Pepper: Log in UMA when an interface is used.

ppapi/proxy/interface_list.cc

Index: ppapi/proxy/interface_list.cc
diff --git a/ppapi/proxy/interface_list.cc b/ppapi/proxy/interface_list.cc
index 79789d70ace37d9fc95b62b3a6bb4790289e589b..ddf92b708ada3b805eb281f74fb8a7d5f070c556 100644
--- a/ppapi/proxy/interface_list.cc
+++ b/ppapi/proxy/interface_list.cc
@@ -4,6 +4,7 @@
 
 #include "ppapi/proxy/interface_list.h"
 
+#include "base/hash.h"
 #include "base/lazy_instance.h"
 #include "base/memory/singleton.h"
 #include "ppapi/c/dev/ppb_alarms_dev.h"
@@ -104,6 +105,8 @@
 #include "ppapi/c/trusted/ppb_file_chooser_trusted.h"
 #include "ppapi/c/trusted/ppb_url_loader_trusted.h"
 #include "ppapi/proxy/interface_proxy.h"
+#include "ppapi/proxy/plugin_globals.h"
+#include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/ppb_audio_proxy.h"
 #include "ppapi/proxy/ppb_broker_proxy.h"
 #include "ppapi/proxy/ppb_buffer_proxy.h"
@@ -315,15 +318,23 @@ InterfaceProxy::Factory InterfaceList::GetFactoryForID(ApiID id) const {
   return id_to_factory_[index];
 }
 
-const void* InterfaceList::GetInterfaceForPPB(const std::string& name) const {
-  NameToInterfaceInfoMap::const_iterator found =
+const void* InterfaceList::GetInterfaceForPPB(const std::string& name) {
+  NameToInterfaceInfoMap::iterator found =
       name_to_browser_info_.find(name);
   if (found == name_to_browser_info_.end())
     return NULL;
 
   if (g_process_global_permissions.Get().HasPermission(
-          found->second.required_permission))
+          found->second.required_permission)) {
+    // Only log interface use once per plugin.
+    if (!found->second.interface_logged) {
+      int hash = bit_cast<int>(base::Hash(name.c_str(), name.size()));

[Alexei Svitkine (slow), 2014/01/31 17:49:04]

What is |name| in this case? Is there a list of valid possibilities somewhere?

[teravest, 2014/02/03 15:36:55]

There's a list of valid possibilities, but it's spread across a few files.

It would include the first argument to all the calls to AddPPB in this file,
plus the first argument to the PROXIED_IFACE macro used in the header files
listed in lines 183-205.

[Alexei Svitkine (slow), 2014/02/03 19:25:10]

I think you should make an effort to enumerate these and include them as an enum
in histograms.xml. And also document the APIs that these can be passed to,
mentioning that if a new one is added, histograms.xml should be updated.

That way, the data on the dashboard can be meaningful, rather than a bunch of
undecipherable hashes.

+      PluginGlobals::Get()->GetBrowserSender()->Send(
+          new PpapiHostMsg_LogInterfaceUsage(hash));
+      found->second.interface_logged = true;
+    }
     return found->second.iface;
+  }
   return NULL;
 }