adodb-csvlib.inc.php

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<?php

// security - hide paths
if (!defined('ADODB_DIR')) die();

global $ADODB_INCLUDED_CSV;
$ADODB_INCLUDED_CSV = 1;

/*

  V5.19  23-Apr-2014  (c) 2000-2014 John Lim (jlim#natsoft.com). All rights reserved.
  Released under both BSD license and Lesser GPL library license.
  Whenever there is any discrepancy between the two licenses,
  the BSD license will take precedence. See License.txt.
  Set tabs to 4 for best viewing.

  Latest version is available at http://adodb.sourceforge.net

  Library for CSV serialization. This is used by the csv/proxy driver and is the
  CacheExecute() serialization format.

  ==== NOTE ====
  Format documented at http://php.weblogs.com/ADODB_CSV
  ==============
*/

    function _rs2serialize(&$rs,$conn=false,$sql='')
    {
        $max = ($rs) ? $rs->FieldCount() : 0;

        if ($sql) $sql = urlencode($sql);
        // metadata setup

        if ($max <= 0 || $rs->dataProvider == 'empty') { // is insert/update/delete
            if (is_object($conn)) {
                $sql .= ','.$conn->Affected_Rows();
                $sql .= ','.$conn->Insert_ID();
            } else
                $sql .= ',,';

            $text = "====-1,0,$sql\n";
            return $text;
        }
        $tt = ($rs->timeCreated) ? $rs->timeCreated : time();

        ## changed format from ====0 to ====1
        $line = "====1,$tt,$sql\n";

        if ($rs->databaseType == 'array') {
            $rows = $rs->_array;
        } else {
            $rows = array();
            while (!$rs->EOF) {
                $rows[] = $rs->fields;
                $rs->MoveNext();
            }
        }

        for($i=0; $i < $max; $i++) {
            $o = $rs->FetchField($i);
            $flds[] = $o;
        }

        $savefetch = isset($rs->adodbFetchMode) ? $rs->adodbFetchMode : $rs->fetchMode;
        $class = $rs->connection->arrayClass;
        $rs2 = new $class();
        $rs2->timeCreated = $rs->timeCreated; # memcache fix
        $rs2->sql = $rs->sql;
        $rs2->oldProvider = $rs->dataProvider;
        $rs2->InitArrayFields($rows,$flds);
        $rs2->fetchMode = $savefetch;
        return $line.serialize($rs2);
    }


    function csv2rs($url,&$err,$timeout=0, $rsclass='ADORecordSet_array')
    {
        $false = false;
        $err = false;
        $fp = @fopen($url,'rb');
        if (!$fp) {
            $err = $url.' file/URL not found';
            return $false;
        }
        @flock($fp, LOCK_SH);
        $arr = array();
        $ttl = 0;

        if ($meta = fgetcsv($fp, 32000, ",")) {
            // check if error message
            if (strncmp($meta[0],'****',4) === 0) {
                $err = trim(substr($meta[0],4,1024));
                fclose($fp);
                return $false;
            }
            // check for meta data
            // $meta[0] is -1 means return an empty recordset
            // $meta[1] contains a time

            if (strncmp($meta[0], '====',4) === 0) {

                if ($meta[0] == "====-1") {
                    if (sizeof($meta) < 5) {
                        $err = "Corrupt first line for format -1";
                        fclose($fp);
                        return $false;
                    }
                    fclose($fp);

                    if ($timeout > 0) {
                        $err = " Illegal Timeout $timeout ";
                        return $false;
                    }

                    $rs = new $rsclass($val=true);
                    $rs->fields = array();
                    $rs->timeCreated = $meta[1];
                    $rs->EOF = true;
                    $rs->_numOfFields = 0;
                    $rs->sql = urldecode($meta[2]);
                    $rs->affectedrows = (integer)$meta[3];
                    $rs->insertid = $meta[4];
                    return $rs;
                }
            # Under high volume loads, we want only 1 thread/process to _write_file
            # so that we don't have 50 processes queueing to write the same data.
            # We use probabilistic timeout, ahead of time.
            #
            # -4 sec before timeout, give processes 1/32 chance of timing out
            # -2 sec before timeout, give processes 1/16 chance of timing out
            # -1 sec after timeout give processes 1/4 chance of timing out
            # +0 sec after timeout, give processes 100% chance of timing out
                if (sizeof($meta) > 1) {
                    if($timeout >0){
                        $tdiff = (integer)( $meta[1]+$timeout - time());
                        if ($tdiff <= 2) {
                            switch($tdiff) {
                            case 4:
                            case 3:
                                if ((rand() & 31) == 0) {
                                    fclose($fp);
                                    $err = "Timeout 3";
                                    return $false;
                                }
                                break;
                            case 2:
                                if ((rand() & 15) == 0) {
                                    fclose($fp);
                                    $err = "Timeout 2";
                                    return $false;
                                }
                                break;
                            case 1:
                                if ((rand() & 3) == 0) {
                                    fclose($fp);
                                    $err = "Timeout 1";
                                    return $false;
                                }
                                break;
                            default:
                                fclose($fp);
                                $err = "Timeout 0";
                                return $false;
                            } // switch

