net/test/spawned_test_server/local_test_server_posix.cc

   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 <poll.h>
   8
   9 #include <vector>
  10
  11 #include "base/command_line.h"
  12 #include "base/files/file_util.h"
  13 #include "base/files/scoped_file.h"
  14 #include "base/logging.h"
  15 #include "base/process/kill.h"
  16 #include "base/process/launch.h"
  17 #include "base/process/process_iterator.h"
  18 #include "base/strings/string_number_conversions.h"
  19 #include "base/strings/string_util.h"
  20 #include "base/test/test_timeouts.h"
  21 #include "net/test/python_utils.h"
  22
  23 namespace {
  24
  25 // Helper class used to detect and kill orphaned python test server processes.
  26 // Checks if the command line of a process contains |path_string| (the path
  27 // from which the test server was launched) and |port_string| (the port used by
  28 // the test server), and if the parent pid of the process is 1 (indicating that
  29 // it is an orphaned process).
  30 class OrphanedTestServerFilter : public base::ProcessFilter {
  31  public:
  32   OrphanedTestServerFilter(
  33       const std::string& path_string, const std::string& port_string)
  34       : path_string_(path_string),
  35         port_string_(port_string) {}
  36
  37   bool Includes(const base::ProcessEntry& entry) const override {
  38     if (entry.parent_pid() != 1)
  39       return false;
  40     bool found_path_string = false;
  41     bool found_port_string = false;
  42     for (std::vector<std::string>::const_iterator it =
  43          entry.cmd_line_args().begin();
  44          it != entry.cmd_line_args().end();
  45          ++it) {
  46       if (it->find(path_string_) != std::string::npos)
  47         found_path_string = true;
  48       if (it->find(port_string_) != std::string::npos)
  49         found_port_string = true;
  50     }
  51     return found_path_string && found_port_string;
  52   }
  53
  54  private:
  55   std::string path_string_;
  56   std::string port_string_;
  57   DISALLOW_COPY_AND_ASSIGN(OrphanedTestServerFilter);
  58 };
  59
  60 // Given a file descriptor, reads into |buffer| until |bytes_max|
  61 // bytes has been read or an error has been encountered.  Returns true
  62 // if the read was successful.  |remaining_time| is used as a timeout.
  63 bool ReadData(int fd, ssize_t bytes_max, uint8* buffer,
  64               base::TimeDelta* remaining_time) {
  65   ssize_t bytes_read = 0;
  66   base::TimeTicks previous_time = base::TimeTicks::Now();
  67   while (bytes_read < bytes_max) {
  68     struct pollfd poll_fds[1];
  69
  70     poll_fds[0].fd = fd;
  71     poll_fds[0].events = POLLIN | POLLPRI;
  72     poll_fds[0].revents = 0;
  73
  74     int rv = HANDLE_EINTR(poll(poll_fds, 1,
  75                                remaining_time->InMilliseconds()));
  76     if (rv == 0) {
  77       LOG(ERROR) << "poll() timed out; bytes_read=" << bytes_read;
  78       return false;
  79     } else if (rv < 0) {
  80       PLOG(ERROR) << "poll() failed for child file descriptor; bytes_read="
  81                   << bytes_read;
  82       return false;
  83     }
  84
  85     base::TimeTicks current_time = base::TimeTicks::Now();
  86     base::TimeDelta elapsed_time_cycle = current_time - previous_time;
  87     DCHECK_GE(elapsed_time_cycle.InMilliseconds(), 0);
  88     *remaining_time -= elapsed_time_cycle;
  89     previous_time = current_time;
  90
  91     ssize_t num_bytes = HANDLE_EINTR(read(fd, buffer + bytes_read,
  92                                           bytes_max - bytes_read));
  93     if (num_bytes <= 0)
  94       return false;
  95     bytes_read += num_bytes;
  96   }
  97   return true;
  98 }
  99
 100 }  // namespace
 101
 102 namespace net {
 103
 104 bool LocalTestServer::LaunchPython(const base::FilePath& testserver_path) {
 105   // Log is useful in the event you want to run a nearby script (e.g. a test) in
 106   // the same environment as the TestServer.
 107   VLOG(1) << "LaunchPython called with PYTHONPATH = " << getenv(kPythonPathEnv);
 108
 109   base::CommandLine python_command(base::CommandLine::NO_PROGRAM);
 110   if (!GetPythonCommand(&python_command))
 111     return false;
 112
 113   python_command.AppendArgPath(testserver_path);
 114   if (!AddCommandLineArguments(&python_command))
 115     return false;
 116
 117   int pipefd[2];
 118   if (pipe(pipefd) != 0) {
 119     PLOG(ERROR) << "Could not create pipe.";
 120     return false;
 121   }
 122
 123   // Save the read half. The write half is sent to the child.
 124   child_fd_.reset(pipefd[0]);
 125   base::ScopedFD write_closer(pipefd[1]);
 126   base::FileHandleMappingVector map_write_fd;
 127   map_write_fd.push_back(std::make_pair(pipefd[1], pipefd[1]));
 128
 129   python_command.AppendArg("--startup-pipe=" + base::IntToString(pipefd[1]));
 130
 131   // Try to kill any orphaned testserver processes that may be running.
 132   OrphanedTestServerFilter filter(testserver_path.value(),
 133                                   base::IntToString(GetPort()));
 134   if (!base::KillProcesses("python", -1, &filter)) {
 135     LOG(WARNING) << "Failed to clean up older orphaned testserver instances.";
 136   }
 137
 138   // Launch a new testserver process.
 139   base::LaunchOptions options;
 140
 141   options.fds_to_remap = &map_write_fd;
 142   process_ = base::LaunchProcess(python_command, options);
 143   if (!process_.IsValid()) {
 144     LOG(ERROR) << "Failed to launch " << python_command.GetCommandLineString();
 145     return false;
 146   }
 147
 148   return true;
 149 }
 150
 151 bool LocalTestServer::WaitToStart() {
 152   base::ScopedFD our_fd(child_fd_.release());
 153
 154   base::TimeDelta remaining_time = TestTimeouts::action_timeout();
 155
 156   uint32 server_data_len = 0;
 157   if (!ReadData(our_fd.get(), sizeof(server_data_len),
 158                 reinterpret_cast<uint8*>(&server_data_len),
 159                 &remaining_time)) {
 160     LOG(ERROR) << "Could not read server_data_len";
 161     return false;
 162   }
 163   std::string server_data(server_data_len, '\0');
 164   if (!ReadData(our_fd.get(), server_data_len,
 165                 reinterpret_cast<uint8*>(&server_data[0]),
 166                 &remaining_time)) {
 167     LOG(ERROR) << "Could not read server_data (" << server_data_len
 168                << " bytes)";
 169     return false;
 170   }
 171
 172   if (!ParseServerData(server_data)) {
 173     LOG(ERROR) << "Could not parse server_data: " << server_data;
 174     return false;
 175   }
 176
 177   return true;
 178 }
 179
 180 }  // namespace net