Adds support for the DHCP portion of the WPAD (proxy auto-discovery) protocol.

This is Windows-only for now, and is disabled by default.  Start
Chrome with the flag --enable-dhcp-wpad to enable the feature.  See
discussion in comment on DhcpProxyScriptFetcherFactory for why this
needs to be done in a per-platform way rather than cross-platform.
The code is factored so that adding other platform implementations
will be straight forward.

Most of the implementation is stand-alone and extends the
ScriptProxyFetcher class hierarchy (and makes its interface slightly
more generic).  The integration point into existing code is in
InitProxyResolver, which previously handled fallback from DNS
auto-detect to custom PAC URL and now does fallback from DHCP to DNS
to custom PAC URL.

BUG=18575
TEST=net_unittests has good coverage for the new and changed code, but
manual tests on a network with a PAC URL configured in DHCP are also
needed.

Review URL: http://codereview.chromium.org/6831025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@85646 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 55 insertions, 0 deletions

diff --git a/net/proxy/mock_proxy_script_fetcher.cc b/net/proxy/mock_proxy_script_fetcher.cc
new file mode 100644
index 0000000..3e9b601
--- /dev/null
+++ b/net/proxy/mock_proxy_script_fetcher.cc
@@ -0,0 +1,55 @@
+// Copyright (c) 2011 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.
+
+#include "net/proxy/mock_proxy_script_fetcher.h"
+
+#include "base/logging.h"
+#include "base/string16.h"
+#include "base/utf_string_conversions.h"
+#include "net/base/net_errors.h"
+
+namespace net {
+
+MockProxyScriptFetcher::MockProxyScriptFetcher()
+    : pending_request_callback_(NULL), pending_request_text_(NULL) {
+}
+
+// ProxyScriptFetcher implementation.
+int MockProxyScriptFetcher::Fetch(const GURL& url,
+                                  string16* text,
+                                  CompletionCallback* callback) {
+  DCHECK(!has_pending_request());
+
+  // Save the caller's information, and have them wait.
+  pending_request_url_ = url;
+  pending_request_callback_ = callback;
+  pending_request_text_ = text;
+  return ERR_IO_PENDING;
+}
+
+void MockProxyScriptFetcher::NotifyFetchCompletion(
+    int result, const std::string& ascii_text) {
+  DCHECK(has_pending_request());
+  *pending_request_text_ = ASCIIToUTF16(ascii_text);
+  CompletionCallback* callback = pending_request_callback_;
+  pending_request_callback_ = NULL;
+  callback->Run(result);
+}
+
+void MockProxyScriptFetcher::Cancel() {
+}
+
+URLRequestContext* MockProxyScriptFetcher::GetRequestContext() const {
+  return NULL;
+}
+
+const GURL& MockProxyScriptFetcher::pending_request_url() const {
+  return pending_request_url_;
+}
+
+bool MockProxyScriptFetcher::has_pending_request() const {
+  return pending_request_callback_ != NULL;
+}
+
+}  // namespace net