1 /* 2 * Copyright (c) 2010 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef CrossProcessFontLoading_h 32 #define CrossProcessFontLoading_h 33 34 #import <wtf/RefCounted.h> 35 #import <wtf/RetainPtr.h> 36 37 typedef struct CGFont* CGFontRef; 38 typedef UInt32 ATSFontContainerRef; 39 typedef UInt32 ATSFontRef; 40 41 namespace WebCore { 42 43 // MemoryActivatedFont encapsulates a font loaded from another process and 44 // activated from memory. 45 // 46 // Responsibilities: 47 // * Holder for the CGFontRef & ATSFontRef belonging to the activated font. 48 // * Responsible for unloading the font container when done. 49 // 50 // Memory Management: 51 // The class is reference counted, with each instance of FontPlatformData that 52 // uses this class holding a reference to it. 53 // Entries are kept track of internally in a hash to allow quick lookup 54 // of existing instances for reuse: 55 // - fontCacheBySrcFontContainerRef() - key is the ATSFontContainerRef 56 // corresponding to the *original in-process NSFont* whose loading was blocked 57 // by the sandbox. 58 // This is needed to allow lookup of a pre-existing MemoryActivatedFont when 59 // creating a new FontPlatformData object. 60 // 61 // Assumptions: 62 // This code assumes that an ATSFontRef is a unique identifier tied to an 63 // activated font. i.e. After we activate a font, its ATSFontRef doesn't 64 // change. 65 // It also assumes that the ATSFoncontainerRef for two in-memory NSFonts that 66 // correspond to the same on-disk font file are always the same and don't change 67 // with time. 68 // 69 // Flushing caches: 70 // When the system notifies us of a system font cache flush, all FontDataCache 71 // objects are destroyed. This should in turn dereference all 72 // MemoryActivatedFonts and thus unload all in-memory fonts. 73 class MemoryActivatedFont : public RefCounted<MemoryActivatedFont> { 74 public: 75 // Use to create a new object, see docs on constructor below. 76 static PassRefPtr<MemoryActivatedFont> create(ATSFontContainerRef srcFontContainerRef, ATSFontContainerRef container); 77 ~MemoryActivatedFont(); 78 79 // Get cached CGFontRef corresponding to the in-memory font. cgFont()80 CGFontRef cgFont() { return m_cgFont.get(); } 81 82 // Get cached ATSFontRef corresponding to the in-memory font. atsFontRef()83 ATSFontRef atsFontRef() { return m_atsFontRef; } 84 85 private: 86 // srcFontRef - ATSFontRef belonging to the NSFont object that failed to 87 // load in-process. 88 // container - a font container corresponding to an identical font that 89 // we loaded cross-process. 90 MemoryActivatedFont(ATSFontContainerRef srcFontContainerRef, ATSFontContainerRef container); 91 92 ATSFontContainerRef m_fontContainer; 93 WTF::RetainPtr<CGFontRef> m_cgFont; 94 ATSFontRef m_atsFontRef; 95 ATSFontContainerRef m_srcFontContainerRef; 96 }; 97 98 } // namespace WebCore 99 100 #endif // CrossProcessFontLoading_h 101