Lots of random cleanups, mostly for native_theme_win.cc:
[chromium-blink-merge.git] / net / http / http_vary_data.h
blobec97956e676884e32718ecb3402d05ea7253c16d
1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef NET_HTTP_HTTP_VARY_DATA_H_
6 #define NET_HTTP_HTTP_VARY_DATA_H_
8 #include "base/md5.h"
9 #include "net/base/net_export.h"
11 class Pickle;
12 class PickleIterator;
14 namespace net {
16 struct HttpRequestInfo;
17 class HttpResponseHeaders;
19 // Used to implement the HTTP/1.1 Vary header. This class contains a MD5 hash
20 // over the request headers indicated by a Vary header.
22 // While RFC 2616 requires strict request header comparisons, it is much
23 // cheaper to store a MD5 sum, which should be sufficient. Storing a hash also
24 // avoids messy privacy issues as some of the request headers could hold
25 // sensitive data (e.g., cookies).
27 // NOTE: This class does not hold onto the contents of the Vary header.
28 // Instead, it relies on the consumer to store that and to supply it again to
29 // the MatchesRequest function for comparing against future HTTP requests.
31 class NET_EXPORT_PRIVATE HttpVaryData {
32 public:
33 HttpVaryData();
35 bool is_valid() const { return is_valid_; }
37 // Initialize from a request and its corresponding response headers.
39 // Returns true if a Vary header was found in the response headers and that
40 // Vary header was not empty and did not contain the '*' value. Upon
41 // success, the object is also marked as valid such that is_valid() will
42 // return true. Otherwise, false is returned to indicate that this object
43 // is marked as invalid.
45 bool Init(const HttpRequestInfo& request_info,
46 const HttpResponseHeaders& response_headers);
48 // Initialize from a pickle that contains data generated by a call to the
49 // vary data's Persist method.
51 // Upon success, true is returned and the object is marked as valid such that
52 // is_valid() will return true. Otherwise, false is returned to indicate
53 // that this object is marked as invalid.
55 bool InitFromPickle(const Pickle& pickle, PickleIterator* pickle_iter);
57 // Call this method to persist the vary data. Illegal to call this on an
58 // invalid object.
59 void Persist(Pickle* pickle) const;
61 // Call this method to test if the given request matches the previous request
62 // with which this vary data corresponds. The |cached_response_headers| must
63 // be the same response headers used to generate this vary data.
64 bool MatchesRequest(const HttpRequestInfo& request_info,
65 const HttpResponseHeaders& cached_response_headers) const;
67 private:
68 // Returns the corresponding request header value.
69 static std::string GetRequestValue(const HttpRequestInfo& request_info,
70 const std::string& request_header);
72 // Append to the MD5 context for the given request header.
73 static void AddField(const HttpRequestInfo& request_info,
74 const std::string& request_header,
75 base::MD5Context* context);
77 // A digested version of the request headers corresponding to the Vary header.
78 base::MD5Digest request_digest_;
80 // True when request_digest_ contains meaningful data.
81 bool is_valid_;
84 } // namespace net
86 #endif // NET_HTTP_HTTP_VARY_DATA_H_