File Source for Parser.php

<?php
/**
* PHP_ParserGenerator, a php 5 parser generator.
*
* This is a direct port of the Lemon parser generator, found at
* {@link http://www.hwaci.com/sw/lemon/}
*
* PHP version 5
*
* LICENSE: This source file is subject to version 3.01 of the PHP license
* that is available through the world-wide-web at the following URI:
* http://www.php.net/license/3_01.txt. If you did not receive a copy of
* the PHP License and are unable to obtain it through the web, please
* send a note to license@php.net so we can mail you a copy immediately.
*
* @category php
* @package PHP_ParserGenerator
* @author Gregory Beaver <cellog@php.net>
* @copyright 2006 Gregory Beaver
* @license http://www.php.net/license/3_01.txt PHP License 3.01
* @version CVS: $Id$
* @since File available since Release 0.1.0
*/
/**
* The grammar parser for lemon grammar files.
*
* @package PHP_ParserGenerator
* @author Gregory Beaver <cellog@php.net>
* @copyright 2006 Gregory Beaver
* @license http://www.php.net/license/3_01.txt PHP License 3.01
* @since Class available since Release 0.1.0
*/
class PHP_ParserGenerator_Parser
{
const INITIALIZE = 1;
const WAITING_FOR_DECL_OR_RULE = 2;
const WAITING_FOR_DECL_KEYWORD = 3;
const WAITING_FOR_DECL_ARG = 4;
const WAITING_FOR_PRECEDENCE_SYMBOL = 5;
const WAITING_FOR_ARROW = 6;
const IN_RHS = 7;
const LHS_ALIAS_1 = 8;
const LHS_ALIAS_2 = 9;
const LHS_ALIAS_3 = 10;
const RHS_ALIAS_1 = 11;
const RHS_ALIAS_2 = 12;
const PRECEDENCE_MARK_1 = 13;
const PRECEDENCE_MARK_2 = 14;
const RESYNC_AFTER_RULE_ERROR = 15;
const RESYNC_AFTER_DECL_ERROR = 16;
const WAITING_FOR_DESTRUCTOR_SYMBOL = 17;
const WAITING_FOR_DATATYPE_SYMBOL = 18;
const WAITING_FOR_FALLBACK_ID = 19;
/**
* Name of the input file
*
* @var string
*/
public $filename;
/**
* Linenumber at which current token starts
* @var int
*/
public $tokenlineno;
/**
* Number of parsing errors so far
* @var int
*/
public $errorcnt;
/**
* Index of current token within the input string
* @var int
*/
public $tokenstart;
/**
* Global state vector
* @var PHP_ParserGenerator_Data
*/
public $gp;
/**
* Parser state (one of the class constants for this class)
*
* - PHP_ParserGenerator_Parser::INITIALIZE,
* - PHP_ParserGenerator_Parser::WAITING_FOR_DECL_OR_RULE,
* - PHP_ParserGenerator_Parser::WAITING_FOR_DECL_KEYWORD,
* - PHP_ParserGenerator_Parser::WAITING_FOR_DECL_ARG,
* - PHP_ParserGenerator_Parser::WAITING_FOR_PRECEDENCE_SYMBOL,
* - PHP_ParserGenerator_Parser::WAITING_FOR_ARROW,
* - PHP_ParserGenerator_Parser::IN_RHS,
* - PHP_ParserGenerator_Parser::LHS_ALIAS_1,
* - PHP_ParserGenerator_Parser::LHS_ALIAS_2,
* - PHP_ParserGenerator_Parser::LHS_ALIAS_3,
* - PHP_ParserGenerator_Parser::RHS_ALIAS_1,
* - PHP_ParserGenerator_Parser::RHS_ALIAS_2,
* - PHP_ParserGenerator_Parser::PRECEDENCE_MARK_1,
* - PHP_ParserGenerator_Parser::PRECEDENCE_MARK_2,
* - PHP_ParserGenerator_Parser::RESYNC_AFTER_RULE_ERROR,
* - PHP_ParserGenerator_Parser::RESYNC_AFTER_DECL_ERROR,
* - PHP_ParserGenerator_Parser::WAITING_FOR_DESTRUCTOR_SYMBOL,
* - PHP_ParserGenerator_Parser::WAITING_FOR_DATATYPE_SYMBOL,
* - PHP_ParserGenerator_Parser::WAITING_FOR_FALLBACK_ID
* @var int
*/
