Linux: don't try and read shmmax in the sandbox.

chrome/renderer/render_process.cc

 // Copyright (c) 2006-2008 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 "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <objidl.h>
 #include <mlang.h>
@@ skipping 14 matching lines @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/transport_dib.h"
 #include "chrome/renderer/render_view.h"
 #include "ipc/ipc_channel.h"
 #include "ipc/ipc_message_utils.h"
 #include "media/base/media.h"
 #include "webkit/glue/webkit_glue.h"
 
-static size_t GetMaxSharedMemorySize() {
-  static int size = 0;
-#if defined(OS_LINUX)
-  if (size == 0) {
-    std::string contents;
-    file_util::ReadFileToString(FilePath("/proc/sys/kernel/shmmax"), &contents);
-    size = strtoul(contents.c_str(), NULL, 0);
-  }
-#endif
-  return size;
-}
-
 //-----------------------------------------------------------------------------
 
 RenderProcess::RenderProcess()
     : ALLOW_THIS_IN_INITIALIZER_LIST(shared_mem_cache_cleaner_(
           base::TimeDelta::FromSeconds(5),
           this, &RenderProcess::ClearTransportDIBCache)),
       sequence_number_(0) {
   in_process_plugins_ = InProcessPlugins();
   for (size_t i = 0; i < arraysize(shared_mem_cache_); ++i)
     shared_mem_cache_[i] = NULL;
@@ skipping 102 matching lines @@
 }
 
 // -----------------------------------------------------------------------------
 
 
 skia::PlatformCanvas* RenderProcess::GetDrawingCanvas(
     TransportDIB** memory, const gfx::Rect& rect) {
   int width = rect.width();
   int height = rect.height();
   const size_t stride = skia::PlatformCanvas::StrideForWidth(rect.width());
-  const size_t max_size = GetMaxSharedMemorySize();
+  const size_t max_size = base::SysInfo::MaxSharedMemorySize();
 
   // If the requested size is too big, reduce the height. Ideally we might like
   // to reduce the width as well to make the size reduction more "balanced", but
   // it rarely comes up in practice.
   if ((max_size != 0) && (height * stride > max_size))
     height = max_size / stride;
 
   const size_t size = height * stride;
 
   if (!GetTransportDIBFromCache(memory, size)) {
@@ skipping 67 matching lines @@
 }
 
 void RenderProcess::ClearTransportDIBCache() {
   for (size_t i = 0; i < arraysize(shared_mem_cache_); ++i) {
     if (shared_mem_cache_[i]) {
       FreeTransportDIB(shared_mem_cache_[i]);
       shared_mem_cache_[i] = NULL;
     }
   }
 }