layout/style/nsLayoutStylesheetCache.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is Mozilla Gecko Layout
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Benjamin Smedberg <bsmedberg@covad.net>
  19  * Portions created by the Initial Developer are Copyright (C) 2004
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either the GNU General Public License Version 2 or later (the "GPL"), or
  26  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
  28  * of those above. If you wish to allow use of your version of this file only
  29  * under the terms of either the GPL or the LGPL, and not to allow others to
  30  * use your version of this file under the terms of the MPL, indicate your
  31  * decision by deleting the provisions above and replace them with the notice
  32  * and other provisions required by the GPL or the LGPL. If you do not delete
  33  * the provisions above, a recipient may use your version of this file under
  34  * the terms of any one of the MPL, the GPL or the LGPL.
  35  *
  36  * ***** END LICENSE BLOCK ***** */
  37
  38 #include "nsLayoutStylesheetCache.h"
  39
  40 #include "nsAppDirectoryServiceDefs.h"
  41 #include "nsICSSLoader.h"
  42 #include "nsIFile.h"
  43 #include "nsLayoutCID.h"
  44 #include "nsNetUtil.h"
  45 #include "nsIObserverService.h"
  46 #include "nsServiceManagerUtils.h"
  47
  48 NS_IMPL_ISUPPORTS1(nsLayoutStylesheetCache, nsIObserver)
  49
  50 nsresult
  51 nsLayoutStylesheetCache::Observe(nsISupports* aSubject,
  52                             const char* aTopic,
  53                             const PRUnichar* aData)
  54 {
  55   if (!strcmp(aTopic, "profile-before-change")) {
  56     mUserContentSheet = nsnull;
  57     mUserChromeSheet  = nsnull;
  58   }
  59   else if (!strcmp(aTopic, "profile-do-change")) {
  60     InitFromProfile();
  61   }
  62   else if (strcmp(aTopic, "chrome-flush-skin-caches") == 0 ||
  63            strcmp(aTopic, "chrome-flush-caches") == 0) {
  64     mScrollbarsSheet = nsnull;
  65     mFormsSheet = nsnull;
  66   }
  67   else {
  68     NS_NOTREACHED("Unexpected observer topic.");
  69   }
  70   return NS_OK;
  71 }
  72
  73 nsICSSStyleSheet*
  74 nsLayoutStylesheetCache::ScrollbarsSheet()
  75 {
  76   EnsureGlobal();
  77   if (!gStyleCache)
  78     return nsnull;
  79
  80   if (!gStyleCache->mScrollbarsSheet) {
  81     nsCOMPtr<nsIURI> sheetURI;
  82     NS_NewURI(getter_AddRefs(sheetURI),
  83               NS_LITERAL_CSTRING("chrome://global/skin/scrollbars.css"));
  84
  85     // Scrollbars don't need access to unsafe rules
  86     if (sheetURI)
  87       LoadSheet(sheetURI, gStyleCache->mScrollbarsSheet, PR_FALSE);
  88     NS_ASSERTION(gStyleCache->mScrollbarsSheet, "Could not load scrollbars.css.");
  89   }
  90
  91   return gStyleCache->mScrollbarsSheet;
  92 }
  93
  94 nsICSSStyleSheet*
  95 nsLayoutStylesheetCache::FormsSheet()
  96 {
  97   EnsureGlobal();
  98   if (!gStyleCache)
  99     return nsnull;
 100
 101   if (!gStyleCache->mFormsSheet) {
 102     nsCOMPtr<nsIURI> sheetURI;
 103       NS_NewURI(getter_AddRefs(sheetURI),
 104                 NS_LITERAL_CSTRING("resource://gre/res/forms.css"));
 105
 106     // forms.css needs access to unsafe rules
 107     if (sheetURI)
 108       LoadSheet(sheetURI, gStyleCache->mFormsSheet, PR_TRUE);
 109
