[Mammoth] Write a custom buddy allocator to replace libc malloc.

lib/libc/CMakeLists.txt

@@ -1,6 +1,5 @@
 
 add_library(c STATIC
-  src/malloc.cpp
   src/string.cpp
   )
 

lib/libc/include/stdlib.h

@@ -1,5 +0,0 @@
-#pragma once
-
-#include "stddef.h"
-
-void* malloc(size_t size);

lib/libc/src/malloc.cpp

@@ -1,46 +0,0 @@
-#include <zcall.h>
-#include <zglobal.h>
-
-#include "stdlib.h"
-
-namespace {
-class NaiveAllocator {
- public:
-  constexpr static uint64_t kSize = 0x10000;
-  NaiveAllocator() {}
-  bool is_init() { return next_addr_ != 0; }
-  void Init() {
-    uint64_t vmmo_cap;
-    uint64_t err = ZMemoryObjectCreate(kSize, &vmmo_cap);
-    if (err != 0) {
-      (void)ZProcessExit(err);
-    }
-    err = ZAddressSpaceMap(gSelfVmasCap, 0, vmmo_cap, 0, &next_addr_);
-    max_addr_ = next_addr_ + kSize;
-  }
-
-  void* Allocate(size_t size) {
-    uint64_t addr = next_addr_;
-    next_addr_ += size;
-    if (next_addr_ >= max_addr_) {
-      (void)ZProcessExit(0xBEEF);
-      return 0;
-    }
-    return reinterpret_cast<void*>(addr);
-  }
-
- private:
-  uint64_t next_addr_ = 0;
-  uint64_t max_addr_ = 0;
-};
-
-NaiveAllocator gAlloc;
-
-}  // namespace
-
-void* malloc(size_t size) {
-  if (!gAlloc.is_init()) {
-    gAlloc.Init();
-  }
-  return gAlloc.Allocate(size);
-}