src/fcformat.c

   1 /*
   2  * Copyright © 2008 Red Hat, Inc.
   3  *
   4  * Red Hat Author(s): Behdad Esfahbod
   5  *
   6  * Permission to use, copy, modify, distribute, and sell this software and its
   7  * documentation for any purpose is hereby granted without fee, provided that
   8  * the above copyright notice appear in all copies and that both that
   9  * copyright notice and this permission notice appear in supporting
  10  * documentation, and that the name of Keith Packard not be used in
  11  * advertising or publicity pertaining to distribution of the software without
  12  * specific, written prior permission.  Keith Packard makes no
  13  * representations about the suitability of this software for any purpose.  It
  14  * is provided "as is" without express or implied warranty.
  15  *
  16  * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  17  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  18  * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  19  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  20  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  21  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  22  * PERFORMANCE OF THIS SOFTWARE.
  23  */
  24
  25 #include "fcint.h"
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <stdarg.h>
  29
  30
  31 static void
  32 message (const char *fmt, ...)
  33 {
  34     va_list     args;
  35     va_start (args, fmt);
  36     fprintf (stderr, "Fontconfig: ");
  37     vfprintf (stderr, fmt, args);
  38     fprintf (stderr, "\n");
  39     va_end (args);
  40 }
  41
  42
  43 static FcChar8 *scratch1;
  44 static FcChar8 *scratch2;
  45 static const FcChar8 *format_orig;
  46
  47 static const FcChar8 *
  48 interpret_percent (FcPattern *pat,
  49                    FcStrBuf *buf,
  50                    const FcChar8 *format)
  51 {
  52     switch (*format) {
  53     case '{':
  54     {
  55         FcChar8 *p;
  56         FcPatternElt *e;
  57
  58         format++; /* skip over '{' */
  59
  60         p = (FcChar8 *) strpbrk ((const char *) format, "}");
  61         if (!p)
  62         {
  63             message ("Pattern format missing closing brace");
  64             return format;
  65         }
  66         /* extract the element name */
  67         memcpy (scratch1, format, p - format);
  68         scratch1[p - format] = '\0';
  69
  70         e = FcPatternObjectFindElt (pat, FcObjectFromName ((const char *) scratch1));
  71         if (e)
  72         {
  73             FcValueListPtr l;
  74             l = FcPatternEltValues(e);
  75             FcNameUnparseValueList (buf, l, '\0');
  76         }
  77
  78         p++; /* skip over '}' */
  79         return p;
  80     }
  81     default:
  82         message ("Pattern format has invalid character after '%%' at %d",
  83                  format - format_orig);
  84         return format;
  85     }
  86 }
  87
  88 static char escaped_char(const char ch)
  89 {
  90     switch (ch) {
  91     case 'a':   return '\a';
  92     case 'b':   return '\b';
  93     case 'f':   return '\f';
  94     case 'n':   return '\n';
  95     case 'r':   return '\r';
  96     case 't':   return '\t';
  97     case 'v':   return '\v';
  98     default:    return ch;
  99     }
 100 }
 101
 102 static const FcChar8 *
 103 interpret (FcPattern *pat,
 104            FcStrBuf *buf,
 105            const FcChar8 *format,
 106            FcChar8 term)
 107 {
 108     const FcChar8 *end;
 109
 110     for (end = format; *end && *end != term;)
 111     {
 112         switch (*end)
 113         {
 114         case '\\':
 115             end++; /* skip over '\\' */
 116             FcStrBufChar (buf, escaped_char (*end++));
 117             continue;
 118         case '%':
 119             end++; /* skip over '%' */
 120             if (*end == '%')
 121                 break;
 122             end = interpret_percent (pat, buf, end);
 123             continue;
 124         }
 125         FcStrBufChar (buf, *end);
 126         end++;
 127     }
 128     if (*end != term)
 129         message ("Pattern format ended while looking for '%c'", term);
 130
 131     return end;
 132 }
 133
 134 FcChar8 *
 135 FcPatternFormat (FcPattern *pat, const FcChar8 *format)
 136 {
 137     int len;
 138     FcStrBuf buf;
 139
 140     FcStrBufInit (&buf, 0, 0);
 141     len = strlen ((const char *) format);
 142     scratch1 = malloc (len);
 143     scratch2 = malloc (len);
 144     format_orig = format;
 145
 146     interpret (pat, &buf, format, '\0');
 147
 148     free (scratch1);
 149     free (scratch2);
 150     return FcStrBufDone (&buf);
 151 }
 152
 153 #define __fcformat__
 154 #include "fcaliastail.h"
 155 #undef __fcformat__