Add support for Visual Studio 2019 in build scripts

This adjusts the documentation and the scripts related to the versions
of Windows SDK supported.

Author: Haribabu Kommi
Reviewed-by: Andrew Dunstan, Juan José Santamaría Flecha, Michael
Paquier
Discussion: https://postgr.es/m/CAJrrPGcfqXhfPyMrny9apoDU7M1t59dzVAvoJ9AeAh5BJi+UzA@mail.gmail.com
Backpatch-through: 9.4

4 files changed, 101 insertions, 19 deletions

diff --git a/src/tools/msvc/MSBuildProject.pm b/src/tools/msvc/MSBuildProject.pm
index 47252533a1b..3edb11b9b5f 100644
--- a/src/tools/msvc/MSBuildProject.pm
+++ b/src/tools/msvc/MSBuildProject.pm
@@ -535,4 +535,29 @@ sub new
 	return $self;
 }
 
+package VC2019Project;
+
+#
+# Package that encapsulates a Visual C++ 2019 project file
+#
+
+use strict;
+use warnings;
+use base qw(VC2012Project);
+
+no warnings qw(redefine);    ## no critic
+
+sub new
+{
+	my $classname = shift;
+	my $self      = $classname->SUPER::_new(@_);
+	bless($self, $classname);
+
+	$self->{vcver}           = '16.00';
+	$self->{PlatformToolset} = 'v142';
+	$self->{ToolsVersion}    = '16.0';
+
+	return $self;
+}
+
 1;
diff --git a/src/tools/msvc/README b/src/tools/msvc/README
index 48082cab90a..c6db875730c 100644
--- a/src/tools/msvc/README
+++ b/src/tools/msvc/README
@@ -4,7 +4,7 @@ MSVC build
 ==========
 
 This directory contains the tools required to build PostgreSQL using
-Microsoft Visual Studio 2005 - 2017. This builds the whole backend, not just
+Microsoft Visual Studio 2005 - 2019. This builds the whole backend, not just
 the libpq frontend library. For more information, see the documentation
 chapter "Installation on Windows" and the description below.
 
@@ -93,11 +93,12 @@ These configuration arguments are passed over to Mkvcbuild::mkvcbuild
 It does this by using VSObjectFactory::CreateSolution to create an object
 implementing the Solution interface (this could be either a VS2005Solution,
 a VS2008Solution, a VS2010Solution or a VS2012Solution or a VS2013Solution,
-or a VS2015Solution or a VS2017Solution, all in Solution.pm, depending on
-the user's build environment) and adding objects implementing the corresponding
-Project interface (VC2005Project or VC2008Project from VCBuildProject.pm or
-VC2010Project or VC2012Project or VC2013Project or VC2015Project or VC2017Project
-from MSBuildProject.pm) to it.
+or a VS2015Solution or a VS2017Solution or a VS2019Solution, all in
+Solution.pm, depending on the user's build environment) and adding objects
+implementing the corresponding Project interface (VC2005Project or
+VC2008Project from VCBuildProject.pm or VC2010Project or VC2012Project or
+VC2013Project or VC2015Project or VC2017Project or VC2019Project from
+MSBuildProject.pm) to it.
 When Solution::Save is called, the implementations of Solution and Project
 save their content in the appropriate format.
 The final step of starting the appropriate build program (msbuild or vcbuild)
diff --git a/src/tools/msvc/Solution.pm b/src/tools/msvc/Solution.pm
index 5cf20f9d7a2..c59cfd50238 100644
--- a/src/tools/msvc/Solution.pm
+++ b/src/tools/msvc/Solution.pm
@@ -1037,6 +1037,34 @@ sub new
 	return $self;
 }
 
