filename = $filename; $this->f = @fopen($this->filename, 'rb'); if (!$this->f) { $this->error(sprintf('Cannot open %s !', $filename)); } $this->getPDFVersion(); $this->c = new pdf_context($this->f); // Read xref-Data $this->xref = array(); $this->pdf_read_xref($this->xref, $this->pdf_find_xref()); // Check for Encryption $this->getEncryption(); // Read root $this->pdf_read_root(); } /** * Close the opened file */ public function closeFile() { if (isset($this->f) && is_resource($this->f)) { fclose($this->f); unset($this->f); } } /** * Print Error and die * * @param string $msg Error-Message */ public function error($msg) { die('PDF-Parser Error: '.$msg); } /** * Check Trailer for Encryption */ public function getEncryption() { if (isset($this->xref['trailer'][1]['/Encrypt'])) { $this->error('File is encrypted!'); } } /** * Find/Return /Root * * @return array */ public function pdf_find_root() { if ($this->xref['trailer'][1]['/Root'][0] != PDF_TYPE_OBJREF) { $this->error('Wrong Type of Root-Element! Must be an indirect reference'); } return $this->xref['trailer'][1]['/Root']; } /** * Read the /Root */ public function pdf_read_root() { // read root $this->root = $this->pdf_resolve_object($this->c, $this->pdf_find_root()); } /** * Get PDF-Version * * And reset the PDF Version used in FPDI if needed */ public function getPDFVersion() { fseek($this->f, 0); preg_match('/\d\.\d/', fread($this->f, 16), $m); if (isset($m[0])) { $this->pdfVersion = $m[0]; } return $this->pdfVersion; } /** * Find the xref-Table */ public function pdf_find_xref() { $toRead = 1500; $stat = fseek($this->f, -$toRead, SEEK_END); if ($stat === -1) { fseek($this->f, 0); } $data = fread($this->f, $toRead); $pos = strlen($data) - strpos(strrev($data), strrev('startxref')); $data = substr($data, $pos); if (!preg_match('/\s*(\d+).*$/s', $data, $matches)) { $this->error('Unable to find pointer to xref table'); } return (int) $matches[1]; } /** * Read xref-table * * @param array $result Array of xref-table * @param integer $offset of xref-table */ public function pdf_read_xref(&$result, $offset) { $o_pos = $offset-min(20, $offset); fseek($this->f, $o_pos); // set some bytes backwards to fetch errorious docs $data = fread($this->f, 100); $xrefPos = strrpos($data, 'xref'); if ($xrefPos === false) { fseek($this->f, $offset); $c = new pdf_context($this->f); $xrefStreamObjDec = $this->pdf_read_value($c); if (is_array($xrefStreamObjDec) && isset($xrefStreamObjDec[0]) && $xrefStreamObjDec[0] == PDF_TYPE_OBJDEC) { $this->error(sprintf('This document (%s) probably uses a compression technique which is not supported by the free parser shipped with FPDI.', $this->filename)); } else { $this->error('Unable to find xref table.'); } } if (!isset($result['xref_location'])) { $result['xref_location'] = $o_pos+$xrefPos; $result['max_object'] = 0; } $cylces = -1; $bytesPerCycle = 100; fseek($this->f, $o_pos = $o_pos+$xrefPos+4); // set the handle directly after the "xref"-keyword $data = fread($this->f, $bytesPerCycle); while (($trailerPos = strpos($data, 'trailer', max($bytesPerCycle*$cylces++, 0))) === false && !feof($this->f)) { $data .= fread($this->f, $bytesPerCycle); } if ($trailerPos === false) { $this->error('Trailer keyword not found after xref table'); } $data = substr($data, 0, $trailerPos); // get Line-Ending preg_match_all("/(\r\n|\n|\r)/", substr($data, 0, 100), $m); // check the first 100 bytes for linebreaks $differentLineEndings = count(array_unique($m[0])); if ($differentLineEndings > 1) { $lines = preg_split("/(\r\n|\n|\r)/", $data, -1, PREG_SPLIT_NO_EMPTY); } else { $lines = explode($m[0][1], $data); } $data = $differentLineEndings = $m = null; unset($data, $differentLineEndings, $m); $linesCount = count($lines); $start = 1; for ($i = 0; $i < $linesCount; $i++) { $line = trim($lines[$i]); if ($line) { $pieces = explode(' ', $line); $c = count($pieces); switch ($c) { case 2: $start = (int)$pieces[0]; $end = $start+(int)$pieces[1]; if ($end > $result['max_object']) { $result['max_object'] = $end; } break; case 3: if (!isset($result['xref'][$start])) { $result['xref'][$start] = array(); } if (!array_key_exists($gen = (int) $pieces[1], $result['xref'][$start])) { $result['xref'][$start][$gen] = $pieces[2] == 