/dev/initdata/dbf/includes/dbase.class.php

<?php
/**
 * \file        dev/initdata/dbf/includes/dbase.class.php
 * \ingroup     dev
 * \brief       Class to manage DBF databases
 */

// source : https://github.com/donfbecker/php-dbase

define('DBASE_RDONLY', 0);
define('DBASE_WRONLY', 1);
define('DBASE_RDWR', 2);
define('DBASE_TYPE_DBASE', 0);
define('DBASE_TYPE_FOXPRO', 1);

/**
 * Class for DBase
 */
class DBase
{
    private $fd;
    private $headerLength = 0;
    private $fields = array();
    private $fieldCount = 0;
    private $recordLength = 0;
    private $recordCount = 0;

    //resource dbase_open ( string $filename , int $mode )
    public static function open($filename, $mode)
	{
        if (!file_exists($filename))
            return false;
        $modes = array('r', 'w', 'r+');
        $mode = $modes[$mode];
        $fd = fopen($filename, $mode);
        if (!$fd)
            return false;
        return new DBase($fd);
    }

    //resource dbase_create ( string $filename , array $fields [, int $type = DBASE_TYPE_DBASE ] )
    public static function create($filename, $fields, $type = DBASE_TYPE_DBASE)
	{
        if (file_exists($filename))
            return false;
        $fd = fopen($filename, 'c+');
        if (!$fd)
            return false;
        // Byte 0 (1 byte): Valid dBASE for DOS file; bits 0-2 indicate version number, bit 3
        // indicates the presence of a dBASE for DOS memo file, bits 4-6 indicate the
        // presence of a SQL table, bit 7 indicates the presence of any memo file
        // (either dBASE m PLUS or dBASE for DOS)
        self::putChar8($fd, 5);
        // Byte 1-3 (3 bytes): Date of last update; formatted as YYMMDD
        self::putChar8($fd, date('Y') - 1900);
        self::putChar8($fd, date('m'));
        self::putChar8($fd, date('d'));
        // Byte 4-7 (32-bit number): Number of records in the database file.  Currently 0
        self::putInt32($fd, 0);
        // Byte 8-9 (16-bit number): Number of bytes in the header.
        self::putInt16($fd, 32 + (32 * count($fields)) + 1);
        // Byte 10-11 (16-bit number): Number of bytes in record.
        // Make sure the include the byte for deleted flag
        $len = 1;
        foreach ($fields as &$field)
            $len += self::length($field);
        self::putInt16($fd, $len);
        // Byte 12-13 (2 bytes): Reserved, 0 filled.
        self::putInt16($fd, 0);
        // Byte 14 (1 byte): Flag indicating incomplete transaction
        // The ISMARKEDO function checks this flag. BEGIN TRANSACTION sets it to 1, END TRANSACTION and ROLLBACK reset it to 0.
        self::putChar8($fd, 0);
        // Byte 15 (1 byte): Encryption flag. If this flag is set to 1, the message Database encrypted appears. Changing this flag to 0 removes the message, but does not decrypt the file.
        self::putChar8($fd, 0);
        // Byte 16-27 (12 bytes): Reserved for dBASE for DOS in a multi-user environment
        self::putInt32($fd, 0);
        self::putInt32($fd, 0);
        self::putInt32($fd, 0);
        // Byte 28 (1 byte): Production .mdx file flag; 0x01 if there is a production .mdx file, 0x00 if not
        self::putChar8($fd, 0);
        // Byte 29 (1 byte): Language driver ID
        // (no clue what this is)
        self::putChar8($fd, 0);
        // Byte 30-31 (2 bytes): Reserved, 0 filled.
        self::putInt16($fd, 0);
        // Byte 32 - n (32 bytes each): Field descriptor array
        foreach ($fields as &$field) {
            self::putString($fd, $field[0], 11);       // Byte 0 - 10 (11 bytes): Field name in ASCII (zero-filled)
            self::putString($fd, $field[1], 1);       // Byte 11 (1 byte): Field type in ASCII (C, D, F, L, M, or N)
            self::putInt32($fd, 0);                    // Byte 12 - 15 (4 bytes): Reserved
            self::putChar8($fd, self::length($field)); // Byte 16 (1 byte): Field length in binary. The maximum length of a field is 254 (0xFE).
            self::putChar8($fd, $field[3]);            // Byte 17 (1 byte): Field decimal count in binary
            self::putInt16($fd, 0);                    // Byte 18 - 19 (2 bytes): Work area ID
            self::putChar8($fd, 0);                    // Byte 20 (1 byte): Example (??)
            self::putInt32($fd, 0);                    // Byte 21 - 30 (10 bytes): Reserved
            self::putInt32($fd, 0);
            self::putInt16($fd, 0);
            self::putChar8($fd, 0);                    // Byte 31 (1 byte): Production MDX field flag; 1 if field has an index tag in the production MDX file, 0 if not
        }
        // Byte n + 1 (1 byte): 0x0D as the field descriptor array terminator
        self::putChar8($fd, 0x0D);
        return new DBase($fd);
    }

