utils.h"
+#include "aliases.h"
+#include "platform.h"
+#include <assert.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if defined(WAPP_PLATFORM_WINDOWS)
+#include <Windows.h>
+#include <memoryapi.h>
+
+internal const i32 access_types[] = {
+    [WAPP_MEM_ACCESS_NONE] = PAGE_NOACCESS,
+    [WAPP_MEM_ACCESS_READ_ONLY] = PAGE_READONLY,
+    [WAPP_MEM_ACCESS_EXEC_ONLY] = PAGE_EXECUTE,
+    [WAPP_MEM_ACCESS_READ_WRITE] = PAGE_READWRITE,
+    [WAPP_MEM_ACCESS_READ_EXEC] = PAGE_EXECUTE_READ,
+    [WAPP_MEM_ACCESS_READ_WRITE_EXEC] = PAGE_EXECUTE_READWRITE,
+};
+
+internal inline void *alloc_windows(void *addr, u64 size, MemAccess access,
+                                    MemAllocFlags flags);
+#elif defined(WAPP_PLATFORM_POSIX)
+#include <sys/mman.h>
+
+internal const i32 access_types[] = {
+    [WAPP_MEM_ACCESS_NONE] = PROT_NONE,
+    [WAPP_MEM_ACCESS_READ_ONLY] = PROT_READ,
+    [WAPP_MEM_ACCESS_EXEC_ONLY] = PROT_EXEC,
+    [WAPP_MEM_ACCESS_READ_WRITE] = PROT_READ | PROT_WRITE,
+    [WAPP_MEM_ACCESS_READ_EXEC] = PROT_READ | PROT_EXEC,
+    [WAPP_MEM_ACCESS_READ_WRITE_EXEC] = PROT_READ | PROT_WRITE | PROT_EXEC,
+};
+
+internal inline void *alloc_posix(void *addr, u64 size, MemAccess access,
+                                  MemAllocFlags flags);
+#else
+#error "Unrecognised platform"
+#endif
+
+internal bool is_power_of_two(u64 num) { return (num & (num - 1)) == 0; }
+
+void *wapp_mem_util_align_forward(void *ptr, u64 alignment) {
+  if (!ptr) {
+    return NULL;
+  }
+
+  assert(is_power_of_two(alignment));
+
+  uptr p = (uptr)ptr;
+  uptr align = (uptr)alignment;
+
+  // Similar to p % align, but it's a faster implementation that works fine
+  // because align is guaranteed to be a power of 2
+  uptr modulo = p & (align - 1);
+
+  if (modulo != 0) {
+    p += align - modulo;
+  }
+
+  return (void *)p;
+}
+
+void *wapp_mem_util_alloc(void *addr, u64 size, MemAccess access,
+                          MemAllocFlags flags, MemInitType type) {
+#if defined(WAPP_PLATFORM_WINDOWS)
+  // Ensure memory is committed if it's meant to be initialised
+  if (type == WAPP_MEM_INIT_INITIALISED) {
+    flags |= WAPP_MEM_ALLOC_COMMIT;
+  }
+
+  void *output = alloc_windows(addr, size, access, flags);
+#elif defined(WAPP_PLATFORM_POSIX)
+  void *output = alloc_posix(addr, size, access, flags);
+#else
+  return NULL;
+#endif
+
+  if (type == WAPP_MEM_INIT_INITIALISED) {
+    memset(output, 0, size);
+  }
+
+  return output;
+}
+
+void wapp_mem_util_free(void *ptr, u64 size) {
+#if defined(WAPP_PLATFORM_WINDOWS)
+  VirtualFree(ptr, size, MEM_RELEASE);
+#elif defined(WAPP_PLATFORM_POSIX)
+  munmap(ptr, size);
+#endif
+}
+
+#ifdef WAPP_PLATFORM_WINDOWS
+internal inline void *alloc_windows(void *addr, u64 size, MemAccess access,
+                                    MemAllocFlags flags) {
+  return VirtualAlloc2(addr, NULL, (SIZE_T)size, flags, access_types[access]);
+}
+#endif
+
+#if defined(WAPP_PLATFORM_POSIX)
+internal inline void *alloc_posix(void *addr, u64 size, MemAccess access,
+                                  MemAllocFlags flags) {
+  i32 alloc_flags = flags | MAP_ANON | MAP_PRIVATE;
+
+#if defined(WAPP_PLATFORM_LINUX) || defined(WAPP_PLATFORM_GNU) ||              \
+    defined(WAPP_PLATFORM_NET_BSD)
+  alloc_flags |= MAP_NORESERVE;
+#endif
+
+  return mmap(addr, size, access_types[access], alloc_flags, -1, 0);
+}
+#endif

