From ec2330a796c963c8777b3421a662d589e872d070 Mon Sep 17 00:00:00 2001
From: Philippe Normand <philn@igalia.com>
Date: Sat, 24 Sep 2022 17:03:22 +0100
Subject: [PATCH] wpe: Add a basic WebProcess crash handler

For now an error is emitted. Additional notification could be sent to the
application as well, if needed.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3077>
---
 .../ext/wpe/WPEThreadedView.cpp               | 20 +++++++++++++++++++
 .../gst-plugins-bad/ext/wpe/WPEThreadedView.h |  6 +++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/subprojects/gst-plugins-bad/ext/wpe/WPEThreadedView.cpp b/subprojects/gst-plugins-bad/ext/wpe/WPEThreadedView.cpp
index abc505d8dd..c195ede08a 100644
--- a/subprojects/gst-plugins-bad/ext/wpe/WPEThreadedView.cpp
+++ b/subprojects/gst-plugins-bad/ext/wpe/WPEThreadedView.cpp
@@ -399,7 +399,26 @@ static void s_loadProgressChanged(GObject* object, GParamSpec*, gpointer data)
     gst_object_unref (bus);
 }
 
+static void s_webProcessCrashed(WebKitWebView*, WebKitWebProcessTerminationReason reason, gpointer data)
+{
+    auto &view = *static_cast<WPEView *>(data);
+    auto *src = view.src();
+    gchar *reason_str =
+        g_enum_to_string (WEBKIT_TYPE_WEB_PROCESS_TERMINATION_REASON, reason);
+
+    // In case the crash happened while doing the initial URL loading, unlock
+    // the load completion waiting.
+    view.notifyLoadFinished();
+
+    // TODO: Emit a signal here and fallback to error system if signal wasn't handled by application?
+
+    GST_ELEMENT_ERROR(GST_ELEMENT_CAST(src), RESOURCE, FAILED, (NULL), ("%s", reason_str));
+
+    g_free (reason_str);
+}
+
 WPEView::WPEView(WebKitWebContext* web_context, GstWpeVideoSrc* src, GstGLContext* context, GstGLDisplay* display, int width, int height)
+  : m_src(src)
 {
 #ifdef G_OS_UNIX
 {
@@ -474,6 +493,7 @@ WPEView::WPEView(WebKitWebContext* web_context, GstWpeVideoSrc* src, GstGLContex
     g_signal_connect(webkit.view, "load-failed", G_CALLBACK(s_loadFailed), src);
     g_signal_connect(webkit.view, "load-failed-with-tls-errors", G_CALLBACK(s_loadFailedWithTLSErrors), src);
     g_signal_connect(webkit.view, "notify::estimated-load-progress", G_CALLBACK(s_loadProgressChanged), src);
+    g_signal_connect(webkit.view, "web-process-terminated", G_CALLBACK(s_webProcessCrashed), this);
 
     auto* settings = webkit_web_view_get_settings(webkit.view);
     webkit_settings_set_enable_webaudio(settings, TRUE);
diff --git a/subprojects/gst-plugins-bad/ext/wpe/WPEThreadedView.h b/subprojects/gst-plugins-bad/ext/wpe/WPEThreadedView.h
index 315cfbf47c..6e005827d7 100644
--- a/subprojects/gst-plugins-bad/ext/wpe/WPEThreadedView.h
+++ b/subprojects/gst-plugins-bad/ext/wpe/WPEThreadedView.h
@@ -59,6 +59,10 @@ public:
     void disconnectLoadFailedSignal();
     void waitLoadCompletion();
 
+    GstWpeVideoSrc *src() const { return m_src; }
+
+    void notifyLoadFinished();
+
 protected:
     void handleExportedImage(gpointer);
     void handleExportedBuffer(struct wpe_fdo_shm_exported_buffer*);
@@ -67,7 +71,6 @@ private:
     struct wpe_view_backend* backend() const;
     void frameComplete();
     void loadUriUnlocked(const gchar*);
-    void notifyLoadFinished();
 
     void releaseImage(gpointer);
     void releaseSHMBuffer(gpointer);
@@ -121,6 +124,7 @@ private:
         gulong extension_msg_sigid;
     } audio {0, 0};
 
+    GstWpeVideoSrc *m_src { nullptr };
 };
 
 class WPEContextThread {