Support HTTP test-server based net unit tests on Android.

tools/android/forwarder2/host_forwarder_main.cc

Index: tools/android/forwarder2/host_forwarder_main.cc
diff --git a/tools/android/forwarder2/host_forwarder_main.cc b/tools/android/forwarder2/host_forwarder_main.cc
index 6e541894cead6671d1a3e7b97d85a11976bc92f9..dff0c8f42e975da0e7ca4dd67a7cc174cf844d75 100644
--- a/tools/android/forwarder2/host_forwarder_main.cc
+++ b/tools/android/forwarder2/host_forwarder_main.cc
@@ -6,32 +6,49 @@
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 #include <vector>
 #include <string>
 
 #include "base/command_line.h"
+#include "base/eintr_wrapper.h"
+#include "base/file_path.h"
+#include "base/file_util.h"
 #include "base/logging.h"
 #include "base/memory/scoped_vector.h"
+#include "base/safe_strerror_posix.h"
 #include "base/string_number_conversions.h"
 #include "base/string_piece.h"
 #include "base/string_split.h"
+#include "base/string_util.h"
 #include "base/stringprintf.h"
-#include "tools/android/common/daemon.h"
+#include "tools/android/forwarder2/common.h"
+#include "tools/android/forwarder2/daemon.h"
 #include "tools/android/forwarder2/host_controller.h"
 #include "tools/android/forwarder2/pipe_notifier.h"
+#include "tools/android/forwarder2/socket.h"
 
 using base::StringToInt;
-using forwarder2::HostController;
 
+namespace forwarder2 {
 namespace {
 
-const int kDefaultAdbPort = 3000;
+const char kPIDFilePath[] = "/tmp/host_forwarder_pid";
+const char kCommandSocketPath[] = "host_forwarder_command_socket";
+const char kWelcomeMessage[] = "forwarder2";
+const int kBufSize = 256;
 
 // Need to be global to be able to accessed from the signal handler.
-forwarder2::PipeNotifier* g_notifier;
+PipeNotifier* g_notifier;
 
-void KillHandler(int /* unused */) {
+void KillHandler(int signal_number) {
+  if (signal_number != SIGTERM && signal_number != SIGINT) {
+    char buf[kBufSize];
+    snprintf(buf, sizeof(buf), "Ignoring unexpected signal %d.", signal_number);
+    SIGNAL_SAFE_LOG(WARNING, buf);
+    return;
+  }
   static int s_kill_handler_count = 0;
   CHECK(g_notifier);
   // If for some reason the forwarder get stuck in any socket waiting forever,
@@ -42,110 +59,224 @@ void KillHandler(int /* unused */) {
     exit(1);
 }
 
-// Format of arg: <Device port>[:<Forward to port>:<Forward to address>]
-bool ParseForwardArg(const std::string& arg,
-                     int* device_port,
-                     std::string* forward_to_host,
-                     int* forward_to_port) {
-  std::vector<std::string> arg_pieces;
-  base::SplitString(arg, ':', &arg_pieces);
-  if (arg_pieces.size() == 0 || !StringToInt(arg_pieces[0], device_port))
+enum {
+  kConnectSingleTry = 1,
+  kConnectNoIdleTime = 0,
+};
+
+scoped_ptr<Socket> ConnectToDaemon(int tries_count, int idle_time_msec) {
+  for (int i = 0; i < tries_count; ++i) {
+    scoped_ptr<Socket> socket(new Socket());
+    if (!socket->ConnectUnix(kCommandSocketPath, true)) {
+      if (idle_time_msec)
+        usleep(idle_time_msec * 1000);
+      continue;
+    }
+    char buf[sizeof(kWelcomeMessage)];
+    memset(buf, 0, sizeof(buf));
+    if (socket->Read(buf, sizeof(buf)) < 0) {
+      perror("read");
+      continue;
+    }
+    if (strcmp(buf, kWelcomeMessage)) {
+      LOG(ERROR) << "Unexpected message read from daemon: " << buf;
+      break;
+    }
+    return socket.Pass();
+  }
+  return scoped_ptr<Socket>(NULL);
+}
+
+// Format of |command|:
+//   <ADB port>:<Device port>[:<Forward to port>:<Forward to address>].
+bool ParseForwardCommand(const std::string& command,
+                         int* adb_port,
+                         int* device_port,
+                         std::string* forward_to_host,
+                         int* forward_to_port) {
+  std::vector<std::string> command_pieces;
+  base::SplitString(command, ':', &command_pieces);
+
+  if (command_pieces.size() < 2 ||
+      !StringToInt(command_pieces[0], adb_port) ||
+      !StringToInt(command_pieces[1], device_port))
     return false;
 
