1 /*
   2  * Copyright (c) 2008, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.font;
  27 
  28 import java.awt.Font;
  29 import java.io.BufferedReader;
  30 import java.io.File;
  31 import java.io.FileInputStream;
  32 import java.io.InputStreamReader;
  33 import java.lang.ref.SoftReference;
  34 import java.util.concurrent.ConcurrentHashMap;
  35 import java.security.AccessController;
  36 
  37 import java.security.PrivilegedAction;
  38 import javax.swing.plaf.FontUIResource;
  39 
  40 import sun.util.logging.PlatformLogger;
  41 
  42 /**
  43  * A collection of utility methods.
  44  */
  45 public final class FontUtilities {
  46 
  47     public static boolean isSolaris;
  48 
  49     public static boolean isLinux;
  50 
  51     public static boolean isMacOSX;
  52 
  53     public static boolean isAIX;
  54 
  55     public static boolean useJDKScaler;
  56 
  57     public static boolean isWindows;
  58 
  59     private static boolean debugFonts = false;
  60     private static PlatformLogger logger = null;
  61     private static boolean logging;
  62 
  63     // This static initializer block figures out the OS constants.
  64     static {
  65 
  66         AccessController.doPrivileged(new PrivilegedAction<Object>() {
  67             @SuppressWarnings("deprecation") // PlatformLogger.setLevel is deprecated.
  68             @Override
  69             public Object run() {
  70                 String osName = System.getProperty("os.name", "unknownOS");
  71                 isSolaris = osName.startsWith("SunOS");
  72 
  73                 isLinux = osName.startsWith("Linux");
  74 
  75                 isMacOSX = osName.contains("OS X"); // TODO: MacOSX
  76 
  77                 isAIX = osName.startsWith("AIX");
  78 
  79                 /* If set to "jdk", use the JDK's scaler rather than
  80                  * the platform one. This may be a no-op on platforms where
  81                  * JDK has been configured so that it always relies on the
  82                  * platform scaler. The principal case where it has an
  83                  * effect is that on Windows, 2D will never use GDI.
  84                  */
  85                 String scalerStr = System.getProperty("sun.java2d.font.scaler");
  86                 if (scalerStr != null) {
  87                     useJDKScaler = "jdk".equals(scalerStr);
  88                 } else {
  89                     useJDKScaler = false;
  90                 }
  91                 isWindows = osName.startsWith("Windows");
  92                 String debugLevel =
  93                     System.getProperty("sun.java2d.debugfonts");
  94 
  95                 if (debugLevel != null && !debugLevel.equals("false")) {
  96                     debugFonts = true;
  97                     logger = PlatformLogger.getLogger("sun.java2d");
  98                     if (debugLevel.equals("warning")) {
  99                         logger.setLevel(PlatformLogger.Level.WARNING);
 100                     } else if (debugLevel.equals("severe")) {
 101                         logger.setLevel(PlatformLogger.Level.SEVERE);
 102                     }
 103                 }
 104 
 105                 if (debugFonts) {
 106                     logger = PlatformLogger.getLogger("sun.java2d");
 107                     logging = logger.isEnabled();
 108                 }
 109 
 110                 return null;
 111             }
 112         });
 113     }
 114 
 115     /**
 116      * Referenced by code in the JDK which wants to test for the
 117      * minimum char code for which layout may be required.
 118      * Note that even basic latin text can benefit from ligatures,
 119      * eg "ffi" but we presently apply those only if explicitly
 120      * requested with TextAttribute.LIGATURES_ON.
 121      * The value here indicates the lowest char code for which failing
 122      * to invoke layout would prevent acceptable rendering.
 123      */
 124     public static final int MIN_LAYOUT_CHARCODE = 0x0300;
 125 
 126     /**
 127      * Referenced by code in the JDK which wants to test for the
 128      * maximum char code for which layout may be required.
 129      * Note this does not account for supplementary characters
 130      * where the caller interprets 'layout' to mean any case where
 131      * one 'char' (ie the java type char) does not map to one glyph
 132      */
 133     public static final int MAX_LAYOUT_CHARCODE = 0x206F;
 134 
 135     /**
 136      * Calls the private getFont2D() method in java.awt.Font objects.
 137      *
 138      * @param font the font object to call
 139      *
 140      * @return the Font2D object returned by Font.getFont2D()
 141      */
 142     public static Font2D getFont2D(Font font) {
 143         return FontAccess.getFontAccess().getFont2D(font);
 144     }
 145 
 146     /**
 147      * Return true if there any characters which would trigger layout.
 148      * This method considers supplementary characters to be simple,
 149      * since we do not presently invoke layout on any code points in
 150      * outside the BMP.