                        } // if check flush cache
                    }// (timeout>0)
                    $ttl = $meta[1];
                }
                //================================================
                // new cache format - use serialize extensively...
                if ($meta[0] === '====1') {
                    // slurp in the data
                    $MAXSIZE = 128000;

                    $text = fread($fp,$MAXSIZE);
                    if (strlen($text)) {
                        while ($txt = fread($fp,$MAXSIZE)) {
                            $text .= $txt;
                        }
                    }
                    fclose($fp);
                    $rs = unserialize($text);
                    if (is_object($rs)) $rs->timeCreated = $ttl;
                    else {
                        $err = "Unable to unserialize recordset";
                        //echo htmlspecialchars($text),' !--END--!<p>';
                    }
                    return $rs;
                }

                $meta = false;
                $meta = fgetcsv($fp, 32000, ",");
                if (!$meta) {
                    fclose($fp);
                    $err = "Unexpected EOF 1";
                    return $false;
                }
            }

            // Get Column definitions
            $flds = array();
            foreach($meta as $o) {
                $o2 = explode(':',$o);
                if (sizeof($o2)!=3) {
                    $arr[] = $meta;
                    $flds = false;
                    break;
                }
                $fld = new ADOFieldObject();
                $fld->name = urldecode($o2[0]);
                $fld->type = $o2[1];
                $fld->max_length = $o2[2];
                $flds[] = $fld;
            }
        } else {
            fclose($fp);
            $err = "Recordset had unexpected EOF 2";
            return $false;
        }

        // slurp in the data
        $MAXSIZE = 128000;

        $text = '';
        while ($txt = fread($fp,$MAXSIZE)) {
            $text .= $txt;
        }

        fclose($fp);
        @$arr = unserialize($text);
        //var_dump($arr);
        if (!is_array($arr)) {
            $err = "Recordset had unexpected EOF (in serialized recordset)";
            if (get_magic_quotes_runtime()) $err .= ". Magic Quotes Runtime should be disabled!";
            return $false;
        }
        $rs = new $rsclass();
        $rs->timeCreated = $ttl;
        $rs->InitArrayFields($arr,$flds);
        return $rs;
    }


    function adodb_write_file($filename, $contents,$debug=false)
    {
    # http://www.php.net/bugs.php?id=9203 Bug that flock fails on Windows
    # So to simulate locking, we assume that rename is an atomic operation.
    # First we delete $filename, then we create a $tempfile write to it and
    # rename to the desired $filename. If the rename works, then we successfully
    # modified the file exclusively.
    # What a stupid need - having to simulate locking.
    # Risks:
    # 1. $tempfile name is not unique -- very very low
    # 2. unlink($filename) fails -- ok, rename will fail
    # 3. adodb reads stale file because unlink fails -- ok, $rs timeout occurs
    # 4. another process creates $filename between unlink() and rename() -- ok, rename() fails and  cache updated
        if (strncmp(PHP_OS,'WIN',3) === 0) {
            // skip the decimal place
            $mtime = substr(str_replace(' ','_',microtime()),2);
            // getmypid() actually returns 0 on Win98 - never mind!
            $tmpname = $filename.uniqid($mtime).getmypid();
            if (!($fd = @fopen($tmpname,'w'))) return false;
            if (fwrite($fd,$contents)) $ok = true;
            else $ok = false;
            fclose($fd);

            if ($ok) {
                @chmod($tmpname,0644);
                // the tricky moment
                @unlink($filename);
                if (!@rename($tmpname,$filename)) {
                    unlink($tmpname);
                    $ok = 0;
                }
                if (!$ok) {
                    if ($debug) ADOConnection::outp( " Rename $tmpname ".($ok? 'ok' : 'failed'));
                }
            }
            return $ok;
        }
        if (!($fd = @fopen($filename, 'a'))) return false;
        if (flock($fd, LOCK_EX) && ftruncate($fd, 0)) {
            if (fwrite( $fd, $contents )) $ok = true;
            else $ok = false;
            fclose($fd);
            @chmod($filename,0644);
        }else {
            fclose($fd);
            if ($debug)ADOConnection::outp( " Failed acquiring lock for $filename<br>\n");
            $ok = false;
        }

        return $ok;
    }