-  if (arg_pieces.size() > 1) {
-    if (!StringToInt(arg_pieces[1], forward_to_port))
+  if (command_pieces.size() > 2) {
+    if (!StringToInt(command_pieces[2], forward_to_port))
       return false;
-    if (arg_pieces.size() > 2)
-      *forward_to_host = arg_pieces[2];
+    if (command_pieces.size() > 3)
+      *forward_to_host = command_pieces[3];
   } else {
     *forward_to_port = *device_port;
   }
   return true;
 }
 
-}  // namespace
+bool IsForwardCommandValid(const std::string& command) {
+  int adb_port, device_port, forward_to_port;
+  std::string forward_to_host;
+  std::vector<std::string> command_pieces;
+  return ParseForwardCommand(
+      command, &adb_port, &device_port, &forward_to_host, &forward_to_port);
+}
 
-int main(int argc, char** argv) {
-  printf("Host forwarder to handle incoming connections from Android.\n");
-  printf("Like 'adb forward' but in the reverse direction\n");
-
-  CommandLine command_line(argc, argv);
-  bool show_help = tools::HasHelpSwitch(command_line);
-  std::string adb_port_str = command_line.GetSwitchValueASCII("adb_port");
-  int adb_port = kDefaultAdbPort;
-  if (!adb_port_str.empty() && !StringToInt(adb_port_str, &adb_port)) {
-    printf("Could not parse adb port number: %s\n", adb_port_str.c_str());
-    show_help = true;
-  }
-  if (adb_port <= 0) {
-    printf("Invalid adb port number: %s. Adb port must be a "
-           "postivie integer.\n", adb_port_str.c_str());
-    show_help = true;
-  }
-  CommandLine::StringVector forward_args = command_line.GetArgs();
-  if (show_help || forward_args.empty()) {
-    tools::ShowHelp(
-        argv[0],
-        "[--adb_port=<adb port>] "
-        "<Device port>[:<Forward to port>:<Forward to address>] ...",
-        base::StringPrintf(
-            "  <adb port> is the TCP port Adb is configured to forward to."
-            " Default is %d\n"
-            "  <Forward to port> default is <Device port>\n"
-            "  <Forward to address> default is 127.0.0.1.",
-            kDefaultAdbPort).c_str());
-    return 1;
+bool DaemonHandler() {
+  LOG(INFO) << "Starting host process daemon (pid=" << getpid() << ")";
+  DCHECK(!g_notifier);
+  g_notifier = new PipeNotifier();
+
+  const int notifier_fd = g_notifier->receiver_fd();
+  Socket command_socket;
+  if (!command_socket.BindUnix(kCommandSocketPath, true)) {
+    LOG(ERROR) << "Could not bind Unix Domain Socket";
+    return false;
   }
+  command_socket.set_exit_notifier_fd(notifier_fd);
+
+  signal(SIGTERM, KillHandler);
+  signal(SIGINT, KillHandler);
 