 151      */
 152     public static boolean isComplexScript(char [] chs, int start, int limit) {
 153 
 154         for (int i = start; i < limit; i++) {
 155             if (chs[i] < MIN_LAYOUT_CHARCODE) {
 156                 continue;
 157             }
 158             else if (isComplexCharCode(chs[i])) {
 159                 return true;
 160             }
 161         }
 162         return false;
 163     }
 164 
 165     /**
 166      * If there is anything in the text which triggers a case
 167      * where char->glyph does not map 1:1 in straightforward
 168      * left->right ordering, then this method returns true.
 169      * Scripts which might require it but are not treated as such
 170      * due to JDK implementations will not return true.
 171      * ie a 'true' return is an indication of the treatment by
 172      * the implementation.
 173      * Whether supplementary characters should be considered is dependent
 174      * on the needs of the caller. Since this method accepts the 'char' type
 175      * then such chars are always represented by a pair. From a rendering
 176      * perspective these will all (in the cases I know of) still be one
 177      * unicode character -> one glyph. But if a caller is using this to
 178      * discover any case where it cannot make naive assumptions about
 179      * the number of chars, and how to index through them, then it may
 180      * need the option to have a 'true' return in such a case.
 181      */
 182     public static boolean isComplexText(char [] chs, int start, int limit) {
 183 
 184         for (int i = start; i < limit; i++) {
 185             if (chs[i] < MIN_LAYOUT_CHARCODE) {
 186                 continue;
 187             }
 188             else if (isNonSimpleChar(chs[i])) {
 189                 return true;
 190             }
 191         }
 192         return false;
 193     }
 194 
 195     /* This is almost the same as the method above, except it takes a
 196      * char which means it may include undecoded surrogate pairs.
 197      * The distinction is made so that code which needs to identify all
 198      * cases in which we do not have a simple mapping from
 199      * char->unicode character->glyph can be identified.
 200      * For example measurement cannot simply sum advances of 'chars',
 201      * the caret in editable text cannot advance one 'char' at a time, etc.
 202      * These callers really are asking for more than whether 'layout'
 203      * needs to be run, they need to know if they can assume 1->1
 204      * char->glyph mapping.
 205      */
 206     public static boolean isNonSimpleChar(char ch) {
 207         return
 208             isComplexCharCode(ch) ||
 209             (ch >= CharToGlyphMapper.HI_SURROGATE_START &&
 210              ch <= CharToGlyphMapper.LO_SURROGATE_END);
 211     }
 212 
 213     /* If the character code falls into any of a number of unicode ranges
 214      * where we know that simple left->right layout mapping chars to glyphs
 215      * 1:1 and accumulating advances is going to produce incorrect results,
 216      * we want to know this so the caller can use a more intelligent layout
 217      * approach. A caller who cares about optimum performance may want to
 218      * check the first case and skip the method call if its in that range.
 219      * Although there's a lot of tests in here, knowing you can skip
 220      * CTL saves a great deal more. The rest of the checks are ordered
 221      * so that rather than checking explicitly if (>= start & <= end)
 222      * which would mean all ranges would need to be checked so be sure
 223      * CTL is not needed, the method returns as soon as it recognises
 224      * the code point is outside of a CTL ranges.
 225      * NOTE: Since this method accepts an 'int' it is asssumed to properly
 226      * represent a CHARACTER. ie it assumes the caller has already
 227      * converted surrogate pairs into supplementary characters, and so
 228      * can handle this case and doesn't need to be told such a case is
 229      * 'complex'.
 230      */
 231     public static boolean isComplexCharCode(int code) {
 232 
 233         if (code < MIN_LAYOUT_CHARCODE || code > MAX_LAYOUT_CHARCODE) {
 234             return false;
 235         }
 236         else if (code <= 0x036f) {
 237             // Trigger layout for combining diacriticals 0x0300->0x036f
 238             return true;
 239         }
 240         else if (code < 0x0590) {
 241             // No automatic layout for Greek, Cyrillic, Armenian.
