Dogcows Code - chaz/openbox/blob - src/GCCache.cc

   1 // -*- mode: C++; indent-tabs-mode: nil; c-basic-offset: 2; -*-
   2 // GCCache.cc for Blackbox - an X11 Window manager
   3 // Copyright (c) 2001 - 2002 Sean 'Shaleh' Perry <shaleh at debian.org>
   4 // Copyright (c) 1997 - 2000, 2002 Bradley T Hughes <bhughes at trolltech.com>
   5 //
   6 // Permission is hereby granted, free of charge, to any person obtaining a
   7 // copy of this software and associated documentation files (the "Software"),
   8 // to deal in the Software without restriction, including without limitation
   9 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10 // and/or sell copies of the Software, and to permit persons to whom the
  11 // Software is furnished to do so, subject to the following conditions:
  12 //
  13 // The above copyright notice and this permission notice shall be included in
  14 // all copies or substantial portions of the Software.
  15 //
  16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19 // THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22 // DEALINGS IN THE SOFTWARE.
  23
  24 #ifdef HAVE_CONFIG_H
  25 #  include "../config.h"
  26 #endif // HAVE_CONFIG_H
  27
  28 extern "C" {
  29 #include <stdio.h>
  30 }
  31
  32 #include "GCCache.hh"
  33 #include "BaseDisplay.hh"
  34 #include "Color.hh"
  35 #include "Util.hh"
  36
  37
  38 void BGCCacheContext::set(const BColor &_color,
  39                           const XFontStruct * const _font,
  40                           const int _function, const int _subwindow) {
  41   XGCValues gcv;
  42   pixel = gcv.foreground = _color.pixel();
  43   function = gcv.function = _function;
  44   subwindow = gcv.subwindow_mode = _subwindow;
  45   unsigned long mask = GCForeground | GCFunction | GCSubwindowMode;
  46
  47   if (_font) {
  48     fontid = gcv.font = _font->fid;
  49     mask |= GCFont;
  50   } else {
  51     fontid = 0;
  52   }
  53
  54   XChangeGC(display->getXDisplay(), gc, mask, &gcv);
  55 }
  56
  57
  58 void BGCCacheContext::set(const XFontStruct * const _font) {
  59   if (! _font) {
  60     fontid = 0;
  61     return;
  62   }
  63
  64   XGCValues gcv;
  65   fontid = gcv.font = _font->fid;
  66   XChangeGC(display->getXDisplay(), gc, GCFont, &gcv);
  67 }
  68
  69
  70 BGCCache::BGCCache(const BaseDisplay * const _display)
  71   : display(_display),  context_count(128u),
  72     cache_size(16u), cache_buckets(8u),
  73     cache_total_size(cache_size * cache_buckets) {
  74
  75   contexts = new BGCCacheContext*[context_count];
  76   unsigned int i;
  77   for (i = 0; i < context_count; i++) {
  78     contexts[i] = new BGCCacheContext(display);
  79   }
  80
  81   cache = new BGCCacheItem*[cache_total_size];
  82   for (i = 0; i < cache_total_size; ++i) {
  83     cache[i] = new BGCCacheItem;
  84   }
  85 }
  86
  87
  88 BGCCache::~BGCCache(void) {
  89   std::for_each(contexts, contexts + context_count, PointerAssassin());
  90   std::for_each(cache, cache + cache_total_size, PointerAssassin());
  91   delete [] cache;
  92   delete [] contexts;
  93 }
  94
  95
  96 BGCCacheContext *BGCCache::nextContext(unsigned int scr) {
  97   Window hd = display->getScreenInfo(scr)->getRootWindow();
  98
  99   BGCCacheContext *c;
 100
 101   for (unsigned int i = 0; i < context_count; ++i) {
 102     c = contexts[i];
 103
 104     if (! c->gc) {
 105       c->gc = XCreateGC(display->getXDisplay(), hd, 0, 0);
 106       c->used = false;
 107       c->screen = scr;
 108     }
 109     if (! c->used && c->screen == scr) {
 110       c->used = true;
 111       return c;
 112     }
 113   }
 114
 115   fprintf(stderr, "BGCCache: context fault!\n");
 116   abort();
 117   return (BGCCacheContext*) 0; // not reached
 118 }
 119
 120
 121 void BGCCache::release(BGCCacheContext *ctx) {
 122   ctx->used = false;
 123 }
 124
 125
 126 BGCCacheItem *BGCCache::find(const BColor &_color,
 127                              const XFontStruct * const _font,
 128                              int _function, int _subwindow) {
 129   const unsigned long pixel = _color.pixel();
 130   const unsigned int screen = _color.screen();
 131   const int key = _color.red() ^ _color.green() ^ _color.blue();
 132   int k = (key % cache_size) * cache_buckets;
 133   int i = 0; // loop variable
 134   BGCCacheItem *c = cache[ k ], *prev = 0;
 135
 136   // this will either loop 8 times then return/abort or it will stop matching
 137   while (c->ctx &&
 138          (c->ctx->pixel != pixel || c->ctx->function != _function ||
 139           c->ctx->subwindow != _subwindow || c->ctx->screen != screen)) {
 140     if (i < 7) {
 141       prev = c;
 142       c = cache[ ++k ];
 143       ++i;
 144       continue;
 145     }
 146     if (c->count == 0 && c->ctx->screen == screen) {
 147       // use this cache item
 148       c->ctx->set(_color, _font, _function, _subwindow);
 149       c->ctx->used = true;
 150       c->count = 1;
 151       c->hits = 1;
 152       return c;
 153     }
 154     // cache fault!
 155     fprintf(stderr, "BGCCache: cache fault\n");
 156     abort();
 157   }
 158
 159   const unsigned long fontid = _font ? _font->fid : 0;
 160   if (c->ctx) {
 161     // reuse existing context
 162     if (fontid && fontid != c->ctx->fontid)
 163       c->ctx->set(_font);
 164     c->count++;
 165     c->hits++;
 166     if (prev && c->hits > prev->hits) {
 167       cache[ k     ] = prev;
 168       cache[ k - 1 ] = c;
 169     }
 170   } else {
 171     c->ctx = nextContext(screen);
 172     c->ctx->set(_color, _font, _function, _subwindow);
 173     c->ctx->used = true;
 174     c->count = 1;
 175     c->hits = 1;
 176   }
 177
 178   return c;
 179 }
 180
 181
 182 void BGCCache::release(BGCCacheItem *_item) {
 183   _item->count--;
 184 }
 185
 186
 187 void BGCCache::purge(void) {
 188   for (unsigned int i = 0; i < cache_total_size; ++i) {
 189     BGCCacheItem *d = cache[ i ];
 190
 191     if (d->ctx && d->count == 0) {
 192       release(d->ctx);
 193       d->ctx = 0;
 194     }
 195   }
 196 }