1 files changed, 51 insertions, 0 deletions
diff --git a/src/max_heap_allocator.zig b/src/max_heap_allocator.zig
new file mode 100644
index 000000000..ea616c9ca
--- /dev/null
+++ b/src/max_heap_allocator.zig
@@ -0,0 +1,51 @@
+const bun = @import("root").bun;
+const std = @import("std");
+
+/// Single allocation only.
+///
+pub const MaxHeapAllocator = struct {
+    array_list: std.ArrayList(u8),
+
+    fn alloc(ptr: *anyopaque, len: usize, _: u8, _: usize) ?[*]u8 {
+        var this = bun.cast(*MaxHeapAllocator, ptr);
+        this.array_list.items.len = 0;
+        this.array_list.ensureTotalCapacity(len) catch return null;
+        this.array_list.items.len = len;
+        return this.array_list.items.ptr;
+    }
+
+    fn resize(_: *anyopaque, buf: []u8, _: u8, new_len: usize, _: usize) bool {
+        _ = new_len;
+        _ = buf;
+        @panic("not implemented");
+    }
+
+    fn free(
+        _: *anyopaque,
+        _: []u8,
+        _: u8,
+        _: usize,
+    ) void {}
+
+    pub fn reset(this: *MaxHeapAllocator) void {
+        this.array_list.items.len = 0;
+    }
+
+    pub fn deinit(this: *MaxHeapAllocator) void {
+        this.array_list.deinit();
+    }
+
+    const vtable = std.mem.Allocator.VTable{
+        .alloc = &alloc,
+        .free = &free,
+        .resize = &resize,
+    };
+    pub fn init(this: *MaxHeapAllocator, allocator: std.mem.Allocator) std.mem.Allocator {
+        this.array_list = std.ArrayList(u8).init(allocator);
+
+        return std.mem.Allocator{
+            .ptr = this,
+            .vtable = &vtable,
+        };
+    }
+};