src/w32xfns.c

   1 /* Functions taken directly from X sources for use with the Microsoft Windows API.
   2    Copyright (C) 1989, 1992-1995, 1999, 2001-2017 Free Software
   3    Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software: you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation, either version 3 of the License, or (at
  10 your option) any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include <config.h>
  21 #include <signal.h>
  22 #include <stdio.h>
  23 #include <windows.h>
  24 #include <windowsx.h>
  25
  26 #include "lisp.h"
  27 #include "frame.h"
  28 #include "w32term.h"
  29
  30 #define myalloc(cb) GlobalAllocPtr (GPTR, cb)
  31 #define myfree(lp) GlobalFreePtr (lp)
  32
  33 CRITICAL_SECTION critsect;
  34
  35 #ifdef WINDOWSNT
  36 extern HANDLE keyboard_handle;
  37 #endif /* WINDOWSNT */
  38
  39 HANDLE input_available = NULL;
  40 HANDLE interrupt_handle = NULL;
  41
  42 void
  43 init_crit (void)
  44 {
  45   InitializeCriticalSection (&critsect);
  46
  47   /* For safety, input_available should only be reset by get_next_msg
  48      when the input queue is empty, so make it a manual reset event. */
  49   input_available = CreateEvent (NULL, TRUE, FALSE, NULL);
  50
  51 #ifdef WINDOWSNT
  52   keyboard_handle = input_available;
  53 #endif /* WINDOWSNT */
  54
  55   /* interrupt_handle is signaled when quit (C-g) is detected, so that
  56      blocking system calls can be interrupted.  We make it a manual
  57      reset event, so that if we should ever have multiple threads
  58      performing system calls, they will all be interrupted (I'm guessing
  59      that would the right response).  Note that we use PulseEvent to
  60      signal this event, so that it never remains signaled.  */
  61   interrupt_handle = CreateEvent (NULL, TRUE, FALSE, NULL);
  62 }
  63
  64 void
  65 delete_crit (void)
  66 {
  67   DeleteCriticalSection (&critsect);
  68
  69   if (input_available)
  70     {
  71       CloseHandle (input_available);
  72       input_available = NULL;
  73     }
  74   if (interrupt_handle)
  75     {
  76       CloseHandle (interrupt_handle);
  77       interrupt_handle = NULL;
  78     }
  79 }
  80
  81 void
  82 signal_quit (void)
  83 {
  84   /* Make sure this event never remains signaled; if the main thread
  85      isn't in a blocking call, then this should do nothing.  */
  86   PulseEvent (interrupt_handle);
  87 }
  88
  89 void
  90 select_palette (struct frame *f, HDC hdc)
  91 {
  92   struct w32_display_info *display_info = FRAME_DISPLAY_INFO (f);
  93
  94   if (!display_info->has_palette)
  95     return;
  96
  97   if (display_info->palette == 0)
  98     return;
  99
 100   if (!NILP (Vw32_enable_palette))
 101     f->output_data.w32->old_palette =
 102       SelectPalette (hdc, display_info->palette, FALSE);
 103   else
 104     f->output_data.w32->old_palette = NULL;
 105
 106   if (RealizePalette (hdc) != GDI_ERROR)
 107   {
 108     Lisp_Object frame, framelist;
 109     FOR_EACH_FRAME (framelist, frame)
 110     {
 111       SET_FRAME_GARBAGED (XFRAME (frame));
 112     }
 113   }
 114 }
 115
 116 void
 117 deselect_palette (struct frame *f, HDC hdc)
 118 {
 119   if (f->output_data.w32->old_palette)
 120     SelectPalette (hdc, f->output_data.w32->old_palette, FALSE);
 121 }
 122
 123 /* Get a DC for frame and select palette for drawing; force an update of
 124    all frames if palette's mapping changes.  */
 125 HDC
 126 get_frame_dc (struct frame *f)
 127 {
 128   HDC hdc;
 129
 130   if (f->output_method != output_w32)
 131     emacs_abort ();
 132
 133   enter_crit ();
 134
 135   hdc = GetDC (f->output_data.w32->window_desc);
 136
 137   /* If this gets called during startup before the frame is valid,
 138      there is a chance of corrupting random data or crashing. */
 139   if (hdc)
 140     select_palette (f, hdc);
 141
 142   return hdc;
 143 }
 144
 145 int
 146 release_frame_dc (struct frame *f, HDC hdc)
 147 {
 148   int ret;
 149
 150   deselect_palette (f, hdc);
 151   ret = ReleaseDC (f->output_data.w32->window_desc, hdc);
 152
 153   leave_crit ();
 154
 155   return ret;
 156 }
 157
 158 typedef struct int_msg
 159 {
 160   W32Msg w32msg;
 161   struct int_msg *lpNext;
 162 } int_msg;
