src/ui/base/x/selection_requestor.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/base/x/selection_requestor.h"
   6
   7 #include "base/message_loop/message_pump_x11.h"
   8 #include "base/run_loop.h"
   9 #include "ui/base/x/selection_utils.h"
  10 #include "ui/base/x/x11_util.h"
  11
  12 namespace ui {
  13
  14 namespace {
  15
  16 const char kChromeSelection[] = "CHROME_SELECTION";
  17
  18 const char* kAtomsToCache[] = {
  19   kChromeSelection,
  20   NULL
  21 };
  22
  23 }  // namespace
  24
  25 SelectionRequestor::SelectionRequestor(Display* x_display,
  26                                        Window x_window,
  27                                        Atom selection_name)
  28     : x_display_(x_display),
  29       x_window_(x_window),
  30       selection_name_(selection_name),
  31       atom_cache_(x_display_, kAtomsToCache) {
  32 }
  33
  34 SelectionRequestor::~SelectionRequestor() {}
  35
  36 bool SelectionRequestor::PerformBlockingConvertSelection(
  37     Atom target,
  38     scoped_refptr<base::RefCountedMemory>* out_data,
  39     size_t* out_data_bytes,
  40     size_t* out_data_items,
  41     Atom* out_type) {
  42   // The name of the property we're asking to be set on |x_window_|.
  43   Atom property_to_set = atom_cache_.GetAtom(kChromeSelection);
  44
  45   XConvertSelection(x_display_,
  46                     selection_name_,
  47                     target,
  48                     property_to_set,
  49                     x_window_,
  50                     CurrentTime);
  51
  52   // Now that we've thrown our message off to the X11 server, we block waiting
  53   // for a response.
  54   base::MessageLoopForUI* loop = base::MessageLoopForUI::current();
  55   base::MessageLoop::ScopedNestableTaskAllower allow_nested(loop);
  56   base::RunLoop run_loop;
  57
  58   PendingRequest pending_request(target, run_loop.QuitClosure());
  59   pending_requests_.push_back(&pending_request);
  60   run_loop.Run();
  61   DCHECK(!pending_requests_.empty());
  62   DCHECK_EQ(&pending_request, pending_requests_.back());
  63   pending_requests_.pop_back();
  64
  65   if (pending_request.returned_property != property_to_set)
  66     return false;
  67
  68   return ui::GetRawBytesOfProperty(x_window_, pending_request.returned_property,
  69                                    out_data, out_data_bytes, out_data_items,
  70                                    out_type);
  71 }
  72
  73 SelectionData SelectionRequestor::RequestAndWaitForTypes(
  74     const std::vector< ::Atom>& types) {
  75   for (std::vector< ::Atom>::const_iterator it = types.begin();
  76        it != types.end(); ++it) {
  77     scoped_refptr<base::RefCountedMemory> data;
  78     size_t data_bytes = 0;
  79     ::Atom type = None;
  80     if (PerformBlockingConvertSelection(*it,
  81                                         &data,
  82                                         &data_bytes,
  83                                         NULL,
  84                                         &type) &&
  85         type == *it) {
  86       return SelectionData(type, data);
  87     }
  88   }
  89
  90   return SelectionData();
  91 }
  92
  93 void SelectionRequestor::OnSelectionNotify(const XSelectionEvent& event) {
  94   // Find the PendingRequest for the corresponding XConvertSelection call. If
  95   // there are multiple pending requests on the same target, satisfy them in
  96   // FIFO order.
  97   PendingRequest* request_notified = NULL;
  98   if (selection_name_ == event.selection) {
  99     for (std::list<PendingRequest*>::iterator iter = pending_requests_.begin();
 100          iter != pending_requests_.end(); ++iter) {
 101       PendingRequest* request = *iter;
 102       if (request->returned)
 103         continue;
 104       if (request->target != event.target)
 105         continue;
 106       request_notified = request;
 107       break;
 108     }
 109   }
 110
 111   // This event doesn't correspond to any XConvertSelection calls that we
 112   // issued in PerformBlockingConvertSelection. This shouldn't happen, but any
 113   // client can send any message, so it can happen.
 114   if (!request_notified)
 115     return;
 116
 117   request_notified->returned_property = event.property;
 118   request_notified->returned = true;
 119   request_notified->quit_closure.Run();
 120 }
 121
 122 SelectionRequestor::PendingRequest::PendingRequest(Atom target,
 123                                                    base::Closure quit_closure)
 124     : target(target),
 125       quit_closure(quit_closure),
 126       returned_property(None),
 127       returned(false) {
 128 }
 129
 130 SelectionRequestor::PendingRequest::~PendingRequest() {
 131 }
 132
 133 }  // namespace ui