Windows: Make pg_ctl reliably detect service status

pg_ctl is using isatty() to verify whether the process is running in a
terminal, and if not it sends its output to Windows' Event Log ... which
does the wrong thing when the output has been redirected to a pipe, as
reported in bug #13592.

To fix, make pg_ctl use the code we already have to detect service-ness:
in the master branch, move src/backend/port/win32/security.c to src/port
(with suitable tweaks so that it runs properly in backend and frontend
environments); pg_ctl already has access to pgport so it Just Works.  In
older branches, that's likely to cause trouble, so instead duplicate the
required code in pg_ctl.c.

Author: Michael Paquier
Bug report and diagnosis: Egon Kocjan
Backpatch: all supported branches

src/backend/port/win32/Makefile

@@ -12,7 +12,7 @@ subdir = src/backend/port/win32
 top_builddir = ../../../..
 include $(top_builddir)/src/Makefile.global
 
-OBJS = timer.o socket.o signal.o security.o mingwcompat.o
+OBJS = timer.o socket.o signal.o mingwcompat.o
 ifeq ($(have_win32_dbghelp), yes)
 OBJS += crashdump.o
 endif

src/bin/pg_ctl/pg_ctl.c

@@ -216,7 +216,7 @@ write_stderr(const char *fmt,...)
 	 * On Win32, we print to stderr if running on a console, or write to
 	 * eventlog if running as a service
 	 */
-	if (!isatty(fileno(stderr)))	/* Running as a service */
+	if (!pgwin32_is_service())	/* Running as a service */
 	{
 		char		errbuf[2048];		/* Arbitrary size? */
 

src/include/port/win32.h

@@ -382,9 +382,6 @@ int			pgwin32_waitforsinglesocket(SOCKET s, int what, int timeout);
 
 extern int	pgwin32_noblock;
 
-/* in backend/port/win32/security.c */
-extern int	pgwin32_is_admin(void);
-extern int	pgwin32_is_service(void);
 #endif
 
 /* in backend/port/win32_shmem.c */
@@ -400,6 +397,10 @@ extern void _dosmaperr(unsigned long);
 extern int	pgwin32_putenv(const char *);
 extern void pgwin32_unsetenv(const char *);
 
+/* in port/win32security.c */
+extern int	pgwin32_is_service(void);
+extern int	pgwin32_is_admin(void);
+
 #define putenv(x) pgwin32_putenv(x)
 #define unsetenv(x) pgwin32_unsetenv(x)
 

src/port/win32security.c

@@ -1,22 +1,47 @@
 /*-------------------------------------------------------------------------
  *
- * security.c
+ * win32security.c
  *	  Microsoft Windows Win32 Security Support Functions
  *
  * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  src/backend/port/win32/security.c
+ *	  src/port/win32security.c
  *
  *-------------------------------------------------------------------------
  */
 
+#ifndef FRONTEND
 #include "postgres.h"
+#else
+#include "postgres_fe.h"
+#endif
 
 
 static BOOL pgwin32_get_dynamic_tokeninfo(HANDLE token,
-							TOKEN_INFORMATION_CLASS class, char **InfoBuffer,
-							  char *errbuf, int errsize);
+							  TOKEN_INFORMATION_CLASS class,
+							  char **InfoBuffer, char *errbuf, int errsize);
+
+
+/*
+ * Utility wrapper for frontend and backend when reporting an error
+ * message.
+ */
+static
+pg_attribute_printf(1, 2)
+void
+log_error(const char *fmt,...)
+{
+	va_list		ap;
+
+	va_start(fmt, ap);
+#ifndef FRONTEND
+	write_stderr(fmt, ap);
+#else
+	fprintf(stderr, fmt, ap);
+#endif
+	va_end(ap);
+}
 
 /*
  * Returns nonzero if the current user has administrative privileges,
@@ -40,15 +65,15 @@ pgwin32_is_admin(void)
 
 	if (!OpenProcessToken(GetCurrentProcess(), TOKEN_READ, &AccessToken))
 	{
-		write_stderr("could not open process token: error code %lu\n",
-					 GetLastError());
+		log_error("could not open process token: error code %lu\n",
+				  GetLastError());
 		exit(1);
 	}
 
 	if (!pgwin32_get_dynamic_tokeninfo(AccessToken, TokenGroups,
 									   &InfoBuffer, errbuf, sizeof(errbuf)))
 	{
-		write_stderr("%s", errbuf);
+		log_error("%s", errbuf);
 		exit(1);
 	}
 