src/mem/util/mem_utils.h

@@ -0,0 +1,60 @@
+#ifndef MEM_UTILS_H
+#define MEM_UTILS_H
+
+#include "aliases.h"
+#include "platform.h"
+
+#if defined(WAPP_PLATFORM_WINDOWS)
+#include <Windows.h>
+#include <memoryapi.h>
+#elif defined(WAPP_PLATFORM_POSIX)
+#include <sys/mman.h>
+#else
+#error "Unrecognised platform"
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+typedef enum mem_access {
+  WAPP_MEM_ACCESS_NONE,
+  WAPP_MEM_ACCESS_READ_ONLY,
+  WAPP_MEM_ACCESS_EXEC_ONLY,
+  WAPP_MEM_ACCESS_READ_WRITE,
+  WAPP_MEM_ACCESS_READ_EXEC,
+  WAPP_MEM_ACCESS_READ_WRITE_EXEC,
+} MemAccess;
+
+typedef enum mem_alloc_flags {
+#if defined(WAPP_PLATFORM_WINDOWS)
+  WAPP_MEM_ALLOC_RESERVE = MEM_RESERVE,
+  WAPP_MEM_ALLOC_COMMIT = MEM_COMMIT,
+#elif defined(WAPP_PLATFORM_LINUX) || defined(WAPP_PLATFORM_GNU)
+  WAPP_MEM_ALLOC_RESERVE = 0,
+  WAPP_MEM_ALLOC_COMMIT = MAP_POPULATE,
+#elif defined(WAPP_PLATFORM_FREE_BSD)
+  WAPP_MEM_ALLOC_RESERVE = 0,
+  WAPP_MEM_ALLOC_COMMIT = MAP_PREFAULT_READ,
+#elif defined(WAPP_PLATFORM_BSD) || defined(WAPP_PLATFORM_UNIX) ||             \
+    defined(WAPP_PLATFORM_APPLE)
+  WAPP_MEM_ALLOC_RESERVE = 0,
+  WAPP_MEM_ALLOC_COMMIT = 0,
+#endif
+} MemAllocFlags;
+
+typedef enum mem_init_type {
+  WAPP_MEM_INIT_UNINITIALISED,
+  WAPP_MEM_INIT_INITIALISED,
+} MemInitType;
+
+void *wapp_mem_util_align_forward(void *ptr, u64 alignment);
+void *wapp_mem_util_alloc(void *addr, u64 size, MemAccess access,
+                          MemAllocFlags flags, MemInitType type);
+void wapp_mem_util_free(void *ptr, u64 size);
+
+#ifdef __cplusplus
+}
+#endif // __cplusplus
+
+#endif // !MEM_UTILS_H

src/platform/platform.h

@@ -0,0 +1,63 @@
+#ifndef PLATFORM_H
+#define PLATFORM_H
+
+// clang-format off
+#if defined(__ANDROID__)
+  #define WAPP_PLATFORM_ANDROID
+  #define WAPP_PLATFORM_POSIX
+#elif defined(__FreeBSD__)
+  #define WAPP_PLATFORM_FREE_BSD
+  #define WAPP_PLATFORM_BSD
+  #define WAPP_PLATFORM_POSIX
+#elif defined(__NetBSD__)
+  #define WAPP_PLATFORM_NET_BSD
+  #define WAPP_PLATFORM_BSD
+  #define WAPP_PLATFORM_POSIX
+#elif defined(__OpenBSD__)
+  #define WAPP_PLATFORM_OPEN_BSD
+  #define WAPP_PLATFORM_BSD
+  #define WAPP_PLATFORM_POSIX
+#elif defined(__DragonFly__)
+  #define WAPP_PLATFORM_DRAGON_FLY
+  #define WAPP_PLATFORM_BSD
+  #define WAPP_PLATFORM_POSIX
+#elif defined(__bsdi__)
+  #define WAPP_PLATFORM_BSD
+  #define WAPP_PLATFORM_POSIX
+#elif defined(__linux__) || defined(linux) || defined(__linux) || defined(__gnu_linux__)
+  #define WAPP_PLATFORM_LINUX
+  #define WAPP_PLATFORM_POSIX
+#elif defined(__GNU__) || defined(__gnu_hurd__)
+  #define WAPP_PLATFORM_GNU
+  #define WAPP_PLATFORM_POSIX
+#elif defined(__APPLE__) || defined(__MACH__)
+  #include <TargetConditionals.h>
+  #if TARGET_OS_IPHONE
+    #define WAPP_PLATFORM_IOS
+    #define WAPP_PLATFORM_APPLE
+    #define WAPP_PLATFORM_POSIX
+  #elif TARGET_OS_MAC
+    #define WAPP_PLATFORM_MACOS
+    #define WAPP_PLATFORM_APPLE
+    #define WAPP_PLATFORM_POSIX
+  #else
+    #error "Unrecognised Apple platform"
+  #endif
+#elif defined(_WIN64)
+  #define WAPP_PLATFORM_WINDOWS64
+  #define WAPP_PLATFORM_WINDOWS
+#elif defined(_WIN32)
+  #define WAPP_PLATFORM_WINDOWS32
+  #define WAPP_PLATFORM_WINDOWS
+#elif defined(__CYGWIN__)
+  #define WAPP_PLATFORM_CYGWIN
+  #define WAPP_PLATFORM_WINDOWS
+#elif defined(__unix__) || defined(__unix)
+  #define WAPP_PLATFORM_UNIX
+  #define WAPP_PLATFORM_POSIX
+#else
+  #error "Unrecognised platform"
+#endif
+// clang-format on
+
+#endif // !PLATFORM_H

