1 files changed, 118 insertions, 0 deletions
diff --git a/rend_vk_allocator.c b/rend_vk_allocator.c
new file mode 100644
index 0000000..737e566
--- /dev/null
+++ b/rend_vk_allocator.c
@@ -0,0 +1,118 @@
+#pragma once
+#include "rend_internal.h"
+#include <stdint.h>
+#include <vulkan/vulkan.h>
+#include <vulkan/vulkan_core.h>
+
+typedef struct RendVkAllocatorState {
+    const char *name;
+} RendVkAllocatorState;
+
+typedef struct RendVkAllocatorHeader {
+    uint32_t offset; 
+} RendVkAllocatorHeader;
+
+static bool rend_vk_allocator_is_power_of_two(uintptr_t x);
+static void *rend_vk_allocator_alloc(void *pUserData, size_t size, size_t alignment, VkSystemAllocationScope allocationScope);
+static void *rend_vk_allocator_realloc(void *pUserData, void *pOriginal, size_t size, size_t alignment, VkSystemAllocationScope allocationScope);
+static void rend_vk_allocator_free(void *pUserData, void *pMemory);
+static void rend_vk_allocator_internal_notification(void *pUserData, size_t size, VkInternalAllocationType allocationType, VkSystemAllocationScope allocationScope);
+static void rend_vk_allocator_free_notification(void *pUserData, size_t size, VkInternalAllocationType allocationType, VkSystemAllocationScope allocationScope);
+
+static VkAllocationCallbacks rend_vk_allocator = {
+    .pfnAllocation = rend_vk_allocator_alloc,
+    .pfnReallocation = rend_vk_allocator_realloc,
+    .pfnFree = rend_vk_allocator_free,
+    .pfnInternalAllocation = rend_vk_allocator_internal_notification,
+    .pfnInternalFree = rend_vk_allocator_free_notification,
+};
+
+static const char* rend_vk_allocator_scope_name[] = {
+    [VK_SYSTEM_ALLOCATION_SCOPE_CACHE] = "Cache",
+    [VK_SYSTEM_ALLOCATION_SCOPE_COMMAND] = "Command",
+    [VK_SYSTEM_ALLOCATION_SCOPE_DEVICE] = "Device",
+    [VK_SYSTEM_ALLOCATION_SCOPE_INSTANCE] = "Instance",
+    [VK_SYSTEM_ALLOCATION_SCOPE_OBJECT] = "Object",
+};
+
+
+static bool
+rend_vk_allocator_is_power_of_two(uintptr_t x) 
+{
+	return (x & (x-1)) == 0;
+}
+
+static uintptr_t
+rend_vk_allocator_align_forward(uintptr_t ptr, size_t align) 
+{
+	uintptr_t p, a, modulo;
+
+	assert(rend_vk_allocator_is_power_of_two(align));
+
+	p = ptr;
+	a = (uintptr_t)align;
+	modulo = p & (a-1);
+
+	if (modulo != 0) {
+		p += a - modulo;
+	}
+	return p;
+}
+
+static void* 
+rend_vk_allocator_alloc(void *pUserData, size_t size, size_t alignment, VkSystemAllocationScope allocationScope)
+{
+    size_t total_size = size + alignment + sizeof (RendVkAllocatorHeader);
+    uint8_t *raw_ptr = malloc(total_size);
+    uintptr_t unaligned_addr = (uintptr_t)(raw_ptr + sizeof (RendVkAllocatorHeader));
+
+    uint8_t *aligned_ptr = (uint8_t*)rend_vk_allocator_align_forward(unaligned_addr, alignment);
+    RendVkAllocatorHeader *header = (RendVkAllocatorHeader*) aligned_ptr - 1;
+    header->offset = aligned_ptr - raw_ptr;
+
+    PDEBUG("[VK_ALLOC] %p - bytes %lu with alignment %lu - scope %s",
+            aligned_ptr, size, alignment, rend_vk_allocator_scope_name[allocationScope]);
+
+    return (void*) aligned_ptr;
+}
+
+static void*
+rend_vk_allocator_realloc(void *pUserData, void *pOriginal, size_t size, size_t alignment, VkSystemAllocationScope allocationScope)
+{
+    if (!pOriginal) return rend_vk_allocator_alloc(pUserData, size, alignment, allocationScope);
+    if (size == 0) {
+        rend_vk_allocator_free(pUserData, pOriginal);
+        return NULL;
+    }
+    void *new_ptr = rend_vk_allocator_alloc(pUserData, size, alignment, allocationScope);
+    if (!new_ptr) return NULL;
+    memcpy(new_ptr, pOriginal, size);
+    rend_vk_allocator_free(pUserData, pOriginal);
+    return new_ptr;
+}
+
+static void
+rend_vk_allocator_free(void *pUserData, void *pMemory)
+{
+    RendVkAllocatorHeader *ptr = pMemory;
+    uint8_t *raw_ptr = pMemory;
+    raw_ptr -= (ptr-1)->offset;
+
+    PDEBUG("[VK_FREE] %p", ptr);
+    free(raw_ptr);
+}
+
+static void
+rend_vk_allocator_internal_notification(void *pUserData, size_t size, VkInternalAllocationType allocationType, VkSystemAllocationScope allocationScope)
+{
+    PDEBUG("[VK_ALLOC_INTERNAL] bytes %lu - scope %s",
+            size, rend_vk_allocator_scope_name[allocationScope]);
+
+}
+
+static void
+rend_vk_allocator_free_notification(void *pUserData, size_t size, VkInternalAllocationType allocationType, VkSystemAllocationScope allocationScope)
+{
+    PDEBUG("[VK_FREE_INTERNAL] bytes %lu - scope %s",
+            size, rend_vk_allocator_scope_name[allocationScope]);
+}