public $state;
/**
* The fallback token
* @var PHP_ParserGenerator_Symbol
*/
public $fallback;
/**
* Left-hand side of the current rule
* @var PHP_ParserGenerator_Symbol
*/
public $lhs;
/**
* Alias for the LHS
* @var string
*/
public $lhsalias;
/**
* Number of right-hand side symbols seen
* @var int
*/
public $nrhs;
/**
* Right-hand side symbols
* @var array array of {@link PHP_ParserGenerator_Symbol} objects
*/
public $rhs = array();
/**
* Aliases for each RHS symbol name (or NULL)
* @var array array of strings
*/
public $alias = array();
/**
* Previous rule parsed
* @var PHP_ParserGenerator_Rule
*/
public $prevrule;
/**
* Keyword of a declaration
*
* This is one of the %keyword keywords in the grammar file
* @var string
*/
public $declkeyword;
/**
* Where the declaration argument should be put
*
* This is assigned as a reference to an internal variable
* @var mixed
*/
public $declargslot = array();
/**
* Where the declaration linenumber is put
*
* This is assigned as a reference to an internal variable
* @var mixed
*/
public $decllnslot;
/*enum e_assoc*/
public $declassoc; /* Assign this association to decl arguments */
public $preccounter; /* Assign this precedence to decl arguments */
/**
* @var PHP_ParserGenerator_Rule
*/
public $firstrule; /* Pointer to first rule in the grammar */
/**
* @var PHP_ParserGenerator_Rule
*/
public $lastrule; /* Pointer to the most recently parsed rule */
/**
* @var PHP_ParserGenerator
*/
private $lemon;
function __construct(PHP_ParserGenerator $lem)
{
$this->lemon = $lem;
}
/**
* Run the preprocessor over the input file text. The Lemon variable
* $azDefine contains the names of all defined
* macros. This routine looks for "%ifdef" and "%ifndef" and "%endif" and
* comments them out. Text in between is also commented out as appropriate.
* @param string
*/
private function preprocess_input(&$z)
{
$lineno = $exclude = 0;
for ($i=0; $i < strlen($z); $i++) {
if ($z[$i] == "\n") {
$lineno++;
}
if ($z[$i] != '%' || ($i > 0 && $z[$i-1] != "\n")) {
continue;
}
if (substr($z, $i, 6) === "%endif" && trim($z[$i+6]) === '') {
if ($exclude) {
$exclude--;
if ($exclude === 0) {
for ($j = $start; $j < $i; $j++) {
if ($z[$j] != "\n") $z[$j] = ' ';
}
}
}
for ($j = $i; $j < strlen($z) && $z[$j] != "\n"; $j++) {
$z[$j] = ' ';
}
} elseif (substr($z, $i, 6) === "%ifdef" && trim($z[$i+6]) === '' ||
substr($z, $i, 7) === "%ifndef" && trim($z[$i+7]) === '') {
if ($exclude) {
$exclude++;
} else {
$j = $i;
$n = strtok(substr($z, $j), " \t");
$exclude = 1;
if (isset($this->lemon->azDefine[$n])) {
$exclude = 0;
}
if ($z[$i + 3]=='n') {
// this is a rather obtuse way of checking whether this is %ifndef
$exclude = !$exclude;
}
if ($exclude) {
$start = $i;
$start_lineno = $lineno;
}
}
//for ($j = $i; $j < strlen($z) && $z[$j] != "\n"; $j++) $z[$j] = ' ';
$j = strpos(substr($z, $i), "\n");
if ($j === false) {
$z = substr($z, 0, $i); // remove instead of adding ' '
} else {
$z = substr($z, 0, $i) . substr($z, $i + $j); // remove instead of adding ' '
}
}
}
if ($exclude) {
throw new Exception("unterminated %ifdef starting on line $start_lineno\n");
}
}
/**
* In spite of its name, this function is really a scanner.
