如何解码/膨胀分块的gzip字符串？

Question

在PHP中进行gzip deflate请求后,我收到了偏移块中的缩减字符串,如下所示

示例缩短为显示格式:

00001B4E
¾”kŒj…Øæ’ìÑ«F1ìÊ`+ƒQì¹UÜjùJƒZ\µy¡ÓUžGr‡J&=KLËÙÍ~=ÍkR
0000102F
ñÞœÞôΑüo[¾”+’Ñ8#à»0±R-4VÕ’n›êˆÍ.MCŽ…ÏÖr¿3M—èßñ°r¡\+
00000000

因为分块格式,我无法膨胀.用Hex编辑器手动删除偏移并读取gzip存档后,我可以确认数据没有损坏.我想知道是否有一个正确的方法来解析这个分块的gzip缩减响应到一个可读的字符串？

我可能能够将这些偏移分开并将数据连接在一起以调用gzinflate,但似乎必须有一种更简单的方法.

Answer 1

缩小响应的适当方法大致如下:

initialise string to hold result
for each chunk {
  check that the stated chunk length equals the string length of the chunk
  append the chunk data to the result variable
}

这是一个方便的PHP函数为你做(固定):

function unchunk_string ($str) {

  // A string to hold the result
  $result = '';

  // Split input by CRLF
  $parts = explode("\r\n", $str);

  // These vars track the current chunk
  $chunkLen = 0;
  $thisChunk = '';

  // Loop the data
  while (($part = array_shift($parts)) !== NULL) {
    if ($chunkLen) {
      // Add the data to the string
      // Don't forget, the data might contain a literal CRLF
      $thisChunk .= $part."\r\n";
      if (strlen($thisChunk) == $chunkLen) {
        // Chunk is complete
        $result .= $thisChunk;
        $chunkLen = 0;
        $thisChunk = '';
      } else if (strlen($thisChunk) == $chunkLen + 2) {
        // Chunk is complete, remove trailing CRLF
        $result .= substr($thisChunk, 0, -2);
        $chunkLen = 0;
        $thisChunk = '';
      } else if (strlen($thisChunk) > $chunkLen) {
        // Data is malformed
        return FALSE;
      }
    } else {
      // If we are not in a chunk, get length of the new one
      if ($part === '') continue;
      if (!$chunkLen = hexdec($part)) break;
    }
  }

  // Return the decoded data of FALSE if it is incomplete
  return ($chunkLen) ? FALSE : $result;

}