Add a MemoryBuffer type to safely allocate large user data buffers.

MemoryBuffer has a similar interface to std::vector but returns a bool on
resize to do error checking.

BUG=angle:700

Change-Id: Ib201eeb91b07f5b7f970e153f5d1e110f9b2fa55
Reviewed-on: https://chromium-review.googlesource.com/209612
Reviewed-by: Nico Weber <thakis@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>

7 files changed, 133 insertions, 10 deletions

diff --git a/src/libGLESv2.gypi b/src/libGLESv2.gypi
index 2256e7b3..f58967be 100644
--- a/src/libGLESv2.gypi
+++ b/src/libGLESv2.gypi
@@ -147,6 +147,8 @@
             'libGLESv2/renderer/d3d/IndexBuffer.h',
             'libGLESv2/renderer/d3d/IndexDataManager.cpp',
             'libGLESv2/renderer/d3d/IndexDataManager.h',
+            'libGLESv2/renderer/d3d/MemoryBuffer.cpp',
+            'libGLESv2/renderer/d3d/MemoryBuffer.h',
             'libGLESv2/renderer/d3d/TextureD3D.cpp',
             'libGLESv2/renderer/d3d/TextureD3D.h',
             'libGLESv2/renderer/d3d/TextureStorage.cpp',
diff --git a/src/libGLESv2/renderer/d3d/MemoryBuffer.cpp b/src/libGLESv2/renderer/d3d/MemoryBuffer.cpp
new file mode 100644
index 00000000..301bbe8d
--- /dev/null
+++ b/src/libGLESv2/renderer/d3d/MemoryBuffer.cpp
@@ -0,0 +1,72 @@
+//
+// Copyright (c) 2014 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+#include "libGLESv2/renderer/d3d/MemoryBuffer.h"
+
+#include <algorithm>
+#include <cstdlib>
+
+namespace rx
+{
+
+MemoryBuffer::MemoryBuffer()
+    : mSize(0),
+      mData(NULL)
+{
+}
+
+MemoryBuffer::~MemoryBuffer()
+{
+    free(mData);
+    mData = NULL;
+}
+
+bool MemoryBuffer::resize(size_t size)
+{
+    if (size == 0)
+    {
+        free(mData);
+        mData = NULL;
+        mSize = 0;
+    }
+    else
+    {
+        uint8_t *newMemory = reinterpret_cast<uint8_t*>(malloc(sizeof(uint8_t) * size));
+        if (newMemory == NULL)
+        {
+            return false;
+        }
+
+        if (mData)
+        {
+            // Copy the intersection of the old data and the new data
+            std::copy(mData, mData + std::min(mSize, size), newMemory);
+            free(mData);
+        }
+
+        mData = newMemory;
+        mSize = size;
+    }
+
+    return true;
+}
+
+size_t MemoryBuffer::size() const
+{
+    return mSize;
+}
+
+const uint8_t *MemoryBuffer::data() const
+{
+    return mData;
+}
+
+uint8_t *MemoryBuffer::data()
+{
+    return mData;
+}
+
+}
diff --git a/src/libGLESv2/renderer/d3d/MemoryBuffer.h b/src/libGLESv2/renderer/d3d/MemoryBuffer.h
new file mode 100644
index 00000000..2484c074
--- /dev/null
+++ b/src/libGLESv2/renderer/d3d/MemoryBuffer.h
@@ -0,0 +1,35 @@
+//
+// Copyright (c) 2014 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+#ifndef LIBGLESV2_RENDERER_D3D_MEMORYBUFFER_H_
+#define LIBGLESV2_RENDERER_D3D_MEMORYBUFFER_H_
+
+#include <cstddef>
+#include <cstdint>
+
+namespace rx
+{
+
+class MemoryBuffer
+{
+  public:
+    MemoryBuffer();
+    ~MemoryBuffer();
+
+    bool resize(size_t size);
+    size_t size() const;
+
+    const uint8_t *data() const;
+    uint8_t *data();
+
+  private:
+    size_t mSize;
+    uint8_t *mData;
+};
+
+}
+
+#endif // LIBGLESV2_RENDERER_D3D_MEMORYBUFFER_H
diff --git a/src/libGLESv2/renderer/d3d/d3d11/Buffer11.cpp b/src/libGLESv2/renderer/d3d/d3d11/Buffer11.cpp
index facd7098..b677fb5f 100644
--- a/src/libGLESv2/renderer/d3d/d3d11/Buffer11.cpp
+++ b/src/libGLESv2/renderer/d3d/d3d11/Buffer11.cpp
@@ -148,7 +148,7 @@ class Buffer11::PackStorage11 : public Buffer11::BufferStorage11
     ID3D11Texture2D *mStagingTexture;
     DXGI_FORMAT mTextureFormat;
     gl::Extents mTextureSize;
-    std::vector<unsigned char> mMemoryBuffer;
+    MemoryBuffer mMemoryBuffer;
     PackPixelsParams *mQueuedPackCommand;
     PackPixelsParams mPackParams;
     bool mDataModified;
@@ -215,7 +215,10 @@ void *Buffer11::getData()
     {
         if (stagingBuffer->getSize() > mResolvedData.size())
         {
-            mResolvedData.resize(stagingBuffer->getSize());
+            if (!mResolvedData.resize(stagingBuffer->getSize()))
+            {
+                return gl::error(GL_OUT_OF_MEMORY, (void*)NULL);
+            }
         }
 
