The Tor Browser: widget/gtk/nsIdleServiceGTK.cpp@ac0c01689b40

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

     1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

     2 /* vim:expandtab:shiftwidth=4:tabstop=4:

     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/. */

     8 #include <gtk/gtk.h>

    10 #include "nsIdleServiceGTK.h"

    11 #include "nsIServiceManager.h"

    12 #include "nsDebug.h"

    13 #include "prlink.h"

    14 #include "prlog.h"

    16 #ifdef PR_LOGGING

    17 static PRLogModuleInfo* sIdleLog = nullptr;

    18 #endif

    20 typedef bool (*_XScreenSaverQueryExtension_fn)(Display* dpy, int* event_base,

    21                                                  int* error_base);

    23 typedef XScreenSaverInfo* (*_XScreenSaverAllocInfo_fn)(void);

    25 typedef void (*_XScreenSaverQueryInfo_fn)(Display* dpy, Drawable drw,

    26                                           XScreenSaverInfo *info);

    28 static bool sInitialized = false;

    29 static _XScreenSaverQueryExtension_fn _XSSQueryExtension = nullptr;

    30 static _XScreenSaverAllocInfo_fn _XSSAllocInfo = nullptr;

    31 static _XScreenSaverQueryInfo_fn _XSSQueryInfo = nullptr;

    33 NS_IMPL_ISUPPORTS_INHERITED0(nsIdleServiceGTK, nsIdleService)

    35 static void Initialize()

    36 {

    37     // This will leak - See comments in ~nsIdleServiceGTK().

    38     PRLibrary* xsslib = PR_LoadLibrary("libXss.so.1");

    39     if (!xsslib) // ouch.

    40     {

    41 #ifdef PR_LOGGING

    42         PR_LOG(sIdleLog, PR_LOG_WARNING, ("Failed to find libXss.so!\n"));

    43 #endif

    44         return;

    45     }

    47     _XSSQueryExtension = (_XScreenSaverQueryExtension_fn)

    48         PR_FindFunctionSymbol(xsslib, "XScreenSaverQueryExtension");

    49     _XSSAllocInfo = (_XScreenSaverAllocInfo_fn)

    50         PR_FindFunctionSymbol(xsslib, "XScreenSaverAllocInfo");

    51     _XSSQueryInfo = (_XScreenSaverQueryInfo_fn)

    52         PR_FindFunctionSymbol(xsslib, "XScreenSaverQueryInfo");

    53 #ifdef PR_LOGGING

    54     if (!_XSSQueryExtension)

    55         PR_LOG(sIdleLog, PR_LOG_WARNING, ("Failed to get XSSQueryExtension!\n"));

    56     if (!_XSSAllocInfo)

    57         PR_LOG(sIdleLog, PR_LOG_WARNING, ("Failed to get XSSAllocInfo!\n"));

    58     if (!_XSSQueryInfo)

    59         PR_LOG(sIdleLog, PR_LOG_WARNING, ("Failed to get XSSQueryInfo!\n"));

    60 #endif

    62     sInitialized = true;

    63 }

    65 nsIdleServiceGTK::nsIdleServiceGTK()

    66     : mXssInfo(nullptr)

    67 {

    68 #ifdef PR_LOGGING

    69     if (!sIdleLog)

    70         sIdleLog = PR_NewLogModule("nsIIdleService");

    71 #endif

    73     Initialize();

    74 }

    76 nsIdleServiceGTK::~nsIdleServiceGTK()

    77 {

    78     if (mXssInfo)

    79         XFree(mXssInfo);

    81 // It is not safe to unload libXScrnSaver until each display is closed because

    82 // the library registers callbacks through XESetCloseDisplay (Bug 397607).

    83 // (Also the library and its functions are scoped for the file not the object.)

    84 #if 0

    85     if (xsslib) {

    86         PR_UnloadLibrary(xsslib);

    87         xsslib = nullptr;

    88     }

    89 #endif

    90 }

    92 bool

    93 nsIdleServiceGTK::PollIdleTime(uint32_t *aIdleTime)

    94 {

    95     if (!sInitialized) {

    96         // For some reason, we could not find xscreensaver.

    97         return false;

    98     }

   100     // Ask xscreensaver about idle time:

   101     *aIdleTime = 0;

   103     // We might not have a display (cf. in xpcshell)

   104     Display *dplay = GDK_DISPLAY_XDISPLAY(gdk_display_get_default());

   105     if (!dplay) {

   106 #ifdef PR_LOGGING

   107         PR_LOG(sIdleLog, PR_LOG_WARNING, ("No display found!\n"));

   108 #endif

   109         return false;

   110     }

   112     if (!_XSSQueryExtension || !_XSSAllocInfo || !_XSSQueryInfo) {

   113         return false;

   114     }

   116     int event_base, error_base;

   117     if (_XSSQueryExtension(dplay, &event_base, &error_base))

   118     {

   119         if (!mXssInfo)

   120             mXssInfo = _XSSAllocInfo();

   121         if (!mXssInfo)

   122             return false;

   123         _XSSQueryInfo(dplay, GDK_ROOT_WINDOW(), mXssInfo);

   124         *aIdleTime = mXssInfo->idle;

   125         return true;

   126     }

   127     // If we get here, we couldn't get to XScreenSaver:

   128 #ifdef PR_LOGGING

   129     PR_LOG(sIdleLog, PR_LOG_WARNING, ("XSSQueryExtension returned false!\n"));

   130 #endif

   131     return false;

   132 }

   134 bool

   135 nsIdleServiceGTK::UsePollMode()

   136 {

   137     return sInitialized;

   138 }

The Tor Browser / file revision

widget/gtk/nsIdleServiceGTK.cpp@ac0c01689b40

widget/gtk/nsIdleServiceGTK.cpp