 110     NS_ASSERTION(gStyleCache->mFormsSheet, "Could not load forms.css.");
 111   }
 112
 113   return gStyleCache->mFormsSheet;
 114 }
 115
 116 nsICSSStyleSheet*
 117 nsLayoutStylesheetCache::UserContentSheet()
 118 {
 119   EnsureGlobal();
 120   if (!gStyleCache)
 121     return nsnull;
 122
 123   return gStyleCache->mUserContentSheet;
 124 }
 125
 126 nsICSSStyleSheet*
 127 nsLayoutStylesheetCache::UserChromeSheet()
 128 {
 129   EnsureGlobal();
 130   if (!gStyleCache)
 131     return nsnull;
 132
 133   return gStyleCache->mUserChromeSheet;
 134 }
 135
 136 void
 137 nsLayoutStylesheetCache::Shutdown()
 138 {
 139   NS_IF_RELEASE(gCSSLoader);
 140   NS_IF_RELEASE(gStyleCache);
 141 }
 142
 143 nsLayoutStylesheetCache::nsLayoutStylesheetCache()
 144 {
 145   nsCOMPtr<nsIObserverService> obsSvc =
 146     do_GetService("@mozilla.org/observer-service;1");
 147   NS_ASSERTION(obsSvc, "No global observer service?");
 148
 149   if (obsSvc) {
 150     obsSvc->AddObserver(this, "profile-before-change", PR_FALSE);
 151     obsSvc->AddObserver(this, "profile-do-change", PR_FALSE);
 152     obsSvc->AddObserver(this, "chrome-flush-skin-caches", PR_FALSE);
 153     obsSvc->AddObserver(this, "chrome-flush-caches", PR_FALSE);
 154   }
 155
 156   InitFromProfile();
 157 }
 158
 159 nsLayoutStylesheetCache::~nsLayoutStylesheetCache()
 160 {
 161   gCSSLoader = nsnull;
 162   gStyleCache = nsnull;
 163 }
 164
 165 void
 166 nsLayoutStylesheetCache::EnsureGlobal()
 167 {
 168   if (gStyleCache) return;
 169
 170   gStyleCache = new nsLayoutStylesheetCache();
 171   if (!gStyleCache) return;
 172
 173   NS_ADDREF(gStyleCache);
 174 }
 175
 176 void
 177 nsLayoutStylesheetCache::InitFromProfile()
 178 {
 179   nsCOMPtr<nsIFile> contentFile;
 180   nsCOMPtr<nsIFile> chromeFile;
 181
 182   NS_GetSpecialDirectory(NS_APP_USER_CHROME_DIR,
 183                          getter_AddRefs(contentFile));
 184   if (!contentFile) {
 185     // if we don't have a profile yet, that's OK!
 186     return;
 187   }
 188
 189   contentFile->Clone(getter_AddRefs(chromeFile));
 190   if (!chromeFile) return;
 191
 192   contentFile->Append(NS_LITERAL_STRING("userContent.css"));
 193   chromeFile->Append(NS_LITERAL_STRING("userChrome.css"));
 194
 195   LoadSheetFile(contentFile, mUserContentSheet);
 196   LoadSheetFile(chromeFile, mUserChromeSheet);
 197 }
 198
 199 void
 200 nsLayoutStylesheetCache::LoadSheetFile(nsIFile* aFile, nsCOMPtr<nsICSSStyleSheet> &aSheet)
 201 {
 202   PRBool exists = PR_FALSE;
 203   aFile->Exists(&exists);
 204
 205   if (!exists) return;
 206
 207   nsCOMPtr<nsIURI> uri;
 208   NS_NewFileURI(getter_AddRefs(uri), aFile);
 209
 210   LoadSheet(uri, aSheet, PR_FALSE);
 211 }
 212
 213 void
 214 nsLayoutStylesheetCache::LoadSheet(nsIURI* aURI, nsCOMPtr<nsICSSStyleSheet> &aSheet,
 215                                    PRBool aEnableUnsafeRules)
 216 {
 217   if (!aURI) {
 218     NS_ERROR("Null URI. Out of memory?");
 219     return;
 220   }
 221
 222   if (!gCSSLoader)
 223     NS_NewCSSLoader(&gCSSLoader);
 224
 225   if (gCSSLoader) {
 226     gCSSLoader->LoadSheetSync(aURI, aEnableUnsafeRules, getter_AddRefs(aSheet));
 227   }
 228 }
 229
 230 nsLayoutStylesheetCache*
 231 nsLayoutStylesheetCache::gStyleCache = nsnull;
 232
 233 nsICSSLoader*
 234 nsLayoutStylesheetCache::gCSSLoader = nsnull;