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