app/gtk_signal.h

   1 // Copyright (c) 2010 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 #ifndef APP_GTK_SIGNAL_H_
   6 #define APP_GTK_SIGNAL_H_
   7 #pragma once
   8
   9 typedef void* gpointer;
  10 typedef struct _GtkWidget GtkWidget;
  11
  12 // At the time of writing this, there were two common ways of binding our C++
  13 // code to the gobject C system. We either defined a whole bunch of "static
  14 // MethodThunk()" which just called nonstatic Method()s on a class (which hurt
  15 // readability of the headers and signal connection code) OR we declared
  16 // "static Method()" and passed in the current object as the gpointer (and hurt
  17 // readability in the implementation by having "context->" before every
  18 // variable).
  19
  20 // The hopeful result of using these macros is that the code will be more
  21 // readable and regular. There shouldn't be a bunch of static Thunks visible in
  22 // the headers and the implementations shouldn't be filled with "context->"
  23 // de-references.
  24
  25 #define CHROMEG_CALLBACK_0(CLASS, RETURN, METHOD, SENDER)           \
  26   static RETURN METHOD ## Thunk(SENDER sender, gpointer userdata) { \
  27     return reinterpret_cast<CLASS*>(userdata)->METHOD(sender);      \
  28   }                                                                 \
  29                                                                     \
  30   virtual RETURN METHOD(SENDER);
  31
  32 #define CHROMEG_CALLBACK_1(CLASS, RETURN, METHOD, SENDER, ARG1)     \
  33   static RETURN METHOD ## Thunk(SENDER sender, ARG1 one,            \
  34                                 gpointer userdata) {                \
  35     return reinterpret_cast<CLASS*>(userdata)->METHOD(sender, one); \
  36   }                                                                 \
  37                                                                     \
  38   virtual RETURN METHOD(SENDER, ARG1);
  39
  40 #define CHROMEG_CALLBACK_2(CLASS, RETURN, METHOD, SENDER, ARG1, ARG2)    \
  41   static RETURN METHOD ## Thunk(SENDER sender, ARG1 one, ARG2 two,       \
  42                                 gpointer userdata) {                     \
  43     return reinterpret_cast<CLASS*>(userdata)->METHOD(sender, one, two); \
  44   }                                                                      \
  45                                                                          \
  46   virtual RETURN METHOD(SENDER, ARG1, ARG2);
  47
  48 #define CHROMEG_CALLBACK_3(CLASS, RETURN, METHOD, SENDER, ARG1, ARG2, ARG3) \
  49   static RETURN METHOD ## Thunk(SENDER sender, ARG1 one, ARG2 two,          \
  50                                 ARG3 three, gpointer userdata) {            \
  51     return reinterpret_cast<CLASS*>(userdata)->                             \
  52         METHOD(sender, one, two, three);                                    \
  53   }                                                                         \
  54                                                                             \
  55   virtual RETURN METHOD(SENDER, ARG1, ARG2, ARG3);
  56
  57 #define CHROMEG_CALLBACK_4(CLASS, RETURN, METHOD, SENDER, ARG1, ARG2, ARG3, \
  58                            ARG4)                                            \
  59   static RETURN METHOD ## Thunk(SENDER sender, ARG1 one, ARG2 two,          \
  60                                 ARG3 three, ARG4 four,                      \
  61                                 gpointer userdata) {                        \
  62     return reinterpret_cast<CLASS*>(userdata)->                             \
  63         METHOD(sender, one, two, three, four);                              \
  64   }                                                                         \
  65                                                                             \
  66   virtual RETURN METHOD(SENDER, ARG1, ARG2, ARG3, ARG4);
  67
  68 #define CHROMEG_CALLBACK_5(CLASS, RETURN, METHOD, SENDER, ARG1, ARG2, ARG3, \
  69                            ARG4, ARG5)                                      \
  70   static RETURN METHOD ## Thunk(SENDER sender, ARG1 one, ARG2 two,          \
  71                                 ARG3 three, ARG4 four, ARG5 five,           \
  72                                 gpointer userdata) {                        \
  73     return reinterpret_cast<CLASS*>(userdata)->                             \
  74         METHOD(sender, one, two, three, four, five);                        \
  75   }                                                                         \
  76                                                                             \
  77   virtual RETURN METHOD(SENDER, ARG1, ARG2, ARG3, ARG4, ARG5);
  78
  79 #define CHROMEG_CALLBACK_6(CLASS, RETURN, METHOD, SENDER, ARG1, ARG2, ARG3, \
  80                            ARG4, ARG5, ARG6)                                \
  81   static RETURN METHOD ## Thunk(SENDER sender, ARG1 one, ARG2 two,          \
  82                                 ARG3 three, ARG4 four, ARG5 five,           \
  83                                 ARG6 six, gpointer userdata) {              \
  84     return reinterpret_cast<CLASS*>(userdata)->                             \
  85         METHOD(sender, one, two, three, four, five, six);                   \
  86   }                                                                         \
  87                                                                             \
  88   virtual RETURN METHOD(SENDER, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6);
  89
  90 // These macros handle the common case where the sender object will be a
  91 // GtkWidget*.
  92 #define CHROMEGTK_CALLBACK_0(CLASS, RETURN, METHOD) \
  93   CHROMEG_CALLBACK_0(CLASS, RETURN, METHOD, GtkWidget*);
  94
  95 #define CHROMEGTK_CALLBACK_1(CLASS, RETURN, METHOD, ARG1) \
  96   CHROMEG_CALLBACK_1(CLASS, RETURN, METHOD, GtkWidget*, ARG1);
  97
  98 #define CHROMEGTK_CALLBACK_2(CLASS, RETURN, METHOD, ARG1, ARG2) \
  99   CHROMEG_CALLBACK_2(CLASS, RETURN, METHOD, GtkWidget*, ARG1, ARG2);
 100
 101 #define CHROMEGTK_CALLBACK_3(CLASS, RETURN, METHOD, ARG1, ARG2, ARG3) \
 102   CHROMEG_CALLBACK_3(CLASS, RETURN, METHOD, GtkWidget*, ARG1, ARG2, ARG3);
 103
 104 #define CHROMEGTK_CALLBACK_4(CLASS, RETURN, METHOD, ARG1, ARG2, ARG3, ARG4) \
 105   CHROMEG_CALLBACK_4(CLASS, RETURN, METHOD, GtkWidget*, ARG1, ARG2, ARG3, ARG4);
 106
 107 #define CHROMEGTK_CALLBACK_5(CLASS, RETURN, METHOD, ARG1, ARG2, ARG3, ARG4, \
 108                              ARG5)                                          \
 109   CHROMEG_CALLBACK_5(CLASS, RETURN, METHOD, GtkWidget*, ARG1, ARG2, ARG3,   \
 110                      ARG4, ARG5);
 111
 112 #define CHROMEGTK_CALLBACK_6(CLASS, RETURN, METHOD, ARG1, ARG2, ARG3, ARG4, \
 113                              ARG5, ARG6)                                    \
 114   CHROMEG_CALLBACK_6(CLASS, RETURN, METHOD, GtkWidget*, ARG1, ARG2, ARG3,   \
 115                      ARG4, ARG5, ARG6);
 116
 117 #endif  // APP_GTK_SIGNAL_H_