unsigned char *
parse_header(unsigned char *head, unsigned char *item, unsigned char **ptr)
{
unsigned char *pos = head;
if (!pos) return NULL;
while (*pos) {
unsigned char *end, *itempos, *value;
int len;
/* Go for a newline. */
while (*pos && *pos != ASCII_LF) pos++;
if (!*pos) break;
pos++; /* Start of line now. */
/* Does item match header line ? */
for (itempos = item; *itempos && *pos; itempos++, pos++)
if (c_toupper(*itempos) != c_toupper(*pos))
break;
if (!*pos) break; /* Nothing left to parse. */
if (*itempos) continue; /* Do not match. */
/* Be tolerant: we accept headers with
* weird syntax, since most browsers does it
* anyway, ie:
* name value
* name :value
* name = value
* name[TAB]:[TAB]value */
end = pos;
/* Skip leading whitespaces if any. */
while (LWS(*pos)) pos++;
if (!*pos) break; /* Nothing left to parse. */
/* Eat ':' or '=' if any. */
if (*pos == ':' || *pos == '=') pos++;
if (!*pos) break; /* Nothing left to parse. */
/* Skip whitespaces after separator if any. */
while (LWS(*pos)) pos++;
if (!*pos) break; /* Nothing left to parse. */
if (pos == end) continue; /* Not an exact match (substring). */
/* Find the end of line/string.
* We fail on control chars and DEL char. */
end = pos;
while (*end != ASCII_DEL && (*end > ' ' || LWS(*end))) end++;
if (!*end) break; /* No end of line, nothing left to parse. */
/* Ignore line if we encountered an unexpected char. */
if (*end != ASCII_CR && *end != ASCII_LF) continue;
/* Strip trailing whitespaces. */
while (end > pos && LWS(end[-1])) end--;
len = end - pos;
assert(len >= 0);
if_assert_failed break;
if (!len) continue; /* Empty value. */
value = memacpy(pos, len);
if (!value) break; /* Allocation failure, stop here. */
if (ptr) *ptr = pos;
return value;
}
return NULL;
}
/* Extract the value of name part of the value of attribute content.
* Ie. @name = "charset" and @str = "text/html; charset=iso-8859-1"
* will store in *@ret an allocated string containing "iso-8859-1".
* It supposes that separator is ';' and ignore first element in the
* list. (ie. '1' is ignored in "1; URL=xxx")
* The return value is one of:
*
* - HEADER_PARAM_FOUND: the parameter was found, copied, and stored in *@ret.
* - HEADER_PARAM_NOT_FOUND: the parameter is not there. *@ret is now NULL.
* - HEADER_PARAM_OUT_OF_MEMORY: error. *@ret is now NULL.
*
* If @ret is NULL, then this function doesn't actually access *@ret,
* and cannot fail with HEADER_PARAM_OUT_OF_MEMORY. Some callers may
* rely on this. */
enum parse_header_param
parse_header_param(unsigned char *str, unsigned char *name, unsigned char **ret)
{
unsigned char *p = str;
int namelen, plen = 0;
if (ret) *ret = NULL; /* default in case of early return */
assert(str && name && *name);
if_assert_failed return HEADER_PARAM_NOT_FOUND;
/* Returns now if string @str is empty. */
if (!*p) return HEADER_PARAM_NOT_FOUND;
namelen = strlen((const char *)name);
do {
p = (unsigned char *)strchr((char *)p, ';');
if (!p) return HEADER_PARAM_NOT_FOUND;
while (*p && (*p == ';' || *p <= ' ')) p++;
if (strlen((const char *)p) < namelen) return HEADER_PARAM_NOT_FOUND;
} while (c_strncasecmp((const char *)p, (const char *)name, namelen));
p += namelen;
while (*p && (*p <= ' ' || *p == '=')) p++;
if (!*p) {
if (ret) {
*ret = stracpy((const unsigned char *)"");
if (!*ret)
return HEADER_PARAM_OUT_OF_MEMORY;
}
return HEADER_PARAM_FOUND;
}
while ((p[plen] > ' ' || LWS(p[plen])) && p[plen] != ';') plen++;
/* Trim ending spaces */
while (plen > 0 && LWS(p[plen - 1])) plen--;
/* XXX: Drop enclosing single quotes if there's some.
*
* Some websites like newsnow.co.uk are using single quotes around url
* in URL field in meta tag content attribute like this:
* <meta http-equiv="Refresh" content="0; URL='http://www.site.com/path/xxx.htm'">
*
* This is an attempt to handle that, but it may break something else.
* We drop all pair of enclosing quotes found (eg. '''url''' => url).
* Please report any issue related to this. --Zas */
while (plen > 1 && *p == '\'' && p[plen - 1] == '\'') {
p++;
plen -= 2;
}
if (ret) {
*ret = memacpy(p, plen);
if (!*ret)
return HEADER_PARAM_OUT_OF_MEMORY;
}
return HEADER_PARAM_FOUND;
}