 163
 164 int_msg *lpHead = NULL;
 165 int_msg *lpTail = NULL;
 166 int nQueue = 0;
 167
 168 BOOL
 169 get_next_msg (W32Msg * lpmsg, BOOL bWait)
 170 {
 171   BOOL bRet = FALSE;
 172
 173   enter_crit ();
 174
 175   /* The while loop takes care of multiple sets */
 176
 177   while (!nQueue && bWait)
 178     {
 179       leave_crit ();
 180       WaitForSingleObject (input_available, INFINITE);
 181       enter_crit ();
 182     }
 183
 184   if (nQueue)
 185     {
 186       memcpy (lpmsg, &lpHead->w32msg, sizeof (W32Msg));
 187
 188       {
 189         int_msg * lpCur = lpHead;
 190
 191         lpHead = lpHead->lpNext;
 192
 193         myfree (lpCur);
 194       }
 195
 196       nQueue--;
 197       /* Consolidate WM_PAINT messages to optimize redrawing.  */
 198       if (lpmsg->msg.message == WM_PAINT && nQueue)
 199         {
 200           int_msg * lpCur = lpHead;
 201           int_msg * lpPrev = NULL;
 202           int_msg * lpNext = NULL;
 203
 204           while (lpCur && nQueue)
 205             {
 206               lpNext = lpCur->lpNext;
 207               if (lpCur->w32msg.msg.message == WM_PAINT)
 208                 {
 209                   /* Remove this message from the queue.  */
 210                   if (lpPrev)
 211                     lpPrev->lpNext = lpNext;
 212                   else
 213                     lpHead = lpNext;
 214
 215                   if (lpCur == lpTail)
 216                     lpTail = lpPrev;
 217
 218                   /* Adjust clip rectangle to cover both.  */
 219                   if (!UnionRect (&(lpmsg->rect), &(lpmsg->rect),
 220                                   &(lpCur->w32msg.rect)))
 221                     {
 222                       SetRectEmpty (&(lpmsg->rect));
 223                     }
 224
 225                   myfree (lpCur);
 226
 227                   nQueue--;
 228
 229                   lpCur = lpNext;
 230                 }
 231               else
 232                 {
 233                   lpPrev = lpCur;
 234                   lpCur = lpNext;
 235                 }
 236             }
 237         }
 238
 239       bRet = TRUE;
 240     }
 241
 242   if (nQueue == 0)
 243     ResetEvent (input_available);
 244
 245   leave_crit ();
 246
 247   return (bRet);
 248 }
 249
 250 extern char * w32_strerror (int error_no);
 251
 252 /* Tell the main thread that we have input available; if the main
 253    thread is blocked in select(), we wake it up here.  */
 254 static void
 255 notify_msg_ready (void)
 256 {
 257   SetEvent (input_available);
 258
 259 #ifdef CYGWIN
 260   /* Wakes up the main thread, which is blocked select()ing for /dev/windows,
 261      among other files.  */
 262   (void) PostThreadMessage (dwMainThreadId, WM_EMACS_INPUT_READY, 0, 0);
 263 #endif /* CYGWIN */
 264 }
 265
 266 BOOL
 267 post_msg (W32Msg * lpmsg)
 268 {
 269   int_msg * lpNew = (int_msg *) myalloc (sizeof (int_msg));
 270
 271   if (!lpNew)
 272     return (FALSE);
 273
 274   memcpy (&lpNew->w32msg, lpmsg, sizeof (W32Msg));
 275   lpNew->lpNext = NULL;
 276
 277   enter_crit ();
 278
 279   if (nQueue++)
 280     {
 281       lpTail->lpNext = lpNew;
 282     }
 283   else
 284     {
 285       lpHead = lpNew;
 286     }
 287
 288   lpTail = lpNew;
 289   notify_msg_ready ();
 290   leave_crit ();
 291
 292   return (TRUE);
 293 }
 294
 295 BOOL
 296 prepend_msg (W32Msg *lpmsg)
 297 {
 298   int_msg * lpNew = (int_msg *) myalloc (sizeof (int_msg));
 299
 300   if (!lpNew)
 301     return (FALSE);
 302
 303   memcpy (&lpNew->w32msg, lpmsg, sizeof (W32Msg));
 304
 305   enter_crit ();
 306
 307   nQueue++;
 308   lpNew->lpNext = lpHead;
 309   lpHead = lpNew;
 310   notify_msg_ready ();
 311   leave_crit ();
 312
 313   return (TRUE);
 314 }
 315
 316 /* Process all messages in the current thread's queue.  Value is 1 if
 317    one of these messages was WM_EMACS_FILENOTIFY, zero otherwise.  */
 318 int
 319 drain_message_queue (void)
 320 {
 321   MSG msg;
 322   int retval = 0;
 323
 324   while (PeekMessage (&msg, NULL, 0, 0, PM_REMOVE))
 325     {
 326       if (msg.message == WM_EMACS_FILENOTIFY)
 327         retval = 1;
 328       TranslateMessage (&msg);
 329       DispatchMessage (&msg);
 330     }
 331   return retval;
 332 }