update tcl/tk

1 files changed, 3334 insertions, 0 deletions

diff --git a/tk8.6/unix/tkUnixFont.c b/tk8.6/unix/tkUnixFont.c
new file mode 100644
index 0000000..96635b4
--- /dev/null
+++ b/tk8.6/unix/tkUnixFont.c
@@ -0,0 +1,3334 @@
+/*
+ * tkUnixFont.c --
+ *
+ *	Contains the Unix implementation of the platform-independent font
+ *	package interface.
+ *
+ * Copyright (c) 1996-1997 Sun Microsystems, Inc.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+#include "tkUnixInt.h"
+#include "tkFont.h"
+#include <netinet/in.h>		/* for htons() prototype */
+#include <arpa/inet.h>		/* inet_ntoa() */
+
+/*
+ * The preferred font encodings.
+ */
+
+static const char *const encodingList[] = {
+    "iso8859-1", "jis0208", "jis0212", NULL
+};
+
+/*
+ * The following structure represents a font family. It is assumed that all
+ * screen fonts constructed from the same "font family" share certain
+ * properties; all screen fonts with the same "font family" point to a shared
+ * instance of this structure. The most important shared property is the
+ * character existence metrics, used to determine if a screen font can display
+ * a given Unicode character.
+ *
+ * Under Unix, there are three attributes that uniquely identify a "font
+ * family": the foundry, face name, and charset.
+ */
+
+#define FONTMAP_SHIFT		10
+
+#define FONTMAP_PAGES		(1 << (sizeof(Tcl_UniChar)*8 - FONTMAP_SHIFT))
+#define FONTMAP_BITSPERPAGE	(1 << FONTMAP_SHIFT)
+
+typedef struct FontFamily {
+    struct FontFamily *nextPtr;	/* Next in list of all known font families. */
+    int refCount;		/* How many SubFonts are referring to this
+				 * FontFamily. When the refCount drops to
+				 * zero, this FontFamily may be freed. */
+    /*
+     * Key.
+     */
+
+    Tk_Uid foundry;		/* Foundry key for this FontFamily. */
+    Tk_Uid faceName;		/* Face name key for this FontFamily. */
+    Tcl_Encoding encoding;	/* Encoding key for this FontFamily. */
+
+    /*
+     * Derived properties.
+     */
+
+    int isTwoByteFont;		/* 1 if this is a double-byte font, 0
+				 * otherwise. */
+    char *fontMap[FONTMAP_PAGES];
+				/* Two-level sparse table used to determine
+				 * quickly if the specified character exists.
+				 * As characters are encountered, more pages
+				 * in this table are dynamically alloced. The
+				 * contents of each page is a bitmask
+				 * consisting of FONTMAP_BITSPERPAGE bits,
+				 * representing whether this font can be used
+				 * to display the given character at the
+				 * corresponding bit position. The high bits
+				 * of the character are used to pick which
+				 * page of the table is used. */
+} FontFamily;
+
+/*
+ * The following structure encapsulates an individual screen font. A font
+ * object is made up of however many SubFonts are necessary to display a
+ * stream of multilingual characters.
+ */
+
+typedef struct SubFont {
+    char **fontMap;		/* Pointer to font map from the FontFamily,
+				 * cached here to save a dereference. */
+    XFontStruct *fontStructPtr;	/* The specific screen font that will be used
+				 * when displaying/measuring chars belonging
+				 * to the FontFamily. */
+    FontFamily *familyPtr;	/* The FontFamily for this SubFont. */
+} SubFont;
+
+/*
+ * The following structure represents Unix's implementation of a font object.
+ */
+
+#define SUBFONT_SPACE		3
+#define BASE_CHARS		256
+
+typedef struct UnixFont {
+    TkFont font;		/* Stuff used by generic font package. Must be
+				 * first in structure. */
+    SubFont staticSubFonts[SUBFONT_SPACE];
+				/* Builtin space for a limited number of
+				 * SubFonts. */
+    int numSubFonts;		/* Length of following array. */
+    SubFont *subFontArray;	/* Array of SubFonts that have been loaded in
+				 * order to draw/measure all the characters
+				 * encountered by this font so far. All fonts
+				 * start off with one SubFont initialized by
+				 * AllocFont() from the original set of font
+				 * attributes. Usually points to
+				 * staticSubFonts, but may point to malloced
+				 * space if there are lots of SubFonts. */
+    SubFont controlSubFont;	/* Font to use to display control-character
+				 * expansions. */
+
+    Display *display;		/* Display that owns font. */
+    int pixelSize;		/* Original pixel size used when font was
+				 * constructed. */
+    TkXLFDAttributes xa;	/* Additional attributes that specify the
+				 * preferred foundry and encoding to use when
+				 * constructing additional SubFonts. */
+    int widths[BASE_CHARS];	/* Widths of first 256 chars in the base font,
+				 * for handling common case. */
+    int underlinePos;		/* Offset from baseline to origin of underline
+				 * bar (used when drawing underlined font)
+				 * (pixels). */
+    int barHeight;		/* Height of underline or overstrike bar (used
+				 * when drawing underlined or strikeout font)
+				 * (pixels). */
+} UnixFont;
+
+/*
+ * The following structure and definition is used to keep track of the
+ * alternative names for various encodings. Asking for an encoding that
+ * matches one of the alias patterns will result in actually getting the
+ * encoding by its real name.
+ */
+
+typedef struct EncodingAlias {
+    const char *realName;	/* The real name of the encoding to load if
+				 * the provided name matched the pattern. */
+    const char *aliasPattern;	/* Pattern for encoding name, of the form that
+				 * is acceptable to Tcl_StringMatch. */
+} EncodingAlias;
+
+/*
+ * Just some utility structures used for passing around values in helper
+ * functions.
+ */
+
+typedef struct FontAttributes {
+    TkFontAttributes fa;
+    TkXLFDAttributes xa;
+} FontAttributes;
+
+typedef struct ThreadSpecificData {
+    FontFamily *fontFamilyList; /* The list of font families that are
+				 * currently loaded. As screen fonts are
+				 * loaded, this list grows to hold information
+				 * about what characters exist in each font
+				 * family. */
+    FontFamily controlFamily;	/* FontFamily used to handle control character
+				 * expansions. The encoding of this FontFamily
+				 * converts UTF-8 to backslashed escape
+				 * sequences. */
+} ThreadSpecificData;
+static Tcl_ThreadDataKey dataKey;
+
+/*
+ * The set of builtin encoding alises to convert the XLFD names for the
+ * encodings into the names expected by the Tcl encoding package.
+ */
+
+static EncodingAlias encodingAliases[] = {
+    {"gb2312-raw",	"gb2312*"},
+    {"big5",		"big5*"},
+    {"cns11643-1",	"cns11643*-1"},
+    {"cns11643-1",	"cns11643*.1-0"},
+    {"cns11643-2",	"cns11643*-2"},
+    {"cns11643-2",	"cns11643*.2-0"},
+    {"jis0201",		"jisx0201*"},
+    {"jis0201",		"jisx0202*"},
+    {"jis0208",		"jisc6226*"},
+    {"jis0208",		"jisx0208*"},
+    {"jis0212",		"jisx0212*"},
+    {"tis620",		"tis620*"},
+    {"ksc5601",		"ksc5601*"},
+    {"dingbats",	"*dingbats"},
+#ifdef WORDS_BIGENDIAN
+    {"unicode",		"iso10646-1"},
+#else
+    /*
+     * ucs-2be is needed if native order isn't BE.
+     */
+    {"ucs-2be",		"iso10646-1"},
+#endif
+    {NULL,		NULL}
+};
+
+/*
+ * Functions used only in this file.
+ */
+
+static void		FontPkgCleanup(ClientData clientData);
+static FontFamily *	AllocFontFamily(Display *display,
+			    XFontStruct *fontStructPtr, int base);
+static SubFont *	CanUseFallback(UnixFont *fontPtr,
+			    const char *fallbackName, int ch,
+			    SubFont **fixSubFontPtrPtr);
+static SubFont *	CanUseFallbackWithAliases(UnixFont *fontPtr,
+			    const char *fallbackName, int ch,
+			    Tcl_DString *nameTriedPtr,
+			    SubFont **fixSubFontPtrPtr);
+static int		ControlUtfProc(ClientData clientData, const char *src,
+			    int srcLen, int flags, Tcl_EncodingState*statePtr,
+			    char *dst, int dstLen, int *srcReadPtr,
+			    int *dstWrotePtr, int *dstCharsPtr);
+static XFontStruct *	CreateClosestFont(Tk_Window tkwin,
+			    const TkFontAttributes *faPtr,
+			    const TkXLFDAttributes *xaPtr);
+static SubFont *	FindSubFontForChar(UnixFont *fontPtr, int ch,
+			    SubFont **fixSubFontPtrPtr);
+static void		FontMapInsert(SubFont *subFontPtr, int ch);
+static void		FontMapLoadPage(SubFont *subFontPtr, int row);
+static int		FontMapLookup(SubFont *subFontPtr, int ch);
+static void		FreeFontFamily(FontFamily *afPtr);
+static const char *	GetEncodingAlias(const char *name);
+static int		GetFontAttributes(Display *display,
+			    XFontStruct *fontStructPtr, FontAttributes *faPtr);
+static XFontStruct *	GetScreenFont(Display *display,
+			    FontAttributes *wantPtr, char **nameList,
+			    int bestIdx[], unsigned bestScore[]);
+static XFontStruct *	GetSystemFont(Display *display);
+static int		IdentifySymbolEncodings(FontAttributes *faPtr);
+static void		InitFont(Tk_Window tkwin, XFontStruct *fontStructPtr,
+			    UnixFont *fontPtr);
+static void		InitSubFont(Display *display,
+			    XFontStruct *fontStructPtr, int base,
+			    SubFont *subFontPtr);
+static char **		ListFonts(Display *display, const char *faceName,
+			    int *numNamesPtr);
+static char **		ListFontOrAlias(Display *display, const char*faceName,
+			    int *numNamesPtr);
+static unsigned		RankAttributes(FontAttributes *wantPtr,
+			    FontAttributes *gotPtr);
+static void		ReleaseFont(UnixFont *fontPtr);
+static void		ReleaseSubFont(Display *display, SubFont *subFontPtr);
+static int		SeenName(const char *name, Tcl_DString *dsPtr);
+#ifndef WORDS_BIGENDIAN
+static int		Ucs2beToUtfProc(ClientData clientData, const char*src,
+			    int srcLen, int flags, Tcl_EncodingState*statePtr,
+			    char *dst, int dstLen, int *srcReadPtr,
+			    int *dstWrotePtr, int *dstCharsPtr);
+static int		UtfToUcs2beProc(ClientData clientData, const char*src,
+			    int srcLen, int flags, Tcl_EncodingState*statePtr,
+			    char *dst, int dstLen, int *srcReadPtr,
+			    int *dstWrotePtr, int *dstCharsPtr);
+#endif
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * FontPkgCleanup --
+ *
+ *	This function is called when an application is created. It initializes
+ *	all the structures that are used by the platform-dependent code on a
+ *	per application basis.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Releases thread-specific resources used by font pkg.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static void
+FontPkgCleanup(
+    ClientData clientData)
+{
+    ThreadSpecificData *tsdPtr =
+	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
+
+    if (tsdPtr->controlFamily.encoding != NULL) {
+	FontFamily *familyPtr = &tsdPtr->controlFamily;
+	int i;
+
+	Tcl_FreeEncoding(familyPtr->encoding);
+	for (i = 0; i < FONTMAP_PAGES; i++) {
+	    if (familyPtr->fontMap[i] != NULL) {
+		ckfree(familyPtr->fontMap[i]);
+	    }
+	}
+	tsdPtr->controlFamily.encoding = NULL;
+    }
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * TkpFontPkgInit --
+ *
+ *	This function is called when an application is created. It initializes
+ *	all the structures that are used by the platform-dependent code on a
+ *	per application basis.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+void
+TkpFontPkgInit(
+    TkMainInfo *mainPtr)	/* The application being created. */
+{
+    ThreadSpecificData *tsdPtr =
+	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
+    Tcl_EncodingType type;
+    SubFont dummy;
+    int i;
+
+    if (tsdPtr->controlFamily.encoding == NULL) {
+	type.encodingName = "X11ControlChars";
+	type.toUtfProc = ControlUtfProc;
+	type.fromUtfProc = ControlUtfProc;
+	type.freeProc = NULL;
+	type.clientData = NULL;
+	type.nullSize = 0;
+
+	tsdPtr->controlFamily.refCount = 2;
+	tsdPtr->controlFamily.encoding = Tcl_CreateEncoding(&type);
+	tsdPtr->controlFamily.isTwoByteFont = 0;
+
+	dummy.familyPtr = &tsdPtr->controlFamily;
+	dummy.fontMap = tsdPtr->controlFamily.fontMap;
+	for (i = 0x00; i < 0x20; i++) {
+	    FontMapInsert(&dummy, i);
+	    FontMapInsert(&dummy, i + 0x80);
+	}
+
+#ifndef WORDS_BIGENDIAN
+	/*
+	 * UCS-2BE is unicode (UCS-2) in big-endian format. Define this if
+	 * native order isn't BE. It is used in iso10646 fonts.
+	 */
+
+	type.encodingName = "ucs-2be";
+	type.toUtfProc = Ucs2beToUtfProc;
+	type.fromUtfProc = UtfToUcs2beProc;
+	type.freeProc = NULL;
+	type.clientData = NULL;
+	type.nullSize = 2;
+	Tcl_CreateEncoding(&type);
+#endif
+	Tcl_CreateThreadExitHandler(FontPkgCleanup, NULL);
+    }
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * ControlUtfProc --
+ *
+ *	Convert from UTF-8 into the ASCII expansion of a control character.
