Fix fseek() detection of unseekable files on WIN32

From 45ea3338e10c6b296ddc1cedb80ce8e5f103e51d Mon Sep 17 00:00:00 2001
From: Juan Jose Santamaria Flecha <juanjo.santamaria@gmail.com>
Date: Wed, 15 Mar 2023 07:04:44 -0400
Subject: [PATCH] fix fseek detection of unseekable files for WIN32

Calling fseek() on a handle to a non-seeking device such as a pipe or
a communications device is not supported, even though the fseek() may
not return an error, so harden that funcion with our version.
---
 src/include/port/win32_port.h |  9 ++++--
 src/port/meson.build          |  1 +
 src/port/win32fseek.c         | 68 +++++++++++++++++++++++++++++++++++++++++++
 src/tools/msvc/Mkvcbuild.pm   |  1 +
 4 files changed, 76 insertions(+), 3 deletions(-)
 create mode 100644 src/port/win32fseek.c

diff --git a/src/include/port/win32_port.h b/src/include/port/win32_port.h
index 9488195..66553fe 100644
--- a/src/include/port/win32_port.h
+++ b/src/include/port/win32_port.h
@@ -206,13 +206,16 @@ int			setitimer(int which, const struct itimerval *value, struct itimerval *oval
 
 /*
  * WIN32 does not provide 64-bit off_t, but does provide the functions operating
- * with 64-bit offsets.
+ * with 64-bit offsets. Also, fseek() might not give an error for unseekable
+ * streams, so harden that function with our version.
  */
 #define pgoff_t __int64
 
 #ifdef _MSC_VER
-#define fseeko(stream, offset, origin) _fseeki64(stream, offset, origin)
-#define ftello(stream) _ftelli64(stream)
+extern int  	_pgfseeko64(FILE *stream, pgoff_t offset, int origin);
+extern pgoff_t	_pgftello64(FILE *stream);
+#define fseeko(stream, offset, origin) _pgfseeko64(stream, offset, origin)
+#define ftello(stream) _pgftello64(stream)
 #else
 #ifndef fseeko
 #define fseeko(stream, offset, origin) fseeko64(stream, offset, origin)
diff --git a/src/port/meson.build b/src/port/meson.build
index b174b25..3d8eeb4 100644
--- a/src/port/meson.build
+++ b/src/port/meson.build
@@ -33,6 +33,7 @@ if host_system == 'windows'
     'win32env.c',
     'win32error.c',
     'win32fdatasync.c',
+    'win32fseek.c',
     'win32getrusage.c',
     'win32link.c',
     'win32ntdll.c',
diff --git a/src/port/win32fseek.c b/src/port/win32fseek.c
new file mode 100644
index 0000000..6cf62db
--- /dev/null
+++ b/src/port/win32fseek.c
@@ -0,0 +1,68 @@
+/*-------------------------------------------------------------------------
+ *
+ * win32fseek.c
+ *	  Replacements for fseeko() and ftello().
+ *
+ * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *	  src/port/win32fseek.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifdef FRONTEND
+#include "postgres_fe.h"
+#else
+#include "postgres.h"
+#endif
+
+#if defined(WIN32) && defined(_MSC_VER)
+
+/*
+ * _pgfseeko64
+ *
+ * Calling fseek() on a handle to a non-seeking device such as a pipe or
+ * a communications device is not supported, even though the fseek() may
+ * not return an error.
+ */
+int
+_pgfseeko64(FILE *stream, pgoff_t offset, int origin)
+{
+	DWORD			fileType;
+
+	fileType = GetFileType((HANDLE) _get_osfhandle(_fileno(stream)));
+
+	if (fileType == FILE_TYPE_DISK)
+		return _fseeki64(stream, offset, origin);
+	else if (fileType == FILE_TYPE_CHAR || fileType == FILE_TYPE_PIPE)
+		errno = ESPIPE;
+	else
+		errno = EINVAL;
+
+	return -1;
+}
+
+/*
+ * _pgftello64
+ *
+ * Same as _pgfseeko64().
+ */
+pgoff_t
+_pgftello64(FILE *stream)
+{
+	DWORD			fileType;
+
+	fileType = GetFileType((HANDLE) _get_osfhandle(_fileno(stream)));
+
+	if (fileType == FILE_TYPE_DISK)
+		return _ftelli64(stream);
+	else if (fileType == FILE_TYPE_CHAR || fileType == FILE_TYPE_PIPE)
+		errno = ESPIPE;
+	else
+		errno = EINVAL;
+
+	return -1;
+}
+
+#endif							/* defined(WIN32) && defined(_MSC_VER) */
diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm
index f1c9ddf..61ace57 100644
--- a/src/tools/msvc/Mkvcbuild.pm
+++ b/src/tools/msvc/Mkvcbuild.pm
@@ -111,6 +111,7 @@ sub mkvcbuild
 	  win32dlopen.c
 	  win32env.c win32error.c
 	  win32fdatasync.c
+	  win32fseek.c
 	  win32getrusage.c
 	  win32gettimeofday.c
 	  win32link.c
-- 
2.11.0

