The Annoyance Filter.pdf - Fourmilab

§177 ANNOYANCE-FILTER TOKEN PARSER 151
177. To avoid accidentally blundering into HTML comment discarding in non-HTML text, we look
for start and end HTML tags and only activate HTML comment detection inside something which is
plausibly HTML. Note that unclosed HTML tags and comments are automatically closed out when
reset is called at the start of a new message from the mail folder.
〈 Check for within HTML content 177 〉 ≡
if (cl [clp] ≡ ’’ ∨ cl [clp + 5] ≡ ’␣’)) {
string tag ;
for (int i = 1; i < 5; i++) {
tag += (islower (cl [clp + i])) ? toupper (cl [clp + i]) : cl [clp + i];
}
if (tag ≡ "HTML") {
inHTML = true ;
#ifdef HTML_COMMENT_DEBUG
cout ≪ "−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−␣In␣HTML:␣" ≪ cl ≪ endl ;
#endif
}
}
}
if (cl [clp] ≡ ’’)) {
string tag ;
for (int i = 2; i < 6; i++) {
tag += (islower (cl [clp + i])) ? toupper (cl [clp + i]) : cl [clp + i];
}
if (tag ≡ "HTML") {
inHTML = false ;
#ifdef HTML_COMMENT_DEBUG
cout ≪ "−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−␣Out␣of␣HTML:␣" ≪ cl ≪ endl ;
#endif
}
}
}
This code is used in section 174.