+ *
+ * Results:
+ *	Returns TCL_OK if conversion was successful.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static int
+ControlUtfProc(
+    ClientData clientData,	/* Not used. */
+    const char *src,		/* Source string in UTF-8. */
+    int srcLen,			/* Source string length in bytes. */
+    int flags,			/* Conversion control flags. */
+    Tcl_EncodingState *statePtr,/* Place for conversion routine to store state
+				 * information used during a piecewise
+				 * conversion. Contents of statePtr are
+				 * initialized and/or reset by conversion
+				 * routine under control of flags argument. */
+    char *dst,			/* Output buffer in which converted string is
+				 * stored. */
+    int dstLen,			/* The maximum length of output buffer in
+				 * bytes. */
+    int *srcReadPtr,		/* Filled with the number of bytes from the
+				 * source string that were converted. This may
+				 * be less than the original source length if
+				 * there was a problem converting some source
+				 * characters. */
+    int *dstWrotePtr,		/* Filled with the number of bytes that were
+				 * stored in the output buffer as a result of
+				 * the conversion. */
+    int *dstCharsPtr)		/* Filled with the number of characters that
+				 * correspond to the bytes stored in the
+				 * output buffer. */
+{
+    const char *srcStart, *srcEnd;
+    char *dstStart, *dstEnd;
+    int ch, result;
+    static char hexChars[] = "0123456789abcdef";
+    static char mapChars[] = {
+	0, 0, 0, 0, 0, 0, 0,
+	'a', 'b', 't', 'n', 'v', 'f', 'r'
+    };
+
+    result = TCL_OK;
+
+    srcStart = src;
+    srcEnd = src + srcLen;
+
+    dstStart = dst;
+    dstEnd = dst + dstLen - 6;
+
+    for ( ; src < srcEnd; ) {
+	if (dst > dstEnd) {
+	    result = TCL_CONVERT_NOSPACE;
+	    break;
+	}
+	src += TkUtfToUniChar(src, &ch);
+	dst[0] = '\\';
+	if (((size_t) ch < sizeof(mapChars)) && (mapChars[ch] != 0)) {
+	    dst[1] = mapChars[ch];
+	    dst += 2;
+	} else if (ch < 256) {
+	    dst[1] = 'x';
+	    dst[2] = hexChars[(ch >> 4) & 0xf];
+	    dst[3] = hexChars[ch & 0xf];
+	    dst += 4;
+	} else if (ch < 0x10000) {
+	    dst[1] = 'u';
+	    dst[2] = hexChars[(ch >> 12) & 0xf];
+	    dst[3] = hexChars[(ch >> 8) & 0xf];
+	    dst[4] = hexChars[(ch >> 4) & 0xf];
+	    dst[5] = hexChars[ch & 0xf];
+	    dst += 6;
+	} else {
+	    /* TODO we can do better here */
+	    dst[1] = 'u';
+	    dst[2] = 'f';
+	    dst[3] = 'f';
+	    dst[4] = 'f';
+	    dst[5] = 'd';
+	    dst += 6;
+	}
+    }
+    *srcReadPtr = src - srcStart;
+    *dstWrotePtr = dst - dstStart;
+    *dstCharsPtr = dst - dstStart;
+    return result;
+}
+
+#ifndef WORDS_BIGENDIAN
+/*
+ *-------------------------------------------------------------------------
+ *
+ * Ucs2beToUtfProc --
+ *
+ *	Convert from UCS-2BE (big-endian 16-bit Unicode) to UTF-8.
+ *	This is only defined on LE machines.
+ *
+ * Results:
+ *	Returns TCL_OK if conversion was successful.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static int
+Ucs2beToUtfProc(
+    ClientData clientData,	/* Not used. */
+    const char *src,		/* Source string in Unicode. */
+    int srcLen,			/* Source string length in bytes. */
+    int flags,			/* Conversion control flags. */
+    Tcl_EncodingState *statePtr,/* Place for conversion routine to store state
+				 * information used during a piecewise
+				 * conversion. Contents of statePtr are
+				 * initialized and/or reset by conversion
+				 * routine under control of flags argument. */
+    char *dst,			/* Output buffer in which converted string is
+				 * stored. */
+    int dstLen,			/* The maximum length of output buffer in
+				 * bytes. */
+    int *srcReadPtr,		/* Filled with the number of bytes from the
+				 * source string that were converted. This may
+				 * be less than the original source length if
+				 * there was a problem converting some source
+				 * characters. */
+    int *dstWrotePtr,		/* Filled with the number of bytes that were
+				 * stored in the output buffer as a result of
+				 * the conversion. */
+    int *dstCharsPtr)		/* Filled with the number of characters that
+				 * correspond to the bytes stored in the
+				 * output buffer. */
+{
+    const char *srcStart, *srcEnd;
+    char *dstEnd, *dstStart;
+    int result, numChars;
+
+    result = TCL_OK;
+
+    /* check alignment with ucs-2 (2 == sizeof(UCS-2)) */
+    if ((srcLen % 2) != 0) {
+	result = TCL_CONVERT_MULTIBYTE;
+	srcLen--;
+    }
+
+    srcStart = src;
+    srcEnd = src + srcLen;
+
+    dstStart = dst;
+    dstEnd = dst + dstLen - TCL_UTF_MAX;
+
+    for (numChars = 0; src < srcEnd; numChars++) {
+	if (dst > dstEnd) {
+	    result = TCL_CONVERT_NOSPACE;
+	    break;
+	}
+
+	/*
+	 * Need to swap byte-order on little-endian machines (x86) for
+	 * UCS-2BE. We know this is an LE->BE swap.
+	 */
+
+	dst += Tcl_UniCharToUtf(htons(*((short *)src)), dst);
+	src += 2 /* sizeof(UCS-2) */;
+    }
+
+    *srcReadPtr = src - srcStart;
+    *dstWrotePtr = dst - dstStart;
+    *dstCharsPtr = numChars;
+    return result;
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * UtfToUcs2beProc --
+ *
+ *	Convert from UTF-8 to UCS-2BE (fixed 2-byte encoding).
+ *
+ * Results:
+ *	Returns TCL_OK if conversion was successful.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static int
+UtfToUcs2beProc(
+    ClientData clientData,	/* TableEncodingData that specifies
+				 * encoding. */
+    const char *src,		/* Source string in UTF-8. */
+    int srcLen,			/* Source string length in bytes. */
+    int flags,			/* Conversion control flags. */
+    Tcl_EncodingState *statePtr,/* Place for conversion routine to store state
+				 * information used during a piecewise
+				 * conversion. Contents of statePtr are
+				 * initialized and/or reset by conversion
+				 * routine under control of flags argument. */
+    char *dst,			/* Output buffer in which converted string is
+				 * stored. */
+    int dstLen,			/* The maximum length of output buffer in
+				 * bytes. */
+    int *srcReadPtr,		/* Filled with the number of bytes from the
+				 * source string that were converted. This may
+				 * be less than the original source length if
+				 * there was a problem converting some source
+				 * characters. */
+    int *dstWrotePtr,		/* Filled with the number of bytes that were
+				 * stored in the output buffer as a result of
+				 * the conversion. */
+    int *dstCharsPtr)		/* Filled with the number of characters that
+				 * correspond to the bytes stored in the
+				 * output buffer. */
+{
+    const char *srcStart, *srcEnd, *srcClose, *dstStart, *dstEnd;
+    int result, numChars;
+    Tcl_UniChar ch;
+
+    srcStart = src;
+    srcEnd = src + srcLen;
+    srcClose = srcEnd;
+    if (!(flags & TCL_ENCODING_END)) {
+	srcClose -= TCL_UTF_MAX;
+    }
+
+    dstStart = dst;
+    dstEnd = dst + dstLen - 2 /* sizeof(UCS-2) */;
+
+    result = TCL_OK;
+    for (numChars = 0; src < srcEnd; numChars++) {
+	if ((src > srcClose) && (!Tcl_UtfCharComplete(src, srcEnd - src))) {
+	    /*
+	     * If there is more string to follow, this will ensure that the
+	     * last UTF-8 character in the source buffer hasn't been cut off.
+	     */
+
+	    result = TCL_CONVERT_MULTIBYTE;
+	    break;
+	}
+	if (dst > dstEnd) {
+	    result = TCL_CONVERT_NOSPACE;
+	    break;
+        }
+	src += Tcl_UtfToUniChar(src, &ch);
+
+	/*
+	 * Ensure big-endianness (store big bits first).
+	 * XXX: This hard-codes the assumed size of Tcl_UniChar as 2. Make
+	 * sure to work in char* for Tcl_UtfToUniChar alignment. [Bug 1122671]
+	 */
+
+	*dst++ = (ch >> 8);
+	*dst++ = (ch & 0xFF);
+    }
+    *srcReadPtr = src - srcStart;
+    *dstWrotePtr = dst - dstStart;
+    *dstCharsPtr = numChars;
+    return result;
+}
+#endif /* WORDS_BIGENDIAN */
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * TkpGetNativeFont --
+ *
+ *	Map a platform-specific native font name to a TkFont.
+ *
+ * Results:
+ *	The return value is a pointer to a TkFont that represents the native
+ *	font. If a native font by the given name could not be found, the
+ *	return value is NULL.
+ *
+ *	Every call to this function returns a new TkFont structure, even if
+ *	the name has already been seen before. The caller should call
+ *	TkpDeleteFont() when the font is no longer needed.
+ *
+ *	The caller is responsible for initializing the memory associated with
+ *	the generic TkFont when this function returns and releasing the
+ *	contents of the generic TkFont before calling TkpDeleteFont().
+ *
+ * Side effects:
+ *	Memory allocated.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+TkFont *
+TkpGetNativeFont(
+    Tk_Window tkwin,		/* For display where font will be used. */
+    const char *name)		/* Platform-specific font name. */
+{
+    UnixFont *fontPtr;
+    XFontStruct *fontStructPtr;
+    FontAttributes fa;
+    const char *p;
+    int hasSpace, dashes, hasWild;
+
+    /*
+     * The behavior of X when given a name that isn't an XLFD is unspecified.
+     * For example, Exceed 6 returns a valid font for any random string. This
+     * is awkward since system names have higher priority than the other Tk
+     * font syntaxes. So, we need to perform a quick sanity check on the name
+     * and fail if it looks suspicious. We fail if the name:
+     *     - contains a space immediately before a dash
+     *	   - contains a space, but no '*' characters and fewer than 14 dashes
+     */
+
+    hasSpace = dashes = hasWild = 0;
+    for (p = name; *p != '\0'; p++) {
+	if (*p == ' ') {
+	    if (p[1] == '-') {
+		return NULL;
+	    }
+	    hasSpace = 1;
+	} else if (*p == '-') {
+	    dashes++;
+	} else if (*p == '*') {
+	    hasWild = 1;
+	}
+    }
+    if ((dashes < 14) && !hasWild && hasSpace) {
+	return NULL;
+    }
+
+    fontStructPtr = XLoadQueryFont(Tk_Display(tkwin), name);
+    if (fontStructPtr == NULL) {
+	/*
+	 * Handle all names that look like XLFDs here. Otherwise, when
+	 * TkpGetFontFromAttributes is called from generic code, any foundry
+	 * or encoding information specified in the XLFD will have been parsed
+	 * out and lost. But make sure we don't have an "-option value" string
+	 * since TkFontParseXLFD would return a false success when attempting
+	 * to parse it.
+	 */
+
+	if (name[0] == '-') {
+	    if (name[1] != '*') {
+		char *dash;
+
+		dash = strchr(name + 1, '-');
+		if ((dash == NULL) || (isspace(UCHAR(dash[-1])))) {
+		    return NULL;
+		}
+	    }
+	} else if (name[0] != '*') {
+	    return NULL;
+	}
+	if (TkFontParseXLFD(name, &fa.fa, &fa.xa) != TCL_OK) {
+	    return NULL;
+	}
+	fontStructPtr = CreateClosestFont(tkwin, &fa.fa, &fa.xa);
+    }
+    fontPtr = ckalloc(sizeof(UnixFont));
+    InitFont(tkwin, fontStructPtr, fontPtr);
+
+    return (TkFont *) fontPtr;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * TkpGetFontFromAttributes --
+ *
+ *	Given a desired set of attributes for a font, find a font with the
+ *	closest matching attributes.
+ *
+ * Results:
+ *	The return value is a pointer to a TkFont that represents the font
+ *	with the desired attributes. If a font with the desired attributes
+ *	could not be constructed, some other font will be substituted
+ *	automatically.
+ *
+ *	Every call to this function returns a new TkFont structure, even if
+ *	the specified attributes have already been seen before. The caller
+ *	should call TkpDeleteFont() to free the platform- specific data when
+ *	the font is no longer needed.
+ *
+ *	The caller is responsible for initializing the memory associated with
+ *	the generic TkFont when this function returns and releasing the
+ *	contents of the generic TkFont before calling TkpDeleteFont().
