<?php
// Function that checks whether the data are the on-screen text.
// It works in the following way:
// an array arrfailAt stores the control words for the current state of the stack, which show that
// input data are something else than plain text.
// For example, there may be a description of font or color palette etc.
function rtf_isPlainText($s) {
$arrfailAt = array("*", "fonttbl", "colortbl", "datastore", "themedata");
for ($i = 0; $i < count($arrfailAt); $i++)
if (!empty($s[$arrfailAt[$i]])) return false;
return true;
}
function rtf2text($filename) {
// Read the data from the input file.
$text = file_get_contents($filename);
if (!strlen($text))
return "";
// Create empty stack array.
$document = "";
$stack = array();
$j = -1;
// Read the data character-by- character…
for ($i = 0, $len = strlen($text); $i < $len; $i++) {
$c = $text[$i];
// Depending on current character select the further actions.
switch ($c) {
// the most important key word backslash
case "\\":
// read next character
$nc = $text[$i + 1];
// If it is another backslash or nonbreaking space or hyphen,
// then the character is plain text and add it to the output stream.
if ($nc == '\\' && rtf_isPlainText($stack[$j])) $document .= '\\';
elseif ($nc == '~' && rtf_isPlainText($stack[$j])) $document .= ' ';
elseif ($nc == '_' && rtf_isPlainText($stack[$j])) $document .= '-';
// If it is an asterisk mark, add it to the stack.
elseif ($nc == '*') $stack[$j]["*"] = true;
// If it is a single quote, read next two characters that are the hexadecimal notation
// of a character we should add to the output stream.
elseif ($nc == "'") {
$hex = substr($text, $i + 2, 2);
if (rtf_isPlainText($stack[$j]))
$document .= html_entity_decode("&#".hexdec($hex).";");
//Shift the pointer.
$i += 2;
// Since, we’ve found the alphabetic character, the next characters are control word
// and, possibly, some digit parameter.
} elseif ($nc >= 'a' && $nc <= 'z' || $nc >= 'A' && $nc <= 'Z') {
$word = "";
$param = null;
// Start reading characters after the backslash.
for ($k = $i + 1, $m = 0; $k < strlen($text); $k++, $m++) {
$nc = $text[$k];
// If the current character is a letter and there were no digits before it,
// then we’re still reading the control word. If there were digits, we should stop
// since we reach the end of the control word.
if ($nc >= 'a' && $nc <= 'z' || $nc >= 'A' && $nc <= 'Z') {
if (empty($param))
$word .= $nc;
else
break;
// If it is a digit, store the parameter.
} elseif ($nc >= '0' && $nc <= '9')
$param .= $nc;
// Since minus sign may occur only before a digit parameter, check whether
// $param is empty. Otherwise, we reach the end of the control word.
elseif ($nc == '-') {
if (empty($param))
$param .= $nc;
else
break;
} else
break;
}
// Shift the pointer on the number of read characters.
$i += $m - 1;
// Start analyzing what we’ve read. We are interested mostly in control words.
$toText = "";
switch (strtolower($word)) {
// If the control word is "u", then its parameter is the decimal notation of the
// Unicode character that should be added to the output stream.
// We need to check whether the stack contains \ucN control word. If it does,
// we should remove the N characters from the output stream.
case "u":
$toText .= html_entity_decode("&#x".dechex($param).";");
$ucDelta = @$stack[$j]["uc"];
if ($ucDelta > 0)
$i += $ucDelta;
break;
// Select line feeds, spaces and tabs.
case "par": case "page": case "column": case "line": case "lbr":
$toText .= "\n";
break;
case "emspace": case "enspace": case "qmspace":
$toText .= " ";
break;
case "tab": $toText .= "\t"; break;
// Add current date and time instead of corresponding labels.
case "chdate": $toText .= date("m.d.Y"); break;
case "chdpl": $toText .= date("l, j F Y"); break;
case "chdpa": $toText .= date("D, j M Y"); break;
case "chtime": $toText .= date("H:i:s"); break;
// Replace some reserved characters to their html analogs.
case "emdash": $toText .= html_entity_decode("—"); break;
case "endash": $toText .= html_entity_decode("–"); break;
case "bullet": $toText .= html_entity_decode("•"); break;
case "lquote": $toText .= html_entity_decode("‘"); break;
case "rquote": $toText .= html_entity_decode("’"); break;
case "ldblquote": $toText .= html_entity_decode("«"); break;
case "rdblquote": $toText .= html_entity_decode("»"); break;
// Add all other to the control words stack. If a control word
// does not include parameters, set ¶m to true.
default:
$stack[$j][strtolower($word)] = empty($param) ? true : $param;
break;
}
// Add data to the output stream if required.
if (rtf_isPlainText($stack[$j]))
$document .= $toText;
}
$i++;
break;
// If we read the opening brace {, then new subgroup starts and we add
// new array stack element and write the data from previous stack element to it.
case "{":
array_push($stack, $stack[$j++]);
break;
// If we read the closing brace }, then we reach the end of subgroup and should remove
// the last stack element.
case "}":
array_pop($stack);
$j--;
break;
// Skip “trash”.
case '\0': case '\r': case '\f': case '\n': break;
// Add other data to the output stream if required.
default:
if (rtf_isPlainText($stack[$j]))
$document .= $c;
break;
}
}
// Return result.
return $document;
}
?>