From 3e778828a58751a0b562908176dcb76cabcc7945 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Sun, 19 Mar 2023 20:40:22 +0900
Subject: [PATCH v3] fix fseek detection of unseekable files for WIN32

Calling fseek() on a handle to a non-seeking device such as a pipe or
a communications device is not supported, even though the fseek() may
not return an error, so harden that funcion with our version.
---
 src/include/port/win32_port.h | 12 ++++--
 src/port/meson.build          |  2 +
 src/port/win32common.c        | 68 ++++++++++++++++++++++++++++++++
 src/port/win32fseek.c         | 74 +++++++++++++++++++++++++++++++++++
 src/port/win32stat.c          | 22 ++---------
 configure                     |  6 +++
 configure.ac                  |  1 +
 src/tools/msvc/Mkvcbuild.pm   |  2 +
 8 files changed, 165 insertions(+), 22 deletions(-)
 create mode 100644 src/port/win32common.c
 create mode 100644 src/port/win32fseek.c

diff --git a/src/include/port/win32_port.h b/src/include/port/win32_port.h
index 5116c2fc06..19206ce922 100644
--- a/src/include/port/win32_port.h
+++ b/src/include/port/win32_port.h
@@ -204,15 +204,21 @@ struct itimerval
 
 int			setitimer(int which, const struct itimerval *value, struct itimerval *ovalue);
 
+/* Convenience wrapper for GetFileType() */
+extern DWORD pgwin32_get_file_type(HANDLE hFile);
+
 /*
  * WIN32 does not provide 64-bit off_t, but does provide the functions operating
- * with 64-bit offsets.
+ * with 64-bit offsets. Also, fseek() might not give an error for unseekable
+ * streams, so harden that function with our version.
  */
 #define pgoff_t __int64
 