+ *
+ * Side effects:
+ *	Memory allocated.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+TkFont *
+TkpGetFontFromAttributes(
+    TkFont *tkFontPtr,		/* If non-NULL, store the information in this
+				 * existing TkFont structure, rather than
+				 * allocating a new structure to hold the
+				 * font; the existing contents of the font
+				 * will be released. If NULL, a new TkFont
+				 * structure is allocated. */
+    Tk_Window tkwin,		/* For display where font will be used. */
+    const TkFontAttributes *faPtr)
+				/* Set of attributes to match. */
+{
+    UnixFont *fontPtr;
+    TkXLFDAttributes xa;
+    XFontStruct *fontStructPtr;
+
+    TkInitXLFDAttributes(&xa);
+    fontStructPtr = CreateClosestFont(tkwin, faPtr, &xa);
+
+    fontPtr = (UnixFont *) tkFontPtr;
+    if (fontPtr == NULL) {
+	fontPtr = ckalloc(sizeof(UnixFont));
+    } else {
+	ReleaseFont(fontPtr);
+    }
+    InitFont(tkwin, fontStructPtr, fontPtr);
+
+    fontPtr->font.fa.underline = faPtr->underline;
+    fontPtr->font.fa.overstrike = faPtr->overstrike;
+
+    return (TkFont *) fontPtr;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * TkpDeleteFont --
+ *
+ *	Called to release a font allocated by TkpGetNativeFont() or
+ *	TkpGetFontFromAttributes(). The caller should have already released
+ *	the fields of the TkFont that are used exclusively by the generic
+ *	TkFont code.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	TkFont is deallocated.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+void
+TkpDeleteFont(
+    TkFont *tkFontPtr)		/* Token of font to be deleted. */
+{
+    UnixFont *fontPtr = (UnixFont *) tkFontPtr;
+
+    ReleaseFont(fontPtr);
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * TkpGetFontFamilies --
+ *
+ *	Return information about the font families that are available on the
+ *	display of the given window.
+ *
+ * Results:
+ *	Modifies interp's result object to hold a list of all the available
+ *	font families.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+void
+TkpGetFontFamilies(
+    Tcl_Interp *interp,		/* Interp to hold result. */
+    Tk_Window tkwin)		/* For display to query. */
+{
+    int i, new, numNames;
+    char *family, **nameList;
+    Tcl_HashTable familyTable;
+    Tcl_HashEntry *hPtr;
+    Tcl_HashSearch search;
+    Tcl_Obj *resultPtr, *strPtr;
+
+    Tcl_InitHashTable(&familyTable, TCL_STRING_KEYS);
+    nameList = ListFonts(Tk_Display(tkwin), "*", &numNames);
+    for (i = 0; i < numNames; i++) {
+	char *familyEnd;
+
+	family = strchr(nameList[i] + 1, '-');
+	if (family == NULL) {
+	    /*
+	     * Apparently, sometimes ListFonts() can return a font name with
+	     * zero or one '-' character in it. This is probably indicative of
+	     * a server misconfiguration, but crashing because of it is a very
+	     * bad idea anyway. [Bug 1475865]
+	     */
+
+	    continue;
+	}
+	family++;			/* Advance to char after '-'. */
+	familyEnd = strchr(family, '-');
+	if (familyEnd == NULL) {
+	    continue;			/* See comment above. */
+	}
+	*familyEnd = '\0';
+	Tcl_CreateHashEntry(&familyTable, family, &new);
+    }
+    XFreeFontNames(nameList);
+
+    hPtr = Tcl_FirstHashEntry(&familyTable, &search);
+    resultPtr = Tcl_NewObj();
+    while (hPtr != NULL) {
+	strPtr = Tcl_NewStringObj(Tcl_GetHashKey(&familyTable, hPtr), -1);
+	Tcl_ListObjAppendElement(NULL, resultPtr, strPtr);
+	hPtr = Tcl_NextHashEntry(&search);
+    }
+    Tcl_SetObjResult(interp, resultPtr);
+
+    Tcl_DeleteHashTable(&familyTable);
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * TkpGetSubFonts --
+ *
+ *	A function used by the testing package for querying the actual screen
+ *	fonts that make up a font object.
+ *
+ * Results:
+ *	Modifies interp's result object to hold a list containing the names of
+ *	the screen fonts that make up the given font object.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+void
+TkpGetSubFonts(
+    Tcl_Interp *interp,
+    Tk_Font tkfont)
+{
+    int i;
+    Tcl_Obj *objv[3], *resultPtr, *listPtr;
+    UnixFont *fontPtr;
+    FontFamily *familyPtr;
+
+    resultPtr = Tcl_NewObj();
+    fontPtr = (UnixFont *) tkfont;
+    for (i = 0; i < fontPtr->numSubFonts; i++) {
+	familyPtr = fontPtr->subFontArray[i].familyPtr;
+	objv[0] = Tcl_NewStringObj(familyPtr->faceName, -1);
+	objv[1] = Tcl_NewStringObj(familyPtr->foundry, -1);
+	objv[2] = Tcl_NewStringObj(
+		Tcl_GetEncodingName(familyPtr->encoding), -1);
+	listPtr = Tcl_NewListObj(3, objv);
+	Tcl_ListObjAppendElement(NULL, resultPtr, listPtr);
+    }
+    Tcl_SetObjResult(interp, resultPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TkpGetFontAttrsForChar --
+ *
+ *	Retrieve the font attributes of the actual font used to render a given
+ *	character.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The font attributes are stored in *faPtr.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TkpGetFontAttrsForChar(
+    Tk_Window tkwin,		/* Window on the font's display */
+    Tk_Font tkfont,		/* Font to query */
+    int c,         		/* Character of interest */
+    TkFontAttributes *faPtr)	/* Output: Font attributes */
+{
+    FontAttributes atts;
+    UnixFont *fontPtr = (UnixFont *) tkfont;
+				/* Structure describing the logical font */
+    SubFont *lastSubFontPtr = &fontPtr->subFontArray[0];
+				/* Pointer to subfont array in case
+				 * FindSubFontForChar needs to fix up the
+				 * memory allocation */
+    SubFont *thisSubFontPtr = FindSubFontForChar(fontPtr, c, &lastSubFontPtr);
+				/* Pointer to the subfont to use for the given
+				 * character */
+
+    GetFontAttributes(Tk_Display(tkwin), thisSubFontPtr->fontStructPtr, &atts);
+    *faPtr = atts.fa;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * Tk_MeasureChars --
+ *
+ *	Determine the number of characters from the string that will fit in
+ *	the given horizontal span. The measurement is done under the
+ *	assumption that Tk_DrawChars() will be used to actually display the
+ *	characters.
+ *
+ * Results:
+ *	The return value is the number of bytes from source that fit into the
+ *	span that extends from 0 to maxLength. *lengthPtr is filled with the
+ *	x-coordinate of the right edge of the last character that did fit.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+int
+Tk_MeasureChars(
+    Tk_Font tkfont,		/* Font in which characters will be drawn. */
+    const char *source,		/* UTF-8 string to be displayed. Need not be
+				 * '\0' terminated. */
+    int numBytes,		/* Maximum number of bytes to consider from
+				 * source string. */
+    int maxLength,		/* If >= 0, maxLength specifies the longest
+				 * permissible line length in pixels; don't
+				 * consider any character that would cross
+				 * this x-position. If < 0, then line length
+				 * is unbounded and the flags argument is
+				 * ignored. */
+    int flags,			/* Various flag bits OR-ed together:
+				 * TK_PARTIAL_OK means include the last char
+				 * which only partially fit on this line.
+				 * TK_WHOLE_WORDS means stop on a word
+				 * boundary, if possible. TK_AT_LEAST_ONE
+				 * means return at least one character even if
+				 * no characters fit. */
+    int *lengthPtr)		/* Filled with x-location just after the
+				 * terminating character. */
+{
+    UnixFont *fontPtr;
+    SubFont *lastSubFontPtr;
+    int curX, curByte, ch;
+
+    /*
+     * Unix does not use kerning or fractional character widths when
+     * displaying text on the screen. So that means we can safely measure
+     * individual characters or spans of characters and add up the widths w/o
+     * any "off-by-one-pixel" errors.
+     */
+
+    fontPtr = (UnixFont *) tkfont;
+
+    lastSubFontPtr = &fontPtr->subFontArray[0];
+
+    if (numBytes == 0) {
+	curX = 0;
+	curByte = 0;
+    } else if (maxLength < 0) {
+	const char *p, *end, *next;
+	SubFont *thisSubFontPtr;
+	FontFamily *familyPtr;
+	Tcl_DString runString;
+
+	/*
+	 * A three step process:
+	 * 1. Find a contiguous range of characters that can all be
+	 *    represented by a single screen font.
+	 * 2. Convert those chars to the encoding of that font.
+	 * 3. Measure converted chars.
+	 */
+
+	curX = 0;
+	end = source + numBytes;
+	for (p = source; p < end; ) {
+	    next = p + TkUtfToUniChar(p, &ch);
+	    thisSubFontPtr = FindSubFontForChar(fontPtr, ch, &lastSubFontPtr);
+	    if (thisSubFontPtr != lastSubFontPtr) {
+		familyPtr = lastSubFontPtr->familyPtr;
+		Tcl_UtfToExternalDString(familyPtr->encoding, source,
+			p - source, &runString);
+		if (familyPtr->isTwoByteFont) {
+		    curX += XTextWidth16(lastSubFontPtr->fontStructPtr,
+			    (XChar2b *) Tcl_DStringValue(&runString),
+			    Tcl_DStringLength(&runString) / 2);
+		} else {
+		    curX += XTextWidth(lastSubFontPtr->fontStructPtr,
+			    Tcl_DStringValue(&runString),
+			    Tcl_DStringLength(&runString));
+		}
+		Tcl_DStringFree(&runString);
+		lastSubFontPtr = thisSubFontPtr;
+		source = p;
+	    }
+	    p = next;
+	}
+	familyPtr = lastSubFontPtr->familyPtr;
+	Tcl_UtfToExternalDString(familyPtr->encoding, source, p - source,
+		&runString);
+	if (familyPtr->isTwoByteFont) {
+	    curX += XTextWidth16(lastSubFontPtr->fontStructPtr,
+		    (XChar2b *) Tcl_DStringValue(&runString),
+		    Tcl_DStringLength(&runString) >> 1);
+	} else {
+	    curX += XTextWidth(lastSubFontPtr->fontStructPtr,
+		    Tcl_DStringValue(&runString),
+		    Tcl_DStringLength(&runString));
+	}
+	Tcl_DStringFree(&runString);
+	curByte = numBytes;
+    } else {
+	const char *p, *end, *next, *term;
+	int newX, termX, sawNonSpace, dstWrote;
+	FontFamily *familyPtr;
+	XChar2b buf[8];
+
+	/*
+	 * How many chars will fit in the space allotted? This first version
+	 * may be inefficient because it measures every character
+	 * individually.
+	 */
+
+	next = source + TkUtfToUniChar(source, &ch);
+	newX = curX = termX = 0;
+
+	term = source;
+	end = source + numBytes;
+
+	sawNonSpace = (ch > 255) || !isspace(ch);
+	familyPtr = lastSubFontPtr->familyPtr;
+	for (p = source; ; ) {
+	    if ((ch < BASE_CHARS) && (fontPtr->widths[ch] != 0)) {
+		newX += fontPtr->widths[ch];
+	    } else {
+		lastSubFontPtr = FindSubFontForChar(fontPtr, ch, NULL);
+		familyPtr = lastSubFontPtr->familyPtr;
+		Tcl_UtfToExternal(NULL, familyPtr->encoding, p, next - p, 0, NULL,
+			(char *)&buf[0].byte1, sizeof(buf), NULL, &dstWrote, NULL);
+		if (familyPtr->isTwoByteFont) {
+		    newX += XTextWidth16(lastSubFontPtr->fontStructPtr,
+			    buf, dstWrote >> 1);
+		} else {
+		    newX += XTextWidth(lastSubFontPtr->fontStructPtr,
+			    (char *)&buf[0].byte1, dstWrote);
+		}
+	    }
+	    if (newX > maxLength) {
+		break;
+	    }
+	    curX = newX;
+	    p = next;
+	    if (p >= end) {
+		term = end;
+		termX = curX;
+		break;
+	    }
+
+	    next += TkUtfToUniChar(next, &ch);
+	    if ((ch < 256) && isspace(ch)) {
+		if (sawNonSpace) {
+		    term = p;
+		    termX = curX;
+		    sawNonSpace = 0;
+		}
+	    } else {
+		sawNonSpace = 1;
+	    }
+	}
+
+	/*
+	 * P points to the first character that doesn't fit in the desired
+	 * span. Use the flags to figure out what to return.
+	 */
+
+	if ((flags & TK_PARTIAL_OK) && (p < end) && (curX < maxLength)) {
+	    /*
+	     * Include the first character that didn't quite fit in the
+	     * desired span. The width returned will include the width of that
+	     * extra character.
+	     */
+
+	    curX = newX;
+	    p += TkUtfToUniChar(p, &ch);
+	}
+	if ((flags & TK_AT_LEAST_ONE) && (term == source) && (p < end)) {
+	    term = p;
+	    termX = curX;
+	    if (term == source) {
+		term += TkUtfToUniChar(term, &ch);
+		termX = newX;
+	    }
+	} else if ((p >= end) || !(flags & TK_WHOLE_WORDS)) {
+	    term = p;
+	    termX = curX;
+	}
+
+	curX = termX;
+	curByte = term - source;
+    }
+
+    *lengthPtr = curX;
+    return curByte;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * TkpMeasureCharsInContext --
+ *
+ *	Determine the number of bytes from the string that will fit in the
+ *	given horizontal span. The measurement is done under the assumption
+ *	that TkpDrawCharsInContext() will be used to actually display the
+ *	characters.
+ *
+ *	This one is almost the same as Tk_MeasureChars(), but with access to
+ *	all the characters on the line for context. On X11 this context isn't
+ *	consulted, so we just call Tk_MeasureChars().
+ *
+ * Results:
+ *	The return value is the number of bytes from source that fit into the
+ *	span that extends from 0 to maxLength. *lengthPtr is filled with the
+ *	x-coordinate of the right edge of the last character that did fit.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+int
+TkpMeasureCharsInContext(
+    Tk_Font tkfont,		/* Font in which characters will be drawn. */
+    const char *source,		/* UTF-8 string to be displayed. Need not be
+				 * '\0' terminated. */
+    int numBytes,		/* Maximum number of bytes to consider from
+				 * source string in all. */
+    int rangeStart,		/* Index of first byte to measure. */
+    int rangeLength,		/* Length of range to measure in bytes. */
+    int maxLength,		/* If >= 0, maxLength specifies the longest
+				 * permissible line length; don't consider any
+				 * character that would cross this x-position.