src/strings/basic_strings/basic_strings.h

@@ -0,0 +1,34 @@
+#ifndef BASIC_STRING_H
+#define BASIC_STRING_H
+
+#include "aliases.h"
+#include <stdio.h>
+#include <string.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+typedef struct bstr BasicString;
+struct bstr {
+  u64 size;
+  const char *buf;
+};
+
+typedef struct strvw StringView;
+struct strvw {
+  const u64 size;
+  const char *buf;
+};
+
+#define new_string(STR)                                                        \
+  { .size = strlen(STR), .buf = STR }
+#define wapp_bstr_new(STR) ((BasicString)new_string(STR))
+#define wapp_strvw_new(STR) ((StringView)new_string(STR))
+#define wapp_string_print(STR) (printf("%.*s\n", (i32)STR.size, STR.buf))
+
+#ifdef __cplusplus
+}
+#endif // __cplusplus
+
+#endif // !BASIC_STRING_H

src/strings/dstr/dstr.c

@@ -1,7 +1,6 @@
 #include "dstr.h"
 #include "aliases.h"
-#include "mem_allocator.h"
+#include "mem_arena.h"
-#include "mem_libc.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -9,45 +8,42 @@
 // Use this scalar to allocate extra memory in order to avoid having to
 // constantly reallocate
 #define CAPACITY_SCALAR 8
+#define MINIMUM_DSTR_CAPACITY 1024
 
 struct dstr {
-  Allocator allocator;
   u64 capacity;
   u64 size;
   char buf[];
 };
 
-String *wapp_dstr_with_capacity(u64 capacity, const Allocator *allocator) {
+String *wapp_dstr_with_capacity(u64 capacity, Arena *arena) {
-  Allocator alloc;
+  if (!arena) {
-  if (allocator) {
+    return NULL;
-    alloc = *allocator;
-  } else {
-    alloc = wapp_mem_libc_allocator();
   }
 
   String *out =
-      (String *)wapp_mem_allocator_alloc(&alloc, sizeof(String) + capacity + 1);
+      (String *)wapp_mem_arena_alloc(arena, sizeof(String) + capacity + 1);
   if (!out) {
     return NULL;
   }
 
-  out->allocator = alloc;
   out->capacity = capacity;
   out->size = 0;
 
   return out;
 }
 
-String *wapp_dstr_from_string(const char *str, const Allocator *allocator) {
+String *wapp_dstr_from_string(const char *str, Arena *arena) {
-  if (!str) {
+  if (!str || !arena) {
     return NULL;
   }
 
   u64 length = strlen(str);
-
   u64 capacity = length * CAPACITY_SCALAR;
+  capacity =
+      capacity >= MINIMUM_DSTR_CAPACITY ? capacity : MINIMUM_DSTR_CAPACITY;
 
-  String *out = wapp_dstr_with_capacity(capacity, allocator);
+  String *out = wapp_dstr_with_capacity(capacity, arena);
   if (!out) {
     return NULL;
   }
@@ -58,55 +54,45 @@ String *wapp_dstr_from_string(const char *str, const Allocator *allocator) {
   return out;
 }
 
