Tweaks to PPB_VarArrayBuffer in preperation for taking out of Dev.

ppapi/cpp/dev/var_array_buffer_dev.cc

 // Copyright (c) 2011 The Chromium 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 "ppapi/cpp/dev/var_array_buffer_dev.h"
 
+#include <limits>
+
 #include "ppapi/c/dev/ppb_var_array_buffer_dev.h"
 #include "ppapi/cpp/logging.h"
 #include "ppapi/cpp/module_impl.h"
 
 namespace pp {
 
 namespace {
 
 template <> const char* interface_name<PPB_VarArrayBuffer_Dev>() {
   return PPB_VAR_ARRAY_BUFFER_DEV_INTERFACE;
 }
 
 }  // namespace
 
-VarArrayBuffer_Dev::VarArrayBuffer_Dev(const Var& var)
-    : Var(var), buffer_(NULL) {
-  if (var.is_array_buffer()) {
-    buffer_ = Map();
-  } else {
+VarArrayBuffer_Dev::VarArrayBuffer_Dev(const Var& var) : Var(var) {
+  if (!var.is_array_buffer()) {
     PP_NOTREACHED();
     var_ = PP_MakeNull();
   }
 }
 
-VarArrayBuffer_Dev::VarArrayBuffer_Dev(uint32_t size_in_bytes)
-    : buffer_(NULL) {
+VarArrayBuffer_Dev::VarArrayBuffer_Dev(uint32_t size_in_bytes) {
   if (has_interface<PPB_VarArrayBuffer_Dev>()) {
     var_ = get_interface<PPB_VarArrayBuffer_Dev>()->Create(size_in_bytes);
     needs_release_ = true;
-    buffer_ = Map();
   } else {
     PP_NOTREACHED();
     var_ = PP_MakeNull();
   }
 }
 
 uint32_t VarArrayBuffer_Dev::ByteLength() const {
-  if (has_interface<PPB_VarArrayBuffer_Dev>()) {
-    return get_interface<PPB_VarArrayBuffer_Dev>()->ByteLength(var_);
-  }
-  PP_NOTREACHED();
-  return 0;
-}
-
-const void* VarArrayBuffer_Dev::Map() const {
-  return const_cast<VarArrayBuffer_Dev*>(this)->Map();
+  uint32_t byte_length = std::numeric_limits<uint32_t>::max();
+  if (is_array_buffer() && has_interface<PPB_VarArrayBuffer_Dev>())
+    get_interface<PPB_VarArrayBuffer_Dev>()->ByteLength(var_, &byte_length);
+  else
+    PP_NOTREACHED();
+  return byte_length;
 }
 
 void* VarArrayBuffer_Dev::Map() {
-  // TODO(dmichael): This is not thread-safe.
-  if (buffer_)
-    return buffer_;
-  if (has_interface<PPB_VarArrayBuffer_Dev>()) {
-    buffer_ = get_interface<PPB_VarArrayBuffer_Dev>()->Map(var_);
-    return buffer_;
-  }
+  if (is_array_buffer() && has_interface<PPB_VarArrayBuffer_Dev>())
+    return get_interface<PPB_VarArrayBuffer_Dev>()->Map(var_);
   PP_NOTREACHED();
-  return 0;
+  return NULL;
+}
+
+void VarArrayBuffer_Dev::Unmap() {
+  if (is_array_buffer() && has_interface<PPB_VarArrayBuffer_Dev>())
+    get_interface<PPB_VarArrayBuffer_Dev>()->Map(var_);

[bbudge, 2012/01/25 22:19:07]

Shouldn't this call UnMap?

[dmichael (off chromium), 2012/01/25 23:50:11]

Unmap is only an optimization for apps that want to save memory but still have
access to the buffer later.

+  else
+    PP_NOTREACHED();
 }
 
 }  // namespace pp