lib/widget/mouse.c

   1 /*
   2    Widgets for the Midnight Commander
   3
   4    Copyright (C) 1994-2016
   5    Free Software Foundation, Inc.
   6
   7    Authors:
   8    Human beings.
   9
  10    This file is part of the Midnight Commander.
  11
  12    The Midnight Commander is free software: you can redistribute it
  13    and/or modify it under the terms of the GNU General Public License as
  14    published by the Free Software Foundation, either version 3 of the License,
  15    or (at your option) any later version.
  16
  17    The Midnight Commander is distributed in the hope that it will be useful,
  18    but WITHOUT ANY WARRANTY; without even the implied warranty of
  19    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20    GNU General Public License for more details.
  21
  22    You should have received a copy of the GNU General Public License
  23    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  24  */
  25
  26 /** \file mouse.c
  27  *  \brief Header: High-level mouse API
  28  */
  29
  30 #include <config.h>
  31
  32 #include "lib/global.h"
  33 #include "lib/widget.h"
  34
  35 #include "lib/widget/mouse.h"
  36
  37 /*** global variables ****************************************************************************/
  38
  39 /*** file scope macro definitions ****************************************************************/
  40
  41 /*** file scope type declarations ****************************************************************/
  42
  43 /*** file scope variables ************************************************************************/
  44
  45 /* --------------------------------------------------------------------------------------------- */
  46 /*** file scope functions ************************************************************************/
  47 /* --------------------------------------------------------------------------------------------- */
  48
  49 /**
  50  * Constructs a mouse event structure.
  51  *
  52  * It receives a Gpm_Event event and translates it into a higher level protocol.
  53  *
  54  * Tip: for details on the C mouse API, see MC's lib/tty/mouse.h,
  55  * or GPM's excellent 'info' manual:
  56  *
  57  *    http://www.fifi.org/cgi-bin/info2www?(gpm)Event+Types
  58  */
  59 static void
  60 init_mouse_event (mouse_event_t * event, mouse_msg_t msg, const Gpm_Event * global_gpm,
  61                   const Widget * w)
  62 {
  63     event->msg = msg;
  64     event->x = global_gpm->x - w->x - 1;        /* '-1' because Gpm_Event is 1-based. */
  65     event->y = global_gpm->y - w->y - 1;
  66     event->count = global_gpm->type & (GPM_SINGLE | GPM_DOUBLE | GPM_TRIPLE);
  67     event->buttons = global_gpm->buttons;
  68     event->result.abort = FALSE;
  69     event->result.repeat = FALSE;
  70 }
  71
  72 /* --------------------------------------------------------------------------------------------- */
  73 /*** public functions ****************************************************************************/
  74 /* --------------------------------------------------------------------------------------------- */
  75
  76 /**
  77  * Translate GPM event to high-level event,
  78  *
  79  * @param w Widget object
  80  * @param event GPM event
  81  * @param click whether mouse click was raised or not
  82  *
  83  * @return high level mouse event
  84  */
  85 mouse_event_t
  86 mouse_translate_event (Widget * w, Gpm_Event * event, gboolean * click)
  87 {
  88     gboolean in_widget;
  89     mouse_msg_t msg = MSG_MOUSE_NONE;
  90     mouse_event_t local;
  91
  92     /*
  93      * Very special widgets may want to control area outside their bounds.
  94      * For such widgets you will have to turn on the 'forced_capture' flag.
  95      * You'll also need, in your mouse handler, to inform the system of
  96      * events you want to pass on by setting 'event->result.abort' to TRUE.
  97      */
  98     in_widget = w->mouse.forced_capture || mouse_global_in_widget (event, w);
  99
 100     *click = FALSE;
 101
 102     if ((event->type & GPM_DOWN) != 0)
 103     {
 104         if (in_widget)
 105         {
 106             if ((event->buttons & GPM_B_UP) != 0)
 107                 msg = MSG_MOUSE_SCROLL_UP;
 108             else if ((event->buttons & GPM_B_DOWN) != 0)
 109                 msg = MSG_MOUSE_SCROLL_DOWN;
 110             else
 111             {
 112                 /* Handle normal buttons: anything but the mouse wheel's.
 113                  *
 114                  * (Note that turning on capturing for the mouse wheel
 115                  * buttons doesn't make sense as they don't generate a
 116                  * mouse_up event, which means we'd never get uncaptured.)
 117                  */
 118                 w->mouse.capture = TRUE;
 119                 msg = MSG_MOUSE_DOWN;
 120
 121                 w->mouse.last_buttons_down = event->buttons;
 122             }
 123         }
 124     }
 125     else if ((event->type & GPM_UP) != 0)
 126     {
 127         /* We trigger the mouse_up event even when !in_widget. That's
 128          * because, for example, a paint application should stop drawing
 129          * lines when the button is released even outside the canvas. */
 130         if (w->mouse.capture)
 131         {
 132             w->mouse.capture = FALSE;
 133             msg = MSG_MOUSE_UP;
 134
 135             if (in_widget)
 136                 *click = !w->mouse.was_drag;
 137
 138             /*
 139              * When using xterm, event->buttons reports the buttons' state
 140              * after the event occurred (meaning that event->buttons is zero,
 141              * because the mouse button is now released). When using GPM,
 142              * however, that field reports the button(s) that was released.
 143              *
 144              * The following makes xterm behave effectively like GPM:
 145              */
 146             if (event->buttons == 0)
 147                 event->buttons = w->mouse.last_buttons_down;
 148         }
 149     }
 150     else if ((event->type & GPM_DRAG) != 0)
 151     {
 152         if (w->mouse.capture)
 153             msg = MSG_MOUSE_DRAG;
 154     }
 155     else if ((event->type & GPM_MOVE) != 0)
 156     {
 157         if (in_widget)
 158             msg = MSG_MOUSE_MOVE;
 159     }
 160
 161     if (msg != MSG_MOUSE_NONE)
 162         /* Remember the current state for next event. */
 163         w->mouse.was_drag = ((event->type & GPM_DRAG) != 0);
 164
 165     init_mouse_event (&local, msg, event, w);
 166
 167     return local;
 168 }
 169
 170 /* --------------------------------------------------------------------------------------------- */
 171
 172 /**
 173  * Call widget mouse handler to process high-level mouse event.
 174  *
 175  * @param w Widget object
 176  * @param high level mouse event
 177  * @param click whether mouse click was raised or not
 178  *
 179  * @return result of mouse event handling
 180  */
 181 int
 182 mouse_process_event (Widget * w, mouse_event_t * event, gboolean click)
 183 {
 184     int ret = MOU_UNHANDLED;
 185
 186     if (event->msg != MSG_MOUSE_NONE)
 187     {
 188         w->mouse_callback (w, event->msg, event);
 189         if (click)
 190             w->mouse_callback (w, MSG_MOUSE_CLICK, event);
 191
 192         if (!event->result.abort)
 193             ret = event->result.repeat ? MOU_REPEAT : MOU_NORMAL;
 194     }
 195
 196     return ret;
 197 }
 198
 199 /* --------------------------------------------------------------------------------------------- */