 #ifdef _MSC_VER
-#define fseeko(stream, offset, origin) _fseeki64(stream, offset, origin)
-#define ftello(stream) _ftelli64(stream)
+extern int  	_pgfseeko64(FILE *stream, pgoff_t offset, int origin);
+extern pgoff_t	_pgftello64(FILE *stream);
+#define fseeko(stream, offset, origin) _pgfseeko64(stream, offset, origin)
+#define ftello(stream) _pgftello64(stream)
 #else
 #ifndef fseeko
 #define fseeko(stream, offset, origin) fseeko64(stream, offset, origin)
diff --git a/src/port/meson.build b/src/port/meson.build
index b174b25021..24416b9bfc 100644
--- a/src/port/meson.build
+++ b/src/port/meson.build
@@ -29,10 +29,12 @@ if host_system == 'windows'
     'kill.c',
     'open.c',
     'system.c',
+    'win32common.c',
     'win32dlopen.c',
     'win32env.c',
     'win32error.c',
     'win32fdatasync.c',
+    'win32fseek.c',
     'win32getrusage.c',
     'win32link.c',
     'win32ntdll.c',
diff --git a/src/port/win32common.c b/src/port/win32common.c
new file mode 100644
index 0000000000..2fd78f7f93
--- /dev/null
+++ b/src/port/win32common.c
@@ -0,0 +1,68 @@
+/*-------------------------------------------------------------------------
+ *
+ * win32common.c
+ *	  Common routines shared among the win32*.c ports.
+ *
+ * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/port/win32common.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifdef FRONTEND
+#include "postgres_fe.h"
+#else
+#include "postgres.h"
+#endif
+
+#ifdef WIN32
+
+/*
+ * pgwin32_get_file_type
+ *
+ * Convenience wrapper for GetFileType() with specific error handling for all the
+ * port implementations.  Returns the file type associated with a HANDLE.
+ *
+ * On error, sets errno with FILE_TYPE_UNKNOWN as file type.
+ */
+DWORD
+pgwin32_get_file_type(HANDLE hFile)
+{
+	DWORD		fileType = FILE_TYPE_UNKNOWN;
+	DWORD		lastError;
+
+	errno = 0;
+
+	/*
+	 * When stdin, stdout, and stderr aren't associated with a stream the
+	 * special value -2 is returned:
+	 * https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/get-osfhandle
+	 */
+	if (hFile == INVALID_HANDLE_VALUE || hFile == (HANDLE) -2)
+	{
+		errno = EINVAL;
+		return FILE_TYPE_UNKNOWN;
+	}
+
+	fileType = GetFileType(hFile);
+	lastError = GetLastError();
+
+	/*
+	 * Invoke GetLastError in order to distinguish between a "valid" return of
+	 * FILE_TYPE_UNKNOWN and its return due to a calling error.  In case of
+	 * success, GetLastError() returns NO_ERROR.
+	 */
+	if (fileType == FILE_TYPE_UNKNOWN && lastError != NO_ERROR)
+	{
+		_dosmaperr(lastError);
+		return FILE_TYPE_UNKNOWN;
+	}
+
+	return fileType;
+}
+
+#endif							/* WIN32 */
diff --git a/src/port/win32fseek.c b/src/port/win32fseek.c
new file mode 100644
index 0000000000..85545c1f09
--- /dev/null
+++ b/src/port/win32fseek.c
@@ -0,0 +1,74 @@
+/*-------------------------------------------------------------------------
+ *
+ * win32fseek.c
+ *	  Replacements for fseeko() and ftello().
+ *
+ * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *	  src/port/win32fseek.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifdef FRONTEND
+#include "postgres_fe.h"
+#else
+#include "postgres.h"
+#endif
+
+#if defined(WIN32) && defined(_MSC_VER)
+
+/*
+ * _pgfseeko64
+ *
+ * Calling fseek() on a handle to a non-seeking device such as a pipe or
+ * a communications device is not supported, even though the fseek() may
+ * not return an error.
+ */
+int
+_pgfseeko64(FILE *stream, pgoff_t offset, int origin)
+{
+	DWORD			fileType;
+	HANDLE			hFile = (HANDLE) _get_osfhandle(_fileno(stream));
+
+	fileType = pgwin32_get_file_type(hFile);
+	if (errno != 0)
+		return -1;
+
+	if (fileType == FILE_TYPE_DISK)
+		return _fseeki64(stream, offset, origin);
+	else if (fileType == FILE_TYPE_CHAR || fileType == FILE_TYPE_PIPE)
+		errno = ESPIPE;
+	else
+		errno = EINVAL;
+
+	return -1;
+}
+
+/*
+ * _pgftello64
+ *
+ * Same as _pgfseeko64().
+ */
+pgoff_t
+_pgftello64(FILE *stream)
+{
+	DWORD			fileType;
+	HANDLE			hFile = (HANDLE) _get_osfhandle(_fileno(stream));
+
+	fileType = pgwin32_get_file_type(hFile);
+	if (errno != 0)
+		return -1;
+
+	if (fileType == FILE_TYPE_DISK)
+		return _ftelli64(stream);
+	else if (fileType == FILE_TYPE_CHAR || fileType == FILE_TYPE_PIPE)
+		errno = ESPIPE;
+	else
+		errno = EINVAL;
+
+	return -1;
+}
+
+#endif							/* defined(WIN32) && defined(_MSC_VER) */
diff --git a/src/port/win32stat.c b/src/port/win32stat.c
index b79da738b2..aa3a0c174e 100644
--- a/src/port/win32stat.c
+++ b/src/port/win32stat.c
@@ -258,33 +258,17 @@ _pgfstat64(int fileno, struct stat *buf)
 {
 	HANDLE		hFile = (HANDLE) _get_osfhandle(fileno);
 	DWORD		fileType = FILE_TYPE_UNKNOWN;
-	DWORD		lastError;
 	unsigned short st_mode;
 
-	/*
-	 * When stdin, stdout, and stderr aren't associated with a stream the
-	 * special value -2 is returned:
-	 * https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/get-osfhandle
-	 */
-	if (hFile == INVALID_HANDLE_VALUE || hFile == (HANDLE) -2 || buf == NULL)
+	if (buf == NULL)
 	{
 		errno = EINVAL;
 		return -1;
 	}
 
