Line data Source code
1 : /* -*- Mode: C++; tab-width: 40; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 : /* This Source Code Form is subject to the terms of the Mozilla Public
3 : * License, v. 2.0. If a copy of the MPL was not distributed with this
4 : * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
5 :
6 : #include "nsX11ErrorHandler.h"
7 :
8 : #include "prenv.h"
9 : #include "nsXULAppAPI.h"
10 : #include "nsExceptionHandler.h"
11 : #include "nsDebug.h"
12 :
13 : #include "mozilla/X11Util.h"
14 : #include <X11/Xlib.h>
15 :
16 : #define BUFSIZE 2048 // What Xlib uses with XGetErrorDatabaseText
17 :
18 : extern "C" {
19 : int
20 0 : X11Error(Display *display, XErrorEvent *event) {
21 : // Get an indication of how long ago the request that caused the error was
22 : // made.
23 0 : unsigned long age = NextRequest(display) - event->serial;
24 :
25 : // Get a string to represent the request that caused the error.
26 0 : nsAutoCString message;
27 0 : if (event->request_code < 128) {
28 : // Core protocol request
29 0 : message.AppendInt(event->request_code);
30 : } else {
31 : // Extension request
32 :
33 : // man XSetErrorHandler says "the error handler should not call any
34 : // functions (directly or indirectly) on the display that will generate
35 : // protocol requests or that will look for input events" so we use another
36 : // temporary Display to request extension information. This assumes on
37 : // the DISPLAY environment variable has been set and matches what was used
38 : // to open |display|.
39 0 : Display *tmpDisplay = XOpenDisplay(nullptr);
40 0 : if (tmpDisplay) {
41 : int nExts;
42 0 : char** extNames = XListExtensions(tmpDisplay, &nExts);
43 : int first_error;
44 0 : if (extNames) {
45 0 : for (int i = 0; i < nExts; ++i) {
46 : int major_opcode, first_event;
47 0 : if (XQueryExtension(tmpDisplay, extNames[i],
48 : &major_opcode, &first_event, &first_error)
49 0 : && major_opcode == event->request_code) {
50 0 : message.Append(extNames[i]);
51 0 : message.Append('.');
52 0 : message.AppendInt(event->minor_code);
53 0 : break;
54 : }
55 : }
56 :
57 0 : XFreeExtensionList(extNames);
58 : }
59 0 : XCloseDisplay(tmpDisplay);
60 :
61 : #if (MOZ_WIDGET_GTK == 2)
62 : // GDK2 calls XCloseDevice the devices that it opened on startup, but
63 : // the XI protocol no longer ensures that the devices will still exist.
64 : // If they have been removed, then a BadDevice error results. Ignore
65 : // this error.
66 : if (message.EqualsLiteral("XInputExtension.4") &&
67 : event->error_code == first_error + 0) {
68 : return 0;
69 : }
70 : #endif
71 : }
72 : }
73 :
74 : char buffer[BUFSIZE];
75 0 : if (message.IsEmpty()) {
76 0 : buffer[0] = '\0';
77 : } else {
78 0 : XGetErrorDatabaseText(display, "XRequest", message.get(), "",
79 0 : buffer, sizeof(buffer));
80 : }
81 :
82 0 : nsAutoCString notes;
83 0 : if (buffer[0]) {
84 0 : notes.Append(buffer);
85 : } else {
86 0 : notes.AppendLiteral("Request ");
87 0 : notes.AppendInt(event->request_code);
88 0 : notes.Append('.');
89 0 : notes.AppendInt(event->minor_code);
90 : }
91 :
92 0 : notes.AppendLiteral(": ");
93 :
94 : // Get a string to describe the error.
95 0 : XGetErrorText(display, event->error_code, buffer, sizeof(buffer));
96 0 : notes.Append(buffer);
97 :
98 : // For requests where Xlib gets the reply synchronously, |age| will be 1
99 : // and the stack will include the function making the request. For
100 : // asynchronous requests, the current stack will often be unrelated to the
101 : // point of making the request, even if |age| is 1, but sometimes this may
102 : // help us count back to the point of the request. With XSynchronize on,
103 : // the stack will include the function making the request, even though
104 : // |age| will be 2 for asynchronous requests because XSynchronize is
105 : // implemented by an empty request from an XSync, which has not yet been
106 : // processed.
107 0 : if (age > 1) {
108 : // XSynchronize returns the previous "after function". If a second
109 : // XSynchronize call returns the same function after an enable call then
110 : // synchronization must have already been enabled.
111 0 : if (XSynchronize(display, True) == XSynchronize(display, False)) {
112 0 : notes.AppendLiteral("; sync");
113 : } else {
114 0 : notes.AppendLiteral("; ");
115 0 : notes.AppendInt(uint32_t(age));
116 0 : notes.AppendLiteral(" requests ago");
117 : }
118 : }
119 :
120 : #ifdef MOZ_CRASHREPORTER
121 0 : switch (XRE_GetProcessType()) {
122 : case GeckoProcessType_Default:
123 : case GeckoProcessType_Plugin:
124 : case GeckoProcessType_Content:
125 0 : CrashReporter::AppendAppNotesToCrashReport(notes);
126 0 : break;
127 : default:
128 : ; // crash report notes not supported.
129 : }
130 : #endif
131 :
132 : #ifdef DEBUG
133 : // The resource id is unlikely to be useful in a crash report without
134 : // context of other ids, but add it to the debug console output.
135 0 : notes.AppendLiteral("; id=0x");
136 0 : notes.AppendInt(uint32_t(event->resourceid), 16);
137 : #ifdef MOZ_X11
138 : // Actually, for requests where Xlib gets the reply synchronously,
139 : // MOZ_X_SYNC=1 will not be necessary, but we don't have a table to tell us
140 : // which requests get a synchronous reply.
141 0 : if (!PR_GetEnv("MOZ_X_SYNC")) {
142 0 : notes.AppendLiteral("\nRe-running with MOZ_X_SYNC=1 in the environment may give a more helpful backtrace.");
143 : }
144 : #endif
145 : #endif
146 :
147 0 : NS_RUNTIMEABORT(notes.get());
148 0 : return 0; // not reached
149 : }
150 : }
151 :
152 : void
153 0 : InstallX11ErrorHandler()
154 : {
155 0 : XSetErrorHandler(X11Error);
156 :
157 0 : Display *display = mozilla::DefaultXDisplay();
158 0 : NS_ASSERTION(display, "No X display");
159 0 : if (PR_GetEnv("MOZ_X_SYNC")) {
160 0 : XSynchronize(display, True);
161 : }
162 0 : }
|
