The Annoyance Filter.pdf - Fourmilab

§139 ANNOYANCE-FILTER MAIL FOLDER 123
}
〈 Reset MIME decoder state 142 〉;
}
else {
newMessage = false ;
}
This code is cited in section 256.
This code is used in section 130.
140. To facilitate message parsing, we delete any white space from the ends of lines. Mail transfer
agents are explicitly permitted to do this, and all forms of encoding are proof against it. If the line is
blank after pruning trailing white space, we note this to use in testing for the start of the next message
for non-BSD folders.
〈 Eliminate any trailing space from line 140 〉 ≡
while ((s.length ( ) > 0) ∧ (isISOspace (s[s.length ( ) − 1]))) {
s.erase (s.length ( ) − 1);
}
setNewMessageEligiblity (s.empty ( ));
This code is used in section 130.
141. If we’re within the message header section, there are various things we want to be on the lookout
for. First, of course, is the blank line that denotes the end of the header. If the header declares the
content type of the body to be MIME multi-part, we need to save the part boundary separator for later
use. As it happens, this code works equally fine for parsing the part headers which follow the sentinel
denoting the start of new part in a MIME multi-part message.
〈 Process message header lines 141 〉 ≡
if (inHeader ∨ inPartHeader ) {
if (s ≡ "") {
if (inHeader ) {
if ((¬multiPart ) ∧ (bodyContentTransferEncoding ≠ "")) {
mimeContentType = bodyContentType ;
mimeContentTypeCharset = bodyContentTypeCharset ;
mimeContentTypeName = bodyContentTypeName ;
mimeContentTransferEncoding = bodyContentTransferEncoding ;
multiPart = true ;
partBoundary = "";
}
}
inHeader = inPartHeader = false ;
〈 Activate MIME decoder if required 153 〉;
}
〈 Check for continuation of mail header lines 143 〉;
〈 Save Message-ID for diagnostics 145 〉;
〈 Process multipart MIME header declaration 150 〉;
〈 Process body content type declarations 146 〉;
〈 Check for encoded header line and decode 147 〉;
}
This code is used in section 130.