-	fileType = GetFileType(hFile);
-	lastError = GetLastError();
-
-	/*
-	 * Invoke GetLastError in order to distinguish between a "valid" return of
-	 * FILE_TYPE_UNKNOWN and its return due to a calling error.  In case of
-	 * success, GetLastError returns NO_ERROR.
-	 */
-	if (fileType == FILE_TYPE_UNKNOWN && lastError != NO_ERROR)
-	{
-		_dosmaperr(lastError);
+	fileType = pgwin32_get_file_type(hFile);
+	if (errno != 0)
 		return -1;
-	}
 
 	switch (fileType)
 	{
diff --git a/configure b/configure
index e221dd5b0f..ded18a0ead 100755
--- a/configure
+++ b/configure
@@ -16490,6 +16490,12 @@ esac
  ;;
 esac
 
+  case " $LIBOBJS " in
+  *" win32common.$ac_objext "* ) ;;
+  *) LIBOBJS="$LIBOBJS win32common.$ac_objext"
+ ;;
+esac
+
   case " $LIBOBJS " in
   *" win32dlopen.$ac_objext "* ) ;;
   *) LIBOBJS="$LIBOBJS win32dlopen.$ac_objext"
diff --git a/configure.ac b/configure.ac
index 3aa6c15c13..7f6620a364 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1893,6 +1893,7 @@ if test "$PORTNAME" = "win32"; then
   AC_LIBOBJ(kill)
   AC_LIBOBJ(open)
   AC_LIBOBJ(system)
+  AC_LIBOBJ(win32common)
   AC_LIBOBJ(win32dlopen)
   AC_LIBOBJ(win32env)
   AC_LIBOBJ(win32error)
diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm
index e3ffc653e5..24599feb33 100644
--- a/src/tools/msvc/Mkvcbuild.pm
+++ b/src/tools/msvc/Mkvcbuild.pm
@@ -108,9 +108,11 @@ sub mkvcbuild
 	  pg_strong_random.c pgcheckdir.c pgmkdirp.c pgsleep.c pgstrcasecmp.c
 	  pqsignal.c mkdtemp.c qsort.c qsort_arg.c bsearch_arg.c quotes.c system.c
 	  strerror.c tar.c
+	  win32common.c
 	  win32dlopen.c
 	  win32env.c win32error.c
 	  win32fdatasync.c
+	  win32fseek.c
 	  win32getrusage.c
 	  win32gettimeofday.c
 	  win32link.c
-- 
2.39.2

From 6ce0e6c996d263d1d9d7348e55756445c80daf2d Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Tue, 11 Apr 2023 14:33:29 +0900
Subject: [PATCH v4] fix fseek detection of unseekable files for WIN32

Calling fseek() on a handle to a non-seeking device such as a pipe or
a communications device is not supported, even though the fseek() may
not return an error, so harden that funcion with our version.
---
 src/include/port/win32_port.h | 12 ++++--
 src/port/meson.build          |  2 +
 src/port/win32common.c        | 68 +++++++++++++++++++++++++++++++
 src/port/win32fseek.c         | 75 +++++++++++++++++++++++++++++++++++
 src/port/win32stat.c          | 22 ++--------
 configure                     |  6 +++
 configure.ac                  |  1 +
 src/tools/msvc/Mkvcbuild.pm   |  2 +
 8 files changed, 166 insertions(+), 22 deletions(-)
 create mode 100644 src/port/win32common.c
 create mode 100644 src/port/win32fseek.c

diff --git a/src/include/port/win32_port.h b/src/include/port/win32_port.h
index 5116c2fc06..58965e0dfd 100644
--- a/src/include/port/win32_port.h
+++ b/src/include/port/win32_port.h
@@ -204,15 +204,21 @@ struct itimerval
 
 int			setitimer(int which, const struct itimerval *value, struct itimerval *ovalue);
 
+/* Convenience wrapper for GetFileType() */
+extern DWORD pgwin32_get_file_type(HANDLE hFile);
+
 /*
  * WIN32 does not provide 64-bit off_t, but does provide the functions operating
- * with 64-bit offsets.
+ * with 64-bit offsets.  Also, fseek() might not give an error for unseekable
+ * streams, so harden that function with our version.
  */
 #define pgoff_t __int64
 
