使用 PHP 动态压缩 tar.gz 格式的目录

Question

我想使用 PHP 压缩（即时）tar.gz 格式的目录。我知道可以使用exec 或this code（使用ZIP 格式）来完成，但是我的主机不支持exec 并且没有安装PHP 的zip 扩展。

在网上搜索后发现this PHP code：

<?php
// Computes the unsigned Checksum of a file’s header
// to try to ensure valid file
// PRIVATE ACCESS FUNCTION
function __computeUnsignedChecksum($bytestring) {
  for($i=0; $i<512; $i++)
    $unsigned_chksum += ord($bytestring[$i]);
  for($i=0; $i<8; $i++)
    $unsigned_chksum -= ord($bytestring[148 + $i]);
  $unsigned_chksum += ord(" ") * 8;

  return $unsigned_chksum;
}

// Generates a TAR file from the processed data
// PRIVATE ACCESS FUNCTION
function tarSection($Name, $Data, $information=NULL) {
  // Generate the TAR header for this file

  $header .= str_pad($Name,100,chr(0));
  $header .= str_pad("777",7,"0",STR_PAD_LEFT) . chr(0);
  $header .= str_pad(decoct($information["user_id"]),7,"0",STR_PAD_LEFT) . chr(0);
  $header .= str_pad(decoct($information["group_id"]),7,"0",STR_PAD_LEFT) . chr(0);
  $header .= str_pad(decoct(strlen($Data)),11,"0",STR_PAD_LEFT) . chr(0);
  $header .= str_pad(decoct(time(0)),11,"0",STR_PAD_LEFT) . chr(0);
  $header .= str_repeat(" ",8);
  $header .= "0";
  $header .= str_repeat(chr(0),100);
  $header .= str_pad("ustar",6,chr(32));
  $header .= chr(32) . chr(0);
  $header .= str_pad($information["user_name"],32,chr(0));
  $header .= str_pad($information["group_name"],32,chr(0));
  $header .= str_repeat(chr(0),8);
  $header .= str_repeat(chr(0),8);
  $header .= str_repeat(chr(0),155);
  $header .= str_repeat(chr(0),12);

  // Compute header checksum
  $checksum = str_pad(decoct(__computeUnsignedChecksum($header)),6,"0",STR_PAD_LEFT);
  for($i=0; $i<6; $i++) {
    $header[(148 + $i)] = substr($checksum,$i,1);
  }
  $header[154] = chr(0);
  $header[155] = chr(32);

  // Pad file contents to byte count divisible by 512
  $file_contents = str_pad($Data,(ceil(strlen($Data) / 512) * 512),chr(0));

  // Add new tar formatted data to tar file contents
  $tar_file = $header . $file_contents;

  return $tar_file;
}

function targz($Name, $Data) {
  return gzencode(tarSection($Name,$Data),9);
}

header("Content-Disposition: attachment; filename=backup.tar.gz");
header("Content-type: application/x-gzip");

$getfile = file_get_contents("test.txt");

echo targz('test.txt', $getfile);
?>

这确实适用于使用这个的多个文件：

header("Content-Disposition: attachment; filename=backup.tar.gz");
header("Content-type: application/x-gzip");

$getfile = file_get_contents("test.txt");

echo targz('test.txt', $getfile);

$getfile2 = file_get_contents("test2.txt");

echo targz('test2.txt', $getfile2);

backup.tar.gz 现在有 2 个文件（test.txt 和 test2.txt）。

但是如何使用它来下载目录（和子目录）？

我的目录是这样的：

home/
    file1.html
    file2.html
Another_Dir/
    file8.html
    Sub_Dir/
        file19.html

Answer 1

您还需要列出要压缩的目录中的所有文件和目录。有一个递归目录列表函数here。我认为将您的代码与他的代码结合起来即可完成工作。像这样：

header("Content-Disposition: attachment; filename=backup.tar.gz");
header("Content-type: application/x-gzip");

// Your other tar.gz functions...

function compress( $path = '.', $level = 0 ){ 
    $ignore = array( 'cgi-bin', '.', '..' ); 
    $dh = @opendir( $path );

    while( false !== ( $file = readdir( $dh ) ) ){                                   
        if( !in_array( $file, $ignore ) ){
            if( is_dir( "$path/$file" ) ){
                // Go to the subdirs to compress files inside the subdirs
                compress( "$path/$file", ($level+1) );                                           
            } else {
                $getfile = file_get_contents($path. '/' .$file);
                // get the last dir in the $path
                $dirs = array_filter( explode('/', $path) );
                $dir = array_pop($dirs);

                // if we're not in a sub dir just compress the file in root otherwise add it on the subdir...
                if ($level < 1) {
                    echo targz($file, $getfile);
                } else {
                    // add all top level subdirs when $level is > 2
                    for ($i = 0; $i < $level - 1; $i++) {
                        $temp = array_pop($dirs);
                        $dir = $temp.'/'.$dir;
                    }
                    echo targz($dir. '/' .$file, $getfile);
                }
            }                                        
        }                                    
    } 

    closedir( $dh ); 
}

$dir    = 'dir/to/compress';
if (is_file($dir)) {
    // If it's a file path just compress it & push it to output
    $getfile = file_get_contents($dir);
    echo targz(basename($dir), $getfile);
} elseif(is_dir($dir)) {
    return compress($dir);
}

它对我来说很好用。这是我的第一个贡献，希望对您有所帮助..