*
* It reads in the entire input file (all at once) then tokenizes it.
* Each token is passed to the function "parseonetoken" which builds all
* the appropriate data structures in the global state vector "gp".
* @param PHP_ParserGenerator_Data
*/
function Parse(PHP_ParserGenerator_Data $gp)
{
$startline = 0;
$this->gp = $gp;
$this->filename = $gp->filename;
$this->errorcnt = 0;
$this->state = self::INITIALIZE;
/* Begin by reading the input file */
$filebuf = file_get_contents($this->filename);
if (!$filebuf) {
PHP_ParserGenerator::ErrorMsg($this->filename, 0, "Can't open this file for reading.");
$gp->errorcnt++;
return;
}
if (filesize($this->filename) != strlen($filebuf)) {
ErrorMsg($this->filename, 0, "Can't read in all %d bytes of this file.",
filesize($this->filename));
$gp->errorcnt++;
return;
}
/* Make an initial pass through the file to handle %ifdef and %ifndef */
$this->preprocess_input($filebuf);
/* Now scan the text of the input file */
$lineno = 1;
for ($cp = 0, $c = $filebuf[0]; $cp < strlen($filebuf); $cp++) {
$c = $filebuf[$cp];
if ($c == "\n") $lineno++; /* Keep track of the line number */
if (trim($c) === '') {
continue;
} /* Skip all white space */
if ($filebuf[$cp] == '/' && ($cp + 1 < strlen($filebuf)) && $filebuf[$cp + 1] == '/') {
/* Skip C++ style comments */
$cp += 2;
$z = strpos(substr($filebuf, $cp), "\n");
if ($z === false) {
$cp = strlen($filebuf);
break;
}
$lineno++;
$cp += $z;
continue;
}
if ($filebuf[$cp] == '/' && ($cp + 1 < strlen($filebuf)) && $filebuf[$cp + 1] == '*') {
/* Skip C style comments */
$cp += 2;
$z = strpos(substr($filebuf, $cp), '*/');
if ($z !== false) {
$lineno += count(explode("\n", substr($filebuf, $cp, $z))) - 1;
}
$cp += $z + 1;
continue;
}
$this->tokenstart = $cp; /* Mark the beginning of the token */
$this->tokenlineno = $lineno; /* Linenumber on which token begins */
if ($filebuf[$cp] == '"') { /* String literals */
$cp++;
$oldcp = $cp;
$test = strpos(substr($filebuf, $cp), '"');
if ($test === false) {
PHP_ParserGenerator::ErrorMsg($this->filename, $startline,
"String starting on this line is not terminated before the end of the file.");
$this->errorcnt++;
$nextcp = $cp = strlen($filebuf);
} else {
$cp += $test;
$nextcp = $cp + 1;
}
$lineno += count(explode("\n", substr($filebuf, $oldcp, $cp - $oldcp))) - 1;
} elseif ($filebuf[$cp] == '{') { /* A block of C code */
$cp++;
for ($level = 1; $cp < strlen($filebuf) && ($level > 1 || $filebuf[$cp] != '}'); $cp++) {
if ($filebuf[$cp] == "\n") {
$lineno++;
} elseif ($filebuf[$cp] == '{') {
$level++;
} elseif ($filebuf[$cp] == '}') {
$level--;
} elseif ($filebuf[$cp] == '/' && $filebuf[$cp + 1] == '*') {
/* Skip comments */
$cp += 2;
$z = strpos(substr($filebuf, $cp), '*/');
if ($z !== false) {
