local_test_server_win.cc revision 116680a4aac90f2aa7413d9095a592090648e557 
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.
4
5#include "net/test/spawned_test_server/local_test_server.h"
6
7#include <windows.h>
8#include <wincrypt.h>
9
10#include "base/base_paths.h"
11#include "base/bind.h"
12#include "base/command_line.h"
13#include "base/environment.h"
14#include "base/files/file_path.h"
15#include "base/message_loop/message_loop.h"
16#include "base/path_service.h"
17#include "base/process/launch.h"
18#include "base/strings/string_number_conversions.h"
19#include "base/strings/string_util.h"
20#include "base/strings/utf_string_conversions.h"
21#include "base/test/test_timeouts.h"
22#include "base/threading/thread.h"
23#include "base/win/scoped_handle.h"
24#include "net/test/python_utils.h"
25
26#pragma comment(lib, "crypt32.lib")
27
28namespace {
29
30// Writes |size| bytes to |handle| and sets |*unblocked| to true.
31// Used as a crude timeout mechanism by ReadData().
32void UnblockPipe(HANDLE handle, DWORD size, bool* unblocked) {
33  std::string unblock_data(size, '\0');
34  // Unblock the ReadFile in LocalTestServer::WaitToStart by writing to the
35  // pipe. Make sure the call succeeded, otherwise we are very likely to hang.
36  DWORD bytes_written = 0;
37  LOG(WARNING) << "Timeout reached; unblocking pipe by writing "
38               << size << " bytes";
39  CHECK(WriteFile(handle, unblock_data.data(), size, &bytes_written,
40                  NULL));
41  CHECK_EQ(size, bytes_written);
42  *unblocked = true;
43}
44
45// Given a file handle, reads into |buffer| until |bytes_max| bytes
46// has been read or an error has been encountered.  Returns
47// true if the read was successful.
48bool ReadData(HANDLE read_fd, HANDLE write_fd,
49              DWORD bytes_max, uint8* buffer) {
50  base::Thread thread("test_server_watcher");
51  if (!thread.Start())
52    return false;
53
54  // Prepare a timeout in case the server fails to start.
55  bool unblocked = false;
56  thread.message_loop()->PostDelayedTask(
57      FROM_HERE, base::Bind(UnblockPipe, write_fd, bytes_max, &unblocked),
58      TestTimeouts::action_max_timeout());
59
60  DWORD bytes_read = 0;
61  while (bytes_read < bytes_max) {
62    DWORD num_bytes;
63    if (!ReadFile(read_fd, buffer + bytes_read, bytes_max - bytes_read,
64                  &num_bytes, NULL)) {
65      PLOG(ERROR) << "ReadFile failed";
66      return false;
67    }
68    if (num_bytes <= 0) {
69      LOG(ERROR) << "ReadFile returned invalid byte count: " << num_bytes;
70      return false;
71    }
72    bytes_read += num_bytes;
73  }
74
75  thread.Stop();
76  // If the timeout kicked in, abort.
77  if (unblocked) {
78    LOG(ERROR) << "Timeout exceeded for ReadData";
79    return false;
80  }
81
82  return true;
83}
84
85// Class that sets up a temporary path that includes the supplied path
86// at the end.
87//
88// TODO(bratell): By making this more generic we can possibly reuse
89//                it at other places such as
90//                chrome/common/multi_process_lock_unittest.cc.
91class ScopedPath {
92 public:
93  // Constructor which sets up the environment to include the path to
94  // |path_to_add|.
95  explicit ScopedPath(const base::FilePath& path_to_add);
96
97  // Destructor that restores the path that were active when the
98  // object was constructed.
99  ~ScopedPath();
100
101 private:
102  // The PATH environment variable before it was changed or an empty
103  // string if there was no PATH environment variable.
104  std::string old_path_;
105
106  // The helper object that allows us to read and set environment
107  // variables more easily.
108  scoped_ptr<base::Environment> environment_;
109
110  // A flag saying if we have actually modified the environment.
