read a file from a ZIP without diskwrite

darcs-hash:20071210191826-da454-9b88e46e7ab574d605280152905f884cc64abad6.gz

1 files changed, 86 insertions, 0 deletions

diff --git a/inc/ZipLib.class.php b/inc/ZipLib.class.php
index 3b39ad1b6..84164dd4a 100644
--- a/inc/ZipLib.class.php
+++ b/inc/ZipLib.class.php
@@ -349,5 +349,91 @@ class ZipLib
     return ap_mkdir($d);  
  }
  //--CS end
+
+
+ function ExtractStr($zn, $name) {
+   $ok = 0; 
+   $zip = @fopen($zn,'rb');
+   if(!$zip) return(NULL);
+   $cdir = $this->ReadCentralDir($zip,$zn);
+   $pos_entry = $cdir['offset'];
+
+   for ($i=0; $i<$cdir['entries']; $i++)
+   {
+     @fseek($zip, $pos_entry);
+     $header = $this->ReadCentralFileHeaders($zip);
+     $header['index'] = $i; 
+     $pos_entry = ftell($zip);
+     @rewind($zip); 
+     fseek($zip, $header['offset']);
+     if ($name == $header['stored_filename'] || $name == $header['filename']) {
+       $str = $this->ExtractStrFile($header, $zip);
+       fclose($zip);
+       return $str;
+     }
+      
+   }
+   fclose($zip);
+   return null;
+ }
+  
+  function ExtractStrFile($header,$zip) {
+    $hdr = $this->readfileheader($zip);
+    $binary_data = '';
+    if (!($header['external']==0x41FF0010) && !($header['external']==16))
+      {
+	if ($header['compression']==0)
+	  { 
+	    while ($size != 0)
+	      {
+		$read_size = ($size < 2048 ? $size : 2048);
+		$buffer = fread($zip, $read_size);
+		$binary_data .= pack('a'.$read_size, $buffer);
+		$size -= $read_size;
+	      }
+	    return $binary_data;
+	  } else {
+	    $size = $header['compressed_size'];
+	    if ($size == 0) {
+	      return '';
+	    }
+	    //Just in case
+	    if ($size > ($this->_ret_bytes(ini_get('memory_limit'))/2)) {
+	      die("Compressed file is to huge to be uncompress in memory.");
+	    }
+	    while ($size != 0)
+	      {
+		$read_size = ($size < 2048 ? $size : 2048);
+		$buffer = fread($zip, $read_size);
+		$binary_data .= pack('a'.$read_size, $buffer);
+		$size -= $read_size;
+	      }
+	    $str = gzinflate($binary_data, $header['size']);
+	    if ($header['crc'] == crc32($str)) {
+	      return $str;
+	    } else {
+	      die("Crc Error");
+	    }
+	  }
+      }
+    return NULL;
+  }
+  
+ function _ret_bytes($val) {
+   $val = trim($val);
+   $last = $val{strlen($val)-1};
+   switch($last) {
+   case 'k':
+   case 'K':
+     return (int) $val * 1024;
+     break;
+   case 'm':
+   case 'M':
+     return (int) $val * 1048576;
+     break;
+   default:
+     return $val;
+   }
+ }
 }