2 * Copyright (c) 2014 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
19 #include "daemon-private.h"
22 #include "poll-loop.h"
25 VLOG_DEFINE_THIS_MODULE(daemon_windows);
27 static bool service_create; /* Was --service specified? */
28 static bool service_started; /* Have we dispatched service to start? */
30 /* --service-monitor: Should the service be restarted if it dies
34 bool detach; /* Was --detach specified? */
35 static bool detached; /* Running as the child process. */
36 static HANDLE write_handle; /* End of pipe to write to parent. */
38 char *pidfile; /* --pidfile: Name of pidfile (null if none). */
39 static FILE *filep_pidfile; /* File pointer to access the pidfile. */
41 /* Handle to the Services Manager and the created service. */
42 static SC_HANDLE manager, service;
44 /* Handle to the status information structure for the current service. */
45 static SERVICE_STATUS_HANDLE hstatus;
47 /* Hold the service's current status. */
48 static SERVICE_STATUS service_status;
50 /* Handle to an event object used to wakeup from poll_block(). */
53 /* Hold the arguments sent to the main function. */
55 static char ***sargvp;
57 static void check_service(void);
58 static void handle_scm_callback(void);
59 static void init_service_status(void);
60 static void set_config_failure_actions(void);
62 static bool detach_process(int argc, char *argv[]);
64 extern int main(int argc, char *argv[]);
70 "\nService options:\n"
71 " --service run in background as a service.\n"
72 " --service-monitor restart the service in case of an "
73 "unexpected failure. \n",
74 ovs_rundir(), program_name);
77 /* Registers the call-back and configures the actions in case of a failure
78 * with the Windows services manager. */
80 service_start(int *argcp, char **argvp[])
85 SERVICE_TABLE_ENTRY service_table[] = {
86 {(LPTSTR)program_name, (LPSERVICE_MAIN_FUNCTION)main},
90 /* If one of the command line option is "--detach", we create
91 * a new process in case of parent, wait for child to start and exit.
92 * In case of the child, we just return. We should not be creating a
93 * service in either case. */
94 if (detach_process(argc, argv)) {
98 /* 'service_started' is 'false' when service_start() is called the first
99 * time. It is 'true', when it is called the second time by the Windows
100 * services manager. */
101 if (service_started) {
102 init_service_status();
104 wevent = CreateEvent(NULL, TRUE, FALSE, NULL);
106 char *msg_buf = ovs_lasterror_to_string();
107 VLOG_FATAL("Failed to create a event (%s).", msg_buf);
110 poll_fd_wait_event(0, wevent, POLLIN);
112 /* Register the control handler. This function is called by the service
113 * manager to stop the service. */
114 hstatus = RegisterServiceCtrlHandler(program_name,
115 (LPHANDLER_FUNCTION)control_handler);
117 char *msg_buf = ovs_lasterror_to_string();
118 VLOG_FATAL("Failed to register the service control handler (%s).",
123 set_config_failure_actions();
126 /* When the service control manager does the call back, it does not
127 * send the same arguments as sent to the main function during the
128 * service start. So, use the arguments passed over during the first
133 /* XXX: Windows implementation cannot have a unixctl commands in the
134 * traditional sense of unix domain sockets. If an implementation is
135 * done that involves 'unixctl' vlog commands the following call is
136 * needed to make sure that the unixctl commands for vlog get
137 * registered in a daemon, even before the first log message. */
143 assert_single_threaded();
145 /* A reference to arguments passed to the main function the first time.
