complete ble ota move

src/esp32/SimpleAllocator.h

@@ -0,0 +1,42 @@
+#pragma once
+#include <Arduino.h>
+
+#define POOL_SIZE 16384
+
+/**
+ * An allocator (and placement new operator) that allocates storage from a fixed sized buffer.
+ * It will panic if that buffer fills up.
+ * If you are _sure_ no outstanding references to blocks in this buffer still exist, you can call
+ * reset() to start from scratch.
+ * 
+ * Currently the only usecase for this class is the ESP32 bluetooth stack, where once we've called deinit(false)
+ * we are sure all those bluetooth objects no longer exist, and we'll need to recreate them when we restart bluetooth
+ */
+class SimpleAllocator
+{
+    uint8_t bytes[POOL_SIZE];
+
+    uint32_t nextFree;
+
+public:
+    SimpleAllocator();
+
+    void *alloc(size_t size);
+
+    /** If you are _sure_ no outstanding references to blocks in this buffer still exist, you can call
+ * reset() to start from scratch.
+ * */
+    void reset();
+};
+
+void *operator new(size_t size, SimpleAllocator &p);
+
+/**
+ * Temporarily makes the specified Allocator be used for _all_ allocations.  Useful when calling library routines
+ * that don't know about pools
+ */
+class AllocatorScope {
+public:
+    AllocatorScope(SimpleAllocator &a);
+    ~AllocatorScope();
+};