 242              return false;
 243         }
 244         else if (code <= 0x06ff) {
 245             // Hebrew 0590 - 05ff
 246             // Arabic 0600 - 06ff
 247             return true;
 248         }
 249         else if (code < 0x0900) {
 250             return false; // Syriac and Thaana
 251         }
 252         else if (code <= 0x0e7f) {
 253             // if Indic, assume shaping for conjuncts, reordering:
 254             // 0900 - 097F Devanagari
 255             // 0980 - 09FF Bengali
 256             // 0A00 - 0A7F Gurmukhi
 257             // 0A80 - 0AFF Gujarati
 258             // 0B00 - 0B7F Oriya
 259             // 0B80 - 0BFF Tamil
 260             // 0C00 - 0C7F Telugu
 261             // 0C80 - 0CFF Kannada
 262             // 0D00 - 0D7F Malayalam
 263             // 0D80 - 0DFF Sinhala
 264             // 0E00 - 0E7F if Thai, assume shaping for vowel, tone marks
 265             return true;
 266         }
 267         else if (code <  0x0f00) {
 268             return false;
 269         }
 270         else if (code <= 0x0fff) { // U+0F00 - U+0FFF Tibetan
 271             return true;
 272         }
 273         else if (code < 0x1100) {
 274             return false;
 275         }
 276         else if (code < 0x11ff) { // U+1100 - U+11FF Old Hangul
 277             return true;
 278         }
 279         else if (code < 0x1780) {
 280             return false;
 281         }
 282         else if (code <= 0x17ff) { // 1780 - 17FF Khmer
 283             return true;
 284         }
 285         else if (code < 0x200c) {
 286             return false;
 287         }
 288         else if (code <= 0x200d) { //  zwj or zwnj
 289             return true;
 290         }
 291         else if (code >= 0x202a && code <= 0x202e) { // directional control
 292             return true;
 293         }
 294         else if (code >= 0x206a && code <= 0x206f) { // directional control
 295             return true;
 296         }
 297         return false;
 298     }
 299 
 300     public static PlatformLogger getLogger() {
 301         return logger;
 302     }
 303 
 304     public static boolean isLogging() {
 305         return logging;
 306     }
 307 
 308     public static boolean debugFonts() {
 309         return debugFonts;
 310     }
 311 
 312 
 313     // The following methods are used by Swing.
 314 
 315     /* Revise the implementation to in fact mean "font is a composite font.
 316      * This ensures that Swing components will always benefit from the
 317      * fall back fonts
 318      */
 319     public static boolean fontSupportsDefaultEncoding(Font font) {
 320         return getFont2D(font) instanceof CompositeFont;
 321     }
 322 
 323     /**
 324      * This method is provided for internal and exclusive use by Swing.
 325      *
 326      * It may be used in conjunction with fontSupportsDefaultEncoding(Font)
 327      * In the event that a desktop properties font doesn't directly
 328      * support the default encoding, (ie because the host OS supports
 329      * adding support for the current locale automatically for native apps),
 330      * then Swing calls this method to get a font which  uses the specified
 331      * font for the code points it covers, but also supports this locale
 332      * just as the standard composite fonts do.
 333      * Note: this will over-ride any setting where an application
 334      * specifies it prefers locale specific composite fonts.
 335      * The logic for this, is that this method is used only where the user or
 336      * application has specified that the native L&F be used, and that
 337      * we should honour that request to use the same font as native apps use.
 338      *
 339      * The behaviour of this method is to construct a new composite
 340      * Font object that uses the specified physical font as its first
 341      * component, and adds all the components of "dialog" as fall back
 342      * components.
 343      * The method currently assumes that only the size and style attributes
 344      * are set on the specified font. It doesn't copy the font transform or
 345      * other attributes because they aren't set on a font created from
 346      * the desktop. This will need to be fixed if use is broadened.
 347      *
 348      * Operations such as Font.deriveFont will work properly on the
 349      * font returned by this method for deriving a different point size.
 350      * Additionally it tries to support a different style by calling
 351      * getNewComposite() below. That also supports replacing slot zero
 352      * with a different physical font but that is expected to be "rare".
 353      * Deriving with a different style is needed because its been shown
 354      * that some applications try to do this for Swing FontUIResources.
 355      * Also operations such as new Font(font.getFontName(..), Font.PLAIN, 14);
 356      * will NOT yield the same result, as the new underlying CompositeFont
 357      * cannot be "looked up" in the font registry.
 358      * This returns a FontUIResource as that is the Font sub-class needed
 359      * by Swing.
 360      * Suggested usage is something like :
 361      * FontUIResource fuir;
 362      * Font desktopFont = getDesktopFont(..);
 363      * if (FontManager.fontSupportsDefaultEncoding(desktopFont)) {
 364      *   fuir = new FontUIResource(desktopFont);
 365      * } else {
 366      *   fuir = FontManager.getCompositeFontUIResource(desktopFont);
 367      * }
 368      * return fuir;
 369      */
 370     private static volatile
 371         SoftReference<ConcurrentHashMap<PhysicalFont, CompositeFont>>
 372         compMapRef = new SoftReference<>(null);
 373 
 374     public static FontUIResource getCompositeFontUIResource(Font font) {
 375 
 376         FontUIResource fuir = new FontUIResource(font);
 377         Font2D font2D = FontUtilities.getFont2D(font);
 378 
 379         if (!(font2D instanceof PhysicalFont)) {
 380             /* Swing should only be calling this when a font is obtained
 381              * from desktop properties, so should generally be a physical font,
 382              * an exception might be for names like "MS Serif" which are
 383              * automatically mapped to "Serif", so there's no need to do
 384              * anything special in that case. But note that suggested usage
 385              * is first to call fontSupportsDefaultEncoding(Font) and this
 386              * method should not be called if that were to return true.