+package VS2019Solution;
+
+#
+# Package that encapsulates a Visual Studio 2019 solution file
+#
+
+use Carp;
+use strict;
+use warnings;
+use base qw(Solution);
+
+no warnings qw(redefine);    ## no critic
+
+sub new
+{
+	my $classname = shift;
+	my $self      = $classname->SUPER::_new(@_);
+	bless($self, $classname);
+
+	$self->{solutionFileVersion}        = '12.00';
+	$self->{vcver}                      = '16.00';
+	$self->{visualStudioName}           = 'Visual Studio 2019';
+	$self->{VisualStudioVersion}        = '16.0.28729.10';
+	$self->{MinimumVisualStudioVersion} = '10.0.40219.1';
+
+	return $self;
+}
+
 sub GetAdditionalHeaders
 {
 	my ($self, $f) = @_;
diff --git a/src/tools/msvc/VSObjectFactory.pm b/src/tools/msvc/VSObjectFactory.pm
index 92a4fb6841f..73990ede399 100644
--- a/src/tools/msvc/VSObjectFactory.pm
+++ b/src/tools/msvc/VSObjectFactory.pm
@@ -56,16 +56,29 @@ sub CreateSolution
 		return new VS2015Solution(@_);
 	}
 
-	# visual 2017 hasn't changed the nmake version to 15, so adjust the check to support it.
-	elsif (($visualStudioVersion ge '14.10')
-		or ($visualStudioVersion eq '15.00'))
+	# The version of nmake bundled in Visual Studio 2017 is greater
+	# than 14.10 and less than 14.20.  And the version number is
+	# actually 15.00.
+	elsif (
+		($visualStudioVersion ge '14.10' && $visualStudioVersion lt '14.20')
+		|| $visualStudioVersion eq '15.00')
 	{
 		return new VS2017Solution(@_);
 	}
+
+	# The version of nmake bundled in Visual Studio 2019 is greater
+	# than 14.20 and less than 14.30.  And the version number is
+	# actually 16.00.
+	elsif (
+		($visualStudioVersion ge '14.20' && $visualStudioVersion lt '14.30')
+		|| $visualStudioVersion eq '16.00')
+	{
+		return new VS2019Solution(@_);
+	}
 	else
 	{
-		croak $visualStudioVersion;
-		croak "The requested Visual Studio version is not supported.";
+		croak
+		  "The requested Visual Studio version $visualStudioVersion is not supported.";
 	}
 }
 
@@ -103,16 +116,29 @@ sub CreateProject
 		return new VC2015Project(@_);
 	}
 
-	# visual 2017 hasn't changed the nmake version to 15, so adjust the check to support it.
-	elsif (($visualStudioVersion ge '14.10')
-		or ($visualStudioVersion eq '15.00'))
+	# The version of nmake bundled in Visual Studio 2017 is greater
+	# than 14.10 and less than 14.20.  And the version number is
+	# actually 15.00.
+	elsif (
+		($visualStudioVersion ge '14.10' && $visualStudioVersion lt '14.20')
+		|| $visualStudioVersion eq '15.00')
 	{
 		return new VC2017Project(@_);
 	}
+
+	# The version of nmake bundled in Visual Studio 2019 is greater
+	# than 14.20 and less than 14.30.  And the version number is
+	# actually 16.00.
+	elsif (
+		($visualStudioVersion ge '14.20' && $visualStudioVersion lt '14.30')
+		|| $visualStudioVersion eq '16.00')
+	{
+		return new VC2019Project(@_);
+	}
 	else
 	{
-		croak $visualStudioVersion;
-		croak "The requested Visual Studio version is not supported.";
+		croak
+		  "The requested Visual Studio version $visualStudioVersion is not supported.";
 	}
 }
 
@@ -139,12 +165,14 @@ sub _GetVisualStudioVersion
 {
 	my ($major, $minor) = @_;
 
-	# visual 2017 hasn't changed the nmake version to 15, so still using the older version for comparison.
-	if ($major > 14)
+	# The major visual studio that is supported has nmake
+	# version <= 14.30, so stick with it as the latest version
+	# if bumping on something even newer.
+	if ($major >= 14 && $minor >= 30)
 	{
 		carp
 		  "The determined version of Visual Studio is newer than the latest supported version. Returning the latest supported version instead.";
-		return '14.00';
+		return '14.20';
 	}
 	elsif ($major < 6)
 	{