    // Create DBase instance
    private function __construct($fd)
	{
        $this->fd = $fd;
        // Byte 4-7 (32-bit number): Number of records in the database file.  Currently 0
        fseek($this->fd, 4, SEEK_SET);
        $this->recordCount = self::getInt32($fd);
        // Byte 8-9 (16-bit number): Number of bytes in the header.
        fseek($this->fd, 8, SEEK_SET);
        $this->headerLength = self::getInt16($fd);
        // Number of fields is (headerLength - 33) / 32)
        $this->fieldCount = ($this->headerLength - 33) / 32;
        // Byte 10-11 (16-bit number): Number of bytes in record.
        fseek($this->fd, 10, SEEK_SET);
        $this->recordLength = self::getInt16($fd);
        // Byte 32 - n (32 bytes each): Field descriptor array
        fseek($fd, 32, SEEK_SET);
        for ($i = 0; $i < $this->fieldCount; $i++) {
            $data = fread($this->fd, 32);
            $field = array_map('trim', unpack('a11name/a1type/c4/c1length/c1precision/s1workid/c1example/c10/c1production', $data));
            $this->fields[] = $field;
        }
    }

    //bool dbase_close ( resource $dbase_identifier )
    public function close()
	{
        fclose($this->fd);
    }

    //array dbase_get_header_info ( resource $dbase_identifier )
    public function get_header_info()
	{
        return $this->fields;
    }

    //int dbase_numfields ( resource $dbase_identifier )
    public function numfields()
	{
        return $this->fieldCount;
    }

    //int dbase_numrecords ( resource $dbase_identifier )
    public function numrecords()
	{
        return $this->recordCount;
    }

    //bool dbase_add_record ( resource $dbase_identifier , array $record )
    public function add_record($record)
	{
        if (count($record) != $this->fieldCount)
            return false;
        // Seek to end of file, minus the end of file marker
        fseek($this->fd, 0, SEEK_END);
        // Put the deleted flag
        self::putChar8($this->fd, 0x20);
        // Put the record
        if (!$this->putRecord($record))
            return false;
        // Update the record count
        fseek($this->fd, 4);
        self::putInt32($this->fd, ++$this->recordCount);
        return true;
    }

    //bool dbase_replace_record ( resource $dbase_identifier , array $record , int $record_number )
    public function replace_record($record, $record_number)
	{
        if (count($record) != $this->fieldCount)
            return false;
        if ($record_number < 1 || $record_number > $this->recordCount)
            return false;
        // Skip to the record location, plus the 1 byte for the deleted flag
        fseek($this->fd, $this->headerLength + ($this->recordLength * ($record_number - 1)) + 1);
        return $this->putRecord($record);
    }

    //bool dbase_delete_record ( resource $dbase_identifier , int $record_number )
    public function delete_record($record_number)
	{
        if ($record_number < 1 || $record_number > $this->recordCount)
            return false;
        fseek($this->fd, $this->headerLength + ($this->recordLength * ($record_number - 1)));
        self::putChar8($this->fd, 0x2A);
        return true;
    }

    //array dbase_get_record ( resource $dbase_identifier , int $record_number )
    public function get_record($record_number)
	{
        if ($record_number < 1 || $record_number > $this->recordCount)
            return false;
        fseek($this->fd, $this->headerLength + ($this->recordLength * ($record_number - 1)));
        $record = array(
            'deleted' => self::getChar8($this->fd) == 0x2A ? 1 : 0
        );
        foreach ($this->fields as $i => &$field) {
            $value = trim(fread($this->fd, $field['length']));
            if ($field['type'] == 'L') {
                $value = strtolower($value);
                if ($value == 't' || $value == 'y')
                    $value = true;
                elseif ($value == 'f' || $value == 'n')
                    $value = false;
                else
                    $value = null;
            }
            $record[$i] = $value;
        }
        return $record;
    }

    //array dbase_get_record_with_names ( resource $dbase_identifier , int $record_number )
    public function get_record_with_names($record_number)
	{
        if ($record_number < 1 || $record_number > $this->recordCount)
            return false;
        $record = $this->get_record($record_number);
        foreach ($this->fields as $i => &$field) {
            $record[$field['name']] = $record[$i];
            unset($record[$i]);
        }
        return $record;
    }

