michael@0: /* -*- Mode: C++; tab-width: 40; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsX11ErrorHandler.h"
michael@0: 
michael@0: #include "prenv.h"
michael@0: #include "nsXULAppAPI.h"
michael@0: #include "nsExceptionHandler.h"
michael@0: #include "nsDebug.h"
michael@0: 
michael@0: #include "mozilla/X11Util.h"
michael@0: #include <X11/Xlib.h>
michael@0: 
michael@0: #define BUFSIZE 2048 // What Xlib uses with XGetErrorDatabaseText
michael@0: 
michael@0: extern "C" {
michael@0: static int
michael@0: X11Error(Display *display, XErrorEvent *event) {
michael@0:   // Get an indication of how long ago the request that caused the error was
michael@0:   // made.
michael@0:   unsigned long age = NextRequest(display) - event->serial;
michael@0: 
michael@0:   // Get a string to represent the request that caused the error.
michael@0:   nsAutoCString message;
michael@0:   if (event->request_code < 128) {
michael@0:     // Core protocol request
michael@0:     message.AppendInt(event->request_code);
michael@0:   } else {
michael@0:     // Extension request
michael@0: 
michael@0:     // man XSetErrorHandler says "the error handler should not call any
michael@0:     // functions (directly or indirectly) on the display that will generate
michael@0:     // protocol requests or that will look for input events" so we use another
michael@0:     // temporary Display to request extension information.  This assumes on
michael@0:     // the DISPLAY environment variable has been set and matches what was used
michael@0:     // to open |display|.
michael@0:     Display *tmpDisplay = XOpenDisplay(nullptr);
michael@0:     if (tmpDisplay) {
michael@0:       int nExts;
michael@0:       char** extNames = XListExtensions(tmpDisplay, &nExts);
michael@0:       int first_error;
michael@0:       if (extNames) {
michael@0:         for (int i = 0; i < nExts; ++i) {
michael@0:           int major_opcode, first_event;
michael@0:           if (XQueryExtension(tmpDisplay, extNames[i],
michael@0:                               &major_opcode, &first_event, &first_error)
michael@0:               && major_opcode == event->request_code) {
michael@0:             message.Append(extNames[i]);
michael@0:             message.Append('.');
michael@0:             message.AppendInt(event->minor_code);
michael@0:             break;
michael@0:           }
michael@0:         }
michael@0: 
michael@0:         XFreeExtensionList(extNames);
michael@0:       }
michael@0:       XCloseDisplay(tmpDisplay);
michael@0: 
michael@0: #if (MOZ_WIDGET_GTK == 2)
michael@0:       // GDK2 calls XCloseDevice the devices that it opened on startup, but
michael@0:       // the XI protocol no longer ensures that the devices will still exist.
michael@0:       // If they have been removed, then a BadDevice error results.  Ignore
michael@0:       // this error.
michael@0:       if (message.EqualsLiteral("XInputExtension.4") &&
michael@0:           event->error_code == first_error + 0) {
michael@0:         return 0;
michael@0:       }
michael@0: #endif
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   char buffer[BUFSIZE];
michael@0:   if (message.IsEmpty()) {
michael@0:     buffer[0] = '\0';
michael@0:   } else {
michael@0:     XGetErrorDatabaseText(display, "XRequest", message.get(), "",
michael@0:                           buffer, sizeof(buffer));
michael@0:   }
michael@0: 
michael@0:   nsAutoCString notes;
michael@0:   if (buffer[0]) {
michael@0:     notes.Append(buffer);
michael@0:   } else {
michael@0:     notes.Append("Request ");
michael@0:     notes.AppendInt(event->request_code);
michael@0:     notes.Append('.');
michael@0:     notes.AppendInt(event->minor_code);
michael@0:   }
michael@0: 
michael@0:   notes.Append(": ");
michael@0: 
michael@0:   // Get a string to describe the error.
michael@0:   XGetErrorText(display, event->error_code, buffer, sizeof(buffer));
michael@0:   notes.Append(buffer);
michael@0: 
michael@0:   // For requests where Xlib gets the reply synchronously, |age| will be 1
michael@0:   // and the stack will include the function making the request.  For
michael@0:   // asynchronous requests, the current stack will often be unrelated to the
michael@0:   // point of making the request, even if |age| is 1, but sometimes this may
michael@0:   // help us count back to the point of the request.  With XSynchronize on,
michael@0:   // the stack will include the function making the request, even though
michael@0:   // |age| will be 2 for asynchronous requests because XSynchronize is
michael@0:   // implemented by an empty request from an XSync, which has not yet been
michael@0:   // processed.
michael@0:   if (age > 1) {
michael@0:     // XSynchronize returns the previous "after function".  If a second
michael@0:     // XSynchronize call returns the same function after an enable call then
michael@0:     // synchronization must have already been enabled.
michael@0:     if (XSynchronize(display, True) == XSynchronize(display, False)) {
michael@0:       notes.Append("; sync");
michael@0:     } else {
michael@0:       notes.Append("; ");
michael@0:       notes.AppendInt(uint32_t(age));
michael@0:       notes.Append(" requests ago");
michael@0:     }
michael@0:   }
michael@0: 
michael@0: #ifdef MOZ_CRASHREPORTER
michael@0:   switch (XRE_GetProcessType()) {
michael@0:   case GeckoProcessType_Default:
michael@0:   case GeckoProcessType_Plugin:
michael@0:   case GeckoProcessType_Content:
michael@0:     CrashReporter::AppendAppNotesToCrashReport(notes);
michael@0:     break;
michael@0:   default: 
michael@0:     ; // crash report notes not supported.
michael@0:   }
michael@0: #endif
michael@0: 
michael@0: #ifdef DEBUG
michael@0:   // The resource id is unlikely to be useful in a crash report without
michael@0:   // context of other ids, but add it to the debug console output.
michael@0:   notes.Append("; id=0x");
michael@0:   notes.AppendInt(uint32_t(event->resourceid), 16);
michael@0: #ifdef MOZ_X11
michael@0:   // Actually, for requests where Xlib gets the reply synchronously,
michael@0:   // MOZ_X_SYNC=1 will not be necessary, but we don't have a table to tell us
michael@0:   // which requests get a synchronous reply.
michael@0:   if (!PR_GetEnv("MOZ_X_SYNC")) {
michael@0:     notes.Append("\nRe-running with MOZ_X_SYNC=1 in the environment may give a more helpful backtrace.");
michael@0:   }
michael@0: #endif
michael@0: #endif
michael@0: 
michael@0: #ifdef MOZ_WIDGET_QT
michael@0:   // We should not abort here if MOZ_X_SYNC is not set
michael@0:   // until http://bugreports.qt.nokia.com/browse/QTBUG-4042
michael@0:   // not fixed, just print error value
michael@0:   if (!PR_GetEnv("MOZ_X_SYNC")) {
michael@0:     fprintf(stderr, "XError: %s\n", notes.get());
michael@0:     return 0; // temporary workaround for bug 161472
michael@0:   }
michael@0: #endif
michael@0: 
michael@0:   NS_RUNTIMEABORT(notes.get());
michael@0:   return 0; // not reached
michael@0: }
michael@0: }
michael@0: 
michael@0: void
michael@0: InstallX11ErrorHandler()
michael@0: {
michael@0:   XSetErrorHandler(X11Error);
michael@0: 
michael@0:   Display *display = mozilla::DefaultXDisplay();
michael@0:   NS_ASSERTION(display, "No X display");
michael@0:   if (PR_GetEnv("MOZ_X_SYNC")) {
michael@0:     XSynchronize(display, True);
michael@0:   }
michael@0: }