Pepper and IPC plumbing to display message to NaCl user

The goal is to display an infobar for the user when when the NaCl
manifest does not have an entry for nexe usable on the user's
architecture (e.g. if the user is on arm but only x86 nexes have
been built).

This CL is the plumbing from the NaCl plugin (which actually
checks the manifest) into the browser process UI thread, which
can actually do the UI.

R=
sehr@chromium.org/jvoung@chromium.org (plugin, nacl_host)
brettw@chromium.org (ppapi/, chrome/renderer/pepper, chrome/browser/renderer_host)
jschuh@chromium.org (chrome/common)
BUG=154121

Review URL: https://chromiumcodereview.appspot.com/11446081

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@173139 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 35 insertions, 1 deletions

diff --git a/ppapi/api/private/ppb_nacl_private.idl b/ppapi/api/private/ppb_nacl_private.idl
index 60821c0..aa65b97 100644
--- a/ppapi/api/private/ppb_nacl_private.idl
+++ b/ppapi/api/private/ppb_nacl_private.idl
@@ -26,6 +26,15 @@ enum PP_NaClResult {
   PP_NACL_USE_SRPC = 128
 };
 
+/** NaCl-specific errors that should be reported to the user */
+enum PP_NaClError {
+  /**
+   *  The manifest program element does not contain a program usable on the
+   *  user's architecture
+  */
+  PP_NACL_MANIFEST_MISSING_ARCH = 0
+};
+
 /* PPB_NaCl_Private */
 interface PPB_NaCl_Private {
   /* Launches NaCl's sel_ldr process.  Returns PP_NACL_OK on success and writes
@@ -99,4 +108,8 @@ interface PPB_NaCl_Private {
   /* Return true if PNaCl is turned on.
    */
   PP_Bool IsPnaclEnabled();
+
+  /* Display a UI message to the user. */
+  PP_NaClResult ReportNaClError([in] PP_Instance instance,
+                                [in] PP_NaClError message_id);
 };
diff --git a/ppapi/c/private/ppb_nacl_private.h b/ppapi/c/private/ppb_nacl_private.h
index 5a4e2bf..42a6a71 100644
--- a/ppapi/c/private/ppb_nacl_private.h
+++ b/ppapi/c/private/ppb_nacl_private.h
@@ -3,7 +3,7 @@
  * found in the LICENSE file.
  */
 
-/* From private/ppb_nacl_private.idl modified Thu Nov 29 15:01:09 2012. */
+/* From private/ppb_nacl_private.idl modified Thu Dec 13 13:40:29 2012. */
 
 #ifndef PPAPI_C_PRIVATE_PPB_NACL_PRIVATE_H_
 #define PPAPI_C_PRIVATE_PPB_NACL_PRIVATE_H_
@@ -43,6 +43,15 @@ typedef enum {
   PP_NACL_USE_SRPC = 128
 } PP_NaClResult;
 PP_COMPILE_ASSERT_SIZE_IN_BYTES(PP_NaClResult, 4);
+
+/** NaCl-specific errors that should be reported to the user */
+typedef enum {
+  /**
+   *  The manifest program element does not contain a program usable on the
+   *  user's architecture
+   */
+  PP_NACL_MANIFEST_MISSING_ARCH = 0
+} PP_NaClError;
 /**
  * @}
  */
@@ -115,6 +124,9 @@ struct PPB_NaCl_Private_1_0 {
   /* Return true if PNaCl is turned on.
    */
   PP_Bool (*IsPnaclEnabled)(void);
+  /* Display a UI message to the user. */
+  PP_NaClResult (*ReportNaClError)(PP_Instance instance,
+                                   PP_NaClError message_id);
 };
 
 typedef struct PPB_NaCl_Private_1_0 PPB_NaCl_Private;
diff --git a/ppapi/native_client/src/trusted/plugin/plugin.cc b/ppapi/native_client/src/trusted/plugin/plugin.cc
index 866762a..c8c9194 100644
--- a/ppapi/native_client/src/trusted/plugin/plugin.cc
+++ b/ppapi/native_client/src/trusted/plugin/plugin.cc
@@ -1678,6 +1678,15 @@ void Plugin::ReportLoadSuccess(LengthComputable length_computable,
 void Plugin::ReportLoadError(const ErrorInfo& error_info) {
   PLUGIN_PRINTF(("Plugin::ReportLoadError (error='%s')\n",
                  error_info.message().c_str()));
+  // For errors the user (and not just the developer) should know about,
+  // report them to the renderer so the browser can display a message.
+  if (error_info.error_code() == ERROR_MANIFEST_PROGRAM_MISSING_ARCH) {
+    // A special case: the manifest may otherwise be valid but is missing
+    // a program/file compatible with the user's sandbox.
+    nacl_interface()->ReportNaClError(pp_instance(),
+                                      PP_NACL_MANIFEST_MISSING_ARCH);
+  }
+
   // Set the readyState attribute to indicate we need to start over.
   set_nacl_ready_state(DONE);
   set_nexe_error_reported(true);