    //bool dbase_pack ( resource $dbase_identifier )
    public function pack()
	{
        $in_offset = $out_offset = $this->headerLength;
        $new_count = 0;
        $rec_count = $this->recordCount;
        while ($rec_count > 0) {
            fseek($this->fd, $in_offset, SEEK_SET);
            $record = fread($this->fd, $this->recordLength);
            $deleted = substr($record, 0, 1);
            if ($deleted != '*') {
                fseek($this->fd, $out_offset, SEEK_SET);
                fwrite($this->fd, $record);
                $out_offset += $this->recordLength;
                $new_count++;
            }
            $in_offset += $this->recordLength;
            $rec_count--;
        }
        ftruncate($this->fd, $out_offset);
        // Update the record count
        fseek($this->fd, 4);
        self::putInt32($this->fd, $new_count);
    }

    /*
     * A few utilitiy functions
     */

    private static function length($field)
	{
        switch ($field[1]) {
            case 'D': // Date: Numbers and a character to separate month, day, and year (stored internally as 8 digits in YYYYMMDD format)
                return 8;
            case 'T': // DateTime (YYYYMMDDhhmmss.uuu) (FoxPro)
                return 18;
            case 'M': // Memo (ignored): All ASCII characters (stored internally as 10 digits representing a .dbt block number, right justified, padded with whitespaces)
            case 'N': // Number: -.0123456789 (right justified, padded with whitespaces)
            case 'F': // Float: -.0123456789 (right justified, padded with whitespaces)
            case 'C': // String: All ASCII characters (padded with whitespaces up to the field's length)
                return $field[2];
            case 'L': // Boolean: YyNnTtFf? (? when not initialized)
                return 1;
        }
        return 0;
    }

    /*
     * Functions for reading and writing bytes
     */

    private static function getChar8($fd)
	{
        return ord(fread($fd, 1));
    }

    private static function putChar8($fd, $value)
	{
        return fwrite($fd, chr($value));
    }

    private static function getInt16($fd, $n = 1)
	{
        $data = fread($fd, 2 * $n);
        $i = unpack("S$n", $data);
        if ($n == 1)
            return (int) $i[1];
        else
            return array_merge($i);
    }

    private static function putInt16($fd, $value)
	{
        return fwrite($fd, pack('S', $value));
    }

    private static function getInt32($fd, $n = 1)
	{
        $data = fread($fd, 4 * $n);
        $i = unpack("L$n", $data);
        if ($n == 1)
            return (int) $i[1];
        else
            return array_merge($i);
    }

    private static function putInt32($fd, $value)
	{
        return fwrite($fd, pack('L', $value));
    }

    private static function putString($fd, $value, $length = 254)
	{
        $ret = fwrite($fd, pack('A' . $length, $value));
    }

    private function putRecord($record)
	{
        foreach ($this->fields as $i => &$field) {
            $value = $record[$i];
            // Number types are right aligned with spaces
            if ($field['type'] == 'N' || $field['type'] == 'F' && strlen($value) < $field['length']) {
                $value = str_repeat(' ', $field['length'] - strlen($value)) . $value;
            }
            self::putString($this->fd, $value, $field['length']);
        }
        return true;
    }
}

if (!function_exists('dbase_open')) {

    function dbase_open($filename, $mode)
	{
        return DBase::open($filename, $mode);
    }

    function dbase_create($filename, $fields, $type = DBASE_TYPE_DBASE)
	{
        return DBase::create($filename, $fields, $type);
    }

    function dbase_close($dbase_identifier)
	{
        return $dbase_identifier->close();
    }

    function dbase_get_header_info($dbase_identifier)
	{
        return $dbase_identifier->get_header_info();
    }

    function dbase_numfields($dbase_identifier)
	{
        $dbase_identifier->numfields();
    }

    function dbase_numrecords($dbase_identifier)
	{
        return $dbase_identifier->numrecords();
    }

    function dbase_add_record($dbase_identifier, $record)
	{
        return $dbase_identifier->add_record($record);
    }

    function dbase_delete_record($dbase_identifier, $record_number)
	{
        return $dbase_identifier->delete_record($record_number);
    }

    function dbase_replace_record($dbase_identifier, $record, $record_number)
	{
        return $dbase_identifier->replace_record($record, $record_number);
    }

    function dbase_get_record($dbase_identifier, $record_number)
	{
        return $dbase_identifier->get_record($record_number);
    }

    function dbase_get_record_with_names($dbase_identifier, $record_number)
	{
        return $dbase_identifier->get_record_with_names($record_number);
    }

    function dbase_pack($dbase_identifier)
	{
        return $dbase_identifier->pack();
    }
}