 #ifdef _MSC_VER
-#define fseeko(stream, offset, origin) _fseeki64(stream, offset, origin)
-#define ftello(stream) _ftelli64(stream)
+extern int	_pgfseeko64(FILE *stream, pgoff_t offset, int origin);
+extern pgoff_t _pgftello64(FILE *stream);
+#define fseeko(stream, offset, origin) _pgfseeko64(stream, offset, origin)
+#define ftello(stream) _pgftello64(stream)
 #else
 #ifndef fseeko
 #define fseeko(stream, offset, origin) fseeko64(stream, offset, origin)
diff --git a/src/port/meson.build b/src/port/meson.build
index b174b25021..24416b9bfc 100644
--- a/src/port/meson.build
+++ b/src/port/meson.build
@@ -29,10 +29,12 @@ if host_system == 'windows'
     'kill.c',
     'open.c',
     'system.c',
+    'win32common.c',
     'win32dlopen.c',
     'win32env.c',
     'win32error.c',
     'win32fdatasync.c',
+    'win32fseek.c',
     'win32getrusage.c',
     'win32link.c',
     'win32ntdll.c',
diff --git a/src/port/win32common.c b/src/port/win32common.c
new file mode 100644
index 0000000000..2fd78f7f93
--- /dev/null
+++ b/src/port/win32common.c
@@ -0,0 +1,68 @@
+/*-------------------------------------------------------------------------
+ *
+ * win32common.c
+ *	  Common routines shared among the win32*.c ports.
+ *
+ * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/port/win32common.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifdef FRONTEND
+#include "postgres_fe.h"
+#else
+#include "postgres.h"
+#endif
+
+#ifdef WIN32
+
+/*
+ * pgwin32_get_file_type
+ *
+ * Convenience wrapper for GetFileType() with specific error handling for all the
+ * port implementations.  Returns the file type associated with a HANDLE.
+ *
+ * On error, sets errno with FILE_TYPE_UNKNOWN as file type.
+ */
+DWORD
+pgwin32_get_file_type(HANDLE hFile)
+{
+	DWORD		fileType = FILE_TYPE_UNKNOWN;
+	DWORD		lastError;
+
+	errno = 0;
+
+	/*
+	 * When stdin, stdout, and stderr aren't associated with a stream the
+	 * special value -2 is returned:
+	 * https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/get-osfhandle
+	 */
+	if (hFile == INVALID_HANDLE_VALUE || hFile == (HANDLE) -2)
+	{
+		errno = EINVAL;
+		return FILE_TYPE_UNKNOWN;
+	}
+
+	fileType = GetFileType(hFile);
+	lastError = GetLastError();
+
+	/*
+	 * Invoke GetLastError in order to distinguish between a "valid" return of
+	 * FILE_TYPE_UNKNOWN and its return due to a calling error.  In case of
+	 * success, GetLastError() returns NO_ERROR.
+	 */
+	if (fileType == FILE_TYPE_UNKNOWN && lastError != NO_ERROR)
+	{
+		_dosmaperr(lastError);
+		return FILE_TYPE_UNKNOWN;
+	}
+
+	return fileType;
+}
+
+#endif							/* WIN32 */
diff --git a/src/port/win32fseek.c b/src/port/win32fseek.c
new file mode 100644
index 0000000000..985313c825
--- /dev/null
+++ b/src/port/win32fseek.c
@@ -0,0 +1,75 @@
+/*-------------------------------------------------------------------------
+ *
+ * win32fseek.c
+ *	  Replacements for fseeko() and ftello().
+ *
+ * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *	  src/port/win32fseek.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifdef FRONTEND
+#include "postgres_fe.h"
+#else
+#include "postgres.h"
+#endif
+
+#if defined(WIN32) && defined(_MSC_VER)
+
+/*
+ * _pgfseeko64
+ *
+ * Calling fseek() on a handle to a non-seeking device such as a pipe or
+ * a communications device is not supported, and fseek() may not return
+ * an error.  This wrapper relies on the file type to check which cases
+ * are supported.
+ */
+int
+_pgfseeko64(FILE *stream, pgoff_t offset, int origin)
+{
+	DWORD		fileType;
+	HANDLE		hFile = (HANDLE) _get_osfhandle(_fileno(stream));
+
+	fileType = pgwin32_get_file_type(hFile);
+	if (errno != 0)
+		return -1;
+
+	if (fileType == FILE_TYPE_DISK)
+		return _fseeki64(stream, offset, origin);
+	else if (fileType == FILE_TYPE_CHAR || fileType == FILE_TYPE_PIPE)
+		errno = ESPIPE;
+	else
+		errno = EINVAL;
+
+	return -1;
+}
+
+/*
+ * _pgftello64
+ *
+ * Same as _pgfseeko64().
+ */
+pgoff_t
+_pgftello64(FILE *stream)
+{
+	DWORD		fileType;
+	HANDLE		hFile = (HANDLE) _get_osfhandle(_fileno(stream));
+
+	fileType = pgwin32_get_file_type(hFile);
+	if (errno != 0)
+		return -1;
+
+	if (fileType == FILE_TYPE_DISK)
+		return _ftelli64(stream);
+	else if (fileType == FILE_TYPE_CHAR || fileType == FILE_TYPE_PIPE)
+		errno = ESPIPE;
+	else
+		errno = EINVAL;
+
+	return -1;
+}
+
+#endif							/* defined(WIN32) && defined(_MSC_VER) */
diff --git a/src/port/win32stat.c b/src/port/win32stat.c
index b79da738b2..aa3a0c174e 100644
--- a/src/port/win32stat.c
+++ b/src/port/win32stat.c
@@ -258,33 +258,17 @@ _pgfstat64(int fileno, struct stat *buf)
 {
 	HANDLE		hFile = (HANDLE) _get_osfhandle(fileno);
 	DWORD		fileType = FILE_TYPE_UNKNOWN;
-	DWORD		lastError;
 	unsigned short st_mode;
 