+				 * If < 0, then line length is unbounded and
+				 * the flags argument is ignored. */
+    int flags,			/* Various flag bits OR-ed together:
+				 * TK_PARTIAL_OK means include the last char
+				 * which only partially fit on this line.
+				 * TK_WHOLE_WORDS means stop on a word
+				 * boundary, if possible. TK_AT_LEAST_ONE
+				 * means return at least one character even if
+				 * no characters fit. TK_ISOLATE_END means
+				 * that the last character should not be
+				 * considered in context with the rest of the
+				 * string (used for breaking lines). */
+    int *lengthPtr)		/* Filled with x-location just after the
+				 * terminating character. */
+{
+    (void) numBytes; /*unused*/
+    return Tk_MeasureChars(tkfont, source + rangeStart, rangeLength,
+	    maxLength, flags, lengthPtr);
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * Tk_DrawChars --
+ *
+ *	Draw a string of characters on the screen. Tk_DrawChars() expands
+ *	control characters that occur in the string to \xNN sequences.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Information gets drawn on the screen.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+void
+Tk_DrawChars(
+    Display *display,		/* Display on which to draw. */
+    Drawable drawable,		/* Window or pixmap in which to draw. */
+    GC gc,			/* Graphics context for drawing characters. */
+    Tk_Font tkfont,		/* Font in which characters will be drawn;
+				 * must be the same as font used in GC. */
+    const char *source,		/* UTF-8 string to be displayed. Need not be
+				 * '\0' terminated. All Tk meta-characters
+				 * (tabs, control characters, and newlines)
+				 * should be stripped out of the string that
+				 * is passed to this function. If they are not
+				 * stripped out, they will be displayed as
+				 * regular printing characters. */
+    int numBytes,		/* Number of bytes in string. */
+    int x, int y)		/* Coordinates at which to place origin of
+				 * string when drawing. */
+{
+    UnixFont *fontPtr = (UnixFont *) tkfont;
+    SubFont *thisSubFontPtr, *lastSubFontPtr;
+    Tcl_DString runString;
+    const char *p, *end, *next;
+    int xStart, needWidth, window_width, do_width, ch;
+    FontFamily *familyPtr;
+#ifdef TK_DRAW_CHAR_XWINDOW_CHECK
+    int rx, ry;
+    unsigned width, height, border_width, depth;
+    Drawable root;
+#endif
+
+    lastSubFontPtr = &fontPtr->subFontArray[0];
+    xStart = x;
+
+#ifdef TK_DRAW_CHAR_XWINDOW_CHECK
+    /*
+     * Get the window width so we can abort drawing outside of the window
+     */
+
+    if (XGetGeometry(display, drawable, &root, &rx, &ry, &width, &height,
+	    &border_width, &depth) == False) {
+	window_width = INT_MAX;
+    } else {
+	window_width = width;
+    }
+#else
+    /*
+     * This is used by default until we find a solution that doesn't do a
+     * round-trip to the X server (needed to get Tk cached window width).
+     */
+
+    window_width = 32768;
+#endif
+
+    end = source + numBytes;
+    needWidth = fontPtr->font.fa.underline + fontPtr->font.fa.overstrike;
+    for (p = source; p <= end; ) {
+	if (p < end) {
+	    next = p + TkUtfToUniChar(p, &ch);
+	    thisSubFontPtr = FindSubFontForChar(fontPtr, ch, &lastSubFontPtr);
+	} else {
+	    next = p + 1;
+	    thisSubFontPtr = lastSubFontPtr;
+	}
+	if ((thisSubFontPtr != lastSubFontPtr)
+		|| (p == end) || (p-source > 200)) {
+	    if (p > source) {
+		do_width = (needWidth || (p != end)) ? 1 : 0;
+		familyPtr = lastSubFontPtr->familyPtr;
+
+		Tcl_UtfToExternalDString(familyPtr->encoding, source,
+			p - source, &runString);
+		if (familyPtr->isTwoByteFont) {
+		    XDrawString16(display, drawable, gc, x, y,
+			    (XChar2b *) Tcl_DStringValue(&runString),
+			    Tcl_DStringLength(&runString) / 2);
+		    if (do_width) {
+			x += XTextWidth16(lastSubFontPtr->fontStructPtr,
+				(XChar2b *) Tcl_DStringValue(&runString),
+				Tcl_DStringLength(&runString) / 2);
+		    }
+		} else {
+		    XDrawString(display, drawable, gc, x, y,
+			    Tcl_DStringValue(&runString),
+			    Tcl_DStringLength(&runString));
+		    if (do_width) {
+			x += XTextWidth(lastSubFontPtr->fontStructPtr,
+				Tcl_DStringValue(&runString),
+				Tcl_DStringLength(&runString));
+		    }
+		}
+		Tcl_DStringFree(&runString);
+	    }
+	    lastSubFontPtr = thisSubFontPtr;
+	    source = p;
+	    XSetFont(display, gc, lastSubFontPtr->fontStructPtr->fid);
+	    if (x > window_width) {
+		break;
+	    }
+	}
+	p = next;
+    }
+
+    if (lastSubFontPtr != &fontPtr->subFontArray[0]) {
+	XSetFont(display, gc, fontPtr->subFontArray[0].fontStructPtr->fid);
+    }
+
+    if (fontPtr->font.fa.underline != 0) {
+	XFillRectangle(display, drawable, gc, xStart,
+		y + fontPtr->underlinePos,
+		(unsigned) (x - xStart), (unsigned) fontPtr->barHeight);
+    }
+    if (fontPtr->font.fa.overstrike != 0) {
+	y -= fontPtr->font.fm.descent + (fontPtr->font.fm.ascent) / 10;
+	XFillRectangle(display, drawable, gc, xStart, y,
+		(unsigned) (x - xStart), (unsigned) fontPtr->barHeight);
+    }
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * TkpDrawCharsInContext --
+ *
+ *	Draw a string of characters on the screen like Tk_DrawChars(), but
+ *	with access to all the characters on the line for context. On X11 this
+ *	context isn't consulted, so we just call Tk_DrawChars().
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Information gets drawn on the screen.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+void
+TkpDrawCharsInContext(
+    Display *display,		/* Display on which to draw. */
+    Drawable drawable,		/* Window or pixmap in which to draw. */
+    GC gc,			/* Graphics context for drawing characters. */
+    Tk_Font tkfont,		/* Font in which characters will be drawn;
+				 * must be the same as font used in GC. */
+    const char *source,		/* UTF-8 string to be displayed. Need not be
+				 * '\0' terminated. All Tk meta-characters
+				 * (tabs, control characters, and newlines)
+				 * should be stripped out of the string that
+				 * is passed to this function. If they are not
+				 * stripped out, they will be displayed as
+				 * regular printing characters. */
+    int numBytes,		/* Number of bytes in string. */
+    int rangeStart,		/* Index of first byte to draw. */
+    int rangeLength,		/* Length of range to draw in bytes. */
+    int x, int y)		/* Coordinates at which to place origin of the
+				 * whole (not just the range) string when
+				 * drawing. */
+{
+    int widthUntilStart;
+
+    (void) numBytes; /*unused*/
+
+    Tk_MeasureChars(tkfont, source, rangeStart, -1, 0, &widthUntilStart);
+    Tk_DrawChars(display, drawable, gc, tkfont, source + rangeStart,
+	    rangeLength, x+widthUntilStart, y);
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * CreateClosestFont --
+ *
+ *	Helper for TkpGetNativeFont() and TkpGetFontFromAttributes(). Given a
+ *	set of font attributes, construct a close XFontStruct. If requested
+ *	face name is not available, automatically substitutes an alias for
+ *	requested face name. If encoding is not specified (or the requested
+ *	one is not available), automatically chooses another encoding from the
+ *	list of preferred encodings. If the foundry is not specified (or is
+ *	not available) automatically prefers "adobe" foundry. For all other
+ *	attributes, if the requested value was not available, the appropriate
+ *	"close" value will be used.
+ *
+ * Results:
+ *	Return value is the XFontStruct that best matched the requested
+ *	attributes. The return value is never NULL; some font will always be
+ *	returned.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static XFontStruct *
+CreateClosestFont(
+    Tk_Window tkwin,		/* For display where font will be used. */
+    const TkFontAttributes *faPtr,
+				/* Set of generic attributes to match. */
+    const TkXLFDAttributes *xaPtr)
+				/* Set of X-specific attributes to match. */
+{
+    FontAttributes want;
+    char **nameList;
+    int numNames, nameIdx, bestIdx[2];
+    Display *display;
+    XFontStruct *fontStructPtr;
+    unsigned bestScore[2];
+
+    want.fa = *faPtr;
+    want.xa = *xaPtr;
+
+    if (want.xa.foundry == NULL) {
+	want.xa.foundry = Tk_GetUid("adobe");
+    }
+    if (want.fa.family == NULL) {
+	want.fa.family = Tk_GetUid("fixed");
+    }
+    want.fa.size = -TkFontGetPixels(tkwin, faPtr->size);
+    if (want.xa.charset == NULL || *want.xa.charset == '\0') {
+	want.xa.charset = Tk_GetUid("iso8859-1");	/* locale. */
+    }
+
+    display = Tk_Display(tkwin);
+
+    /*
+     * Algorithm to get the closest font to the name requested.
+     *
+     * try fontname
+     * try all aliases for fontname
+     * foreach fallback for fontname
+     *	    try the fallback
+     *	    try all aliases for the fallback
+     */
+
+    nameList = ListFontOrAlias(display, want.fa.family, &numNames);
+    if (numNames == 0) {
+	const char *const *const *fontFallbacks;
+	int i, j;
+	const char *fallback;
+
+	fontFallbacks = TkFontGetFallbacks();
+	for (i = 0; fontFallbacks[i] != NULL; i++) {
+	    for (j = 0; (fallback = fontFallbacks[i][j]) != NULL; j++) {
+		if (strcasecmp(want.fa.family, fallback) == 0) {
+		    break;
+		}
+	    }
+	    if (fallback != NULL) {
+		for (j = 0; (fallback = fontFallbacks[i][j]) != NULL; j++) {
+		    nameList = ListFontOrAlias(display, fallback, &numNames);
+		    if (numNames != 0) {
+			goto found;
+		    }
+		}
+	    }
+	}
+	nameList = ListFonts(display, "fixed", &numNames);
+	if (numNames == 0) {
+	    nameList = ListFonts(display, "*", &numNames);
+	}
+	if (numNames == 0) {
+	    return GetSystemFont(display);
+	}
+    }
+
+  found:
+    bestIdx[0] = -1;
+    bestIdx[1] = -1;
+    bestScore[0] = (unsigned) -1;
+    bestScore[1] = (unsigned) -1;
+    for (nameIdx = 0; nameIdx < numNames; nameIdx++) {
+	FontAttributes got;
+	int scalable;
+	unsigned score;
+
+	if (TkFontParseXLFD(nameList[nameIdx], &got.fa, &got.xa) != TCL_OK) {
+	    continue;
+	}
+	IdentifySymbolEncodings(&got);
+	scalable = (got.fa.size == 0.0);
+	score = RankAttributes(&want, &got);
+	if (score < bestScore[scalable]) {
+	    bestIdx[scalable] = nameIdx;
+	    bestScore[scalable] = score;
+	}
+	if (score == 0) {
+	    break;
+	}
+    }
+
+    fontStructPtr = GetScreenFont(display, &want, nameList, bestIdx,
+	    bestScore);
+    XFreeFontNames(nameList);
+
+    if (fontStructPtr == NULL) {
+	return GetSystemFont(display);
+    }
+    return fontStructPtr;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * InitFont --
+ *
+ *	Helper for TkpGetNativeFont() and TkpGetFontFromAttributes().
+ *	Initializes the memory for a new UnixFont that wraps the
+ *	platform-specific data.
+ *
+ *	The caller is responsible for initializing the fields of the TkFont
+ *	that are used exclusively by the generic TkFont code, and for
+ *	releasing those fields before calling TkpDeleteFont().
+ *
+ * Results:
+ *	Fills the WinFont structure.
+ *
+ * Side effects:
+ *	Memory allocated.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static void
+InitFont(
+    Tk_Window tkwin,		/* For screen where font will be used. */
+    XFontStruct *fontStructPtr,	/* X information about font. */
+    UnixFont *fontPtr)		/* Filled with information constructed from
+				 * the above arguments. */
+{
+    ThreadSpecificData *tsdPtr =
+	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
+    unsigned long value;
+    int minHi, maxHi, minLo, maxLo, fixed, width, limit, i, n;
+    FontAttributes fa;
+    TkFontAttributes *faPtr;
+    TkFontMetrics *fmPtr;
+    SubFont *controlPtr, *subFontPtr;
+    char *pageMap;
+    Display *display;
+
+    /*
+     * Get all font attributes and metrics.
