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 MemoryActivatedFont_h 32 #define MemoryActivatedFont_h 33 34 #import <wtf/RefCounted.h> 35 #import <wtf/RetainPtr.h> 36 #import <wtf/text/WTFString.h> 37 38 typedef struct CGFont* CGFontRef; 39 40 namespace WebCore { 41 42 // MemoryActivatedFont encapsulates a font loaded from another process and 43 // activated from memory. 44 // 45 // Responsibilities: 46 // * Holder for the CGFontRef & ATSFontRef belonging to the activated font. 47 // * Responsible for unloading the font container when done. 48 // 49 // Memory Management: 50 // The class is reference counted, with each instance of FontPlatformData that 51 // uses this class holding a reference to it. 52 // Entries are kept track of internally in a hash to allow quick lookup 53 // of existing instances for reuse: 54 // - fontCacheBySrcFontContainerRef() - key is the ATSFontContainerRef 55 // corresponding to the *original in-process NSFont* whose loading was blocked 56 // by the sandbox. 57 // This is needed to allow lookup of a pre-existing MemoryActivatedFont when 58 // creating a new FontPlatformData object. 59 // 60 // Assumptions: 61 // This code assumes that an ATSFontRef is a unique identifier tied to an 62 // activated font. i.e. After we activate a font, its ATSFontRef doesn't 63 // change. 64 // It also assumes that the ATSFoncontainerRef for two in-memory NSFonts that 65 // correspond to the same on-disk font file are always the same and don't change 66 // with time. 67 // 68 // Flushing caches: 69 // When the system notifies us of a system font cache flush, all FontDataCache 70 // objects are destroyed. This should in turn dereference all 71 // MemoryActivatedFonts and thus unload all in-memory fonts. 72 class MemoryActivatedFont : public RefCounted<MemoryActivatedFont> { 73 public: 74 // Use to create a new object, see docs on constructor below. 75 static PassRefPtr<MemoryActivatedFont> create(uint32_t fontID, NSFont*, CGFontRef); 76 ~MemoryActivatedFont(); 77 78 // Get cached CGFontRef corresponding to the in-memory font. 79 CGFontRef cgFont() { return m_cgFont.get(); } 80 81 private: 82 // srcFontRef - ATSFontRef belonging to the NSFont object that failed to 83 // load in-process. 84 // container - a font container corresponding to an identical font that 85 // we loaded cross-process. 86 MemoryActivatedFont(uint32_t fontID, NSFont*, CGFontRef); 87 88 WTF::RetainPtr<CGFontRef> m_cgFont; 89 uint32_t m_fontID; 90 WTF::String m_inSandboxHashKey; 91 }; 92 93 } // namespace WebCore 94 95 #endif // MemoryActivatedFont_h 96