note 97230 modified in function.quoted-printable-encode by danbrown
| From: | danbrown@php.net | Date: | Fri, 09 Apr 2010 13:11:25 +0000 |
| Subject: | note 97230 modified in function.quoted-printable-encode by danbrown | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-168076@lists.php.net to get a copy of this message | ||
A function that QP-encodes an input string (written for PHP < 5.3) and
wordwraps it at the same time, in order to avoid classification according to the MIME QP LONG LINE
rule of SpamAssassin. Thanks for Matt Jeffers to point out errors in the below quoted_printable
script!
<?php
function quoted_printable_encode($input, $line_max = 75) {
$hex =
array('0','1','2','3','4','5','6','7',
'8','9','A','B','C','D','E','F');
$lines = preg_split("/(?:\r\n|\r|\n)/", $input);
$linebreak = "=0D=0A=\r\n";
/* the linebreak also counts as characters in the mime_qp_long_line
* rule of spam-assassin */
$line_max = $line_max - strlen($linebreak);
$escape = "=";
$output = "";
$cur_conv_line = "";
$length = 0;
$whitespace_pos = 0;
$addtl_chars = 0;
// iterate lines
for ($j=0; $j<count($lines); $j++) {
$line = $lines[$j];
$linlen = strlen($line);
// iterate chars
for ($i = 0; $i < $linlen; $i++) {
$c = substr($line, $i, 1);
$dec = ord($c);
$length++;
if ($dec == 32) {
// space occurring at end of line, need to encode
if (($i == ($linlen - 1))) {
$c = "=20";
$length += 2;
}
$addtl_chars = 0;
$whitespace_pos = $i;
} elseif ( ($dec == 61) || ($dec < 32 ) || ($dec > 126) ) {
$h2 = floor($dec/16); $h1 = floor($dec%16);
$c = $escape . $hex["$h2"] . $hex["$h1"];
$length += 2;
$addtl_chars += 2;
}
// length for wordwrap exceeded, get a newline into the text
if ($length >= $line_max) {
$cur_conv_line .= $c;
// read only up to the whitespace for the current line
$whitesp_diff = $i - $whitespace_pos + $addtl_chars;
/* the text after the whitespace will have to be read
* again ( + any additional characters that came into
* existence as a result of the encoding process after the whitespace)
*
* Also, do not start at 0, if there was *no* whitespace in
* the whole line */
if (($i + $addtl_chars) > $whitesp_diff) {
$output .= substr($cur_conv_line, 0, (strlen($cur_conv_line) -
$whitesp_diff)) . $linebreak;
$i = $i - $whitesp_diff + $addtl_chars;
} else {
$output .= $cur_conv_line . $linebreak;
}
$cur_conv_line = "";
$length = 0;
$whitespace_pos = 0;
} else {
// length for wordwrap not reached, continue reading
$cur_conv_line .= $c;
}
} // end of for
$length = 0;
$whitespace_pos = 0;
$output .= $cur_conv_line;
$cur_conv_line = "";
if ($j<=count($lines)-1) {
$output .= $linebreak;
}
} // end for
return trim($output);
} // end quoted_printable_encode
?>
--was--
Thanks for Matt Jeffers to point out errors in the below quoted_printable script! The new version
should be working as expected:
<?php
function quoted_printable_encode($input, $line_max = 75) {
$hex =
array('0','1','2','3','4','5','6','7',
'8','9','A','B','C','D','E','F');
$lines = preg_split("/(?:\r\n|\r|\n)/", $input);
$linebreak = "=0D=0A=\r\n";
/* the linebreak also counts as characters in the mime_qp_long_line
* rule of spam-assassin */
$line_max = $line_max - strlen($linebreak);
$escape = "=";
$output = "";
$cur_conv_line = "";
$length = 0;
$whitespace_pos = 0;
$addtl_chars = 0;
// iterate lines
for ($j=0; $j<count($lines); $j++) {
$line = $lines[$j];
$linlen = strlen($line);
// iterate chars
for ($i = 0; $i < $linlen; $i++) {
$c = substr($line, $i, 1);
$dec = ord($c);
$length++;
if ($dec == 32) {
// space occurring at end of line, need to encode
if (($i == ($linlen - 1))) {
$c = "=20";
$length += 2;
}
$addtl_chars = 0;
$whitespace_pos = $i;
} elseif ( ($dec == 61) || ($dec < 32 ) || ($dec > 126) ) {
$h2 = floor($dec/16); $h1 = floor($dec%16);
$c = $escape . $hex["$h2"] . $hex["$h1"];
$length += 2;
$addtl_chars += 2;
}
// length for wordwrap exceeded, get a newline into the text
if ($length >= $line_max) {
$cur_conv_line .= $c;
// read only up to the whitespace for the current line
$whitesp_diff = $i - $whitespace_pos + $addtl_chars;
/* the text after the whitespace will have to be read
* again ( + any additional characters that came into
* existence as a result of the encoding process after the whitespace)
*
* Also, do not start at 0, if there was *no* whitespace in
* the whole line */
if (($i + $addtl_chars) > $whitesp_diff) {
$output .= substr($cur_conv_line, 0, (strlen($cur_conv_line) -
$whitesp_diff)) . $linebreak;
$i = $i - $whitesp_diff + $addtl_chars;
} else {
$output .= $cur_conv_line . $linebreak;
}
$cur_conv_line = "";
$length = 0;
$whitespace_pos = 0;
} else {
// length for wordwrap not reached, continue reading
$cur_conv_line .= $c;
}
} // end of for
$length = 0;
$whitespace_pos = 0;
$output .= $cur_conv_line;
$cur_conv_line = "";
if ($j<=count($lines)-1) {
$output .= $linebreak;
}
} // end for
return trim($output);
} // end quoted_printable_encode
?>
http://php.net/manual/en/function.quoted-printable-encode.php