'n' ? (int) $pieces[0] : null; } $start++; break; default: $this->error('Unexpected data in xref table'); } } } $lines = $pieces = $line = $start = $end = $gen = null; unset($lines, $pieces, $line, $start, $end, $gen); fseek($this->f, $o_pos+$trailerPos+7); $c = new pdf_context($this->f); $trailer = $this->pdf_read_value($c); $c = null; unset($c); if (!isset($result['trailer'])) { $result['trailer'] = $trailer; } if (isset($trailer[1]['/Prev'])) { $this->pdf_read_xref($result, $trailer[1]['/Prev'][1]); } $trailer = null; unset($trailer); return true; } /** * Reads an Value * * @param object $c pdf_context * @param string $token a Token * @return mixed */ public function pdf_read_value(&$c, $token = null) { if (is_null($token)) { $token = $this->pdf_read_token($c); } if ($token === false) { return false; } switch ($token) { case '<': // This is a hex string. // Read the value, then the terminator $pos = $c->offset; while (1) { $match = strpos($c->buffer, '>', $pos); // If you can't find it, try // reading more data from the stream if ($match === false) { if (!$c->increase_length()) { return false; } else { continue; } } $result = substr($c->buffer, $c->offset, $match - $c->offset); $c->offset = $match + 1; return array(PDF_TYPE_HEX, $result); } break; case '<<': // This is a dictionary. $result = array(); // Recurse into this function until we reach // the end of the dictionary. while (($key = $this->pdf_read_token($c)) !== '>>') { if ($key === false) { return false; } if (($value = $this->pdf_read_value($c)) === false) { return false; } // Catch missing value if ($value[0] == PDF_TYPE_TOKEN && $value[1] == '>>') { $result[$key] = array(PDF_TYPE_NULL); break; } $result[$key] = $value; } return array(PDF_TYPE_DICTIONARY, $result); case '[': // This is an array. $result = array(); // Recurse into this function until we reach // the end of the array. while (($token = $this->pdf_read_token($c)) !== ']') { if ($token === false) { return false; } if (($value = $this->pdf_read_value($c, $token)) === false) { return false; } $result[] = $value; } return array(PDF_TYPE_ARRAY, $result); case '(': // This is a string $pos = $c->offset; $openBrackets = 1; do { for (; $openBrackets != 0 && $pos < $c->length; $pos++) { switch (ord($c->buffer[$pos])) { case 0x28: // '(' $openBrackets++; break; case 0x29: // ')' $openBrackets--; break; case 0x5C: // backslash $pos++; } } } while ($openBrackets != 0 && $c->increase_length()); $result = substr($c->buffer, $c->offset, $pos - $c->offset - 1); $c->offset = $pos; return array(PDF_TYPE_STRING, $result); case 'stream': $o_pos = ftell($c->file)-strlen($c->buffer); $o_offset = $c->offset; $c->reset($startpos = $o_pos + $o_offset); $e = 0; // ensure line breaks in front of the stream if ($c->buffer[0] == chr(10) || $c->buffer[0] == chr(13)) { $e++; } if ($c->buffer[1] == chr(10) && $c->buffer[0] != chr(10)) { $e++; } if ($this->actual_obj[1][1]['/Length'][0] == PDF_TYPE_OBJREF) { $tmp_c = new pdf_context($this->f); $tmp_length = $this->pdf_resolve_object($tmp_c, $this->actual_obj[1][1]['/Length']); $length = $tmp_length[1][1]; } else { $length = $this->actual_obj[1][1]['/Length'][1]; } if ($length > 0) { $c->reset($startpos+$e, $length); $v = $c->buffer; } else { $v = ''; } $c->reset($startpos+$e+$length+9); // 9 = strlen("endstream") return array(PDF_TYPE_STREAM, $v); default: if (is_numeric($token)) { // A numeric token. Make sure that // it is not part of something else. if (($tok2 = $this->pdf_read_token($c)) !== false) { if (is_numeric($tok2)) { // Two numeric tokens in a row. // In this case, we're probably in // front of either an object reference // or an object specification. // Determine the case and return the data if (($tok3 = $this->pdf_read_token($c)) !