Set Android/V8 memory limits from dalvik.vm.heapsize.

webkit/glue/dalvik_heap_size_android.cc

Index: webkit/glue/dalvik_heap_size_android.cc
diff --git a/webkit/glue/dalvik_heap_size_android.cc b/webkit/glue/dalvik_heap_size_android.cc
new file mode 100644
index 0000000000000000000000000000000000000000..43c79fe31c1e545c8c91c12cdde5a70d8664b1be
--- /dev/null
+++ b/webkit/glue/dalvik_heap_size_android.cc
@@ -0,0 +1,58 @@
+// Copyright (c) 2012 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 "webkit/glue/dalvik_heap_size_android.h"
+
+#include <sys/system_properties.h>
+
+#include "base/memory/singleton.h"
+#include "base/string_number_conversions.h"
+
+namespace webkit_glue {
+DalvikHeapSize* DalvikHeapSize::GetInstance() {
+  return Singleton<DalvikHeapSize>::get();
+}
+
+DalvikHeapSize::DalvikHeapSize() : heap_size_mb_(0) {
+  char heap_size_str[PROP_VALUE_MAX];
+  __system_property_get("dalvik.vm.heapsize", heap_size_str);
+  heap_size_mb_ = ParseHeapSize(std::string(heap_size_str));
+}
+
+DalvikHeapSize::~DalvikHeapSize() {}
+
+int DalvikHeapSize::HeapSizeMB() const {
+  return heap_size_mb_;
+}
+
+int DalvikHeapSize::ParseHeapSize(const std::string& str) const {
+  const int64 KB = 1024;
+  const int64 MB = 1024 * KB;
+  const int64 GB = 1024 * MB;
+  CHECK_GT(str.size(), 0u);
+  int64 factor = 1;
+  size_t length = str.size();
+  if (str[length - 1] == 'k') {
+    factor = KB;
+    length--;
+  } else if (str[length - 1] == 'm') {
+    factor = MB;
+    length--;
+  } else if (str[length - 1] == 'g') {
+    factor = GB;
+    length--;
+  } else {
+    CHECK('0' <= str[length - 1] && str[length - 1] <= '9');
+  }
+  int64 result = 0;
+  bool parsed = base::StringToInt64(str.substr(0, length), &result);
+  CHECK(parsed);
+  result = result * factor / MB;
+  // dalvik.vm.heapsize property is writable by user,
+  // truncate it to reasonable value to avoid overflows later.
+  result = std::min<int64>(std::max<int64>(32, result), 1024);
+  return static_cast<int>(result);
+}
+
+}  // webkit_glue namespace