146 * We need it after the call-back from service control manager. */
150 /* We are only interested in the '--service' and '--service-monitor'
151 * options before the call-back from the service control manager. */
152 for (i = 0; i < argc; i ++) {
153 if (!strcmp(argv[i], "--service")) {
154 service_create = true;
155 } else if (!strcmp(argv[i], "--service-monitor")) {
160 /* If '--service' is not a command line option, run in foreground. */
161 if (!service_create) {
165 /* If we have been configured to run as a service, then that service
166 * should already have been created either manually or through a start up
170 service_started = true;
172 /* StartServiceCtrlDispatcher blocks and returns after the service is
174 if (!StartServiceCtrlDispatcher(service_table)) {
175 char *msg_buf = ovs_lasterror_to_string();
176 VLOG_FATAL("Failed at StartServiceCtrlDispatcher (%s)", msg_buf);
181 /* This function is registered with the Windows services manager through
182 * a call to RegisterServiceCtrlHandler() and will be called by the Windows
183 * services manager asynchronously to stop the service. */
185 control_handler(DWORD request)
188 case SERVICE_CONTROL_STOP:
189 case SERVICE_CONTROL_SHUTDOWN:
190 service_status.dwCurrentState = SERVICE_STOPPED;
191 service_status.dwWin32ExitCode = NO_ERROR;
200 /* Return 'true' if the Windows services manager has called the
201 * control_handler() and asked the program to terminate. */
203 should_service_stop(void)
205 if (service_started) {
206 if (service_status.dwCurrentState != SERVICE_RUNNING) {
209 poll_fd_wait_event(0, wevent, POLLIN);
215 /* Set the service as stopped. The control manager will terminate the
216 * service soon after this call. Hence, this should ideally be the last
217 * call before termination. */
224 service_status.dwCurrentState = SERVICE_STOPPED;
225 service_status.dwWin32ExitCode = NO_ERROR;
226 SetServiceStatus(hstatus, &service_status);
229 /* Call this function to signal that the daemon is ready. init_service()
230 * or control_handler() has already initalized/set the
231 * service_status.dwCurrentState .*/
233 service_complete(void)
236 SetServiceStatus(hstatus, &service_status);
240 /* Check whether 'program_name' has been created as a service. */
244 /* Establish a connection to the local service control manager. */
245 manager = OpenSCManager(NULL, NULL, SC_MANAGER_ENUMERATE_SERVICE);
247 char *msg_buf = ovs_lasterror_to_string();
248 VLOG_FATAL("Failed to open the service control manager (%s).",
252 service = OpenService(manager, program_name, SERVICE_ALL_ACCESS);
254 char *msg_buf = ovs_lasterror_to_string();
255 VLOG_FATAL("Failed to open service (%s).", msg_buf);
259 /* Service status of a service can be checked asynchronously through
260 * tools like 'sc' or through Windows services manager and is set
261 * through a call to SetServiceStatus(). */
263 init_service_status()
265 /* The service runs in its own process. */
266 service_status.dwServiceType = SERVICE_WIN32_OWN_PROCESS;
268 /* The control codes the service accepts. */
269 service_status.dwControlsAccepted = SERVICE_ACCEPT_STOP |
270 SERVICE_ACCEPT_SHUTDOWN;
272 /* Initialize the current state as SERVICE_RUNNING. */
273 service_status.dwCurrentState = SERVICE_RUNNING;
275 /* The exit code to indicate if there was an error. */
276 service_status.dwWin32ExitCode = NO_ERROR;
278 /* The checkpoint value the service increments periodically. Set as 0
279 * as we do not plan to periodically increment the value. */
280 service_status.dwCheckPoint = 0;
282 /* The estimated time required for the stop operation in ms. */
283 service_status.dwWaitHint = 1000;
286 /* In case of an unexpected termination, configure the action to be
289 set_config_failure_actions()
291 /* In case of a failure, restart the process the first two times
292 * After 'dwResetPeriod', the failure count is reset. */
293 SC_ACTION fail_action[3] = {
294 {SC_ACTION_RESTART, 0},
295 {SC_ACTION_RESTART, 0},
298 SERVICE_FAILURE_ACTIONS service_fail_action;
300 /* Reset failure count after (in seconds). */
301 service_fail_action.dwResetPeriod = 10;
303 /* Reboot message. */
304 service_fail_action.lpRebootMsg = NULL;
306 /* The command line of the process. */
307 service_fail_action.lpCommand = NULL;
309 /* Number of elements in 'fail_actions'. */
310 service_fail_action.cActions = sizeof(fail_action)/sizeof(fail_action[0]);
312 /* A pointer to an array of SC_ACTION structures. */
313 service_fail_action.lpsaActions = fail_action;
315 if (!ChangeServiceConfig2(service, SERVICE_CONFIG_FAILURE_ACTIONS,
316 &service_fail_action)) {
317 char *msg_buf = ovs_lasterror_to_string();
318 VLOG_FATAL("Failed to configure service fail actions (%s).", msg_buf);
322 /* When a daemon is passed the --detach option, we create a new
323 * process and pass an additional non-documented option called --pipe-handle.