== false) { switch ($tok3) { case 'obj': return array(PDF_TYPE_OBJDEC, (int) $token, (int) $tok2); case 'R': return array(PDF_TYPE_OBJREF, (int) $token, (int) $tok2); } // If we get to this point, that numeric value up // there was just a numeric value. Push the extra // tokens back into the stack and return the value. array_push($c->stack, $tok3); } } array_push($c->stack, $tok2); } if ($token === (string)((int)$token)) { return array(PDF_TYPE_NUMERIC, (int)$token); } else { return array(PDF_TYPE_REAL, (float)$token); } } elseif ($token == 'true' || $token == 'false') { return array(PDF_TYPE_BOOLEAN, $token == 'true'); } elseif ($token == 'null') { return array(PDF_TYPE_NULL); } else { // Just a token. Return it. return array(PDF_TYPE_TOKEN, $token); } } } /** * Resolve an object * * @param object $c pdf_context * @param array $obj_spec The object-data * @param boolean $encapsulate Must set to true, cause the parsing and fpdi use this method only without this para */ public function pdf_resolve_object(&$c, $obj_spec, $encapsulate = true) { // Exit if we get invalid data if (!is_array($obj_spec)) { $ret = false; return $ret; } if ($obj_spec[0] == PDF_TYPE_OBJREF) { // This is a reference, resolve it if (isset($this->xref['xref'][$obj_spec[1]][$obj_spec[2]])) { // Save current file position // This is needed if you want to resolve // references while you're reading another object // (e.g.: if you need to determine the length // of a stream) $old_pos = ftell($c->file); // Reposition the file pointer and // load the object header. $c->reset($this->xref['xref'][$obj_spec[1]][$obj_spec[2]]); $header = $this->pdf_read_value($c); if ($header[0] != PDF_TYPE_OBJDEC || $header[1] != $obj_spec[1] || $header[2] != $obj_spec[2]) { $toSearchFor = $obj_spec[1].' '.$obj_spec[2].' obj'; if (preg_match('/'.$toSearchFor.'/', $c->buffer)) { $c->offset = strpos($c->buffer, $toSearchFor) + strlen($toSearchFor); // reset stack $c->stack = array(); } else { $this->error("Unable to find object ({$obj_spec[1]}, {$obj_spec[2]}) at expected location"); } } // If we're being asked to store all the information // about the object, we add the object ID and generation // number for later use $result = array(); $this->actual_obj =& $result; if ($encapsulate) { $result = array( PDF_TYPE_OBJECT, 'obj' => $obj_spec[1], 'gen' => $obj_spec[2] ); } // Now simply read the object data until // we encounter an end-of-object marker while (1) { $value = $this->pdf_read_value($c); if ($value === false || count($result) > 4) { // in this case the parser coudn't find an endobj so we break here break; } if ($value[0] == PDF_TYPE_TOKEN && $value[1] === 'endobj') { break; } $result[] = $value; } $c->reset($old_pos); if (isset($result[2][0]) && $result[2][0] == PDF_TYPE_STREAM) { $result[0] = PDF_TYPE_STREAM; } return $result; } } else { return $obj_spec; } } /** * Reads a token from the file * * @param object $c pdf_context * @return mixed */ public function pdf_read_token(&$c) { // If there is a token available // on the stack, pop it out and // return it. if (count($c->stack)) { return array_pop($c->stack); } // Strip away any whitespace do { if (!$c->ensure_content()) { return false; } $c->offset += strspn($c->buffer, " \n\r\t", $c->offset); } while ($c->offset >= $c->length - 1); // Get the first character in the stream $char = $c->buffer[$c->offset++]; switch ($char) { case '[': case ']': case '(': case ')': // This is either an array or literal string // delimiter, Return it return $char; case '<': case '>': // This could either be a hex string or // dictionary delimiter. Determine the // appropriate case and return the token if ($c->buffer[$c->offset] == $char) { if (!$c->ensure_content()) { return false; } $c->offset++; return $char . $char; } else { return $char; } // no break case '%': // This is a comment - jump over it! $pos = $c->offset; while (1) { $match = preg_match("/(\r\n|\r|\n)/", $c->buffer, $m, PREG_OFFSET_CAPTURE, $pos); if ($match === 0) { if (!$c->increase_length()) { return false; } else { continue; } } $c->offset = $m[0][1]+strlen($m[0][0]); return $this->pdf_read_token($c); } // no break default: // This is "another" type of token (probably // a dictionary entry or a numeric value) // Find the end and return it. if (!$c->ensure_content()) { return false; } while (1) { // Determine the length of the token $pos = strcspn($c->buffer, " %[]<>()\r\n\t/", $c->offset); if ($c->offset + $pos <= $c->length - 1) { break; } else { // If the script reaches this point, // the token may span beyond the end // of the current buffer. Therefore, // we increase the size of the buffer // and try again--just to be safe. $c->increase_length(); } } $result = substr($c->buffer, $c->offset - 1, $pos + 1); $c->offset += $pos; return $result; } } } }