source/lib/input.cpp

   1 /* Copyright (C) 2017 Wildfire Games.
   2  *
   3  * Permission is hereby granted, free of charge, to any person obtaining
   4  * a copy of this software and associated documentation files (the
   5  * "Software"), to deal in the Software without restriction, including
   6  * without limitation the rights to use, copy, modify, merge, publish,
   7  * distribute, sublicense, and/or sell copies of the Software, and to
   8  * permit persons to whom the Software is furnished to do so, subject to
   9  * the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included
  12  * in all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  17  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  18  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  19  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  20  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21  */
  22
  23 /*
  24  * SDL input redirector; dispatches to multiple handlers.
  25  */
  26
  27 #include "precompiled.h"
  28 #include "input.h"
  29
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32
  33 #include "lib/external_libraries/libsdl.h"
  34
  35 const size_t MAX_HANDLERS = 9;
  36 static InHandler handler_stack[MAX_HANDLERS];
  37 static size_t handler_stack_top = 0;
  38
  39 static std::list<SDL_Event_> priority_events;
  40
  41 void in_add_handler(InHandler handler)
  42 {
  43         ENSURE(handler);
  44
  45         if(handler_stack_top >= MAX_HANDLERS)
  46                 WARN_IF_ERR(ERR::LIMIT);
  47
  48         handler_stack[handler_stack_top++] = handler;
  49 }
  50
  51 void in_reset_handlers()
  52 {
  53         handler_stack_top = 0;
  54 }
  55
  56 // send ev to each handler until one returns IN_HANDLED
  57 void in_dispatch_event(const SDL_Event_* ev)
  58 {
  59         for(int i = (int)handler_stack_top-1; i >= 0; i--)
  60         {
  61                 ENSURE(handler_stack[i] && ev);
  62                 InReaction ret = handler_stack[i](ev);
  63                 // .. done, return
  64                 if(ret == IN_HANDLED)
  65                         return;
  66                 // .. next handler
  67                 else if(ret == IN_PASS)
  68                         continue;
  69                 // .. invalid return value
  70                 else
  71                         DEBUG_WARN_ERR(ERR::LOGIC);     // invalid handler return value
  72         }
  73 }
  74
  75 void in_push_priority_event(const SDL_Event_* event)
  76 {
  77         priority_events.push_back(*event);
  78 }
  79
  80 int in_poll_priority_event(SDL_Event_* event)
  81 {
  82         if (priority_events.empty())
  83                 return 0;
  84
  85         *event = priority_events.front();
  86         priority_events.pop_front();
  87         return 1;
  88 }
  89
  90 int in_poll_event(SDL_Event_* event)
  91 {
  92         return in_poll_priority_event(event) ? 1 : SDL_PollEvent(&event->ev);
  93 }