111  bool path_modified_;
112
113  DISALLOW_COPY_AND_ASSIGN(ScopedPath);
114};
115
116ScopedPath::ScopedPath(const base::FilePath& path_to_add)
117    : environment_(base::Environment::Create()),
118      path_modified_(false) {
119  environment_->GetVar("PATH", &old_path_);
120
121  std::string new_value = old_path_;
122  if (!new_value.empty())
123    new_value += ";";
124
125  new_value += base::WideToUTF8(path_to_add.value());
126
127  path_modified_ = environment_->SetVar("PATH", new_value);
128}
129
130ScopedPath::~ScopedPath() {
131  if (!path_modified_)
132    return;
133  if (old_path_.empty())
134    environment_->UnSetVar("PATH");
135  else
136    environment_->SetVar("PATH", old_path_);
137}
138
139}  // namespace
140
141namespace net {
142
143bool LocalTestServer::LaunchPython(const base::FilePath& testserver_path) {
144  base::CommandLine python_command(base::CommandLine::NO_PROGRAM);
145  if (!GetPythonCommand(&python_command))
146    return false;
147
148  python_command.AppendArgPath(testserver_path);
149  if (!AddCommandLineArguments(&python_command))
150    return false;
151
152  HANDLE child_read = NULL;
153  HANDLE child_write = NULL;
154  if (!CreatePipe(&child_read, &child_write, NULL, 0)) {
155    PLOG(ERROR) << "Failed to create pipe";
156    return false;
157  }
158  child_read_fd_.Set(child_read);
159  child_write_fd_.Set(child_write);
160
161  // Have the child inherit the write half.
162  if (!SetHandleInformation(child_write, HANDLE_FLAG_INHERIT,
163                            HANDLE_FLAG_INHERIT)) {
164    PLOG(ERROR) << "Failed to enable pipe inheritance";
165    return false;
166  }
167
168  // Pass the handle on the command-line. Although HANDLE is a
169  // pointer, truncating it on 64-bit machines is okay. See
170  // http://msdn.microsoft.com/en-us/library/aa384203.aspx
171  //
172  // "64-bit versions of Windows use 32-bit handles for
173  // interoperability. When sharing a handle between 32-bit and 64-bit
174  // applications, only the lower 32 bits are significant, so it is
175  // safe to truncate the handle (when passing it from 64-bit to
176  // 32-bit) or sign-extend the handle (when passing it from 32-bit to
177  // 64-bit)."
178  python_command.AppendArg("--startup-pipe=" +
179      base::IntToString(reinterpret_cast<uintptr_t>(child_write)));
180
181  base::LaunchOptions launch_options;
182  launch_options.inherit_handles = true;
183  if (!base::LaunchProcess(python_command, launch_options, &process_handle_)) {
184    LOG(ERROR) << "Failed to launch " << python_command.GetCommandLineString();
185    return false;
186  }
187
188  return true;
189}
190
191bool LocalTestServer::WaitToStart() {
192  base::win::ScopedHandle read_fd(child_read_fd_.Take());
193  base::win::ScopedHandle write_fd(child_write_fd_.Take());
194
195  uint32 server_data_len = 0;
196  if (!ReadData(read_fd.Get(), write_fd.Get(), sizeof(server_data_len),
197                reinterpret_cast<uint8*>(&server_data_len))) {
198    LOG(ERROR) << "Could not read server_data_len";
199    return false;
200  }
201  std::string server_data(server_data_len, '\0');
202  if (!ReadData(read_fd.Get(), write_fd.Get(), server_data_len,
203                reinterpret_cast<uint8*>(&server_data[0]))) {
204    LOG(ERROR) << "Could not read server_data (" << server_data_len
205               << " bytes)";
206    return false;
207  }
208
209  if (!ParseServerData(server_data)) {
210    LOG(ERROR) << "Could not parse server_data: " << server_data;
211    return false;
212  }
213
214  return true;
215}
216
217}  // namespace net
218
219