OLD | NEW |
| (Empty) |
1 // Copyright (c) 2011 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. | |
4 | |
5 #ifndef NET_PROXY_DHCP_PROXY_SCRIPT_FETCHER_WIN_H_ | |
6 #define NET_PROXY_DHCP_PROXY_SCRIPT_FETCHER_WIN_H_ | |
7 #pragma once | |
8 | |
9 #include <set> | |
10 #include <string> | |
11 | |
12 #include "base/memory/scoped_ptr.h" | |
13 #include "base/memory/scoped_vector.h" | |
14 #include "base/threading/non_thread_safe.h" | |
15 #include "base/timer.h" | |
16 #include "net/proxy/dhcp_proxy_script_fetcher.h" | |
17 | |
18 namespace net { | |
19 | |
20 class DhcpProxyScriptAdapterFetcher; | |
21 class URLRequestContext; | |
22 | |
23 // Windows-specific implementation. | |
24 class DhcpProxyScriptFetcherWin | |
25 : public DhcpProxyScriptFetcher, | |
26 public base::NonThreadSafe { | |
27 public: | |
28 // Creates a DhcpProxyScriptFetcherWin that issues requests through | |
29 // |url_request_context|. |url_request_context| must remain valid for | |
30 // the lifetime of DhcpProxyScriptFetcherWin. | |
31 explicit DhcpProxyScriptFetcherWin(URLRequestContext* url_request_context); | |
32 virtual ~DhcpProxyScriptFetcherWin(); | |
33 | |
34 // DhcpProxyScriptFetcher implementation. | |
35 int Fetch(string16* utf16_text, CompletionCallback* callback) OVERRIDE; | |
36 void Cancel() OVERRIDE; | |
37 const GURL& GetPacURL() const OVERRIDE; | |
38 std::string GetFetcherName() const OVERRIDE; | |
39 | |
40 // Sets |adapter_names| to contain the name of each network adapter on | |
41 // this machine that has DHCP enabled and is not a loop-back adapter. Returns | |
42 // false on error. | |
43 static bool GetCandidateAdapterNames(std::set<std::string>* adapter_names); | |
44 | |
45 protected: | |
46 // Event/state transition handlers | |
47 void OnFetcherDone(int result); | |
48 void OnWaitTimer(); | |
49 void TransitionToDone(); | |
50 | |
51 // Virtual methods introduced to allow unit testing. | |
52 virtual DhcpProxyScriptAdapterFetcher* ImplCreateAdapterFetcher(); | |
53 virtual bool ImplGetCandidateAdapterNames( | |
54 std::set<std::string>* adapter_names); | |
55 virtual int ImplGetMaxWaitMs(); | |
56 | |
57 // This is the outer state machine for fetching PAC configuration from | |
58 // DHCP. It relies for sub-states on the state machine of the | |
59 // DhcpProxyScriptAdapterFetcher class. | |
60 // | |
61 // The goal of the implementation is to the following work in parallel | |
62 // for all network adapters that are using DHCP: | |
63 // a) Try to get the PAC URL configured in DHCP; | |
64 // b) If one is configured, try to fetch the PAC URL. | |
65 // c) Once this is done for all adapters, or a timeout has passed after | |
66 // it has completed for the fastest adapter, return the PAC file | |
67 // available for the most preferred network adapter, if any. | |
68 // | |
69 // The state machine goes from START->NO_RESULTS when it creates | |
70 // and starts an DhcpProxyScriptAdapterFetcher for each adapter. It goes | |
71 // from NO_RESULTS->SOME_RESULTS when it gets the first result; at this | |
72 // point a wait timer is started. It goes from SOME_RESULTS->DONE in | |
73 // two cases: All results are known, or the wait timer expired. A call | |
74 // to Cancel() will also go straight to DONE from any state. Any | |
75 // way the DONE state is entered, we will at that point cancel any | |
76 // outstanding work and return the best known PAC script or the empty | |
77 // string. | |
78 // | |
79 // The state machine is reset for each Fetch(), a call to which is | |
80 // only valid in states START and DONE, as only one Fetch() is | |
81 // allowed to be outstanding at any given time. | |
82 enum State { | |
83 STATE_START, | |
84 STATE_NO_RESULTS, | |
85 STATE_SOME_RESULTS, | |
86 STATE_DONE, | |
87 }; | |
88 | |
89 // Current state of this state machine. | |
90 State state_; | |
91 | |
92 // Vector, in Windows' network adapter preference order, of | |
93 // DhcpProxyScriptAdapterFetcher objects that are or were attempting | |
94 // to fetch a PAC file based on DHCP configuration. | |
95 typedef ScopedVector<DhcpProxyScriptAdapterFetcher> FetcherVector; | |
96 FetcherVector fetchers_; | |
97 | |
98 // Callback invoked when any fetcher completes. | |
99 CompletionCallbackImpl<DhcpProxyScriptFetcherWin> fetcher_callback_; | |
100 | |
101 // Number of fetchers we are waiting for. | |
102 int num_pending_fetchers_; | |
103 | |
104 // Lets our client know we're done. Not valid in states START or DONE. | |
105 CompletionCallback* client_callback_; | |
106 | |
107 // Pointer to string we will write results to. Not valid in states | |
108 // START and DONE. | |
109 string16* destination_string_; | |
110 | |
111 // PAC URL retrieved from DHCP, if any. Valid only in state STATE_DONE. | |
112 GURL pac_url_; | |
113 | |
114 base::OneShotTimer<DhcpProxyScriptFetcherWin> wait_timer_; | |
115 | |
116 scoped_refptr<URLRequestContext> url_request_context_; | |
117 | |
118 DISALLOW_IMPLICIT_CONSTRUCTORS(DhcpProxyScriptFetcherWin); | |
119 }; | |
120 | |
121 } // namespace net | |
122 | |
123 #endif // NET_PROXY_DHCP_PROXY_SCRIPT_FETCHER_WIN_H_ | |
OLD | NEW |