src/expat/xmlwf/ct.c

#define CHARSET_MAX 41

static const char *
getTok(const char **pp)
{
  enum { inAtom, inString, init, inComment };
  int state = init;
  const char *tokStart = 0;
  for (;;) {
    switch (**pp) {
    case '\0':
      return 0;
    case ' ':
    case '\r':
    case '\t':
    case '\n':
      if (state == inAtom)
        return tokStart;
      break;
    case '(':
      if (state == inAtom)
        return tokStart;
      if (state != inString)
        state++;
      break;
    case ')':
      if (state > init)
        --state;
      else if (state != inString)
        return 0;
      break;
    case ';':
    case '/':
    case '=':
      if (state == inAtom)
        return tokStart;
      if (state == init)
        return (*pp)++;
      break;
    case '\\':
      ++*pp;
      if (**pp == '\0')
        return 0;
      break;
    case '"':
      switch (state) {
      case inString:
        ++*pp;
        return tokStart;
      case inAtom:
        return tokStart;
      case init:
        tokStart = *pp;
        state = inString;
        break;
      }
      break;
    default:
      if (state == init) {
        tokStart = *pp;
        state = inAtom;
      }
      break;
    }
    ++*pp;
  }
  /* not reached */
}

/* key must be lowercase ASCII */

static int
matchkey(const char *start, const char *end, const char *key)
{
  if (!start)
    return 0;
  for (; start != end; start++, key++)
    if (*start != *key && *start != 'A' + (*key - 'a'))
      return 0;
  return *key == '\0';
}

void
getXMLCharset(const char *buf, char *charset)
{
  const char *next, *p;

  charset[0] = '\0';
  next = buf;
  p = getTok(&next);
  if (matchkey(p, next, "text"))
    strcpy(charset, "us-ascii");
  else if (!matchkey(p, next, "application"))
    return;
  p = getTok(&next);
  if (!p || *p != '/')
    return;
  p = getTok(&next);
  if (matchkey(p, next, "xml"))
    isXml = 1;
  p = getTok(&next);
  while (p) {
    if (*p == ';') {
      p = getTok(&next);
      if (matchkey(p, next, "charset")) {
        p = getTok(&next);
        if (p && *p == '=') {
          p = getTok(&next);
          if (p) {
            char *s = charset;
            if (*p == '"') {
              while (++p != next - 1) {
                if (*p == '\\')
                  ++p;
                if (s == charset + CHARSET_MAX - 1) {
                  charset[0] = '\0';
                  break;
                }
                *s++ = *p;
              }
              *s++ = '\0';
            }
            else {
              if (next - p > CHARSET_MAX - 1)
                break;
              while (p != next)
                *s++ = *p++;
              *s = 0;
              break;
            }
          }
        }
      }
    }
  else
    p = getTok(&next);
  }
}

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