+     */
+
+    display = Tk_Display(tkwin);
+    GetFontAttributes(display, fontStructPtr, &fa);
+
+    minHi = fontStructPtr->min_byte1;
+    maxHi = fontStructPtr->max_byte1;
+    minLo = fontStructPtr->min_char_or_byte2;
+    maxLo = fontStructPtr->max_char_or_byte2;
+
+    fixed = 1;
+    if (fontStructPtr->per_char != NULL) {
+	width = 0;
+	limit = (maxHi - minHi + 1) * (maxLo - minLo + 1);
+	for (i = 0; i < limit; i++) {
+	    n = fontStructPtr->per_char[i].width;
+	    if (n != 0) {
+		if (width == 0) {
+		    width = n;
+		} else if (width != n) {
+		    fixed = 0;
+		    break;
+		}
+	    }
+	}
+    }
+
+    fontPtr->font.fid = fontStructPtr->fid;
+
+    faPtr = &fontPtr->font.fa;
+    faPtr->family = fa.fa.family;
+    faPtr->size = TkFontGetPoints(tkwin, fa.fa.size);
+    faPtr->weight = fa.fa.weight;
+    faPtr->slant = fa.fa.slant;
+    faPtr->underline = 0;
+    faPtr->overstrike = 0;
+
+    fmPtr = &fontPtr->font.fm;
+    fmPtr->ascent = fontStructPtr->ascent;
+    fmPtr->descent = fontStructPtr->descent;
+    fmPtr->maxWidth = fontStructPtr->max_bounds.width;
+    fmPtr->fixed = fixed;
+
+    fontPtr->display = display;
+    fontPtr->pixelSize = (int)(TkFontGetPixels(tkwin, fa.fa.size) + 0.5);
+    fontPtr->xa = fa.xa;
+
+    fontPtr->numSubFonts = 1;
+    fontPtr->subFontArray = fontPtr->staticSubFonts;
+    InitSubFont(display, fontStructPtr, 1, &fontPtr->subFontArray[0]);
+
+    fontPtr->controlSubFont = fontPtr->subFontArray[0];
+    subFontPtr = FindSubFontForChar(fontPtr, '0', NULL);
+    controlPtr = &fontPtr->controlSubFont;
+    controlPtr->fontStructPtr = subFontPtr->fontStructPtr;
+    controlPtr->familyPtr = &tsdPtr->controlFamily;
+    controlPtr->fontMap = tsdPtr->controlFamily.fontMap;
+
+    pageMap = fontPtr->subFontArray[0].fontMap[0];
+    for (i = 0; i < 256; i++) {
+	if ((minHi > 0) || (i < minLo) || (i > maxLo)
+		|| !((pageMap[i>>3] >> (i&7)) & 1)) {
+	    n = 0;
+	} else if (fontStructPtr->per_char == NULL) {
+	    n = fontStructPtr->max_bounds.width;
+	} else {
+	    n = fontStructPtr->per_char[i - minLo].width;
+	}
+	fontPtr->widths[i] = n;
+    }
+
+    if (XGetFontProperty(fontStructPtr, XA_UNDERLINE_POSITION, &value)) {
+	fontPtr->underlinePos = value;
+    } else {
+	/*
+	 * If the XA_UNDERLINE_POSITION property does not exist, the X manual
+	 * recommends using the following value:
+	 */
+
+	fontPtr->underlinePos = fontStructPtr->descent / 2;
+    }
+    fontPtr->barHeight = 0;
+    if (XGetFontProperty(fontStructPtr, XA_UNDERLINE_THICKNESS, &value)) {
+	fontPtr->barHeight = value;
+    }
+    if (fontPtr->barHeight == 0) {
+	/*
+	 * If the XA_UNDERLINE_THICKNESS property does not exist, the X manual
+	 * recommends using the width of the stem on a capital letter. I don't
+	 * know of a way to get the stem width of a letter, so guess and use
+	 * 1/3 the width of a capital I.
+	 */
+
+	fontPtr->barHeight = fontPtr->widths['I'] / 3;
+	if (fontPtr->barHeight == 0) {
+	    fontPtr->barHeight = 1;
+	}
+    }
+    if (fontPtr->underlinePos + fontPtr->barHeight > fontStructPtr->descent) {
+	/*
+	 * If this set of cobbled together values would cause the bottom of
+	 * the underline bar to stick below the descent of the font, jack the
+	 * underline up a bit higher.
+	 */
+
+	fontPtr->barHeight = fontStructPtr->descent - fontPtr->underlinePos;
+	if (fontPtr->barHeight == 0) {
+	    fontPtr->underlinePos--;
+	    fontPtr->barHeight = 1;
+	}
+    }
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * ReleaseFont --
+ *
+ *	Called to release the unix-specific contents of a TkFont. The caller
+ *	is responsible for freeing the memory used by the font itself.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Memory is freed.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static void
+ReleaseFont(
+    UnixFont *fontPtr)		/* The font to delete. */
+{
+    int i;
+
+    for (i = 0; i < fontPtr->numSubFonts; i++) {
+	ReleaseSubFont(fontPtr->display, &fontPtr->subFontArray[i]);
+    }
+    if (fontPtr->subFontArray != fontPtr->staticSubFonts) {
+	ckfree(fontPtr->subFontArray);
+    }
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * InitSubFont --
+ *
+ *	Wrap a screen font and load the FontFamily that represents it. Used to
+ *	prepare a SubFont so that characters can be mapped from UTF-8 to the
+ *	charset of the font.
+ *
+ * Results:
+ *	The subFontPtr is filled with information about the font.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static void
+InitSubFont(
+    Display *display,		/* Display in which font will be used. */
+    XFontStruct *fontStructPtr,	/* The screen font. */
+    int base,			/* Non-zero if this SubFont is being used as
+				 * the base font for a font object. */
+    SubFont *subFontPtr)	/* Filled with SubFont constructed from above
+				 * attributes. */
+{
+    subFontPtr->fontStructPtr = fontStructPtr;
+    subFontPtr->familyPtr = AllocFontFamily(display, fontStructPtr, base);
+    subFontPtr->fontMap = subFontPtr->familyPtr->fontMap;
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * ReleaseSubFont --
+ *
+ *	Called to release the contents of a SubFont. The caller is responsible
+ *	for freeing the memory used by the SubFont itself.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Memory and resources are freed.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static void
+ReleaseSubFont(
+    Display *display,		/* Display which owns screen font. */
+    SubFont *subFontPtr)	/* The SubFont to delete. */
+{
+    XFreeFont(display, subFontPtr->fontStructPtr);
+    FreeFontFamily(subFontPtr->familyPtr);
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * AllocFontFamily --
+ *
+ *	Find the FontFamily structure associated with the given font name.
+ *	The information should be stored by the caller in a SubFont and used
+ *	when determining if that SubFont supports a character.
+ *
+ *	Cannot use the string name used to construct the font as the key,
+ *	because the capitalization may not be canonical. Therefore use the
+ *	face name actually retrieved from the font metrics as the key.
+ *
+ * Results:
+ *	A pointer to a FontFamily. The reference count in the FontFamily is
+ *	automatically incremented. When the SubFont is released, the reference
+ *	count is decremented. When no SubFont is using this FontFamily, it may
+ *	be deleted.
+ *
+ * Side effects:
+ *	A new FontFamily structure will be allocated if this font family has
+ *	not been seen. TrueType character existence metrics are loaded into
+ *	the FontFamily structure.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static FontFamily *
+AllocFontFamily(
+    Display *display,		/* Display in which font will be used. */
+    XFontStruct *fontStructPtr,	/* Screen font whose FontFamily is to be
+				 * returned. */
+    int base)			/* Non-zero if this font family is to be used
+				 * in the base font of a font object. */
+{
+    FontFamily *familyPtr;
+    FontAttributes fa;
+    Tcl_Encoding encoding;
+    ThreadSpecificData *tsdPtr =
+	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
+
+    GetFontAttributes(display, fontStructPtr, &fa);
+    encoding = Tcl_GetEncoding(NULL, GetEncodingAlias(fa.xa.charset));
+
+    familyPtr = tsdPtr->fontFamilyList;
+    for (; familyPtr != NULL; familyPtr = familyPtr->nextPtr) {
+	if ((familyPtr->faceName == fa.fa.family)
+		&& (familyPtr->foundry == fa.xa.foundry)
+		&& (familyPtr->encoding == encoding)) {
+	    if (encoding) {
+		Tcl_FreeEncoding(encoding);
+	    }
+	    familyPtr->refCount++;
+	    return familyPtr;
+	}
+    }
+
+    familyPtr = ckalloc(sizeof(FontFamily));
+    memset(familyPtr, 0, sizeof(FontFamily));
+    familyPtr->nextPtr = tsdPtr->fontFamilyList;
+    tsdPtr->fontFamilyList = familyPtr;
+
+    /*
+     * Set key for this FontFamily.
+     */
+
+    familyPtr->foundry = fa.xa.foundry;
+    familyPtr->faceName = fa.fa.family;
+    familyPtr->encoding = encoding;
+
+    /*
+     * An initial refCount of 2 means that FontFamily information will persist
+     * even when the SubFont that loaded the FontFamily is released. Change it
+     * to 1 to cause FontFamilies to be unloaded when not in use.
+     */
+
+    familyPtr->refCount = 2;
+
+    /*
+     * One byte/character fonts have both min_byte1 and max_byte1 0, and
+     * max_char_or_byte2 <= 255. Anything else specifies a two byte/character
+     * font.
+     */
+
+    familyPtr->isTwoByteFont = !(
+	    (fontStructPtr->min_byte1 == 0) &&
+	    (fontStructPtr->max_byte1 == 0) &&
+	    (fontStructPtr->max_char_or_byte2 < 256));
+    return familyPtr;
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * FreeFontFamily --
+ *
+ *	Called to free an FontFamily when the SubFont is finished using it.
+ *	Frees the contents of the FontFamily and the memory used by the
+ *	FontFamily itself.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static void
+FreeFontFamily(
+    FontFamily *familyPtr)	/* The FontFamily to delete. */
+{
+    FontFamily **familyPtrPtr;
+    ThreadSpecificData *tsdPtr =
+	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
+    int i;
+
+    if (familyPtr == NULL) {
+	return;
+    }
+    familyPtr->refCount--;
+    if (familyPtr->refCount > 0) {
+	return;
+    }
+    if (familyPtr->encoding) {
+	Tcl_FreeEncoding(familyPtr->encoding);
+    }
+    for (i = 0; i < FONTMAP_PAGES; i++) {
+	if (familyPtr->fontMap[i] != NULL) {
+	    ckfree(familyPtr->fontMap[i]);
+	}
+    }
+
+    /*
+     * Delete from list.
+     */
+
+    for (familyPtrPtr = &tsdPtr->fontFamilyList; ; ) {
+	if (*familyPtrPtr == familyPtr) {
+	    *familyPtrPtr = familyPtr->nextPtr;
+	    break;
+	}
+	familyPtrPtr = &(*familyPtrPtr)->nextPtr;
+    }
+
+    ckfree(familyPtr);
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * FindSubFontForChar --
+ *
+ *	Determine which screen font is necessary to use to display the given
+ *	character. If the font object does not have a screen font that can
+ *	display the character, another screen font may be loaded into the font
+ *	object, following a set of preferred fallback rules.
+ *
+ * Results:
+ *	The return value is the SubFont to use to display the given character.
+ *
+ * Side effects:
+ *	The contents of fontPtr are modified to cache the results of the
+ *	lookup and remember any SubFonts that were dynamically loaded. The
+ *	table of SubFonts might be extended, and if a non-NULL reference to a
+ *	subfont pointer is available, it is updated if it previously pointed
+ *	into the old subfont table.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static SubFont *
+FindSubFontForChar(
+    UnixFont *fontPtr,		/* The font object with which the character
+				 * will be displayed. */
+    int ch,			/* The Unicode character to be displayed. */
+    SubFont **fixSubFontPtrPtr)	/* Subfont reference to fix up if we
+				 * reallocate our subfont table. */
+{
+    int i, j, k, numNames;
+    Tk_Uid faceName;
+    const char *fallback;
+    const char *const *aliases;
+    char **nameList;
+    const char *const *anyFallbacks;
+    const char *const *const *fontFallbacks;
+    SubFont *subFontPtr;
+    Tcl_DString ds;
+
+    if (FontMapLookup(&fontPtr->subFontArray[0], ch)) {
+	return &fontPtr->subFontArray[0];
+    }
+
+    for (i = 1; i < fontPtr->numSubFonts; i++) {
+	if (FontMapLookup(&fontPtr->subFontArray[i], ch)) {
+	    return &fontPtr->subFontArray[i];
+	}
+    }
+
+    if (FontMapLookup(&fontPtr->controlSubFont, ch)) {
+	return &fontPtr->controlSubFont;
+    }
+
+    /*
+     * Keep track of all face names that we check, so we don't check some name
+     * multiple times if it can be reached by multiple paths.
+     */
+
+    Tcl_DStringInit(&ds);
+
+    /*
+     * Are there any other fonts with the same face name as the base font that
+     * could display this character, e.g., if the base font is
+     * adobe:fixed:iso8859-1, we could might be able to use
+     * misc:fixed:iso8859-8 or sony:fixed:jisx0208.1983-0
+     */
+
+    faceName = fontPtr->font.fa.family;
+    if (SeenName(faceName, &ds) == 0) {
+	subFontPtr = CanUseFallback(fontPtr, faceName, ch, fixSubFontPtrPtr);
+	if (subFontPtr != NULL) {
+	    goto end;
+	}
+    }
+
+    aliases = TkFontGetAliasList(faceName);
+
+    subFontPtr = NULL;
+    fontFallbacks = TkFontGetFallbacks();
+    for (i = 0; fontFallbacks[i] != NULL; i++) {
+	for (j = 0; (fallback = fontFallbacks[i][j]) != NULL; j++) {
+	    if (strcasecmp(fallback, faceName) == 0) {
+		/*
+		 * If the base font has a fallback...
+		 */
+
+		goto tryfallbacks;
+	    } else if (aliases != NULL) {
+		/*
+		 * Or if an alias for the base font has a fallback...
+		 */
+
+		for (k = 0; aliases[k] != NULL; k++) {
+		    if (strcasecmp(fallback, aliases[k]) == 0) {
+			goto tryfallbacks;
+		    }
+		}
+	    }
+	}
+	continue;
+
+    tryfallbacks:
+
+	/*
+	 * ...then see if we can use one of the fallbacks, or an alias for one
+	 * of the fallbacks.