-void wapp_dstr_update(String **dst, const char *src) {
+StringUpdate wapp_dstr_update(String **dst, const char *src, Arena *arena) {
   if (!dst || !(*dst)) {
-    return;
+    return (StringUpdate){.updated = false, .str = *dst};
   }
 
   u64 length = strlen(src);
 
   String *str = *dst;
 
-  if (length < str->capacity) {
+  if (length >= str->capacity) {
+    if (!arena) {
+      return (StringUpdate){.updated = false, .str = *dst};
+    }
+
+    String *new_str = wapp_dstr_from_string(src, arena);
+    if (!new_str) {
+      return (StringUpdate){.updated = false, .str = *dst};
+    }
+
+    return (StringUpdate){.updated = true, .str = new_str};
+  }
+
   memset(str->buf, 0, str->capacity);
 
   str->size = length;
 
   strncpy(str->buf, src, length + 1);
-  } else {
-    u64 capacity = length * CAPACITY_SCALAR;
 
-    String *tmp = (String *)wapp_mem_allocator_realloc(
+  return (StringUpdate){.updated = true, .str = *dst};
-        &(str->allocator), *dst, sizeof(String) + capacity + 1);
-    if (!tmp) {
-      return;
-    }
-
-    tmp->capacity = capacity;
-    tmp->size = length;
-    strncpy(tmp->buf, src, length + 1);
-
-    *dst = tmp;
-  }
 }
 
-void wapp_dstr_free(String **str) {
+StringUpdate wapp_dstr_concat(String **dst, const char *src, Arena *arena) {
-  if (!str || !(*str)) {
-    return;
-  }
-
-  String *str_ptr = *str;
-  wapp_mem_allocator_free(&(str_ptr->allocator), (void **)str);
-}
-
-void wapp_dstr_concat(String **dst, const char *src) {
   if (!dst || !(*dst)) {
-    return;
+    return (StringUpdate){.updated = false, .str = *dst};
   }
 
   u64 src_length = strlen(src);
   if (src_length == 0) {
-    return;
+    return (StringUpdate){.updated = false, .str = *dst};
   }
 
   u64 new_length = (*dst)->size + src_length;
@@ -117,42 +103,7 @@ void wapp_dstr_concat(String **dst, const char *src) {
   strncpy(str, (*dst)->buf, (*dst)->size);
   strncat(str, src, new_length + 1 - (*dst)->size);
 
-  wapp_dstr_update(dst, str);
+  return wapp_dstr_update(dst, str, arena);
-}
-
-void wapp_dstr_append(String **dst, char c) {
-  if (!dst || !(*dst)) {
-    return;
-  }
-
-  u64 new_length = (*dst)->size + 1;
-
-  char str[new_length + 1];
-  memset(str, 0, new_length + 1);
-
-  strncpy(str, (*dst)->buf, (*dst)->size);
-  str[(*dst)->size] = c;
-
-  wapp_dstr_update(dst, str);
-}
-
-void wapp_dstr_resize(String **str) {
-  if (!str || !(*str)) {
-    return;
-  }
-
-  String *str_ptr = *str;
-  u64 capacity = (*str)->size;
-
-  String *tmp = (String *)wapp_mem_allocator_realloc(
-      &(str_ptr->allocator), *str, sizeof(String) + capacity + 1);
-  if (!tmp) {
-    return;
-  }
-
-  tmp->capacity = capacity;
-
-  *str = tmp;
 }
 
 void wapp_dstr_clear(String *str) {

src/strings/dstr/dstr.h

@@ -2,7 +2,8 @@
 #define DSTR_H
 
 #include "aliases.h"
-#include "mem_allocator.h"
+#include "mem_arena.h"
+#include <stdbool.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -10,13 +11,16 @@ extern "C" {
 
 typedef struct dstr String;
 
-String *wapp_dstr_with_capacity(u64 capacity, const Allocator *allocator);
+typedef struct string_update StringUpdate;
-String *wapp_dstr_from_string(const char *str, const Allocator *allocator);
+struct string_update {
-void wapp_dstr_update(String **dst, const char *src);
+  bool updated;
-void wapp_dstr_free(String **str);
+  String *str;
-void wapp_dstr_concat(String **dst, const char *src);
+};
-void wapp_dstr_append(String **dst, char c);
+
-void wapp_dstr_resize(String **str);
+String *wapp_dstr_with_capacity(u64 capacity, Arena *arena);
+String *wapp_dstr_from_string(const char *str, Arena *arena);
+StringUpdate wapp_dstr_update(String **dst, const char *src, Arena *arena);
+StringUpdate wapp_dstr_concat(String **dst, const char *src, Arena *arena);
 void wapp_dstr_clear(String *str);
 void wapp_dstr_print(const String *str);
 i64 wapp_dstr_find(const String *str, const char *substr);

src/termcolour/termcolour.h

@@ -0,0 +1,48 @@
+#ifndef TERM_COLOUR_H
+#define TERM_COLOUR_H
+
+#include "platform.h"
+
+// clang-format off
+#if defined(WAPP_PLATFORM_WINDOWS)
+  #define TERM_COLOUR_CLEAR ""
+  #define TERM_COLOUR_BOLD ""
+  #define TERM_COLOUR_FG_BLACK ""
+  #define TERM_COLOUR_FG_RED ""
+  #define TERM_COLOUR_FG_GREEN ""
+  #define TERM_COLOUR_FG_YELLOW ""
+  #define TERM_COLOUR_FG_BLUE ""
+  #define TERM_COLOUR_FG_MAGENTA ""
+  #define TERM_COLOUR_FG_CYAN ""
+  #define TERM_COLOUR_FG_WHITE ""
+  #define TERM_COLOUR_FG_BR_BLACK ""
+  #define TERM_COLOUR_FG_BR_RED ""
+  #define TERM_COLOUR_FG_BR_GREEN ""
+  #define TERM_COLOUR_FG_BR_YELLOW ""
+  #define TERM_COLOUR_FG_BR_BLUE ""
+  #define TERM_COLOUR_FG_BR_MAGENTA ""
+  #define TERM_COLOUR_FG_BR_CYAN ""
+  #define TERM_COLOUR_FG_BR_WHITE ""
+#elif defined(WAPP_PLATFORM_POSIX)
+  #define TERM_COLOUR_CLEAR "\033[0m"
+  #define TERM_COLOUR_BOLD "\033[1m"
+  #define TERM_COLOUR_FG_BLACK "\033[30m"
+  #define TERM_COLOUR_FG_RED "\033[31m"
+  #define TERM_COLOUR_FG_GREEN "\033[32m"
+  #define TERM_COLOUR_FG_YELLOW "\033[33m"
+  #define TERM_COLOUR_FG_BLUE "\033[34m"
+  #define TERM_COLOUR_FG_MAGENTA "\033[35m"
+  #define TERM_COLOUR_FG_CYAN "\033[36m"
+  #define TERM_COLOUR_FG_WHITE "\033[37m"
+  #define TERM_COLOUR_FG_BR_BLACK "\033[90m"
+  #define TERM_COLOUR_FG_BR_RED "\033[91m"
+  #define TERM_COLOUR_FG_BR_GREEN "\033[92m"
+  #define TERM_COLOUR_FG_BR_YELLOW "\033[93m"
+  #define TERM_COLOUR_FG_BR_BLUE "\033[94m"
+  #define TERM_COLOUR_FG_BR_MAGENTA "\033[95m"
+  #define TERM_COLOUR_FG_BR_CYAN "\033[96m"
+  #define TERM_COLOUR_FG_BR_WHITE "\033[97m"
+#endif
+// clang-format on
+
+#endif // !TERM_COLOUR_H

src/tester/tester.c

@@ -0,0 +1,48 @@
+#include "tester.h"
+#include "aliases.h"
+#include "termcolour/termcolour.h"
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+internal void print_test_result(TestFuncResult result);
+
+void run_tests(TestFunc *func1, ...) {
+  printf("\n");
+
+  print_test_result(func1());
+
+  va_list args;
+  va_start(args, func1);
+
+  TestFunc *func = NULL;
+
+  while ((func = va_arg(args, TestFunc *))) {
+    TestFuncResult result = func();
+    print_test_result(result);
+
+    if (!result.passed) {
+      exit(EXIT_FAILURE);
+    }
+  }
+
+  va_end(args);
+
+  printf("\n");
+}
+
+internal void print_test_result(TestFuncResult result) {
+  const char *colour;
+  const char *result_text;
+
+  if (result.passed) {
+    colour = TERM_COLOUR_FG_BR_GREEN;
+    result_text = "PASSED";
+  } else {
+    colour = TERM_COLOUR_FG_BR_RED;
+    result_text = "FAILED";
+  }
+
+  printf("[%s%s%s%s] %s\n", colour, TERM_COLOUR_BOLD, result_text,
+         TERM_COLOUR_CLEAR, result.name);
+}

src/tester/tester.h

@@ -0,0 +1,28 @@
+#ifndef TESTER_H
+#define TESTER_H
+
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+#define wapp_tester_result(test_passed)                                        \
+  ((TestFuncResult){.name = __func__, .passed = test_passed})
+#define wapp_tester_run_tests(...) run_tests(__VA_ARGS__, NULL)
+
+typedef struct test_func_result TestFuncResult;
+struct test_func_result {
+  const char *name;
+  bool passed;
+};
+
+typedef TestFuncResult(TestFunc)(void);
+
+void run_tests(TestFunc *func1, ...);
+
+#ifdef __cplusplus
+}
+#endif // __cplusplus
+
+#endif // !TESTER_H

tests/arena/test_arena.c

@@ -0,0 +1,69 @@
+#include "test_arena.h"
+#include "aliases.h"
+#include "mem_arena.h"
+#include "tester.h"
+#include <stdbool.h>
+#include <stdlib.h>
+
+#define ARENA_CAPACITY 1024
+
+internal Arena *arena = NULL;
+internal u64 count = 20;
+internal i32 *array = NULL;
+
+TestFuncResult test_arena_init(void) {
+  bool result = wapp_mem_arena_init_default(&arena, ARENA_CAPACITY);
+
+  return wapp_tester_result(result);
+}
+
+TestFuncResult test_arena_init_succeeds_when_reserving_very_large_size(void) {
+  Arena *large_arena = NULL;
+  u64 capacity = 512ull * 1024ull * 1024ull * 1024ull;
+  bool result =
+      wapp_mem_arena_init(&large_arena, capacity, WAPP_MEM_ALLOC_RESERVE, false);
+	if (result) {
+		wapp_mem_arena_destroy(&large_arena);
+	}
+
+	return wapp_tester_result(result);
+}
+
+TestFuncResult test_arena_alloc_succeeds_when_within_capacity(void) {
+  array = wapp_mem_arena_alloc(arena, count * sizeof(i32));
+  bool result = array != NULL;
+
+  for (u64 i = 0; i < count; ++i) {
+    array[i] = i * 10;
+  }
+
+  return wapp_tester_result(result);
+}
+
+TestFuncResult test_arena_alloc_fails_when_over_capacity(void) {
+  u8 *bytes = wapp_mem_arena_alloc(arena, ARENA_CAPACITY * 2);
+  bool result = bytes == NULL;
+
+  return wapp_tester_result(result);
+}
+
+TestFuncResult test_arena_clear(void) {
+  wapp_mem_arena_clear(arena);
+  bool result = true;
+
+  for (u64 i = 0; i < count; ++i) {
+    if (array[i] != 0) {
+      result = false;
+      break;
+    }
+  }
+
+  return wapp_tester_result(result);
+}
+
+TestFuncResult test_arena_destroy(void) {
+  wapp_mem_arena_destroy(&arena);
+  bool result = arena == NULL;
+
+  return wapp_tester_result(result);
+}

tests/arena/test_arena.h

@@ -0,0 +1,21 @@
+#ifndef TEST_ARENA_H
+#define TEST_ARENA_H
+
+#include "tester.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+TestFuncResult test_arena_init(void);
+TestFuncResult test_arena_init_succeeds_when_reserving_very_large_size(void);
+TestFuncResult test_arena_alloc_succeeds_when_within_capacity(void);
+TestFuncResult test_arena_alloc_fails_when_over_capacity(void);
+TestFuncResult test_arena_clear(void);
+TestFuncResult test_arena_destroy(void);
+
+#ifdef __cplusplus
+}
+#endif // __cplusplus
+
+#endif // !TEST_ARENA_H

tests/wapptest.c

@@ -0,0 +1,13 @@
+#include "test_arena.h"
+#include "tester.h"
+#include <stdlib.h>
+
+int main(void) {
+  wapp_tester_run_tests(test_arena_init,
+                        test_arena_init_succeeds_when_reserving_very_large_size,
+                        test_arena_alloc_succeeds_when_within_capacity,
+                        test_arena_alloc_fails_when_over_capacity,
+                        test_arena_clear, test_arena_destroy);
+
+  return EXIT_SUCCESS;
+}