X-Git-Url: http://git.iain.cx/?a=blobdiff_plain;f=process.cpp;h=b55da50c215d3bb50cb66994ecafb130aed721fb;hb=40792fac2ef98e69c331b9cd5a9279dc3e1eb730;hp=15fc83dce1b7f2e8ec19846cfc649be5f48e8b80;hpb=8d8036e4f1be4ba52898170345a9f8be0f327238;p=nssm.git

diff --git a/process.cpp b/process.cpp
index 15fc83d..b55da50 100644
--- a/process.cpp
+++ b/process.cpp
@@ -1,14 +1,241 @@
 #include "nssm.h"
 
-void kill_process_tree(char *service_name, unsigned long pid, unsigned long exitcode, unsigned long ppid) {
-  log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_KILLING, service_name, pid, exitcode, 0);
+int get_process_creation_time(HANDLE process_handle, FILETIME *ft) {
+  FILETIME creation_time, exit_time, kernel_time, user_time;
 
+  if (! GetProcessTimes(process_handle, &creation_time, &exit_time, &kernel_time, &user_time)) {
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_GETPROCESSTIMES_FAILED, error_string(GetLastError()), 0);
+    return 1;
+  }
+
+  memmove(ft, &creation_time, sizeof(creation_time));
+
+  return 0;
+}
+
+int get_process_exit_time(HANDLE process_handle, FILETIME *ft) {
+  FILETIME creation_time, exit_time, kernel_time, user_time;
+
+  if (! GetProcessTimes(process_handle, &creation_time, &exit_time, &kernel_time, &user_time)) {
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_GETPROCESSTIMES_FAILED, error_string(GetLastError()), 0);
+    return 1;
+  }
+
+  memmove(ft, &exit_time, sizeof(exit_time));
+
+  return 0;
+}
+
+int check_parent(char *service_name, PROCESSENTRY32 *pe, unsigned long ppid, FILETIME *pft, FILETIME *exit_time) {
+  /* Check parent process ID matches. */
+  if (pe->th32ParentProcessID != ppid) return 1;
+
+  /*
+    Process IDs can be reused so do a sanity check by making sure the child
+    has been running for less time than the parent.
+    Though unlikely, it's possible that the parent exited and its process ID
+    was already reused, so we'll also compare against its exit time.
+  */
+  HANDLE process_handle = OpenProcess(PROCESS_QUERY_INFORMATION, false, pe->th32ProcessID);
+  if (! process_handle) {
+    char pid_string[16];
+    _snprintf(pid_string, sizeof(pid_string), "%d", pe->th32ProcessID);
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OPENPROCESS_FAILED, pid_string, service_name, error_string(GetLastError()), 0);
+    return 2;
+  }
+
+  FILETIME ft;
+  if (get_process_creation_time(process_handle, &ft)) {
+    CloseHandle(process_handle);
+    return 3;
+  }
+
+  CloseHandle(process_handle);
+
+  /* Verify that the parent's creation time is not later. */
+  if (CompareFileTime(pft, &ft) > 0) return 4;
+
+  /* Verify that the parent's exit time is not earlier. */
+  if (CompareFileTime(exit_time, &ft) < 0) return 5;
+
+  return 0;
+}
+
+/* Send some window messages and hope the window respects one or more. */
+int CALLBACK kill_window(HWND window, LPARAM arg) {
+  kill_t *k = (kill_t *) arg;
+
+  unsigned long pid;
+  if (! GetWindowThreadProcessId(window, &pid)) return 1;
+  if (pid != k->pid) return 1;
+
+  /* First try sending WM_CLOSE to request that the window close. */
+  k->signalled |= PostMessage(window, WM_CLOSE, k->exitcode, 0);
+
+  /*
+    Then tell the window that the user is logging off and it should exit
+    without worrying about saving any data.
+  */
+  k->signalled |= PostMessage(window, WM_ENDSESSION, 1, ENDSESSION_CLOSEAPP | ENDSESSION_CRITICAL | ENDSESSION_LOGOFF);
+
+  return 1;
+}
+
+/*
+  Try to post a message to the message queues of threads associated with the
+  given process ID.  Not all threads have message queues so there's no
+  guarantee of success, and we don't want to be left waiting for unsignalled
+  processes so this function returns only true if at least one thread was
+  successfully prodded.
+*/
+int kill_threads(char *service_name, kill_t *k) {
+  int ret = 0;
+
+  /* Get a snapshot of all threads in the system. */
+  HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0);
+  if (! snapshot) {
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATETOOLHELP32SNAPSHOT_THREAD_FAILED, service_name, error_string(GetLastError()), 0);
+    return 0;
+  }
+
+  THREADENTRY32 te;
+  ZeroMemory(&te, sizeof(te));
+  te.dwSize = sizeof(te);
+
+  if (! Thread32First(snapshot, &te)) {
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_THREAD_ENUMERATE_FAILED, service_name, error_string(GetLastError()), 0);
+    CloseHandle(snapshot);
+    return 0;
+  }
+
+  /* This thread belongs to the doomed process so signal it. */
+  if (te.th32OwnerProcessID == k->pid) {
+    ret |= PostThreadMessage(te.th32ThreadID, WM_QUIT, k->exitcode, 0);
+  }
+
+  while (true) {
+    /* Try to get the next thread. */
+    if (! Thread32Next(snapshot, &te)) {
+      unsigned long error = GetLastError();
+      if (error == ERROR_NO_MORE_FILES) break;
+      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_THREAD_ENUMERATE_FAILED, service_name, error_string(GetLastError()), 0);
+      CloseHandle(snapshot);
+      return ret;
+    }
+
+    if (te.th32OwnerProcessID == k->pid) {
+      ret |= PostThreadMessage(te.th32ThreadID, WM_QUIT, k->exitcode, 0);
+    }
+  }
+
+  CloseHandle(snapshot);
+
+  return ret;
+}
+
+/* Give the process a chance to die gracefully. */
+int kill_process(char *service_name, HANDLE process_handle, unsigned long pid, unsigned long exitcode) {
   /* Shouldn't happen. */
+  if (! pid) return 1;
+  if (! process_handle) return 1;
+
+  unsigned long ret;
+  if (GetExitCodeProcess(process_handle, &ret)) {
+    if (ret != STILL_ACTIVE) return 1;
+  }
+
+  kill_t k = { pid, exitcode, 0 };
+
+  /* Try to send a Control-C event to the console. */
+  if (! kill_console(service_name, process_handle, pid)) return 1;
+
+  /*
+    Try to post messages to the windows belonging to the given process ID.
+    If the process is a console application it won't have any windows so there's
+    no guarantee of success.
+  */
+  EnumWindows((WNDENUMPROC) kill_window, (LPARAM) &k);
+  if (k.signalled) {
+    if (! WaitForSingleObject(process_handle, NSSM_KILL_WINDOW_GRACE_PERIOD)) return 1;
+  }
+
+  /*
+    Try to post messages to any thread message queues associated with the
+    process.  Console applications might have them (but probably won't) so
+    there's still no guarantee of success.
+  */
+  if (kill_threads(service_name, &k)) {
+    if (! WaitForSingleObject(process_handle, NSSM_KILL_THREADS_GRACE_PERIOD)) return 1;
+  }
+
+  /* We tried being nice.  Time for extreme prejudice. */
+  return TerminateProcess(process_handle, exitcode);
+}
+
+/* Simulate a Control-C event to our console (shared with the app). */
+int kill_console(char *service_name, HANDLE process_handle, unsigned long pid) {
+  unsigned long ret;
+
+  /* Try to attach to the process's console. */
+  if (! AttachConsole(pid)) {
+    ret = GetLastError();
+
+    switch (ret) {
+      case ERROR_INVALID_HANDLE:
+        /* The app doesn't have a console. */
+        return 1;
+
+      case ERROR_GEN_FAILURE:
+        /* The app already exited. */
+        return 2;
+
+      case ERROR_ACCESS_DENIED:
+      default:
+        /* We already have a console. */
+        log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_ATTACHCONSOLE_FAILED, service_name, error_string(ret), 0);
+        return 3;
+    }
+  }
+
+  /* Ignore the event ourselves. */
+  ret = 0;
+  if (! SetConsoleCtrlHandler(0, TRUE)) {
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_SETCONSOLECTRLHANDLER_FAILED, service_name, error_string(GetLastError()), 0);
+    ret = 4;
+  }
+
+  /* Sent the event. */
+  if (! ret) {
+    if (! GenerateConsoleCtrlEvent(CTRL_C_EVENT, 0)) {
+      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_GENERATECONSOLECTRLEVENT_FAILED, service_name, error_string(GetLastError()), 0);
+      ret = 5;
+    }
+  }
+
+  /* Detach from the console. */
+  if (! FreeConsole()) {
+    log_event(EVENTLOG_WARNING_TYPE, NSSM_EVENT_FREECONSOLE_FAILED, service_name, error_string(GetLastError()), 0);
+  }
+
+  /* Wait for process to exit. */
+  if (! WaitForSingleObject(process_handle, NSSM_KILL_CONSOLE_GRACE_PERIOD)) return 6;
+
+  return ret;
+}
+
+void kill_process_tree(char *service_name, unsigned long pid, unsigned long exitcode, unsigned long ppid, FILETIME *parent_creation_time, FILETIME *parent_exit_time) {
+  /* Shouldn't happen unless the service failed to start. */
   if (! pid) return;
 
+  char pid_string[16], code[16];
+  _snprintf(pid_string, sizeof(pid_string), "%d", pid);
+  _snprintf(code, sizeof(code), "%d", exitcode);
+  log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_KILLING, service_name, pid_string, code, 0);
+
+  /* Get a snapshot of all processes in the system. */
   HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
   if (! snapshot) {
-    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATETOOLHELP32SNAPSHOT_FAILED, service_name, GetLastError(), 0);
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATETOOLHELP32SNAPSHOT_PROCESS_FAILED, service_name, error_string(GetLastError()), 0);
     return;
   }
 
@@ -17,33 +244,44 @@ void kill_process_tree(char *service_name, unsigned long pid, unsigned long exit
   pe.dwSize = sizeof(pe);
 
   if (! Process32First(snapshot, &pe)) {
-    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_PROCESS_ENUMERATE_FAILED, service_name, GetLastError(), 0);
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_PROCESS_ENUMERATE_FAILED, service_name, error_string(GetLastError()), 0);
+    CloseHandle(snapshot);
     return;
   }
 
-  if (pe.th32ParentProcessID == pid) kill_process_tree(service_name, pe.th32ProcessID, exitcode, ppid);
+  /* This is a child of the doomed process so kill it. */
+  if (! check_parent(service_name, &pe, pid, parent_creation_time, parent_exit_time)) kill_process_tree(service_name, pe.th32ProcessID, exitcode, ppid, parent_creation_time, parent_exit_time);
 
   while (true) {
     /* Try to get the next process. */
     if (! Process32Next(snapshot, &pe)) {
       unsigned long ret = GetLastError();
       if (ret == ERROR_NO_MORE_FILES) break;
-      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_PROCESS_ENUMERATE_FAILED, service_name, GetLastError(), 0);
+      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_PROCESS_ENUMERATE_FAILED, service_name, error_string(GetLastError()), 0);
+      CloseHandle(snapshot);
       return;
     }
 
-    if (pe.th32ParentProcessID == pid) kill_process_tree(service_name, pe.th32ProcessID, exitcode, ppid);
+    if (! check_parent(service_name, &pe, pid, parent_creation_time, parent_exit_time)) kill_process_tree(service_name, pe.th32ProcessID, exitcode, ppid, parent_creation_time, parent_exit_time);
   }
 
+  CloseHandle(snapshot);
+
+  /* We will need a process handle in order to call TerminateProcess() later. */
   HANDLE process_handle = OpenProcess(SYNCHRONIZE | PROCESS_QUERY_INFORMATION | PROCESS_VM_READ | PROCESS_TERMINATE, false, pid);
   if (! process_handle) {
-    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OPENPROCESS_FAILED, pid, service_name, GetLastError(), 0);
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OPENPROCESS_FAILED, pid_string, service_name, error_string(GetLastError()), 0);
     return;
   }
 
-  log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_KILL_PROCESS_TREE, pid, ppid, service_name, 0);
-  if (! TerminateProcess(process_handle, exitcode)) {
-    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_TERMINATEPROCESS_FAILED, pid, service_name, GetLastError(), 0);
-    return;
+  char ppid_string[16];
+  _snprintf(ppid_string, sizeof(ppid_string), "%d", ppid);
+  log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_KILL_PROCESS_TREE, pid_string, ppid_string, service_name, 0);
+  if (! kill_process(service_name, process_handle, pid, exitcode)) {
+    /* Maybe it already died. */
+    unsigned long ret;
+    if (! GetExitCodeProcess(process_handle, &ret) || ret == STILL_ACTIVE) log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_TERMINATEPROCESS_FAILED, pid_string, service_name, error_string(GetLastError()), 0);
   }
+
+  CloseHandle(process_handle);
 }