$lineno += count(explode("\n", substr($filebuf, $cp, $z))) - 1;
}
$cp += $z + 2;
} elseif ($filebuf[$cp] == '/' && $filebuf[$cp + 1] == '/') {
/* Skip C++ style comments too */
$cp += 2;
$z = strpos(substr($filebuf, $cp), "\n");
if ($z === false) {
$cp = strlen($filebuf);
break;
} else {
$lineno++;
}
$cp += $z;
} elseif ($filebuf[$cp] == "'" || $filebuf[$cp] == '"') {
/* String a character literals */
$startchar = $filebuf[$cp];
$prevc = 0;
for ($cp++; $cp < strlen($filebuf) && ($filebuf[$cp] != $startchar || $prevc === '\\'); $cp++) {
if ($filebuf[$cp] == "\n") {
$lineno++;
}
if ($prevc === '\\') {
$prevc = 0;
} else {
$prevc = $filebuf[$cp];
}
}
}
}
if ($cp >= strlen($filebuf)) {
PHP_ParserGenerator::ErrorMsg($this->filename, $this->tokenlineno,
"PHP code starting on this line is not terminated before the end of the file.");
$this->errorcnt++;
$nextcp = $cp;
} else {
$nextcp = $cp + 1;
}
} elseif (preg_match('/[a-zA-Z0-9]/', $filebuf[$cp])) {
/* Identifiers */
preg_match('/[a-zA-Z0-9_]+/', substr($filebuf, $cp), $preg_results);
$cp += strlen($preg_results[0]);
$nextcp = $cp;
} elseif ($filebuf[$cp] == ':' && $filebuf[$cp + 1] == ':' &&
$filebuf[$cp + 2] == '=') {
/* The operator "::=" */
$cp += 3;
$nextcp = $cp;
} elseif (($filebuf[$cp] == '/' || $filebuf[$cp] == '|') &&
preg_match('/[a-zA-Z]/', $filebuf[$cp + 1])) {
$cp += 2;
preg_match('/[a-zA-Z0-9_]+/', substr($filebuf, $cp), $preg_results);
$cp += strlen($preg_results[0]);
$nextcp = $cp;
} else {
/* All other (one character) operators */
$cp ++;
$nextcp = $cp;
}
$this->parseonetoken(substr($filebuf, $this->tokenstart,
$cp - $this->tokenstart)); /* Parse the token */
$cp = $nextcp - 1;
}
$gp->rule = $this->firstrule;
$gp->errorcnt = $this->errorcnt;
}
/**
* Parse a single token
* @param string token
*/
function parseonetoken($token)
{
$x = $token;
$this->a = 0; // for referencing in WAITING_FOR_DECL_KEYWORD
if (PHP_ParserGenerator::DEBUG) {
printf("%s:%d: Token=[%s] state=%d\n",
$this->filename, $this->tokenlineno, $token, $this->state);
}
switch ($this->state) {
case self::INITIALIZE:
$this->prevrule = 0;
$this->preccounter = 0;
$this->firstrule = $this->lastrule = 0;
$this->gp->nrule = 0;
/* Fall thru to next case */
case self::WAITING_FOR_DECL_OR_RULE:
if ($x[0] == '%') {
$this->state = self::WAITING_FOR_DECL_KEYWORD;
} elseif (preg_match('/[a-z]/', $x[0])) {
$this->lhs = PHP_ParserGenerator_Symbol::Symbol_new($x);
$this->nrhs = 0;
$this->lhsalias = 0;
$this->state = self::WAITING_FOR_ARROW;
} elseif ($x[0] == '{') {
if ($this->prevrule === 0) {
PHP_ParserGenerator::ErrorMsg($this->filename, $this->tokenlineno,
&nb

	PHP_ParserGenerator

[ class tree: PHP_ParserGenerator ] [ index: PHP_ParserGenerator ] [ all elements ]

Source for file Parser.php