<?php
/***************************************************************************
* sql_parse.php
* -------------------
* begin : Thu May 31, 2001
* copyright : (C) 2001 The phpBB Group
* email : support@phpbb.com
*
* $Id: sql_parse.php,v 1.8 2002/03/18 23:53:12 psotfx Exp $
*
****************************************************************************/

/***************************************************************************
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
***************************************************************************/

/***************************************************************************
*
* These functions are mainly for use in the db_utilities under the admin
* however in order to make these functions available elsewhere, specifically
* in the installation phase of phpBB I have seperated out a couple of
* functions into this file. JLH
*
\***************************************************************************/

//
// remove_comments will strip the sql comment lines out of an uploaded sql file
// specifically for mssql and postgres type files in the install....
//
function remove_comments(&$output)
{
$lines = explode("\n", $output);
$output = "";

// try to keep mem. use down
$linecount = count($lines);

$in_comment = false;
for($i = 0; $i < $linecount; $i++)
{
if( preg_match("/^\/\*/", preg_quote($lines[$i])) )
{
$in_comment = true;
}

if( !$in_comment )
{
$output .= $lines[$i] . "\n";
}

if( preg_match("/\*\/$/", preg_quote($lines[$i])) )
{
$in_comment = false;
}
}

unset($lines);
return $output;
}

//
// remove_remarks will strip the sql comment lines out of an uploaded sql file
//
function remove_remarks($sql)
{
$lines = explode("\n", $sql);

// try to keep mem. use down
$sql = "";

$linecount = count($lines);
$output = "";

for ($i = 0; $i < $linecount; $i++)
{
if (($i != ($linecount - 1)) || (strlen($lines[$i]) > 0))
{
if ($lines[$i][0] != "#")
{
$output .= $lines[$i] . "\n";
}
else
{
$output .= "\n";
}
// Trading a bit of speed for lower mem. use here.
$lines[$i] = "";
}
}

return $output;

}

//
// split_sql_file will split an uploaded sql file into single sql statements.
// Note: expects trim() to have already been run on $sql.
//
function split_sql_file($sql, $delimiter)
{
// Split up our string into "possible" SQL statements.
$tokens = explode($delimiter, $sql);

// try to save mem.
$sql = "";
$output = array();

// we don't actually care about the matches preg gives us.
$matches = array();

// this is faster than calling count($oktens) every time thru the loop.
$token_count = count($tokens);
for ($i = 0; $i < $token_count; $i++)
{
// Don't wanna add an empty string as the last thing in the array.
if (($i != ($token_count - 1)) || (strlen($tokens[$i] > 0)))
{
// This is the total number of single quotes in the token.
$total_quotes = preg_match_all("/'/", $tokens[$i], $matches);
// Counts single quotes that are preceded by an odd number of backslashes,
// which means they're escaped quotes.
$escaped_quotes = preg_match_all("/(?<!\\\\)(\\\\\\\\)*\\\\'/", $tokens[$i], $matches);

$unescaped_quotes = $total_quotes - $escaped_quotes;

// If the number of unescaped quotes is even, then the delimiter did NOT occur inside a string literal.
if (($unescaped_quotes % 2) == 0)
{
// It's a complete sql statement.
$output[] = $tokens[$i];
// save memory.
$tokens[$i] = "";
}
else
{
// incomplete sql statement. keep adding tokens until we have a complete one.
// $temp will hold what we have so far.
$temp = $tokens[$i] . $delimiter;
// save memory..
$tokens[$i] = "";

// Do we have a complete statement yet?
$complete_stmt = false;

for ($j = $i + 1; (!$complete_stmt && ($j < $token_count)); $j++)
{
// This is the total number of single quotes in the token.
$total_quotes = preg_match_all("/'/", $tokens[$j], $matches);
// Counts single quotes that are preceded by an odd number of backslashes,
// which means they're escaped quotes.
$escaped_quotes = preg_match_all("/(?<!\\\\)(\\\\\\\\)*\\\\'/", $tokens[$j], $matches);

$unescaped_quotes = $total_quotes - $escaped_quotes;

if (($unescaped_quotes % 2) == 1)
{
// odd number of unescaped quotes. In combination with the previous incomplete
// statement(s), we now have a complete statement. (2 odds always make an even)
$output[] = $temp . $tokens[$j];

// save memory.
$tokens[$j] = "";
$temp = "";

// exit the loop.
$complete_stmt = true;
// make sure the outer loop continues at the right point.
$i = $j;
}
else
{
// even number of unescaped quotes. We still don't have a complete statement.
// (1 odd and 1 even always make an odd)
$temp .= $tokens[$j] . $delimiter;
// save memory.
$tokens[$j] = "";
}

} // for..
} // else
}
}

return $output;
}

?>