+	 */
+
+	for (j = 0; (fallback = fontFallbacks[i][j]) != NULL; j++) {
+	    subFontPtr = CanUseFallbackWithAliases(fontPtr, fallback, ch, &ds,
+		    fixSubFontPtrPtr);
+	    if (subFontPtr != NULL) {
+		goto end;
+	    }
+	}
+    }
+
+    /*
+     * See if we can use something from the global fallback list.
+     */
+
+    anyFallbacks = TkFontGetGlobalClass();
+    for (i = 0; (fallback = anyFallbacks[i]) != NULL; i++) {
+	subFontPtr = CanUseFallbackWithAliases(fontPtr, fallback, ch, &ds,
+		fixSubFontPtrPtr);
+	if (subFontPtr != NULL) {
+	    goto end;
+	}
+    }
+
+    /*
+     * Try all face names available in the whole system until we find one that
+     * can be used.
+     */
+
+    nameList = ListFonts(fontPtr->display, "*", &numNames);
+    for (i = 0; i < numNames; i++) {
+	fallback = strchr(nameList[i] + 1, '-') + 1;
+	strchr(fallback, '-')[0] = '\0';
+	if (SeenName(fallback, &ds) == 0) {
+	    subFontPtr = CanUseFallback(fontPtr, fallback, ch,
+		    fixSubFontPtrPtr);
+	    if (subFontPtr != NULL) {
+		XFreeFontNames(nameList);
+		goto end;
+	    }
+	}
+    }
+    XFreeFontNames(nameList);
+
+  end:
+    Tcl_DStringFree(&ds);
+
+    if (subFontPtr == NULL) {
+	/*
+	 * No font can display this character, so it will be displayed as a
+	 * control character expansion.
+	 */
+
+	subFontPtr = &fontPtr->controlSubFont;
+	FontMapInsert(subFontPtr, ch);
+    }
+    return subFontPtr;
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * FontMapLookup --
+ *
+ *	See if the screen font can display the given character.
+ *
+ * Results:
+ *	The return value is 0 if the screen font cannot display the character,
+ *	non-zero otherwise.
+ *
+ * Side effects:
+ *	New pages are added to the font mapping cache whenever the character
+ *	belongs to a page that hasn't been seen before. When a page is loaded,
+ *	information about all the characters on that page is stored, not just
+ *	for the single character in question.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static int
+FontMapLookup(
+    SubFont *subFontPtr,	/* Contains font mapping cache to be queried
+				 * and possibly updated. */
+    int ch)			/* Character to be tested. */
+{
+    int row, bitOffset;
+
+    row = ch >> FONTMAP_SHIFT;
+    if (subFontPtr->fontMap[row] == NULL) {
+	FontMapLoadPage(subFontPtr, row);
+    }
+    bitOffset = ch & (FONTMAP_BITSPERPAGE - 1);
+    return (subFontPtr->fontMap[row][bitOffset >> 3] >> (bitOffset & 7)) & 1;
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * FontMapInsert --
+ *
+ *	Tell the font mapping cache that the given screen font should be used
+ *	to display the specified character. This is called when no font on the
+ *	system can be be found that can display that character; we lie to the
+ *	font and tell it that it can display the character, otherwise we would
+ *	end up re-searching the entire fallback hierarchy every time that
+ *	character was seen.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	New pages are added to the font mapping cache whenever the character
+ *	belongs to a page that hasn't been seen before. When a page is loaded,
+ *	information about all the characters on that page is stored, not just
+ *	for the single character in question.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static void
+FontMapInsert(
+    SubFont *subFontPtr,	/* Contains font mapping cache to be
+				 * updated. */
+    int ch)			/* Character to be added to cache. */
+{
+    int row, bitOffset;
+
+    row = ch >> FONTMAP_SHIFT;
+    if (subFontPtr->fontMap[row] == NULL) {
+	FontMapLoadPage(subFontPtr, row);
+    }
+    bitOffset = ch & (FONTMAP_BITSPERPAGE - 1);
+    subFontPtr->fontMap[row][bitOffset >> 3] |= 1 << (bitOffset & 7);
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * FontMapLoadPage --
+ *
+ *	Load information about all the characters on a given page. This
+ *	information consists of one bit per character that indicates whether
+ *	the associated screen font can (1) or cannot (0) display the
+ *	characters on the page.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Memory allocated.
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+FontMapLoadPage(
+    SubFont *subFontPtr,	/* Contains font mapping cache to be
+				 * updated. */
+    int row)			/* Index of the page to be loaded into the
+				 * cache. */
+{
+    char buf[16], src[6];
+    int minHi, maxHi, minLo, maxLo, scale, checkLo;
+    int i, end, bitOffset, isTwoByteFont, n;
+    Tcl_Encoding encoding;
+    XFontStruct *fontStructPtr;
+    XCharStruct *widths;
+    ThreadSpecificData *tsdPtr =
+	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
+
+    subFontPtr->fontMap[row] = ckalloc(FONTMAP_BITSPERPAGE / 8);
+    memset(subFontPtr->fontMap[row], 0, FONTMAP_BITSPERPAGE / 8);
+
+    if (subFontPtr->familyPtr == &tsdPtr->controlFamily) {
+	return;
+    }
+
+    fontStructPtr = subFontPtr->fontStructPtr;
+    encoding = subFontPtr->familyPtr->encoding;
+    isTwoByteFont = subFontPtr->familyPtr->isTwoByteFont;
+
+    widths = fontStructPtr->per_char;
+    minHi = fontStructPtr->min_byte1;
+    maxHi = fontStructPtr->max_byte1;
+    minLo = fontStructPtr->min_char_or_byte2;
+    maxLo = fontStructPtr->max_char_or_byte2;
+    scale = maxLo - minLo + 1;
+    checkLo = minLo;
+
+    if (! isTwoByteFont) {
+	if (minLo < 32) {
+	    checkLo = 32;
+	}
+    }
+
+    end = (row + 1) << FONTMAP_SHIFT;
+    for (i = row << FONTMAP_SHIFT; i < end; i++) {
+	int hi, lo;
+
+	if (Tcl_UtfToExternal(NULL, encoding, src, TkUniCharToUtf(i, src),
+		TCL_ENCODING_STOPONERROR, NULL, buf, sizeof(buf), NULL,
+		NULL, NULL) != TCL_OK) {
+	    continue;
+	}
+	if (isTwoByteFont) {
+	    hi = ((unsigned char *) buf)[0];
+	    lo = ((unsigned char *) buf)[1];
+	} else {
+	    hi = 0;
+	    lo = ((unsigned char *) buf)[0];
+	}
+	if ((hi < minHi) || (hi > maxHi) || (lo < checkLo) || (lo > maxLo)) {
+	    continue;
+	}
+	n = (hi - minHi) * scale + lo - minLo;
+	if ((widths == NULL) || (widths[n].width + widths[n].rbearing != 0)) {
+	    bitOffset = i & (FONTMAP_BITSPERPAGE - 1);
+	    subFontPtr->fontMap[row][bitOffset >> 3] |= 1 << (bitOffset & 7);
+	}
+    }
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * CanUseFallbackWithAliases --
+ *
+ *	Helper function for FindSubFontForChar. Determine if the specified
+ *	face name (or an alias of the specified face name) can be used to
+ *	construct a screen font that can display the given character.
+ *
+ * Results:
+ *	See CanUseFallback().
+ *
+ * Side effects:
+ *	If the name and/or one of its aliases was rejected, the rejected
+ *	string is recorded in nameTriedPtr so that it won't be tried again.
+ *	The table of SubFonts might be extended, and if a non-NULL reference
+ *	to a subfont pointer is available, it is updated if it previously
+ *	pointed into the old subfont table.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static SubFont *
+CanUseFallbackWithAliases(
+    UnixFont *fontPtr,		/* The font object that will own the new
+				 * screen font. */
+    const char *faceName,		/* Desired face name for new screen font. */
+    int ch,			/* The Unicode character that the new screen
+				 * font must be able to display. */
+    Tcl_DString *nameTriedPtr,	/* Records face names that have already been
+				 * tried. It is possible for the same face
+				 * name to be queried multiple times when
+				 * trying to find a suitable screen font. */
+    SubFont **fixSubFontPtrPtr)	/* Subfont reference to fix up if we
+				 * reallocate our subfont table. */
+{
+    SubFont *subFontPtr;
+    const char *const *aliases;
+    int i;
+
+    if (SeenName(faceName, nameTriedPtr) == 0) {
+	subFontPtr = CanUseFallback(fontPtr, faceName, ch, fixSubFontPtrPtr);
+	if (subFontPtr != NULL) {
+	    return subFontPtr;
+	}
+    }
+    aliases = TkFontGetAliasList(faceName);
+    if (aliases != NULL) {
+	for (i = 0; aliases[i] != NULL; i++) {
+	    if (SeenName(aliases[i], nameTriedPtr) == 0) {
+		subFontPtr = CanUseFallback(fontPtr, aliases[i], ch,
+			fixSubFontPtrPtr);
+		if (subFontPtr != NULL) {
+		    return subFontPtr;
+		}
+	    }
+	}
+    }
+    return NULL;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * SeenName --
+ *
+ *	Used to determine we have already tried and rejected the given face
+ *	name when looking for a screen font that can support some Unicode
+ *	character.
+ *
+ * Results:
+ *	The return value is 0 if this face name has not already been seen,
+ *	non-zero otherwise.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static int
+SeenName(
+    const char *name,		/* The name to check. */
+    Tcl_DString *dsPtr)		/* Contains names that have already been
+				 * seen. */
+{
+    const char *seen, *end;
+
+    seen = Tcl_DStringValue(dsPtr);
+    end = seen + Tcl_DStringLength(dsPtr);
+    while (seen < end) {
+	if (strcasecmp(seen, name) == 0) {
+	    return 1;
+	}
+	seen += strlen(seen) + 1;
+    }
+    Tcl_DStringAppend(dsPtr, name, (int) (strlen(name) + 1));
+    return 0;
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * CanUseFallback --
+ *
+ *	If the specified screen font has not already been loaded into the font
+ *	object, determine if the specified screen font can display the given
+ *	character.
+ *
+ * Results:
+ *	The return value is a pointer to a newly allocated SubFont, owned by
+ *	the font object. This SubFont can be used to display the given
+ *	character. The SubFont represents the screen font with the base set of
+ *	font attributes from the font object, but using the specified face
+ *	name. NULL is returned if the font object already holds a reference to
+ *	the specified font or if the specified font doesn't exist or cannot
+ *	display the given character.
+ *
+ * Side effects:
+ *	The font object's subFontArray is updated to contain a reference to
+ *	the newly allocated SubFont. The table of SubFonts might be extended,
+ *	and if a non-NULL reference to a subfont pointer is available, it is
+ *	updated if it previously pointed into the old subfont table.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+static SubFont *
+CanUseFallback(
+    UnixFont *fontPtr,		/* The font object that will own the new
+				 * screen font. */
+    const char *faceName,	/* Desired face name for new screen font. */
+    int ch,			/* The Unicode character that the new screen
+				 * font must be able to display. */
+    SubFont **fixSubFontPtrPtr)	/* Subfont reference to fix up if we
+				 * reallocate our subfont table. */
+{
+    int i, nameIdx, numNames, srcLen, numEncodings, bestIdx[2];
+    Tk_Uid hateFoundry;
+    const char *charset, *hateCharset;
+    unsigned bestScore[2];
+    char **nameList;
+    char **nameListOrig;
+    char src[6];
+    FontAttributes want, got;
+    Display *display;
+    SubFont subFont;
+    XFontStruct *fontStructPtr;
+    Tcl_DString dsEncodings;
+    Tcl_Encoding *encodingCachePtr;
+
+    /*
+     * Assume: the face name is times.
+     * Assume: adobe:times:iso8859-1 has already been used.
+     *
+     * Are there any versions of times that can display this character (e.g.,
+     *    perhaps linotype:times:iso8859-2)?
+     *	  a. Get list of all times fonts.
+     *	  b1. Cross out all names whose encodings we've already used.
+     *	  b2. Cross out all names whose foundry & encoding we've already seen.
+     *	  c. Cross out all names whose encoding cannot handle the character.
+     *	  d. Rank each name and pick the best match.
+     *	  e. If that font cannot actually display the character, cross out all
+     *	     names with the same foundry and encoding and go back to (c).
+     */
+
+    display = fontPtr->display;
+    nameList = ListFonts(display, faceName, &numNames);
+    if (numNames == 0) {
+	return NULL;
+    }
+    nameListOrig = nameList;
+
+    srcLen = TkUniCharToUtf(ch, src);
+
+    want.fa = fontPtr->font.fa;
+    want.xa = fontPtr->xa;
+
+    want.fa.family = Tk_GetUid(faceName);
+    want.fa.size = (double)-fontPtr->pixelSize;
+
+    hateFoundry = NULL;
+    hateCharset = NULL;
+    numEncodings = 0;
+    Tcl_DStringInit(&dsEncodings);
+
+    charset = NULL;	/* lint, since numNames must be > 0 to get here. */
+
+  retry:
+    bestIdx[0] = -1;
+    bestIdx[1] = -1;
+    bestScore[0] = (unsigned) -1;
+    bestScore[1] = (unsigned) -1;
+    for (nameIdx = 0; nameIdx < numNames; nameIdx++) {
+	Tcl_Encoding encoding;
+	char dst[16];
+	int scalable, srcRead, dstWrote;
+	unsigned score;
+
+	if (nameList[nameIdx] == NULL) {
+	    continue;
+	}
+	if (TkFontParseXLFD(nameList[nameIdx], &got.fa, &got.xa) != TCL_OK) {
+	    goto crossout;
+	}
+	IdentifySymbolEncodings(&got);
+	charset = GetEncodingAlias(got.xa.charset);
+	if (hateFoundry != NULL) {
+	    /*
+	     * E. If the font we picked cannot actually display the character,
+	     * cross out all names with the same foundry and encoding.
