Add some Utf16 support, extract font family and style names from name table

[fontconfig.git] / src / fcstr.c

diff --git a/src/fcstr.c b/src/fcstr.c
index bea05d90af13ea310bc70a34e72e0e7b4405e021..a62cb7b93dc6a92a9e823d4e83439425dc038575 100644 (file)
--- a/src/fcstr.c
+++ b/src/fcstr.c
@@ -1,5 +1,5 @@
 /*
- * $XFree86: xc/lib/fontconfig/src/fcstr.c,v 1.5 2002/05/29 22:07:33 keithp Exp $
+ * $XFree86: xc/lib/fontconfig/src/fcstr.c,v 1.6 2002/07/06 23:47:44 keithp Exp $
  *
  * Copyright © 2000 Keith Packard, member of The XFree86 Project, Inc.
  *
@@ -229,6 +229,103 @@ FcUtf8Len (FcChar8        *string,
     return FcTrue;
 }
 
+int
+FcUcs4ToUtf8 (FcChar32 ucs4,
+             FcChar8   dest[FC_UTF8_MAX_LEN])
+{
+    int        bits;
+    FcChar8 *d = dest;
+    
+    if      (ucs4 <       0x80) {  *d++=  ucs4;                         bits= -6; }
+    else if (ucs4 <      0x800) {  *d++= ((ucs4 >>  6) & 0x1F) | 0xC0;  bits=  0; }
+    else if (ucs4 <    0x10000) {  *d++= ((ucs4 >> 12) & 0x0F) | 0xE0;  bits=  6; }
+    else if (ucs4 <   0x200000) {  *d++= ((ucs4 >> 18) & 0x07) | 0xF0;  bits= 12; }
+    else if (ucs4 <  0x4000000) {  *d++= ((ucs4 >> 24) & 0x03) | 0xF8;  bits= 18; }
+    else if (ucs4 < 0x80000000) {  *d++= ((ucs4 >> 30) & 0x01) | 0xFC;  bits= 24; }
+    else return 0;
+
+    for ( ; bits >= 0; bits-= 6) {
+       *d++= ((ucs4 >> bits) & 0x3F) | 0x80;
+    }
+    return d - dest;
+}
+
+#define GetUtf16(src,endian) \
+    ((FcChar16) ((src)[endian == FcEndianBig ? 0 : 1] << 8) | \
+     (FcChar16) ((src)[endian == FcEndianBig ? 1 : 0]))
+
+int
+FcUtf16ToUcs4 (FcChar8 *src_orig,
+              FcEndian endian,
+              FcChar32 *dst,
+              int      len)    /* in bytes */
+{
+    FcChar8    *src = src_orig;
+    FcChar16   a, b;
+    FcChar32   result;
+
+    if (len < 2)
+       return 0;
+    
+    a = GetUtf16 (src, endian); src += 2; len -= 2;
+    
+    /* 
+     * Check for surrogate 
+     */
+    if ((a & 0xfc00) == 0xd800)
+    {
+       if (len < 2)
+           return 0;
+       b = GetUtf16 (src, endian); src += 2; len -= 2;
+       /*
+        * Check for invalid surrogate sequence
+        */
+       if ((b & 0xfc00) != 0xdc00)
+           return 0;
+       result = ((((FcChar32) a & 0x3ff) << 10) |
+                 ((FcChar32) b & 0x3ff)) | 0x10000;
+    }
+    else
+       result = a;
+    *dst = result;
+    return src - src_orig;
+}
+
+FcBool
+FcUtf16Len (FcChar8    *string,
+           FcEndian    endian,
+           int         len,    /* in bytes */
+           int         *nchar,
+           int         *wchar)
+{
+    int                n;
+    int                clen;
+    FcChar32   c;
+    FcChar32   max;
+    
+    n = 0;
+    max = 0;
+    while (len)
+    {
+       clen = FcUtf16ToUcs4 (string, endian, &c, len);
+       if (clen <= 0)  /* malformed UTF8 string */
+           return FcFalse;
+       if (c > max)
+           max = c;
+       string += clen;
+       len -= clen;
+       n++;
+    }
+    *nchar = n;
+    if (max >= 0x10000)
+       *wchar = 4;
+    else if (max > 0x100)
+       *wchar = 2;
+    else
+       *wchar = 1;
+    return FcTrue;
+}
+
 void
 FcStrBufInit (FcStrBuf *buf, FcChar8 *init, int size)
 {