-	/*
-	 * When stdin, stdout, and stderr aren't associated with a stream the
-	 * special value -2 is returned:
-	 * https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/get-osfhandle
-	 */
-	if (hFile == INVALID_HANDLE_VALUE || hFile == (HANDLE) -2 || buf == NULL)
+	if (buf == NULL)
 	{
 		errno = EINVAL;
 		return -1;
 	}
 
-	fileType = GetFileType(hFile);
-	lastError = GetLastError();
-
-	/*
-	 * Invoke GetLastError in order to distinguish between a "valid" return of
-	 * FILE_TYPE_UNKNOWN and its return due to a calling error.  In case of
-	 * success, GetLastError returns NO_ERROR.
-	 */
-	if (fileType == FILE_TYPE_UNKNOWN && lastError != NO_ERROR)
-	{
-		_dosmaperr(lastError);
+	fileType = pgwin32_get_file_type(hFile);
+	if (errno != 0)
 		return -1;
-	}
 
 	switch (fileType)
 	{
diff --git a/configure b/configure
index 905be9568b..dbea7eaf5f 100755
--- a/configure
+++ b/configure
@@ -16492,6 +16492,12 @@ esac
  ;;
 esac
 
+  case " $LIBOBJS " in
+  *" win32common.$ac_objext "* ) ;;
+  *) LIBOBJS="$LIBOBJS win32common.$ac_objext"
+ ;;
+esac
+
   case " $LIBOBJS " in
   *" win32dlopen.$ac_objext "* ) ;;
   *) LIBOBJS="$LIBOBJS win32dlopen.$ac_objext"
diff --git a/configure.ac b/configure.ac
index 8095dfcf1d..dda34304db 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1894,6 +1894,7 @@ if test "$PORTNAME" = "win32"; then
   AC_LIBOBJ(kill)
   AC_LIBOBJ(open)
   AC_LIBOBJ(system)
+  AC_LIBOBJ(win32common)
   AC_LIBOBJ(win32dlopen)
   AC_LIBOBJ(win32env)
   AC_LIBOBJ(win32error)
diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm
index 3d1e0041b2..958206f315 100644
--- a/src/tools/msvc/Mkvcbuild.pm
+++ b/src/tools/msvc/Mkvcbuild.pm
@@ -108,9 +108,11 @@ sub mkvcbuild
 	  pg_strong_random.c pgcheckdir.c pgmkdirp.c pgsleep.c pgstrcasecmp.c
 	  pqsignal.c mkdtemp.c qsort.c qsort_arg.c bsearch_arg.c quotes.c system.c
 	  strerror.c tar.c
+	  win32common.c
 	  win32dlopen.c
 	  win32env.c win32error.c
 	  win32fdatasync.c
+	  win32fseek.c
 	  win32getrusage.c
 	  win32gettimeofday.c
 	  win32link.c
-- 
2.40.0