+	     */
+
+	    if ((hateFoundry == got.xa.foundry)
+		    && (strcmp(hateCharset, charset) == 0)) {
+		goto crossout;
+	    }
+	} else {
+	    /*
+	     * B. Cross out all names whose encodings we've already used.
+	     */
+
+	    for (i = 0; i < fontPtr->numSubFonts; i++) {
+		encoding = fontPtr->subFontArray[i].familyPtr->encoding;
+		if (strcmp(charset, Tcl_GetEncodingName(encoding)) == 0) {
+		    goto crossout;
+		}
+	    }
+	}
+
+	/*
+	 * C. Cross out all names whose encoding cannot handle the character.
+	 */
+
+	encodingCachePtr = (Tcl_Encoding *) Tcl_DStringValue(&dsEncodings);
+	for (i = numEncodings; --i >= 0; encodingCachePtr++) {
+	    encoding = *encodingCachePtr;
+	    if (strcmp(Tcl_GetEncodingName(encoding), charset) == 0) {
+		break;
+	    }
+	}
+	if (i < 0) {
+	    encoding = Tcl_GetEncoding(NULL, charset);
+	    if (encoding == NULL) {
+		goto crossout;
+	    }
+
+	    Tcl_DStringAppend(&dsEncodings, (char *) &encoding,
+		    sizeof(encoding));
+	    numEncodings++;
+	}
+	Tcl_UtfToExternal(NULL, encoding, src, srcLen,
+		TCL_ENCODING_STOPONERROR, NULL, dst, sizeof(dst), &srcRead,
+		&dstWrote, NULL);
+	if (dstWrote == 0) {
+	    goto crossout;
+	}
+
+	/*
+	 * D. Rank each name and pick the best match.
+	 */
+
+	scalable = (got.fa.size == 0.0);
+	score = RankAttributes(&want, &got);
+	if (score < bestScore[scalable]) {
+	    bestIdx[scalable] = nameIdx;
+	    bestScore[scalable] = score;
+	}
+	if (score == 0) {
+	    break;
+	}
+	continue;
+
+    crossout:
+	if (nameList == nameListOrig) {
+	    /*
+	     * Not allowed to change pointers to memory that X gives you, so
+	     * make a copy.
+	     */
+
+	    nameList = ckalloc(numNames * sizeof(char *));
+	    memcpy(nameList, nameListOrig, numNames * sizeof(char *));
+	}
+	nameList[nameIdx] = NULL;
+    }
+
+    fontStructPtr = GetScreenFont(display, &want, nameList, bestIdx,
+	    bestScore);
+
+    encodingCachePtr = (Tcl_Encoding *) Tcl_DStringValue(&dsEncodings);
+    for (i = numEncodings; --i >= 0; encodingCachePtr++) {
+	Tcl_FreeEncoding(*encodingCachePtr);
+    }
+    Tcl_DStringFree(&dsEncodings);
+    numEncodings = 0;
+
+    if (fontStructPtr == NULL) {
+	if (nameList != nameListOrig) {
+	    ckfree(nameList);
+	}
+	XFreeFontNames(nameListOrig);
+	return NULL;
+    }
+
+    InitSubFont(display, fontStructPtr, 0, &subFont);
+    if (FontMapLookup(&subFont, ch) == 0) {
+	/*
+	 * E. If the font we picked cannot actually display the character,
+	 * cross out all names with the same foundry and encoding and pick
+	 * another font.
+	 */
+
+	hateFoundry = got.xa.foundry;
+	hateCharset = charset;
+	ReleaseSubFont(display, &subFont);
+	goto retry;
+    }
+    if (nameList != nameListOrig) {
+	ckfree(nameList);
+    }
+    XFreeFontNames(nameListOrig);
+
+    if (fontPtr->numSubFonts >= SUBFONT_SPACE) {
+	SubFont *newPtr;
+
+	newPtr = ckalloc(sizeof(SubFont) * (fontPtr->numSubFonts + 1));
+	memcpy(newPtr, fontPtr->subFontArray,
+		fontPtr->numSubFonts * sizeof(SubFont));
+	if (fixSubFontPtrPtr != NULL) {
+	    register SubFont *fixSubFontPtr = *fixSubFontPtrPtr;
+
+	    if (fixSubFontPtr != &fontPtr->controlSubFont) {
+		*fixSubFontPtrPtr =
+			newPtr + (fixSubFontPtr - fontPtr->subFontArray);
+	    }
+	}
+	if (fontPtr->subFontArray != fontPtr->staticSubFonts) {
+	    ckfree(fontPtr->subFontArray);
+	}
+	fontPtr->subFontArray = newPtr;
+    }
+    fontPtr->subFontArray[fontPtr->numSubFonts] = subFont;
+    fontPtr->numSubFonts++;
+    return &fontPtr->subFontArray[fontPtr->numSubFonts - 1];
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * RankAttributes --
+ *
+ *	Determine how close the attributes of the font in question match the
+ *	attributes that we want.
+ *
+ * Results:
+ *	The return value is the score; lower numbers are better. *scalablePtr
+ *	is set to 0 if the font was not scalable, 1 otherwise.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static unsigned
+RankAttributes(
+    FontAttributes *wantPtr,	/* The desired attributes. */
+    FontAttributes *gotPtr)	/* The attributes we have to live with. */
+{
+    unsigned penalty;
+
+    penalty = 0;
+    if (gotPtr->xa.foundry != wantPtr->xa.foundry) {
+	penalty += 4500;
+    }
+    if (gotPtr->fa.family != wantPtr->fa.family) {
+	penalty += 9000;
+    }
+    if (gotPtr->fa.weight != wantPtr->fa.weight) {
+	penalty += 90;
+    }
+    if (gotPtr->fa.slant != wantPtr->fa.slant) {
+	penalty += 60;
+    }
+    if (gotPtr->xa.slant != wantPtr->xa.slant) {
+	penalty += 10;
+    }
+    if (gotPtr->xa.setwidth != wantPtr->xa.setwidth) {
+	penalty += 1000;
+    }
+
+    if (gotPtr->fa.size == 0.0) {
+	/*
+	 * A scalable font is almost always acceptable, but the corresponding
+	 * bitmapped font would be better.
+	 */
+
+	penalty += 10;
+    } else {
+	int diff;
+
+	/*
+	 * It's worse to be too large than to be too small.
+	 */
+
+	diff = (int) (150 * (-gotPtr->fa.size - -wantPtr->fa.size));
+	if (diff > 0) {
+	    penalty += 600;
+	} else if (diff < 0) {
+	    penalty += 150;
+	    diff = -diff;
+	}
+	penalty += diff;
+    }
+    if (gotPtr->xa.charset != wantPtr->xa.charset) {
+	int i;
+	const char *gotAlias, *wantAlias;
+
+	penalty += 65000;
+	gotAlias = GetEncodingAlias(gotPtr->xa.charset);
+	wantAlias = GetEncodingAlias(wantPtr->xa.charset);
+	if (strcmp(gotAlias, wantAlias) != 0) {
+	    penalty += 30000;
+	    for (i = 0; encodingList[i] != NULL; i++) {
+		if (strcmp(gotAlias, encodingList[i]) == 0) {
+		    penalty -= 30000;
+		    break;
+		}
+		penalty += 20000;
+	    }
+	}
+    }
+    return penalty;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * GetScreenFont --
+ *
+ *	Given the names for the best scalable and best bitmapped font,
+ *	actually construct an XFontStruct based on the best XLFD. This is
+ *	where all the alias and fallback substitution bottoms out.
+ *
+ * Results:
+ *	The screen font that best corresponds to the set of attributes.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static XFontStruct *
+GetScreenFont(
+    Display *display,		/* Display for new XFontStruct. */
+    FontAttributes *wantPtr,	/* Contains desired actual pixel-size if the
+				 * best font was scalable. */
+    char **nameList,		/* Array of XLFDs. */
+    int bestIdx[2],		/* Indices into above array for XLFD of best
+				 * bitmapped and best scalable font. */
+    unsigned bestScore[2])	/* Scores of best bitmapped and best scalable
+				 * font. XLFD corresponding to lowest score
+				 * will be constructed. */
+{
+    XFontStruct *fontStructPtr;
+
+    if ((bestIdx[0] < 0) && (bestIdx[1] < 0)) {
+	return NULL;
+    }
+
+    /*
+     * Now we know which is the closest matching scalable font and the closest
+     * matching bitmapped font. If the scalable font was a better match, try
+     * getting the scalable font; however, if the scalable font was not
+     * actually available in the desired pointsize, fall back to the closest
+     * bitmapped font.
+     */
+
+    fontStructPtr = NULL;
+    if (bestScore[1] < bestScore[0]) {
+	char *str, *rest, buf[256];
+	int i;
+
+	/*
+	 * Fill in the desired pixel size for this font.
+	 */
+
+    tryscale:
+	str = nameList[bestIdx[1]];
+	for (i = 0; i < XLFD_PIXEL_SIZE; i++) {
+	    str = strchr(str + 1, '-');
+	}
+	rest = str;
+	for (i = XLFD_PIXEL_SIZE; i < XLFD_CHARSET; i++) {
+	    rest = strchr(rest + 1, '-');
+	}
+	*str = '\0';
+	sprintf(buf, "%.200s-%d-*-*-*-*-*%s", nameList[bestIdx[1]],
+		(int)(-wantPtr->fa.size+0.5), rest);
+	*str = '-';
+	fontStructPtr = XLoadQueryFont(display, buf);
+	bestScore[1] = INT_MAX;
+    }
+    if (fontStructPtr == NULL) {
+	fontStructPtr = XLoadQueryFont(display, nameList[bestIdx[0]]);
+	if (fontStructPtr == NULL) {
+	    /*
+	     * This shouldn't happen because the font name is one of the names
+	     * that X gave us to use, but it does anyhow.
+	     */
+
+	    if (bestScore[1] < INT_MAX) {
+		goto tryscale;
+	    }
+	    return GetSystemFont(display);
+	}
+    }
+    return fontStructPtr;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * GetSystemFont --
+ *
+ *	Absolute fallback mechanism, called when we need a font and no other
+ *	font can be found and/or instantiated.
+ *
+ * Results:
+ *	A pointer to a font. Never NULL.
+ *
+ * Side effects:
+ *	If there are NO fonts installed on the system, this call will panic,
+ *	but how did you get X running in that case?
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static XFontStruct *
+GetSystemFont(
+    Display *display)		/* Display for new XFontStruct. */
+{
+    XFontStruct *fontStructPtr;
+
+    fontStructPtr = XLoadQueryFont(display, "fixed");
+    if (fontStructPtr == NULL) {
+	fontStructPtr = XLoadQueryFont(display, "*");
+	if (fontStructPtr == NULL) {
+	    Tcl_Panic("TkpGetFontFromAttributes: cannot get any font");
+	}
+    }
+    return fontStructPtr;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * GetFontAttributes --
+ *
+ *	Given a screen font, determine its actual attributes, which are not
+ *	necessarily the attributes that were used to construct it.
+ *
+ * Results:
+ *	*faPtr is filled with the screen font's attributes.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static int
+GetFontAttributes(
+    Display *display,		/* Display that owns the screen font. */
+    XFontStruct *fontStructPtr,	/* Screen font to query. */
+    FontAttributes *faPtr)	/* For storing attributes of screen font. */
+{
+    unsigned long value;
+    char *name;
+
+    if ((XGetFontProperty(fontStructPtr, XA_FONT, &value) != False) &&
+	    (value != 0)) {
+	name = XGetAtomName(display, (Atom) value);
+	if (TkFontParseXLFD(name, &faPtr->fa, &faPtr->xa) != TCL_OK) {
+	    faPtr->fa.family = Tk_GetUid(name);
+	    faPtr->xa.foundry = Tk_GetUid("");
+	    faPtr->xa.charset = Tk_GetUid("");
+	}
+	XFree(name);
+    } else {
+	TkInitFontAttributes(&faPtr->fa);
+	TkInitXLFDAttributes(&faPtr->xa);
+    }
+
+    /*
+     * Do last ditch check for family. It seems that some X servers can fail
+     * on the X font calls above, slipping through earlier checks. X-Win32 5.4
+     * is one of these.
+     */
+
+    if (faPtr->fa.family == NULL) {
+	faPtr->fa.family = Tk_GetUid("");
+	faPtr->xa.foundry = Tk_GetUid("");
+	faPtr->xa.charset = Tk_GetUid("");
+    }
+    return IdentifySymbolEncodings(faPtr);
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * ListFonts --
+ *
+ *	Utility function to return the array of all XLFDs on the system with
+ *	the specified face name.
+ *
+ * Results:
+ *	The return value is an array of XLFDs, which should be freed with
+ *	XFreeFontNames(), or NULL if no XLFDs matched the requested name.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static char **
+ListFonts(
+    Display *display,		/* Display to query. */
+    const char *faceName,	/* Desired face name, or "*" for all. */
+    int *numNamesPtr)		/* Filled with length of returned array, or 0
+				 * if no names were found. */
+{
+    char buf[256];
+
+    sprintf(buf, "-*-%.80s-*-*-*-*-*-*-*-*-*-*-*-*", faceName);
+    return XListFonts(display, buf, 10000, numNamesPtr);
+}
+
+static char **
+ListFontOrAlias(
+    Display *display,		/* Display to query. */
+    const char *faceName,	/* Desired face name, or "*" for all. */
+    int *numNamesPtr)		/* Filled with length of returned array, or 0
+				 * if no names were found. */
+{
+    char **nameList;
+    const char *const *aliases;
+    int i;
+
+    nameList = ListFonts(display, faceName, numNamesPtr);
+    if (nameList != NULL) {
+	return nameList;
+    }
+    aliases = TkFontGetAliasList(faceName);
+    if (aliases != NULL) {
+	for (i = 0; aliases[i] != NULL; i++) {
+	    nameList = ListFonts(display, aliases[i], numNamesPtr);
+	    if (nameList != NULL) {
+		return nameList;
+	    }
+	}
+    }
+    *numNamesPtr = 0;
+    return NULL;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * IdentifySymbolEncodings --
+ *
+ *	If the font attributes refer to a symbol font, update the charset
+ *	field of the font attributes so that it reflects the encoding of that
+ *	symbol font. In general, the raw value for the charset field parsed
+ *	from an XLFD is meaningless for symbol fonts.
