Initial Mangos Three Commit

dep/g3dlite/G3D/AreaMemoryManager.cpp

@@ -0,0 +1,87 @@
+/**
+ @file AreaMemoryManager.cpp
+  
+ @maintainer Morgan McGuire, http://graphics.cs.williams.edu
+
+ @created 2009-01-20
+ @edited  2009-01-20
+
+ Copyright 2000-2009, Morgan McGuire.
+ All rights reserved.
+ */
+
+#include "G3D/AreaMemoryManager.h"
+#include "G3D/System.h"
+
+namespace G3D {
+
+AreaMemoryManager::Buffer::Buffer(size_t size) : m_size(size), m_used(0) {
+    // Allocate space for a lot of buffers.
+    m_first = (uint8*)::malloc(m_size);
+}
+
+
+AreaMemoryManager::Buffer::~Buffer() {
+    ::free(m_first);
+}
+
+
+void* AreaMemoryManager::Buffer::alloc(size_t s) {
+    if (s + m_used > m_size) {
+        return NULL;
+    } else {
+        void* old = m_first + m_used;
+        m_used += s;
+        return old;
+    }
+}
+
+
+bool AreaMemoryManager::isThreadsafe() const {
+    return false;
+}
+
+
+AreaMemoryManager::Ref AreaMemoryManager::create(size_t sizeHint) {
+    return new AreaMemoryManager(sizeHint);
+}
+
+
+AreaMemoryManager::AreaMemoryManager(size_t sizeHint) : m_sizeHint(sizeHint) {
+    debugAssert(sizeHint > 0);
+}
+
+
+AreaMemoryManager::~AreaMemoryManager() {
+    deallocateAll();
+}
+
+
+size_t AreaMemoryManager::bytesAllocated() const {
+    return m_sizeHint * m_bufferArray.size();
+}
+
+
+void* AreaMemoryManager::alloc(size_t s) {
+    void* n = (m_bufferArray.size() > 0) ? m_bufferArray.last()->alloc(s) : NULL;
+    if (n == NULL) {
+        // This buffer is full
+        m_bufferArray.append(new Buffer(max(s, m_sizeHint)));
+        return m_bufferArray.last()->alloc(s);
+    } else {
+        return n;
+    }
+}
+
+
+void AreaMemoryManager::free(void* x) {
+    // Intentionally empty; we block deallocate
+}
+
+
+void AreaMemoryManager::deallocateAll() {
+    m_bufferArray.deleteAll();
+    m_bufferArray.clear();
+}
+
+}