Enable on-demand rotation.
[nssm.git] / io.cpp
diff --git a/io.cpp b/io.cpp
index 30deb72..79848e9 100644 (file)
--- a/io.cpp
+++ b/io.cpp
@@ -1,5 +1,27 @@
 #include "nssm.h"\r
 \r
+#define COMPLAINED_READ (1 << 0)\r
+#define COMPLAINED_WRITE (1 << 1)\r
+#define COMPLAINED_ROTATE (1 << 2)\r
+\r
+static HANDLE create_logging_thread(logger_t *logger) {\r
+  HANDLE thread_handle = CreateThread(NULL, 0, log_and_rotate, (void *) logger, 0, logger->tid_ptr);\r
+  if (! thread_handle) log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATETHREAD_FAILED, error_string(GetLastError()), 0);\r
+  return thread_handle;\r
+}\r
+\r
+static inline unsigned long guess_charsize(void *address, unsigned long bufsize) {\r
+  if (IsTextUnicode(address, bufsize, 0)) return (unsigned long) sizeof(wchar_t);\r
+  else return (unsigned long) sizeof(char);\r
+}\r
+\r
+static inline void write_bom(logger_t *logger, unsigned long *out) {\r
+  wchar_t bom = L'\ufeff';\r
+  if (! WriteFile(logger->write_handle, (void *) &bom, sizeof(bom), out, 0)) {\r
+    log_event(EVENTLOG_WARNING_TYPE, NSSM_EVENT_SOMEBODY_SET_UP_US_THE_BOM, logger->service_name, logger->path, error_string(GetLastError()), 0);\r
+  }\r
+}\r
+\r
 /* Get path, share mode, creation disposition and flags for a stream. */\r
 int get_createfile_parameters(HKEY key, TCHAR *prefix, TCHAR *path, unsigned long *sharing, unsigned long default_sharing, unsigned long *disposition, unsigned long default_disposition, unsigned long *flags, unsigned long default_flags) {\r
   TCHAR value[NSSM_STDIO_LENGTH];\r
@@ -61,6 +83,18 @@ int set_createfile_parameter(HKEY key, TCHAR *prefix, TCHAR *suffix, unsigned lo
   return set_number(key, value, number);\r
 }\r
 \r
+int delete_createfile_parameter(HKEY key, TCHAR *prefix, TCHAR *suffix) {\r
+  TCHAR value[NSSM_STDIO_LENGTH];\r
+\r
+  if (_sntprintf_s(value, _countof(value), _TRUNCATE, _T("%s%s"), prefix, suffix) < 0) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, suffix, _T("delete_createfile_parameter()"), 0);\r
+    return 1;\r
+  }\r
+\r
+  if (RegDeleteValue(key, value)) return 0;\r
+  return 1;\r
+}\r
+\r
 HANDLE append_to_file(TCHAR *path, unsigned long sharing, SECURITY_ATTRIBUTES *attributes, unsigned long disposition, unsigned long flags) {\r
   HANDLE ret;\r
 \r
@@ -73,7 +107,7 @@ HANDLE append_to_file(TCHAR *path, unsigned long sharing, SECURITY_ATTRIBUTES *a
 \r
   unsigned long error = GetLastError();\r
   if (error != ERROR_FILE_NOT_FOUND) {\r
-    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEFILE_FAILED, path, error_string(error));\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEFILE_FAILED, path, error_string(error), 0);\r
     return (HANDLE) 0;\r
   }\r
 \r
@@ -81,6 +115,22 @@ HANDLE append_to_file(TCHAR *path, unsigned long sharing, SECURITY_ATTRIBUTES *a
   return CreateFile(path, FILE_WRITE_DATA, sharing, attributes, disposition, flags, 0);\r
 }\r
 \r
+static void rotated_filename(TCHAR *path, TCHAR *rotated, unsigned long rotated_len, SYSTEMTIME *st) {\r
+  if (! st) {\r
+    SYSTEMTIME now;\r
+    st = &now;\r
+    GetSystemTime(st);\r
+  }\r
+\r
+  TCHAR buffer[MAX_PATH];\r
+  memmove(buffer, path, sizeof(buffer));\r
+  TCHAR *ext = PathFindExtension(buffer);\r
+  TCHAR extension[MAX_PATH];\r
+  _sntprintf_s(extension, _countof(extension), _TRUNCATE, _T("-%04u%02u%02uT%02u%02u%02u.%03u%s"), st->wYear, st->wMonth, st->wDay, st->wHour, st->wMinute, st->wSecond, st->wMilliseconds, ext);\r
+  *ext = _T('\0');\r
+  _sntprintf_s(rotated, rotated_len, _TRUNCATE, _T("%s%s"), buffer, extension);\r
+}\r
+\r
 void rotate_file(TCHAR *service_name, TCHAR *path, unsigned long seconds, unsigned long low, unsigned long high) {\r
   unsigned long error;\r
 \r
@@ -134,27 +184,22 @@ void rotate_file(TCHAR *service_name, TCHAR *path, unsigned long seconds, unsign
   /* Get new filename. */\r
   FileTimeToSystemTime(&info.ftLastWriteTime, &st);\r
 \r
-  TCHAR buffer[MAX_PATH];\r
-  memmove(buffer, path, sizeof(buffer));\r
-  TCHAR *ext = PathFindExtension(buffer);\r
-  TCHAR extension[MAX_PATH];\r
-  _sntprintf_s(extension, _countof(extension), _TRUNCATE, _T("-%04u%02u%02uT%02u%02u%02u.%03u%s"), st.wYear, st.wMonth, st.wDay, st.wHour, st.wMinute, st.wSecond, st.wMilliseconds, ext);\r
-  *ext = _T('\0');\r
   TCHAR rotated[MAX_PATH];\r
-  _sntprintf_s(rotated, _countof(rotated), _TRUNCATE, _T("%s%s"), buffer, extension);\r
+  rotated_filename(path, rotated, _countof(rotated), &st);\r
 \r
   /* Rotate. */\r
-  if (MoveFile(path, rotated)) return;\r
+  if (MoveFile(path, rotated)) {\r
+    log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_ROTATED, service_name, path, rotated, 0);\r
+    return;\r
+  }\r
   error = GetLastError();\r
 \r
+  if (error == ERROR_FILE_NOT_FOUND) return;\r
   log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_ROTATE_FILE_FAILED, service_name, path, _T("MoveFile()"), rotated, error_string(error), 0);\r
   return;\r
 }\r
 \r
 int get_output_handles(nssm_service_t *service, HKEY key, STARTUPINFO *si) {\r
-  TCHAR path[MAX_PATH];\r
-  TCHAR stdout_path[MAX_PATH];\r
-  unsigned long sharing, disposition, flags;\r
   bool set_flags = false;\r
 \r
   /* Standard security attributes allowing inheritance. */\r
@@ -163,52 +208,166 @@ int get_output_handles(nssm_service_t *service, HKEY key, STARTUPINFO *si) {
   attributes.bInheritHandle = true;\r
 \r
   /* stdin */\r
-  if (get_createfile_parameters(key, NSSM_REG_STDIN, path, &sharing, NSSM_STDIN_SHARING, &disposition, NSSM_STDIN_DISPOSITION, &flags, NSSM_STDIN_FLAGS)) return 1;\r
-  if (path[0]) {\r
-    si->hStdInput = CreateFile(path, FILE_READ_DATA, sharing, &attributes, disposition, flags, 0);\r
+  if (get_createfile_parameters(key, NSSM_REG_STDIN, service->stdin_path, &service->stdin_sharing, NSSM_STDIN_SHARING, &service->stdin_disposition, NSSM_STDIN_DISPOSITION, &service->stdin_flags, NSSM_STDIN_FLAGS)) {\r
+    service->stdin_sharing = service->stdin_disposition = service->stdin_flags = 0;\r
+    ZeroMemory(service->stdin_path, _countof(service->stdin_path) * sizeof(TCHAR));\r
+    return 1;\r
+  }\r
+  if (si && service->stdin_path[0]) {\r
+    si->hStdInput = CreateFile(service->stdin_path, FILE_READ_DATA, service->stdin_sharing, &attributes, service->stdin_disposition, service->stdin_flags, 0);\r
     if (! si->hStdInput) {\r
-      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEFILE_FAILED, path, error_string(GetLastError()));\r
+      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEFILE_FAILED, service->stdin_path, error_string(GetLastError()), 0);\r
       return 2;\r
     }\r
     set_flags = true;\r
   }\r
 \r
+  ULARGE_INTEGER size;\r
+  size.LowPart = service->rotate_bytes_low;\r
+  size.HighPart = service->rotate_bytes_high;\r
+\r
   /* stdout */\r
-  if (get_createfile_parameters(key, NSSM_REG_STDOUT, path, &sharing, NSSM_STDOUT_SHARING, &disposition, NSSM_STDOUT_DISPOSITION, &flags, NSSM_STDOUT_FLAGS)) return 3;\r
-  if (path[0]) {\r
-    /* Remember path for comparison with stderr. */\r
-    if (_sntprintf_s(stdout_path, _countof(stdout_path), _TRUNCATE, _T("%s"), path) < 0) {\r
-      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, _T("stdout_path"), _T("get_output_handles"), 0);\r
+  if (get_createfile_parameters(key, NSSM_REG_STDOUT, service->stdout_path, &service->stdout_sharing, NSSM_STDOUT_SHARING, &service->stdout_disposition, NSSM_STDOUT_DISPOSITION, &service->stdout_flags, NSSM_STDOUT_FLAGS)) {\r
+    service->stdout_sharing = service->stdout_disposition = service->stdout_flags = 0;\r
+    ZeroMemory(service->stdout_path, _countof(service->stdout_path) * sizeof(TCHAR));\r
+    return 3;\r
+  }\r
+  if (si && service->stdout_path[0]) {\r
+    if (service->rotate_files) rotate_file(service->name, service->stdout_path, service->rotate_seconds, service->rotate_bytes_low, service->rotate_bytes_high);\r
+    HANDLE stdout_handle = append_to_file(service->stdout_path, service->stdout_sharing, 0, service->stdout_disposition, service->stdout_flags);\r
+    if (! stdout_handle) {\r
+      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEFILE_FAILED, service->stdout_path, error_string(GetLastError()), 0);\r
       return 4;\r
     }\r
 \r
-    if (service->rotate_files) rotate_file(service->name, path, service->rotate_seconds, service->rotate_bytes_low, service->rotate_bytes_high);\r
-    si->hStdOutput = append_to_file(path, sharing, &attributes, disposition, flags);\r
-    if (! si->hStdOutput) return 5;\r
+    /* Try online rotation only if a size threshold is set. */\r
+    logger_t *stdout_logger = 0;\r
+    if (service->rotate_files && service->rotate_stdout_online) {\r
+      stdout_logger = (logger_t *) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(logger_t));\r
+      if (stdout_logger) {\r
+        /* Pipe between application's stdout and our logging handle. */\r
+        if (CreatePipe(&service->stdout_pipe, &si->hStdOutput, &attributes, 0)) {\r
+          stdout_logger->service_name = service->name;\r
+          stdout_logger->path = service->stdout_path;\r
+          stdout_logger->sharing = service->stdout_sharing;\r
+          stdout_logger->disposition = service->stdout_disposition;\r
+          stdout_logger->flags = service->stdout_flags;\r
+          stdout_logger->read_handle = service->stdout_pipe;\r
+          stdout_logger->write_handle = stdout_handle;\r
+          stdout_logger->size = (__int64) size.QuadPart;\r
+          stdout_logger->tid_ptr = &service->stdout_tid;\r
+          stdout_logger->rotate_online = &service->rotate_stdout_online;\r
+\r
+          /* Logging thread. */\r
+          service->stdout_thread = create_logging_thread(stdout_logger);\r
+          if (! service->stdout_thread) {\r
+            log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEPIPE_FAILED, service->name, service->stdout_path, error_string(GetLastError()));\r
+            CloseHandle(service->stdout_pipe);\r
+            CloseHandle(si->hStdOutput);\r
+            service->stdout_tid = 0;\r
+          }\r
+        }\r
+        else service->stdout_tid = 0;\r
+      }\r
+      else {\r
+        log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, _T("stdout_logger"), _T("get_output_handles()"), 0);\r
+        service->stdout_tid = 0;\r
+      }\r
+\r
+      /* Fall through to try direct I/O. */\r
+      if (! service->stdout_tid) log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEPIPE_FAILED, service->name, service->stdout_path, error_string(GetLastError()));\r
+    }\r
+\r
+    if (! service->stdout_tid) {\r
+      if (stdout_logger) HeapFree(GetProcessHeap(), 0, stdout_logger);\r
+      if (! DuplicateHandle(GetCurrentProcess(), stdout_handle, GetCurrentProcess(), &si->hStdOutput, 0, true, DUPLICATE_CLOSE_SOURCE | DUPLICATE_SAME_ACCESS)) {\r
+        log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_DUPLICATEHANDLE_FAILED, NSSM_REG_STDOUT, error_string(GetLastError()), 0);\r
+        return 4;\r
+      }\r
+      service->rotate_stdout_online = NSSM_ROTATE_OFFLINE;\r
+    }\r
+\r
     set_flags = true;\r
   }\r
-  else ZeroMemory(stdout_path, sizeof(stdout_path));\r
 \r
   /* stderr */\r
-  if (get_createfile_parameters(key, NSSM_REG_STDERR, path, &sharing, NSSM_STDERR_SHARING, &disposition, NSSM_STDERR_DISPOSITION, &flags, NSSM_STDERR_FLAGS)) return 6;\r
-  if (path[0]) {\r
+  if (get_createfile_parameters(key, NSSM_REG_STDERR, service->stderr_path, &service->stderr_sharing, NSSM_STDERR_SHARING, &service->stderr_disposition, NSSM_STDERR_DISPOSITION, &service->stderr_flags, NSSM_STDERR_FLAGS)) {\r
+    service->stderr_sharing = service->stderr_disposition = service->stderr_flags = 0;\r
+    ZeroMemory(service->stderr_path, _countof(service->stderr_path) * sizeof(TCHAR));\r
+    return 5;\r
+  }\r
+  if (service->stderr_path[0]) {\r
     /* Same as stdout? */\r
-    if (str_equiv(path, stdout_path)) {\r
-      /* Two handles to the same file will create a race. */\r
-      if (! DuplicateHandle(GetCurrentProcess(), si->hStdOutput, GetCurrentProcess(), &si->hStdError, 0, true, DUPLICATE_SAME_ACCESS)) {\r
-        log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_DUPLICATEHANDLE_FAILED, NSSM_REG_STDOUT, error_string(GetLastError()));\r
-        return 7;\r
+    if (str_equiv(service->stderr_path, service->stdout_path)) {\r
+      service->stderr_sharing = service->stdout_sharing;\r
+      service->stderr_disposition = service->stdout_disposition;\r
+      service->stderr_flags = service->stdout_flags;\r
+      service->rotate_stderr_online = false;\r
+\r
+      if (si) {\r
+        /* Two handles to the same file will create a race. */\r
+        if (! DuplicateHandle(GetCurrentProcess(), si->hStdOutput, GetCurrentProcess(), &si->hStdError, 0, true, DUPLICATE_SAME_ACCESS)) {\r
+          log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_DUPLICATEHANDLE_FAILED, NSSM_REG_STDOUT, error_string(GetLastError()), 0);\r
+          return 6;\r
+        }\r
       }\r
     }\r
-    else {\r
-      if (service->rotate_files) rotate_file(service->name, path, service->rotate_seconds, service->rotate_bytes_low, service->rotate_bytes_high);\r
-      si->hStdError = append_to_file(path, sharing, &attributes, disposition, flags);\r
-      if (! si->hStdError) {\r
-        log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEFILE_FAILED, path, error_string(GetLastError()));\r
-        return 8;\r
+    else if (si) {\r
+      if (service->rotate_files) rotate_file(service->name, service->stderr_path, service->rotate_seconds, service->rotate_bytes_low, service->rotate_bytes_high);\r
+      HANDLE stderr_handle = append_to_file(service->stderr_path, service->stderr_sharing, 0, service->stderr_disposition, service->stderr_flags);\r
+      if (! stderr_handle) {\r
+        log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEFILE_FAILED, service->stderr_path, error_string(GetLastError()), 0);\r
+        return 7;\r
+      }\r
+\r
+      /* Try online rotation only if a size threshold is set. */\r
+      logger_t *stderr_logger = 0;\r
+      if (service->rotate_files && service->rotate_stderr_online) {\r
+        stderr_logger = (logger_t *) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(logger_t));\r
+        if (stderr_logger) {\r
+          /* Pipe between application's stderr and our logging handle. */\r
+          if (CreatePipe(&service->stderr_pipe, &si->hStdError, &attributes, 0)) {\r
+            stderr_logger->service_name = service->name;\r
+            stderr_logger->path = service->stderr_path;\r
+            stderr_logger->sharing = service->stderr_sharing;\r
+            stderr_logger->disposition = service->stderr_disposition;\r
+            stderr_logger->flags = service->stderr_flags;\r
+            stderr_logger->read_handle = service->stderr_pipe;\r
+            stderr_logger->write_handle = stderr_handle;\r
+            stderr_logger->size = (__int64) size.QuadPart;\r
+            stderr_logger->tid_ptr = &service->stderr_tid;\r
+            stderr_logger->rotate_online = &service->rotate_stderr_online;\r
+\r
+            /* Logging thread. */\r
+            service->stderr_thread = create_logging_thread(stderr_logger);\r
+            if (! service->stderr_thread) {\r
+              log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEPIPE_FAILED, service->name, service->stderr_path, error_string(GetLastError()));\r
+              CloseHandle(service->stderr_pipe);\r
+              CloseHandle(si->hStdError);\r
+              service->stderr_tid = 0;\r
+            }\r
+          }\r
+          else service->stderr_tid = 0;\r
+        }\r
+        else {\r
+          log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, _T("stderr_logger"), _T("get_output_handles()"), 0);\r
+          service->stderr_tid = 0;\r
+        }\r
+\r
+        /* Fall through to try direct I/O. */\r
+        if (! service->stderr_tid) log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEPIPE_FAILED, service->name, service->stderr_path, error_string(GetLastError()));\r
+      }\r
+\r
+      if (! service->stderr_tid) {\r
+        if (stderr_logger) HeapFree(GetProcessHeap(), 0, stderr_logger);\r
+        if (! DuplicateHandle(GetCurrentProcess(), stderr_handle, GetCurrentProcess(), &si->hStdError, 0, true, DUPLICATE_CLOSE_SOURCE | DUPLICATE_SAME_ACCESS)) {\r
+          log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_DUPLICATEHANDLE_FAILED, NSSM_REG_STDERR, error_string(GetLastError()), 0);\r
+          return 7;\r
+        }\r
+        service->rotate_stderr_online = NSSM_ROTATE_OFFLINE;\r
       }\r
-      SetEndOfFile(si->hStdError);\r
     }\r
+\r
     set_flags = true;\r
   }\r
 \r
@@ -218,13 +377,217 @@ int get_output_handles(nssm_service_t *service, HKEY key, STARTUPINFO *si) {
     We need to set the startup_info flags to make the new handles\r
     inheritable by the new process.\r
   */\r
-  si->dwFlags |= STARTF_USESTDHANDLES;\r
+  if (si) si->dwFlags |= STARTF_USESTDHANDLES;\r
 \r
   return 0;\r
 }\r
 \r
-void close_output_handles(STARTUPINFO *si) {\r
+void close_output_handles(STARTUPINFO *si, bool close_stdout, bool close_stderr) {\r
   if (si->hStdInput) CloseHandle(si->hStdInput);\r
-  if (si->hStdOutput) CloseHandle(si->hStdOutput);\r
-  if (si->hStdError) CloseHandle(si->hStdError);\r
+  if (si->hStdOutput && close_stdout) CloseHandle(si->hStdOutput);\r
+  if (si->hStdError && close_stderr) CloseHandle(si->hStdError);\r
+}\r
+\r
+void close_output_handles(STARTUPINFO *si) {\r
+  return close_output_handles(si, true, true);\r
+}\r
+\r
+/*\r
+  Try multiple times to read from a file.\r
+  Returns:  0 on success.\r
+            1 on non-fatal error.\r
+           -1 on fatal error.\r
+*/\r
+static int try_read(logger_t *logger, void *address, unsigned long bufsize, unsigned long *in, int *complained) {\r
+  int ret = 1;\r
+  unsigned long error;\r
+  for (int tries = 0; tries < 5; tries++) {\r
+    if (ReadFile(logger->read_handle, address, bufsize, in, 0)) return 0;\r
+\r
+    error = GetLastError();\r
+    switch (error) {\r
+      /* Other end closed the pipe. */\r
+      case ERROR_BROKEN_PIPE:\r
+        ret = -1;\r
+        goto complain_read;\r
+\r
+      /* Couldn't lock the buffer. */\r
+      case ERROR_NOT_ENOUGH_QUOTA:\r
+        Sleep(2000 + tries * 3000);\r
+        ret = 1;\r
+        continue;\r
+\r
+      /* Write was cancelled by the other end. */\r
+      case ERROR_OPERATION_ABORTED:\r
+        ret = 1;\r
+        goto complain_read;\r
+\r
+      default:\r
+        ret = -1;\r
+    }\r
+  }\r
+\r
+complain_read:\r
+  if (! (*complained & COMPLAINED_READ)) log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_READFILE_FAILED, logger->service_name, logger->path, error_string(error), 0);\r
+  *complained |= COMPLAINED_READ;\r
+  return ret;\r
+}\r
+\r
+/*\r
+  Try multiple times to write to a file.\r
+  Returns:  0 on success.\r
+            1 on non-fatal error.\r
+           -1 on fatal error.\r
+*/\r
+static int try_write(logger_t *logger, void *address, unsigned long bufsize, unsigned long *out, int *complained) {\r
+  int ret = 1;\r
+  unsigned long error;\r
+  for (int tries = 0; tries < 5; tries++) {\r
+    if (WriteFile(logger->write_handle, address, bufsize, out, 0)) return 0;\r
+\r
+    error = GetLastError();\r
+    if (error == ERROR_IO_PENDING) {\r
+      /* Operation was successful pending flush to disk. */\r
+      return 0;\r
+    }\r
+\r
+    switch (error) {\r
+      /* Other end closed the pipe. */\r
+      case ERROR_BROKEN_PIPE:\r
+        ret = -1;\r
+        goto complain_write;\r
+\r
+      /* Couldn't lock the buffer. */\r
+      case ERROR_NOT_ENOUGH_QUOTA:\r
+      /* Out of disk space. */\r
+      case ERROR_DISK_FULL:\r
+        Sleep(2000 + tries * 3000);\r
+        ret = 1;\r
+        continue;\r
+\r
+      default:\r
+        /* We'll lose this line but try to read and write subsequent ones. */\r
+        ret = 1;\r
+    }\r
+  }\r
+\r
+complain_write:\r
+  if (! (*complained & COMPLAINED_WRITE)) log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_WRITEFILE_FAILED, logger->service_name, logger->path, error_string(error), 0);\r
+  *complained |= COMPLAINED_WRITE;\r
+  return ret;\r
+}\r
+\r
+/* Wrapper to be called in a new thread for logging. */\r
+unsigned long WINAPI log_and_rotate(void *arg) {\r
+  logger_t *logger = (logger_t *) arg;\r
+  if (! logger) return 1;\r
+\r
+  __int64 size;\r
+  BY_HANDLE_FILE_INFORMATION info;\r
+\r
+  /* Find initial file size. */\r
+  if (! GetFileInformationByHandle(logger->write_handle, &info)) logger->size = 0LL;\r
+  else {\r
+    ULARGE_INTEGER l;\r
+    l.HighPart = info.nFileSizeHigh;\r
+    l.LowPart = info.nFileSizeLow;\r
+    size = l.QuadPart;\r
+  }\r
+\r
+  char buffer[1024];\r
+  void *address;\r
+  unsigned long in, out;\r
+  unsigned long charsize = 0;\r
+  unsigned long error;\r
+  int ret;\r
+  int complained = 0;\r
+\r
+  while (true) {\r
+    /* Read data from the pipe. */\r
+    address = &buffer;\r
+    ret = try_read(logger, address, sizeof(buffer), &in, &complained);\r
+    if (ret < 0) {\r
+      HeapFree(GetProcessHeap(), 0, logger);\r
+      return 2;\r
+    }\r
+    else if (ret) continue;\r
+\r
+    if (*logger->rotate_online == NSSM_ROTATE_ONLINE_ASAP || (logger->size && size + (__int64) in >= logger->size)) {\r
+      /* Look for newline. */\r
+      unsigned long i;\r
+      for (i = 0; i < in; i++) {\r
+        if (buffer[i] == '\n') {\r
+          if (! charsize) charsize = guess_charsize(address, in);\r
+          i += charsize;\r
+\r
+          /* Write up to the newline. */\r
+          ret = try_write(logger, address, i, &out, &complained);\r
+          if (ret < 0) {\r
+            HeapFree(GetProcessHeap(), 0, logger);\r
+            return 3;\r
+          }\r
+          size += (__int64) out;\r
+\r
+          /* Rotate. */\r
+          *logger->rotate_online = NSSM_ROTATE_ONLINE;\r
+          TCHAR rotated[MAX_PATH];\r
+          rotated_filename(logger->path, rotated, _countof(rotated), 0);\r
+\r
+          /*\r
+            Ideally we'd try the rename first then close the handle but\r
+            MoveFile() will fail if the handle is still open so we must\r
+            risk losing everything.\r
+          */\r
+          CloseHandle(logger->write_handle);\r
+          if (MoveFile(logger->path, rotated)) {\r
+            log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_ROTATED, logger->service_name, logger->path, rotated, 0);\r
+            size = 0LL;\r
+          }\r
+          else {\r
+            error = GetLastError();\r
+            if (error != ERROR_FILE_NOT_FOUND) {\r
+              if (! (complained & COMPLAINED_ROTATE)) log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_ROTATE_FILE_FAILED, logger->service_name, logger->path, _T("MoveFile()"), rotated, error_string(error), 0);\r
+              complained |= COMPLAINED_ROTATE;\r
+              /* We can at least try to re-open the existing file. */\r
+              logger->disposition = OPEN_ALWAYS;\r
+            }\r
+          }\r
+\r
+          /* Reopen. */\r
+          logger->write_handle = append_to_file(logger->path, logger->sharing, 0, logger->disposition, logger->flags);\r
+          if (! logger->write_handle) {\r
+            error = GetLastError();\r
+            log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEFILE_FAILED, logger->path, error_string(error), 0);\r
+            /* Oh dear.  Now we can't log anything further. */\r
+            HeapFree(GetProcessHeap(), 0, logger);\r
+            return 4;\r
+          }\r
+\r
+          /* Resume writing after the newline. */\r
+          address = (void *) ((char *) address + i);\r
+          in -= i;\r
+        }\r
+      }\r
+    }\r
+\r
+    if (! size) {\r
+      /* Write a BOM to the new file. */\r
+      if (! charsize) charsize = guess_charsize(address, in);\r
+      if (charsize == sizeof(wchar_t)) write_bom(logger, &out);\r
+      size += (__int64) out;\r
+    }\r
+\r
+    /* Write the data, if any. */\r
+    if (! in) continue;\r
+\r
+    ret = try_write(logger, address, in, &out, &complained);\r
+    size += (__int64) out;\r
+    if (ret < 0) {\r
+      HeapFree(GetProcessHeap(), 0, logger);\r
+      return 3;\r
+    }\r
+  }\r
+\r
+  HeapFree(GetProcessHeap(), 0, logger);\r
+  return 0;\r
 }\r