+ *
+ *	Symbol fonts are all fonts whose name appears in the symbolClass.
+ *
+ * Results:
+ *	The return value is non-zero if the font attributes specify a symbol
+ *	font, or 0 otherwise. If a non-zero value is returned the charset
+ *	field of the font attributes will be changed to the string that
+ *	represents the actual encoding for the symbol font.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static int
+IdentifySymbolEncodings(
+    FontAttributes *faPtr)
+{
+    int i, j;
+    const char *const *aliases;
+    const char *const *symbolClass;
+
+    symbolClass = TkFontGetSymbolClass();
+    for (i = 0; symbolClass[i] != NULL; i++) {
+	if (strcasecmp(faPtr->fa.family, symbolClass[i]) == 0) {
+	    faPtr->xa.charset = Tk_GetUid(GetEncodingAlias(symbolClass[i]));
+	    return 1;
+	}
+	aliases = TkFontGetAliasList(symbolClass[i]);
+	for (j = 0; (aliases != NULL) && (aliases[j] != NULL); j++) {
+	    if (strcasecmp(faPtr->fa.family, aliases[j]) == 0) {
+		faPtr->xa.charset = Tk_GetUid(GetEncodingAlias(aliases[j]));
+		return 1;
+	    }
+	}
+    }
+    return 0;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * GetEncodingAlias --
+ *
+ *	Map the name of an encoding to another name that should be used when
+ *	actually loading the encoding. For instance, the encodings
+ *	"jisc6226.1978", "jisx0208.1983", "jisx0208.1990", and "jisx0208.1996"
+ *	are well-known names for the same encoding and are represented by one
+ *	encoding table: "jis0208".
+ *
+ * Results:
+ *	As above. If the name has no alias, the original name is returned.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static const char *
+GetEncodingAlias(
+    const char *name)		/* The name to look up. */
+{
+    EncodingAlias *aliasPtr;
+
+    for (aliasPtr = encodingAliases; aliasPtr->aliasPattern != NULL; ) {
+	if (Tcl_StringMatch(name, aliasPtr->aliasPattern)) {
+	    return aliasPtr->realName;
+	}
+	aliasPtr++;
+    }
+    return name;
+}
+
+/*
+ *---------------------------------------------------------------------------
+ *
+ * TkDrawAngledChars --
+ *
+ *	Draw some characters at an angle. This is awkward here because we have
+ *	no reliable way of drawing any characters at an angle in classic X11;
+ *	we have to draw on a Pixmap which is converted to an XImage (from
+ *	helper function GetImageOfText), rotate the image (hokey code!) onto
+ *	another XImage (from helper function InitDestImage), and then use the
+ *	rotated image as a mask when drawing. This is pretty awful; improved
+ *	versions are welcomed!
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Target drawable is updated.
+ *
+ *---------------------------------------------------------------------------
+ */
+
+static inline XImage *
+GetImageOfText(
+    Display *display,		/* Display on which to draw. */
+    Drawable drawable,		/* Window or pixmap in which to draw. */
+    Tk_Font tkfont,		/* Font in which characters will be drawn. */
+    const char *source,		/* UTF-8 string to be displayed. Need not be
+				 * '\0' terminated. All Tk meta-characters
+				 * (tabs, control characters, and newlines)
+				 * should be stripped out of the string that
+				 * is passed to this function. If they are not
+				 * stripped out, they will be displayed as
+				 * regular printing characters. */
+    int numBytes,		/* Number of bytes in string. */
+    int *realWidthPtr, int *realHeightPtr)
+{
+    int width, height;
+    TkFont *fontPtr = (TkFont *) tkfont;
+    Pixmap bitmap;
+    GC bitmapGC;
+    XGCValues values;
+    XImage *image;
+
+    (void) Tk_MeasureChars(tkfont, source, numBytes, -1, 0, &width);
+    height = fontPtr->fm.ascent + fontPtr->fm.descent;
+
+    bitmap = Tk_GetPixmap(display, drawable, width, height, 1);
+    values.graphics_exposures = False;
+    values.foreground = BlackPixel(display, DefaultScreen(display));
+    bitmapGC = XCreateGC(display, bitmap, GCGraphicsExposures|GCForeground,
+	    &values);
+    XFillRectangle(display, bitmap, bitmapGC, 0, 0, width, height);
+
+    values.font = Tk_FontId(tkfont);
+    values.foreground = WhitePixel(display, DefaultScreen(display));
+    values.background = BlackPixel(display, DefaultScreen(display));
+    XChangeGC(display, bitmapGC, GCFont|GCForeground|GCBackground, &values);
+    Tk_DrawChars(display, bitmap, bitmapGC, tkfont, source, numBytes, 0,
+	    fontPtr->fm.ascent);
+    XFreeGC(display, bitmapGC);
+
+    image = XGetImage(display, bitmap, 0, 0, width, height, AllPlanes,
+	    ZPixmap);
+    Tk_FreePixmap(display, bitmap);
+
+    *realWidthPtr = width;
+    *realHeightPtr = height;
+    return image;
+}
+
+static inline XImage *
+InitDestImage(
+    Display *display,
+    Drawable drawable,
+    int width,
+    int height,
+    Pixmap *bitmapPtr)
+{
+    Pixmap bitmap;
+    XImage *image;
+    GC bitmapGC;
+    XGCValues values;
+
+    bitmap = Tk_GetPixmap(display, drawable, width, height, 1);
+    values.graphics_exposures = False;
+    values.foreground = BlackPixel(display, DefaultScreen(display));
+    bitmapGC = XCreateGC(display, bitmap, GCGraphicsExposures|GCForeground,
+	    &values);
+    XFillRectangle(display, bitmap, bitmapGC, 0, 0, width, height);
+    XFreeGC(display, bitmapGC);
+
+    image = XGetImage(display, bitmap, 0, 0, width, height, AllPlanes,
+	    ZPixmap);
+    *bitmapPtr = bitmap;
+    return image;
+}
+
+void
+TkDrawAngledChars(
+    Display *display,		/* Display on which to draw. */
+    Drawable drawable,		/* Window or pixmap in which to draw. */
+    GC gc,			/* Graphics context for drawing characters. */
+    Tk_Font tkfont,		/* Font in which characters will be drawn;
+				 * must be the same as font used in GC. */
+    const char *source,		/* UTF-8 string to be displayed. Need not be
+				 * '\0' terminated. All Tk meta-characters
+				 * (tabs, control characters, and newlines)
+				 * should be stripped out of the string that
+				 * is passed to this function. If they are not
+				 * stripped out, they will be displayed as
+				 * regular printing characters. */
+    int numBytes,		/* Number of bytes in string. */
+    double x, double y,
+    double angle)
+{
+    if (angle == 0.0) {
+	Tk_DrawChars(display, drawable, gc, tkfont, source, numBytes, x, y);
+    } else {
+	double sinA = sin(angle * PI/180.0), cosA = cos(angle * PI/180.0);
+	int bufHeight, bufWidth, srcWidth, srcHeight, i, j, dx, dy;
+	Pixmap buf;
+	XImage *srcImage = GetImageOfText(display, drawable, tkfont, source,
+		numBytes, &srcWidth, &srcHeight);
+	XImage *dstImage;
+	enum {Q0=1,R1,Q1,R2,Q2,R3,Q3} quadrant;
+	GC bwgc, cpgc;
+	XGCValues values;
+	int ascent = ((TkFont *) tkfont)->fm.ascent;
+
+	/*
+	 * First, work out what quadrant we are operating in. We also handle
+	 * the rectilinear rotations as special cases. Conceptually, there's
+	 * also R0 (angle == 0.0) but that has been already handled as a
+	 * special case above.
+	 *
+	 *        R1
+	 *   Q1   |   Q0
+	 *        |
+	 * R2 ----+---- R0
+	 *        |
+	 *   Q2   |   Q3
+	 *        R3
+	 */
+
+	if (angle < 90.0) {
+	    quadrant = Q0;
+	} else if (angle == 90.0) {
+	    quadrant = R1;
+	} else if (angle < 180.0) {
+	    quadrant = Q1;
+	} else if (angle == 180.0) {
+	    quadrant = R2;
+	} else if (angle < 270.0) {
+	    quadrant = Q2;
+	} else if (angle == 270.0) {
+	    quadrant = R3;
+	} else {
+	    quadrant = Q3;
+	}
+
+	if (srcImage == NULL) {
+	    return;
+	}
+	bufWidth = srcWidth*fabs(cosA) + srcHeight*fabs(sinA);
+	bufHeight = srcHeight*fabs(cosA) + srcWidth*fabs(sinA);
+	dstImage = InitDestImage(display, drawable, bufWidth,bufHeight, &buf);
+	if (dstImage == NULL) {
+	    Tk_FreePixmap(display, buf);
+	    XDestroyImage(srcImage);
+	    return;
+	}
+
+	/*
+	 * Do the rotation, setting or resetting pixels in the destination
+	 * image dependent on whether the corresponding pixel (after rotation
+	 * to source image space) is set.
+	 */
+
+	for (i=0 ; i<srcWidth ; i++) {
+	    for (j=0 ; j<srcHeight ; j++) {
+		switch (quadrant) {
+		case Q0:
+		    dx = ROUND16(i*cosA + j*sinA);
+		    dy = ROUND16(j*cosA + (srcWidth - i)*sinA);
+		    break;
+		case R1:
+		    dx = j;
+		    dy = srcWidth - i;
+		    break;
+		case Q1:
+		    dx = ROUND16((i - srcWidth)*cosA + j*sinA);
+		    dy = ROUND16((srcWidth-i)*sinA + (j-srcHeight)*cosA);
+		    break;
+		case R2:
+		    dx = srcWidth - i;
+		    dy = srcHeight - j;
+		    break;
+		case Q2:
+		    dx = ROUND16((i-srcWidth)*cosA + (j-srcHeight)*sinA);
+		    dy = ROUND16((j - srcHeight)*cosA - i*sinA);
+		    break;
+		case R3:
+		    dx = srcHeight - j;
+		    dy = i;
+		    break;
+		default:
+		    dx = ROUND16(i*cosA + (j - srcHeight)*sinA);
+		    dy = ROUND16(j*cosA - i*sinA);
+		}
+
+		if (dx < 0 || dy < 0 || dx >= bufWidth || dy >= bufHeight) {
+		    continue;
+		}
+		XPutPixel(dstImage, dx, dy,
+			XGetPixel(dstImage,dx,dy) | XGetPixel(srcImage,i,j));
+	    }
+	}
+	XDestroyImage(srcImage);
+
+	/*
+	 * Schlep the data back to the Xserver.
+	 */
+
+	values.function = GXcopy;
+	values.foreground = WhitePixel(display, DefaultScreen(display));
+	values.background = BlackPixel(display, DefaultScreen(display));
+	bwgc = XCreateGC(display, buf, GCFunction|GCForeground|GCBackground,
+		&values);
+	XPutImage(display, buf, bwgc, dstImage, 0,0, 0,0, bufWidth,bufHeight);
+	XFreeGC(display, bwgc);
+	XDestroyImage(dstImage);
+
+	/*
+	 * Calculate where we want to draw the text.
+	 */
+
+	switch (quadrant) {
+	case Q0:
+	    dx = x;
+	    dy = y - srcWidth*sinA;
+	    break;
+	case R1:
+	    dx = x;
+	    dy = y - srcWidth;
+	    break;
+	case Q1:
+	    dx = x + srcWidth*cosA;
+	    dy = y + srcHeight*cosA - srcWidth*sinA;
+	    break;
+	case R2:
+	    dx = x - srcWidth;
+	    dy = y - srcHeight;
+	    break;
+	case Q2:
+	    dx = x + srcWidth*cosA + srcHeight*sinA;
+	    dy = y + srcHeight*cosA;
+	    break;
+	case R3:
+	    dx = x - srcHeight;
+	    dy = y;
+	    break;
+	default:
+	    dx = x + srcHeight*sinA;
+	    dy = y;
+	}
+
+	/*
+	 * Apply a correction to deal with the fact that we aren't told to
+	 * draw from our top-left corner but rather from the left-end of our
+	 * baseline.
+	 */
+
+	dx -= ascent*sinA;
+	dy -= ascent*cosA;
+
+	/*
+	 * Transfer the text to the screen. This is done by using it as a mask
+	 * and then drawing through that mask with the original drawing color.
+	 */
+
+	values.function = GXcopy;
+	values.fill_style = FillSolid;
+	values.clip_mask = buf;
+	values.clip_x_origin = dx;
+	values.clip_y_origin = dy;
+	cpgc = XCreateGC(display, drawable,
+		GCFunction|GCFillStyle|GCClipMask|GCClipXOrigin|GCClipYOrigin,
+		&values);
+	XCopyGC(display, gc, GCForeground, cpgc);
+	XFillRectangle(display, drawable, cpgc, dx, dy, bufWidth,
+		bufHeight);
+	XFreeGC(display, cpgc);
+
+	Tk_FreePixmap(display, buf);
+	return;
+    }
+}
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */