From a99f159a8eab4c20d99cbe0218c367a6fa4d904c Mon Sep 17 00:00:00 2001
From: Ivar Fatland <fatland99@hotmail.com>
Date: Sat, 4 Oct 2025 00:42:16 +0200
Subject: [PATCH] started work on buffer allocator interface

---
 allocator.h        | 20 ++++++++++++++++++++
 buffer_allocator.c | 31 +++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)
 create mode 100644 buffer_allocator.c

diff --git a/allocator.h b/allocator.h
index 81ee097..0708998 100644
--- a/allocator.h
+++ b/allocator.h
@@ -2,8 +2,11 @@
 #define ALLOCATOR_H
 
 #include <stddef.h>
+#include <stdint.h>
 #include <stdlib.h>
 
+#define MAX_ALIGN (sizeof(union { char c; int i; long l; long long ll; float f; double d; void *p; }))
+
 // Contains all operations an allocator can do. Similar interface to sdtlibs
 // malloc, realloc and free.
 typedef struct allocator_vtbl {
@@ -27,7 +30,23 @@ void allocator_free_func(allocator_t this, void *ptr, const char *file, int line
 #define allocator_resize(this, old_ptr, bytes) allocator_resize_func(this, old_ptr, bytes, __FILE__, __LINE__)
 #define allocator_free(this, ptr) allocator_free_func(this, ptr, __FILE__, __LINE__)
 
+// std_allocator ///////////////////////////////////////////////////////////////
 extern const allocator_t allocator_stdlib;
+// buffer_allocator ////////////////////////////////////////////////////////////
+typedef struct buffer_allocator {
+    size_t size, capacity;
+    uint8_t *data;
+} buffer_allocator_t;
+
+#define buffer_allocator_stack_create(CAPACITY)                                       \
+  ((buffer_allocator_t){                                                       \
+      .size = 0, .capacity = CAPACITY, .data = (uint8_t[CAPACITY]){}})
+
+buffer_allocator_t *buffer_allocator_heap_create(allocator_t alloc, size_t capacity);
+void buffer_allocator_heap_destroy(allocator_t alloc, buffer_allocator_t *this);
+// TODO: maybe use the macro magic to use the standard allcocator as the default
+// one? or make users define a STANDARD_ALLOCATOR value? need to think about the
+// consequenses
 
 #ifdef ALLOCATOR_IMPLEMENTATION
 
@@ -42,6 +61,7 @@ void allocator_free_func(allocator_t this, void *ptr, const char *file, int line
 }
 
 #include "std_allocator.c"
+#include "buffer_allocator.c"
 
 #endif // ALLOCATOR_IMPLEMENTATION
 #endif // ALLOCATOR_H
diff --git a/buffer_allocator.c b/buffer_allocator.c
new file mode 100644
index 0000000..3a79495
--- /dev/null
+++ b/buffer_allocator.c
@@ -0,0 +1,31 @@
+#include "allocator.h"
+
+// TODO
+
+static void *buffer_alloc(void *this, size_t bytes, const char *file, int line) {
+    (void)this;
+    (void)bytes;
+    (void)file;
+    (void)line;
+    return 0;
+}
+static void *buffer_resize(void *this, void *old_ptr, size_t bytes, const char *file, int line) {
+    (void)this;
+    (void)old_ptr;
+    (void)bytes;
+    (void)file;
+    (void)line;
+    return 0;
+}
+static void buffer_free(void *this, void *ptr, const char *file, int line) {
+    (void)this;
+    (void)ptr;
+    (void)file;
+    (void)line;
+}
+
+static const allocator_vtbl_t buffer_vtbl = {
+    .alloc = buffer_alloc,
+    .resize = buffer_resize,
+    .free = buffer_free,
+};