The Tor Browser / file comparison
comparison: gfx/src/X11Util.h
gfx/src/X11Util.h
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
equal
deleted
inserted
replaced
| -1:000000000000 | 0:2c447e943c18 |
|---|---|
| 1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- | |
| 2 * vim: sw=2 ts=8 et : | |
| 3 */ | |
| 4 /* This Source Code Form is subject to the terms of the Mozilla Public | |
| 5 * License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 6 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ | |
| 7 | |
| 8 #ifndef mozilla_X11Util_h | |
| 9 #define mozilla_X11Util_h | |
| 10 | |
| 11 // Utilities common to all X clients, regardless of UI toolkit. | |
| 12 | |
| 13 #if defined(MOZ_WIDGET_GTK) | |
| 14 # include <gdk/gdk.h> | |
| 15 # include <gdk/gdkx.h> | |
| 16 #elif defined(MOZ_WIDGET_QT) | |
| 17 #include "gfxQtPlatform.h" | |
| 18 #undef CursorShape | |
| 19 # include <X11/Xlib.h> | |
| 20 #else | |
| 21 # error Unknown toolkit | |
| 22 #endif | |
| 23 | |
| 24 #include <string.h> // for memset | |
| 25 #include "gfxCore.h" // for NS_GFX | |
| 26 #include "mozilla/Scoped.h" // for SCOPED_TEMPLATE | |
| 27 | |
| 28 namespace mozilla { | |
| 29 | |
| 30 /** | |
| 31 * Return the default X Display created and used by the UI toolkit. | |
| 32 */ | |
| 33 inline Display* | |
| 34 DefaultXDisplay() | |
| 35 { | |
| 36 #if defined(MOZ_WIDGET_GTK) | |
| 37 return GDK_DISPLAY_XDISPLAY(gdk_display_get_default()); | |
| 38 #elif defined(MOZ_WIDGET_QT) | |
| 39 return gfxQtPlatform::GetXDisplay(); | |
| 40 #endif | |
| 41 } | |
| 42 | |
| 43 /** | |
| 44 * Sets *aVisual to point to aDisplay's Visual struct corresponding to | |
| 45 * aVisualID, and *aDepth to its depth. When aVisualID is None, these are set | |
| 46 * to nullptr and 0 respectively. Both out-parameter pointers are assumed | |
| 47 * non-nullptr. | |
| 48 */ | |
| 49 void | |
| 50 FindVisualAndDepth(Display* aDisplay, VisualID aVisualID, | |
| 51 Visual** aVisual, int* aDepth); | |
| 52 | |
| 53 | |
| 54 /** | |
| 55 * Ensure that all X requests have been processed. | |
| 56 * | |
| 57 * This is similar to XSync, but doesn't need a round trip if the previous | |
| 58 * request was synchronous or if events have been received since the last | |
| 59 * request. Subsequent FinishX calls will be noops if there have been no | |
| 60 * intermediate requests. | |
| 61 */ | |
| 62 | |
| 63 void | |
| 64 FinishX(Display* aDisplay); | |
| 65 | |
| 66 /** | |
| 67 * Invoke XFree() on a pointer to memory allocated by Xlib (if the | |
| 68 * pointer is nonnull) when this class goes out of scope. | |
| 69 */ | |
| 70 template <typename T> | |
| 71 struct ScopedXFreePtrTraits | |
| 72 { | |
| 73 typedef T *type; | |
| 74 static T *empty() { return nullptr; } | |
| 75 static void release(T *ptr) { if (ptr != nullptr) XFree(ptr); } | |
| 76 }; | |
| 77 SCOPED_TEMPLATE(ScopedXFree, ScopedXFreePtrTraits) | |
| 78 | |
| 79 /** | |
| 80 * On construction, set a graceful X error handler that doesn't crash the application and records X errors. | |
| 81 * On destruction, restore the X error handler to what it was before construction. | |
| 82 * | |
| 83 * The SyncAndGetError() method allows to know whether a X error occurred, optionally allows to get the full XErrorEvent, | |
| 84 * and resets the recorded X error state so that a single X error will be reported only once. | |
| 85 * | |
| 86 * Nesting is correctly handled: multiple nested ScopedXErrorHandler's don't interfere with each other's state. However, | |
| 87 * if SyncAndGetError is not called on the nested ScopedXErrorHandler, then any X errors caused by X calls made while the nested | |
| 88 * ScopedXErrorHandler was in place may then be caught by the other ScopedXErrorHandler. This is just a result of X being | |
| 89 * asynchronous and us not doing any implicit syncing: the only method in this class what causes syncing is SyncAndGetError(). | |
| 90 * | |
| 91 * This class is not thread-safe at all. It is assumed that only one thread is using any ScopedXErrorHandler's. Given that it's | |
| 92 * not used on Mac, it should be easy to make it thread-safe by using thread-local storage with __thread. | |
| 93 */ | |
| 94 class NS_GFX ScopedXErrorHandler | |
| 95 { | |
| 96 public: | |
| 97 // trivial wrapper around XErrorEvent, just adding ctor initializing by zero. | |
| 98 struct ErrorEvent | |
| 99 { | |
| 100 XErrorEvent mError; | |
| 101 | |
| 102 ErrorEvent() | |
| 103 { | |
| 104 memset(this, 0, sizeof(ErrorEvent)); | |
| 105 } | |
| 106 }; | |
| 107 | |
| 108 private: | |
| 109 | |
| 110 // this ScopedXErrorHandler's ErrorEvent object | |
| 111 ErrorEvent mXError; | |
| 112 | |
| 113 // static pointer for use by the error handler | |
| 114 static ErrorEvent* sXErrorPtr; | |
| 115 | |
| 116 // what to restore sXErrorPtr to on destruction | |
| 117 ErrorEvent* mOldXErrorPtr; | |
| 118 | |
| 119 // what to restore the error handler to on destruction | |
| 120 int (*mOldErrorHandler)(Display *, XErrorEvent *); | |
| 121 | |
| 122 public: | |
| 123 | |
| 124 static int | |
| 125 ErrorHandler(Display *, XErrorEvent *ev); | |
| 126 | |
| 127 ScopedXErrorHandler(); | |
| 128 | |
| 129 ~ScopedXErrorHandler(); | |
| 130 | |
| 131 /** \returns true if a X error occurred since the last time this method was called on this ScopedXErrorHandler object, | |
| 132 * or since the creation of this ScopedXErrorHandler object if this method was never called on it. | |
| 133 * | |
| 134 * \param ev this optional parameter, if set, will be filled with the XErrorEvent object. If multiple errors occurred, | |
| 135 * the first one will be returned. | |
| 136 */ | |
| 137 bool SyncAndGetError(Display *dpy, XErrorEvent *ev = nullptr); | |
| 138 }; | |
| 139 | |
| 140 } // namespace mozilla | |
| 141 | |
| 142 #endif // mozilla_X11Util_h |