-  g_notifier = new forwarder2::PipeNotifier();
   ScopedVector<HostController> controllers;
   int failed_count = 0;
-  for (size_t i = 0; i < forward_args.size(); ++i) {
+
+  for (;;) {
+    Socket client_socket;
+    if (!command_socket.Accept(&client_socket)) {
+      if (command_socket.exited())
+        return true;
+      PError("Accept()");
+      return false;
+    }
+    if (!client_socket.Write(kWelcomeMessage, sizeof(kWelcomeMessage))) {
+      PError("Write()");
+      continue;
+    }
+    char buf[kBufSize];
+    const int bytes_read = client_socket.Read(buf, sizeof(buf));
+    if (bytes_read <= 0) {
+      if (client_socket.exited())
+        break;
+      PError("Read()");
+      ++failed_count;
+    }
+    const std::string command(buf, bytes_read);
+    int adb_port = 0;
     int device_port = 0;
     std::string forward_to_host;
     int forward_to_port = 0;
-    if (ParseForwardArg(forward_args[i],
-                        &device_port,
-                        &forward_to_host,
-                        &forward_to_port)) {
-      scoped_ptr<HostController> host_controller(
-          new HostController(device_port,
-                             forward_to_host,
-                             forward_to_port,
-                             adb_port,
-                             g_notifier->receiver_fd()));
-      if (!host_controller->Connect())
-        continue;
-      host_controller->Start();
-      // Get the current allocated port.
-      device_port = host_controller->device_port();
-      printf("Forwarding device port %d to host %d:%s\n",
-             device_port, forward_to_port, forward_to_host.c_str());
-
-      controllers.push_back(host_controller.release());
-    } else {
-      printf("Couldn't start forwarder server for port spec: %s\n",
-             forward_args[i].c_str());
+    const bool succeeded = ParseForwardCommand(
+        command, &adb_port, &device_port, &forward_to_host, &forward_to_port);
+    if (!succeeded) {
+      ++failed_count;
+      client_socket.WriteString(
+          base::StringPrintf("ERROR: Could not parse forward command '%s'",
+                             command.c_str()));
+      continue;
+    }
+    scoped_ptr<HostController> host_controller(
+        new HostController(device_port, forward_to_host, forward_to_port,
+                           adb_port, notifier_fd));
+    if (!host_controller->Connect()) {
       ++failed_count;
+      client_socket.WriteString("ERROR: Connection to device failed.");
+      continue;
     }
+    // Get the current allocated port.
+    device_port = host_controller->device_port();
+    LOG(INFO) << "Forwarding device port " << device_port << " to host "
+              << forward_to_host << ":" << forward_to_port;
+    if (!client_socket.WriteString(
+        base::StringPrintf("%d:%d", device_port, forward_to_port))) {
+      ++failed_count;
+      continue;
+    }
+    host_controller->Start();
+    controllers.push_back(host_controller.release());
   }
-
-  // Signal handler must be installed after the for loop above where we start
-  // the host_controllers and push_back into the vector. Otherwise a race
-  // condition may occur.
-  signal(SIGTERM, KillHandler);
-  signal(SIGINT, KillHandler);
+  for (int i = 0; i < controllers.size(); ++i)
+    controllers[i]->Join();
 
   if (controllers.size() == 0) {
-    printf("No forwarder servers could be started. Exiting.\n");
-    return failed_count;
+    LOG(ERROR) << "No forwarder servers could be started. Exiting.";
+    return false;
   }
+  return true;
+}
 
-  // TODO(felipeg): We should check if the controllers are really alive before
-  // printing Ready.
-  printf("Host Forwarder Ready.\n");
-  for (int i = 0; i < controllers.size(); ++i)
-    controllers[i]->Join();
+void PrintUsage(const char* program_name) {
+  LOG(ERROR) << program_name << " adb_port:from_port:to_port:to_host\n"
+      "<adb port> is the TCP port Adb is configured to forward to.";
+}
+
+int RunHostForwarder(int argc, char** argv) {
+  if (!CommandLine::Init(argc, argv)) {
+    LOG(ERROR) << "Could not initialize command line";
+    return 1;
+  }
+  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
+  std::string command;
+  int adb_port = 0;
+  if (argc != 2) {
+    PrintUsage(argv[0]);
+    return 1;
+  }
+  if (!strcmp(argv[1], "kill-server")) {
+    command = "kill-server";
+  } else {
+    command = "forward";
+    if (!IsForwardCommandValid(argv[1])) {
+      PrintUsage(argv[0]);
+      return 1;
+    }
+  }
+
+  Daemon daemon(kPIDFilePath);
+
+  if (command == "kill-server")
+    return !daemon.Kill();
+
+  bool is_daemon = false;
+  scoped_ptr<Socket> daemon_socket = ConnectToDaemon(
+      kConnectSingleTry, kConnectNoIdleTime);
+  if (!daemon_socket) {
+    if (!daemon.Spawn(&is_daemon))
+      return 1;
+  }
+
+  if (is_daemon)
+    return !DaemonHandler();
+
+  if (!daemon_socket) {
+    const int kTries = 10;
+    const int kIdleTimeMsec = 10;
+    daemon_socket = ConnectToDaemon(kTries, kIdleTimeMsec);
+    if (!daemon_socket) {
+      LOG(ERROR) << "Could not connect to daemon.";
+      return 1;
+    }
+  }
 
+  // Send the forward command to the daemon.
+  CHECK(daemon_socket->Write(argv[1], strlen(argv[1])));
+  char buf[kBufSize];
+  const int bytes_read = daemon_socket->Read(
+      buf, sizeof(buf) - 1 /* leave space for null terminator */);
+  CHECK_GT(bytes_read, 0);
+  DCHECK(bytes_read < sizeof(buf));
+  buf[bytes_read] = 0;
+  base::StringPiece msg(buf, bytes_read);
+  if (msg.starts_with("ERROR")) {
+    LOG(ERROR) << msg;
+    return 1;
+  }
+  printf("%s\n", buf);
   return 0;
 }
+
+}  // namespace
+}  // namespace forwarder2
+
+int main(int argc, char** argv) {
+  return forwarder2::RunHostForwarder(argc, argv);
+}