 387              */
 388              return fuir;
 389         }
 390 
 391         FontManager fm = FontManagerFactory.getInstance();
 392         Font2D dialog = fm.findFont2D("dialog", font.getStyle(), FontManager.NO_FALLBACK);
 393         // Should never be null, but MACOSX fonts are not CompositeFonts
 394         if (dialog == null || !(dialog instanceof CompositeFont)) {
 395             return fuir;
 396         }
 397         CompositeFont dialog2D = (CompositeFont)dialog;
 398         PhysicalFont physicalFont = (PhysicalFont)font2D;
 399         ConcurrentHashMap<PhysicalFont, CompositeFont> compMap = compMapRef.get();
 400         if (compMap == null) { // Its been collected.
 401             compMap = new ConcurrentHashMap<PhysicalFont, CompositeFont>();
 402             compMapRef = new SoftReference<>(compMap);
 403         }
 404         CompositeFont compFont = compMap.get(physicalFont);
 405         if (compFont == null) {
 406             compFont = new CompositeFont(physicalFont, dialog2D);
 407             compMap.put(physicalFont, compFont);
 408         }
 409         FontAccess.getFontAccess().setFont2D(fuir, compFont.handle);
 410         /* marking this as a created font is needed as only created fonts
 411          * copy their creator's handles.
 412          */
 413         FontAccess.getFontAccess().setCreatedFont(fuir);
 414         return fuir;
 415     }
 416 
 417    /* A small "map" from GTK/fontconfig names to the equivalent JDK
 418     * logical font name.
 419     */
 420     private static final String[][] nameMap = {
 421         {"sans",       "sansserif"},
 422         {"sans-serif", "sansserif"},
 423         {"serif",      "serif"},
 424         {"monospace",  "monospaced"}
 425     };
 426 
 427     public static String mapFcName(String name) {
 428         for (int i = 0; i < nameMap.length; i++) {
 429             if (name.equals(nameMap[i][0])) {
 430                 return nameMap[i][1];
 431             }
 432         }
 433         return null;
 434     }
 435 
 436 
 437     /* This is called by Swing passing in a fontconfig family name
 438      * such as "sans". In return Swing gets a FontUIResource instance
 439      * that has queried fontconfig to resolve the font(s) used for this.
 440      * Fontconfig will if asked return a list of fonts to give the largest
 441      * possible code point coverage.
 442      * For now we use only the first font returned by fontconfig, and
 443      * back it up with the most closely matching JDK logical font.
 444      * Essentially this means pre-pending what we return now with fontconfig's
 445      * preferred physical font. This could lead to some duplication in cases,
 446      * if we already included that font later. We probably should remove such
 447      * duplicates, but it is not a significant problem. It can be addressed
 448      * later as part of creating a Composite which uses more of the
 449      * same fonts as fontconfig. At that time we also should pay more
 450      * attention to the special rendering instructions fontconfig returns,
 451      * such as whether we should prefer embedded bitmaps over antialiasing.
 452      * There's no way to express that via a Font at present.
 453      */
 454     public static FontUIResource getFontConfigFUIR(String fcFamily,
 455                                                    int style, int size) {
 456 
 457         String mapped = mapFcName(fcFamily);
 458         if (mapped == null) {
 459             mapped = "sansserif";
 460         }
 461 
 462         FontUIResource fuir;
 463         FontManager fm = FontManagerFactory.getInstance();
 464         if (fm instanceof SunFontManager) {
 465             SunFontManager sfm = (SunFontManager) fm;
 466             fuir = sfm.getFontConfigFUIR(mapped, style, size);
 467         } else {
 468             fuir = new FontUIResource(mapped, style, size);
 469         }
 470         return fuir;
 471     }
 472 
 473 
 474     /**
 475      * Used by windows printing to assess if a font is likely to
 476      * be layout compatible with JDK
 477      * TrueType fonts should be, but if they have no GPOS table,
 478      * but do have a GSUB table, then they are probably older
 479      * fonts GDI handles differently.
 480      */
 481     public static boolean textLayoutIsCompatible(Font font) {
 482 
 483         Font2D font2D = getFont2D(font);
 484         if (font2D instanceof TrueTypeFont) {
 485             TrueTypeFont ttf = (TrueTypeFont) font2D;
 486             return
 487                 ttf.getDirectoryEntry(TrueTypeFont.GSUBTag) == null ||
 488                 ttf.getDirectoryEntry(TrueTypeFont.GPOSTag) != null;
 489         } else {
 490             return false;
 491         }
 492     }
 493 
 494 }