         ID3D11DeviceContext *context = mRenderer->getDeviceContext();
@@ -789,7 +792,10 @@ bool Buffer11::PackStorage11::resize(size_t size, bool preserveData)
 {
     if (size != mBufferSize)
     {
-        mMemoryBuffer.resize(size, 0);
+        if (!mMemoryBuffer.resize(size))
+        {
+            return false;
+        }
         mBufferSize = size;
     }
 
@@ -807,7 +813,7 @@ void *Buffer11::PackStorage11::map(size_t offset, size_t length, GLbitfield acce
     flushQueuedPackCommand();
     mDataModified = (mDataModified || (access & GL_MAP_WRITE_BIT) != 0);
 
-    return &mMemoryBuffer[0] + offset;
+    return mMemoryBuffer.data() + offset;
 }
 
 void Buffer11::PackStorage11::unmap()
@@ -880,11 +886,11 @@ void Buffer11::PackStorage11::packPixels(ID3D11Texture2D *srcTexure, UINT srcSub
 
 void Buffer11::PackStorage11::flushQueuedPackCommand()
 {
-    ASSERT(!mMemoryBuffer.empty());
+    ASSERT(mMemoryBuffer.size() > 0);
 
     if (mQueuedPackCommand)
     {
-        mRenderer->packPixels(mStagingTexture, *mQueuedPackCommand, &mMemoryBuffer[0]);
+        mRenderer->packPixels(mStagingTexture, *mQueuedPackCommand, mMemoryBuffer.data());
         SafeDelete(mQueuedPackCommand);
     }
 }
diff --git a/src/libGLESv2/renderer/d3d/d3d11/Buffer11.h b/src/libGLESv2/renderer/d3d/d3d11/Buffer11.h
index 43f95c34..e56be247 100644
--- a/src/libGLESv2/renderer/d3d/d3d11/Buffer11.h
+++ b/src/libGLESv2/renderer/d3d/d3d11/Buffer11.h
@@ -10,6 +10,7 @@
 #define LIBGLESV2_RENDERER_BUFFER11_H_
 
 #include "libGLESv2/renderer/d3d/BufferD3D.h"
+#include "libGLESv2/renderer/d3d/MemoryBuffer.h"
 #include "libGLESv2/angletypes.h"
 
 namespace rx
@@ -88,7 +89,7 @@ class Buffer11 : public BufferD3D
     typedef std::pair<ID3D11Buffer *, ID3D11ShaderResourceView *> BufferSRVPair;
     std::map<DXGI_FORMAT, BufferSRVPair> mBufferResourceViews;
 
-    std::vector<unsigned char> mResolvedData;
+    MemoryBuffer mResolvedData;
     DataRevision mResolvedDataRevision;
     unsigned int mReadUsageCount;
 
diff --git a/src/libGLESv2/renderer/d3d/d3d9/Buffer9.cpp b/src/libGLESv2/renderer/d3d/d3d9/Buffer9.cpp
index c86fe136..347bde0c 100644
--- a/src/libGLESv2/renderer/d3d/d3d9/Buffer9.cpp
+++ b/src/libGLESv2/renderer/d3d/d3d9/Buffer9.cpp
@@ -42,7 +42,10 @@ void Buffer9::setData(const void* data, size_t size, GLenum usage)
 {
     if (size > mMemory.size())
     {
-        mMemory.resize(size);
+        if (!mMemory.resize(size))
+        {
+            return gl::error(GL_OUT_OF_MEMORY);
+        }
     }
 
     mSize = size;
@@ -70,7 +73,10 @@ void Buffer9::setSubData(const void* data, size_t size, size_t offset)
 {
     if (offset + size > mMemory.size())
     {
-        mMemory.resize(offset + size);
+        if (!mMemory.resize(offset + size))
+        {
+            return gl::error(GL_OUT_OF_MEMORY);
+        }
     }
 
     mSize = std::max(mSize, offset + size);
diff --git a/src/libGLESv2/renderer/d3d/d3d9/Buffer9.h b/src/libGLESv2/renderer/d3d/d3d9/Buffer9.h
index 0f80d074..ec25ec30 100644
--- a/src/libGLESv2/renderer/d3d/d3d9/Buffer9.h
+++ b/src/libGLESv2/renderer/d3d/d3d9/Buffer9.h
@@ -10,6 +10,7 @@
 #define LIBGLESV2_RENDERER_BUFFER9_H_
 
 #include "libGLESv2/renderer/d3d/BufferD3D.h"
+#include "libGLESv2/renderer/d3d/MemoryBuffer.h"
 #include "libGLESv2/angletypes.h"
 
 namespace rx
@@ -43,7 +44,7 @@ class Buffer9 : public BufferD3D
     DISALLOW_COPY_AND_ASSIGN(Buffer9);
 
     rx::Renderer9 *mRenderer;
-    std::vector<char> mMemory;
+    MemoryBuffer mMemory;
     size_t mSize;
 };