324 * Through this option, the parent passes one end of a pipe handle. */
326 set_pipe_handle(const char *pipe_handle)
328 write_handle = (HANDLE) atoi(pipe_handle);
331 /* If one of the command line option is "--detach", creates
332 * a new process in case of parent, waits for child to start and exits.
333 * In case of the child, returns. */
335 detach_process(int argc, char *argv[])
337 SECURITY_ATTRIBUTES sa;
339 PROCESS_INFORMATION pi;
340 HANDLE read_pipe, write_pipe;
345 /* We are only interested in the '--detach' and '--pipe-handle'. */
346 for (i = 0; i < argc; i ++) {
347 if (!strcmp(argv[i], "--detach")) {
349 } else if (!strncmp(argv[i], "--pipe-handle", 13)) {
350 /* If running as a child, return. */
356 /* Nothing to do if the option --detach is not set. */
361 /* Set the security attribute such that a process created will
362 * inherit the pipe handles. */
363 sa.nLength = sizeof(sa);
364 sa.lpSecurityDescriptor = NULL;
365 sa.bInheritHandle = TRUE;
367 /* Create an anonymous pipe to communicate with the child. */
368 error = CreatePipe(&read_pipe, &write_pipe, &sa, 0);
370 VLOG_FATAL("CreatePipe failed (%s)", ovs_lasterror_to_string());
375 /* To the child, we pass an extra argument '--pipe-handle=write_pipe' */
376 buffer = xasprintf("%s %s=%ld", GetCommandLine(), "--pipe-handle",
379 /* Create a detached child */
380 error = CreateProcess(NULL, buffer, NULL, NULL, TRUE, DETACHED_PROCESS,
381 NULL, NULL, &si, &pi);
383 VLOG_FATAL("CreateProcess failed (%s)", ovs_lasterror_to_string());
386 /* Close one end of the pipe in the parent. */
387 CloseHandle(write_pipe);
389 /* Block and wait for child to say it is ready. */
390 error = ReadFile(read_pipe, &ch, 1, NULL, NULL);
392 VLOG_FATAL("Failed to read from child (%s)",
393 ovs_lasterror_to_string());
395 /* The child has successfully started and is ready. */
403 fclose(filep_pidfile);
410 /* If a pidfile has been configured, creates it and stores the running
411 * process's pid in it. Ensures that the pidfile will be deleted when the
418 error = GetFileAttributes(pidfile);
419 if (error != INVALID_FILE_ATTRIBUTES) {
420 /* pidfile exists. Try to unlink() it. */
421 error = unlink(pidfile);
423 VLOG_FATAL("Failed to delete existing pidfile %s (%s)", pidfile,
424 ovs_strerror(errno));
428 filep_pidfile = fopen(pidfile, "w");
429 if (filep_pidfile == NULL) {
430 VLOG_FATAL("failed to open %s (%s)", pidfile, ovs_strerror(errno));
433 fatal_signal_add_hook(unlink_pidfile, NULL, NULL, true);
435 fprintf(filep_pidfile, "%d\n", _getpid());
436 if (fflush(filep_pidfile) == EOF) {
437 VLOG_FATAL("Failed to write into the pidfile %s", pidfile);
440 /* Don't close the pidfile till the process exits. */
443 void daemonize_start(void)
451 daemonize_complete(void)
453 /* If running as a child because '--detach' option was specified,
454 * communicate with the parent to inform that the child is ready. */
458 close_standard_fds();
460 error = WriteFile(write_handle, "a", 1, NULL, NULL);
462 VLOG_FATAL("Failed to communicate with the parent (%s)",
463 ovs_lasterror_to_string());
470 /* Returns the file name that would be used for a pidfile if 'name' were
471 * provided to set_pidfile(). The caller must free the returned string. */
473 make_pidfile_name(const char *name)
475 if (name && strchr(name, ':')) {
478 return xasprintf("%s/%s.pid", ovs_rundir(), program_name);