Moved sending the PluginProcessMsg_AskForShutdown message to the CreateChannel method. This ensures that it gets sent before all other messages.

Also moved the font precaching code to a common place because it is needed in multiple places.
BUG=None
TEST=Test for regressions with launching the utility process.

Review URL: http://codereview.chromium.org/2906007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@52283 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 55 insertions, 8 deletions

diff --git a/chrome/common/child_process_host.cc b/chrome/common/child_process_host.cc
index 04316502..bcd0c3d 100644
--- a/chrome/common/child_process_host.cc
+++ b/chrome/common/child_process_host.cc
@@ -5,6 +5,7 @@
 #include "chrome/common/child_process_host.h"
 
 #include "base/command_line.h"
+#include "base/histogram.h"
 #include "base/path_service.h"
 #include "chrome/common/child_process_info.h"
 #include "chrome/common/chrome_constants.h"
@@ -53,6 +54,52 @@ FilePath ChildProcessHost::GetChildPath(bool allow_self) {
   return child_path;
 }
 
+#if defined(OS_WIN)
+// static
+void ChildProcessHost::PreCacheFont(LOGFONT font) {
+  // If a child process is running in a sandbox, GetTextMetrics()
+  // can sometimes fail. If a font has not been loaded
+  // previously, GetTextMetrics() will try to load the font
+  // from the font file. However, the sandboxed process does
+  // not have permissions to access any font files and
+  // the call fails. So we make the browser pre-load the
+  // font for us by using a dummy call to GetTextMetrics of
+  // the same font.
+
+  // Maintain a circular queue for the fonts and DCs to be cached.
+  // font_index maintains next available location in the queue.
+  static const int kFontCacheSize = 32;
+  static HFONT fonts[kFontCacheSize] = {0};
+  static HDC hdcs[kFontCacheSize] = {0};
+  static size_t font_index = 0;
+
+  UMA_HISTOGRAM_COUNTS_100("Memory.CachedFontAndDC",
+      fonts[kFontCacheSize-1] ? kFontCacheSize : static_cast<int>(font_index));
+
+  HDC hdc = GetDC(NULL);
+  HFONT font_handle = CreateFontIndirect(&font);
+  DCHECK(NULL != font_handle);
+
+  HGDIOBJ old_font = SelectObject(hdc, font_handle);
+  DCHECK(NULL != old_font);
+
+  TEXTMETRIC tm;
+  BOOL ret = GetTextMetrics(hdc, &tm);
+  DCHECK(ret);
+
+  if (fonts[font_index] || hdcs[font_index]) {
+    // We already have too many fonts, we will delete one and take it's place.
+    DeleteObject(fonts[font_index]);
+    ReleaseDC(NULL, hdcs[font_index]);
+  }
+
+  fonts[font_index] = font_handle;
+  hdcs[font_index] = hdc;
+  font_index = (font_index + 1) % kFontCacheSize;
+}
+#endif  // OS_WIN
+
+
 bool ChildProcessHost::CreateChannel() {
   channel_id_ = ChildProcessInfo::GenerateRandomChannelID(this);
   channel_.reset(new IPC::Channel(
@@ -60,6 +107,14 @@ bool ChildProcessHost::CreateChannel() {
   if (!channel_->Connect())
     return false;
 
+  // Make sure these messages get sent first.
+#if defined(IPC_MESSAGE_LOG_ENABLED)
+  bool enabled = IPC::Logging::current()->Enabled();
+  SendOnChannel(new PluginProcessMsg_SetIPCLoggingEnabled(enabled));
+#endif
+
+  SendOnChannel(new PluginProcessMsg_AskBeforeShutdown());
+
   opening_channel_ = true;
 
   return true;
@@ -118,14 +173,6 @@ void ChildProcessHost::ListenerHook::OnMessageReceived(
 void ChildProcessHost::ListenerHook::OnChannelConnected(int32 peer_pid) {
   host_->opening_channel_ = false;
   host_->OnChannelConnected(peer_pid);
-
-#if defined(IPC_MESSAGE_LOG_ENABLED)
-  bool enabled = IPC::Logging::current()->Enabled();
-  host_->SendOnChannel(new PluginProcessMsg_SetIPCLoggingEnabled(enabled));
-#endif
-
-  host_->SendOnChannel(new PluginProcessMsg_AskBeforeShutdown());
-
   // Notify in the main loop of the connection.
   host_->Notify(NotificationType::CHILD_PROCESS_HOST_CONNECTED);
 }