@@ -57,20 +82,22 @@ pgwin32_is_admin(void)
 	CloseHandle(AccessToken);
 
 	if (!AllocateAndInitializeSid(&NtAuthority, 2,
-		 SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_ADMINS, 0, 0, 0, 0, 0,
+								  SECURITY_BUILTIN_DOMAIN_RID,
+								  DOMAIN_ALIAS_RID_ADMINS, 0, 0, 0, 0, 0,
 								  0, &AdministratorsSid))
 	{
-		write_stderr("could not get SID for Administrators group: error code %lu\n",
-					 GetLastError());
+		log_error("could not get SID for Administrators group: error code %lu\n",
+				  GetLastError());
 		exit(1);
 	}
 
 	if (!AllocateAndInitializeSid(&NtAuthority, 2,
-	SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_POWER_USERS, 0, 0, 0, 0, 0,
+								  SECURITY_BUILTIN_DOMAIN_RID,
+								  DOMAIN_ALIAS_RID_POWER_USERS, 0, 0, 0, 0, 0,
 								  0, &PowerUsersSid))
 	{
-		write_stderr("could not get SID for PowerUsers group: error code %lu\n",
-					 GetLastError());
+		log_error("could not get SID for PowerUsers group: error code %lu\n",
+				  GetLastError());
 		exit(1);
 	}
 
@@ -78,8 +105,10 @@ pgwin32_is_admin(void)
 
 	for (x = 0; x < Groups->GroupCount; x++)
 	{
-		if ((EqualSid(AdministratorsSid, Groups->Groups[x].Sid) && (Groups->Groups[x].Attributes & SE_GROUP_ENABLED)) ||
-			(EqualSid(PowerUsersSid, Groups->Groups[x].Sid) && (Groups->Groups[x].Attributes & SE_GROUP_ENABLED)))
+		if ((EqualSid(AdministratorsSid, Groups->Groups[x].Sid) &&
+			 (Groups->Groups[x].Attributes & SE_GROUP_ENABLED)) ||
+			(EqualSid(PowerUsersSid, Groups->Groups[x].Sid) &&
+			 (Groups->Groups[x].Attributes & SE_GROUP_ENABLED)))
 		{
 			success = TRUE;
 			break;
@@ -105,9 +134,10 @@ pgwin32_is_admin(void)
  *	 1 = Service
  *	-1 = Error
  *
- * Note: we can't report errors via either ereport (we're called too early)
- * or write_stderr (because that calls this).  We are therefore reduced to
- * writing directly on stderr, which sucks, but we have few alternatives.
+ * Note: we can't report errors via either ereport (we're called too early
+ * in the backend) or write_stderr (because that calls this).  We are
+ * therefore reduced to writing directly on stderr, which sucks, but we
+ * have few alternatives.
  */
 int
 pgwin32_is_service(void)
@@ -217,13 +247,15 @@ pgwin32_get_dynamic_tokeninfo(HANDLE token, TOKEN_INFORMATION_CLASS class,
 
 	if (GetTokenInformation(token, class, NULL, 0, &InfoBufferSize))
 	{
-		snprintf(errbuf, errsize, "could not get token information: got zero size\n");
+		snprintf(errbuf, errsize,
+				 "could not get token information: got zero size\n");
 		return FALSE;
 	}
 
 	if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
 	{
-		snprintf(errbuf, errsize, "could not get token information: error code %lu\n",
+		snprintf(errbuf, errsize,
+				 "could not get token information: error code %lu\n",
 				 GetLastError());
 		return FALSE;
 	}
@@ -231,7 +263,8 @@ pgwin32_get_dynamic_tokeninfo(HANDLE token, TOKEN_INFORMATION_CLASS class,
 	*InfoBuffer = malloc(InfoBufferSize);
 	if (*InfoBuffer == NULL)
 	{
-		snprintf(errbuf, errsize, "could not allocate %d bytes for token information\n",
+		snprintf(errbuf, errsize,
+				 "could not allocate %d bytes for token information\n",
 				 (int) InfoBufferSize);
 		return FALSE;
 	}
@@ -239,7 +272,8 @@ pgwin32_get_dynamic_tokeninfo(HANDLE token, TOKEN_INFORMATION_CLASS class,
 	if (!GetTokenInformation(token, class, *InfoBuffer,
 							 InfoBufferSize, &InfoBufferSize))
 	{
-		snprintf(errbuf, errsize, "could not get token information: error code %lu\n",
+		snprintf(errbuf, errsize,
+				 "could not get token information: error code %lu\n",
 				 GetLastError());
 		return FALSE;
 	}

src/tools/msvc/Mkvcbuild.pm

@@ -90,7 +90,7 @@ sub mkvcbuild
 	  pgcheckdir.c pgmkdirp.c pgsleep.c pgstrcasecmp.c pqsignal.c
 	  mkdtemp.c qsort.c qsort_arg.c quotes.c system.c
 	  sprompt.c tar.c thread.c getopt.c getopt_long.c dirent.c
-	  win32env.c win32error.c win32setlocale.c);
+	  win32env.c win32error.c win32security.c win32setlocale.c);
 
 	push(@pgportfiles, 'rint.c') if ($vsVersion < '12.00');