src/expat/xmlwf/xmlmime.c

   1 #include <string.h>
   2 #include "xmlmime.h"
   3
   4 static const char *
   5 getTok(const char **pp)
   6 {
   7   /* inComment means one level of nesting; inComment+1 means two levels etc */
   8   enum { inAtom, inString, init, inComment };
   9   int state = init;
  10   const char *tokStart = 0;
  11   for (;;) {
  12     switch (**pp) {
  13     case '\0':
  14       if (state == inAtom)
  15         return tokStart;
  16       return 0;
  17     case ' ':
  18     case '\r':
  19     case '\t':
  20     case '\n':
  21       if (state == inAtom)
  22         return tokStart;
  23       break;
  24     case '(':
  25       if (state == inAtom)
  26         return tokStart;
  27       if (state != inString)
  28         state++;
  29       break;
  30     case ')':
  31       if (state > init)
  32         --state;
  33       else if (state != inString)
  34         return 0;
  35       break;
  36     case ';':
  37     case '/':
  38     case '=':
  39       if (state == inAtom)
  40         return tokStart;
  41       if (state == init)
  42         return (*pp)++;
  43       break;
  44     case '\\':
  45       ++*pp;
  46       if (**pp == '\0')
  47         return 0;
  48       break;
  49     case '"':
  50       switch (state) {
  51       case inString:
  52         ++*pp;
  53         return tokStart;
  54       case inAtom:
  55         return tokStart;
  56       case init:
  57         tokStart = *pp;
  58         state = inString;
  59         break;
  60       }
  61       break;
  62     default:
  63       if (state == init) {
  64         tokStart = *pp;
  65         state = inAtom;
  66       }
  67       break;
  68     }
  69     ++*pp;
  70   }
  71   /* not reached */
  72 }
  73
  74 /* key must be lowercase ASCII */
  75
  76 static int
  77 matchkey(const char *start, const char *end, const char *key)
  78 {
  79   if (!start)
  80     return 0;
  81   for (; start != end; start++, key++)
  82     if (*start != *key && *start != 'A' + (*key - 'a'))
  83       return 0;
  84   return *key == '\0';
  85 }
  86
  87 void
  88 getXMLCharset(const char *buf, char *charset)
  89 {
  90   const char *next, *p;
  91
  92   charset[0] = '\0';
  93   next = buf;
  94   p = getTok(&next);
  95   if (matchkey(p, next, "text"))
  96     strcpy(charset, "us-ascii");
  97   else if (!matchkey(p, next, "application"))
  98     return;
  99   p = getTok(&next);
 100   if (!p || *p != '/')
 101     return;
 102   p = getTok(&next);
 103 #if 0
 104   if (!matchkey(p, next, "xml") && charset[0] == '\0')
 105     return;
 106 #endif
 107   p = getTok(&next);
 108   while (p) {
 109     if (*p == ';') {
 110       p = getTok(&next);
 111       if (matchkey(p, next, "charset")) {
 112         p = getTok(&next);
 113         if (p && *p == '=') {
 114           p = getTok(&next);
 115           if (p) {
 116             char *s = charset;
 117             if (*p == '"') {
 118               while (++p != next - 1) {
 119                 if (*p == '\\')
 120                   ++p;
 121                 if (s == charset + CHARSET_MAX - 1) {
 122                   charset[0] = '\0';
 123                   break;
 124                 }
 125                 *s++ = *p;
 126               }
 127               *s++ = '\0';
 128             }
 129             else {
 130               if (next - p > CHARSET_MAX - 1)
 131                 break;
 132               while (p != next)
 133                 *s++ = *p++;
 134               *s = 0;
 135               break;
 136             }
 137           }
 138         }
 139         break;
 140       }
 141     }
 142   else
 143     p = getTok(&next);
 144   }
 145 }
 146
 147 #ifdef TEST
 148
 149 #include <stdio.h>
 150
 151 int
 152 main(int argc, char *argv[])
 153 {
 154   char buf[CHARSET_MAX];
 155   if (argc <= 1)
 156     return 1;
 157   printf("%s\n", argv[1]);
 158   getXMLCharset(argv[1], buf);
 159   printf("charset=\"%s\"\n", buf);
 160   return 0;
 161 }
 162
 163 #endif /* TEST */