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diff --git a/chromium/net/filter/gzip_header.h b/chromium/net/filter/gzip_header.h
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+++ b/chromium/net/filter/gzip_header.h
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+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// The GZipHeader class allows you to parse a gzip header, such as you
+// might find at the beginning of a file compressed by gzip (ie, a .gz
+// file), or at the beginning of an HTTP response that uses a gzip
+// Content-Encoding. See RFC 1952 for the specification for the gzip
+// header.
+//
+// The model is that you call ReadMore() for each chunk of bytes
+// you've read from a file or socket.
+//
+
+#ifndef NET_FILTER_GZIP_HEADER_H_
+#define NET_FILTER_GZIP_HEADER_H_
+
+#include "base/basictypes.h"
+
+namespace net {
+
+class GZipHeader {
+ public:
+  enum Status {
+    INCOMPLETE_HEADER,    // don't have all the bits yet...
+    COMPLETE_HEADER,      // complete, valid header
+    INVALID_HEADER,       // found something invalid in the header
+  };
+
+  GZipHeader();
+  ~GZipHeader();
+
+  // Wipe the slate clean and start from scratch.
+  void Reset();
+
+  // Attempt to parse the given buffer as the next installment of
+  // bytes from a gzip header. If the bytes we've seen so far do not
+  // yet constitute a complete gzip header, return
+  // INCOMPLETE_HEADER. If these bytes do not constitute a *valid*
+  // gzip header, return INVALID_HEADER. When we've seen a complete
+  // gzip header, return COMPLETE_HEADER and set the pointer pointed
+  // to by header_end to the first byte beyond the gzip header.
+  Status ReadMore(const char* inbuf,
+                  int inbuf_len,
+                  const char** header_end);
+ private:
+  enum {                       // flags (see RFC)
+    FLAG_FTEXT        = 0x01,  // bit 0 set: file probably ascii text
+    FLAG_FHCRC        = 0x02,  // bit 1 set: header CRC present
+    FLAG_FEXTRA       = 0x04,  // bit 2 set: extra field present
+    FLAG_FNAME        = 0x08,  // bit 3 set: original file name present
+    FLAG_FCOMMENT     = 0x10,  // bit 4 set: file comment present
+    FLAG_RESERVED     = 0xE0,  // bits 5..7: reserved
+  };
+
+  enum State {
+    // The first 10 bytes are the fixed-size header:
+    IN_HEADER_ID1,
+    IN_HEADER_ID2,
+    IN_HEADER_CM,
+    IN_HEADER_FLG,
+    IN_HEADER_MTIME_BYTE_0,
+    IN_HEADER_MTIME_BYTE_1,
+    IN_HEADER_MTIME_BYTE_2,
+    IN_HEADER_MTIME_BYTE_3,
+    IN_HEADER_XFL,
+    IN_HEADER_OS,
+
+    IN_XLEN_BYTE_0,
+    IN_XLEN_BYTE_1,
+    IN_FEXTRA,
+
+    IN_FNAME,
+
+    IN_FCOMMENT,
+
+    IN_FHCRC_BYTE_0,
+    IN_FHCRC_BYTE_1,
+
+    IN_DONE,
+  };
+
+  static const uint8 magic[];  // gzip magic header
+
+  int    state_;  // our current State in the parsing FSM: an int so we can ++
+  uint8  flags_;         // the flags byte of the header ("FLG" in the RFC)
+  uint16 extra_length_;  // how much of the "extra field" we have yet to read
+
+  DISALLOW_COPY_AND_ASSIGN(GZipHeader);
+};
+
+}  // namespace net
+
+#endif  // NET_FILTER_GZIP_HEADER_H_