Add support for Visual Studio 2019 in build scripts

This fixes at the same time a set of inconsistencies in 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

src/tools/msvc/MSBuildProject.pm

@@ -467,4 +467,29 @@ sub new
 	return $self;
 }
 
+package VC2019Project;
+
+#
+# Package that encapsulates a Visual C++ 2019 project file
+#
+
+use strict;
+use warnings;
+use base qw(MSBuildProject);
+
+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;

src/tools/msvc/README

@@ -4,7 +4,7 @@ MSVC build
 ==========
 
 This directory contains the tools required to build PostgreSQL using
-Microsoft Visual Studio 2013 - 2017. This builds the whole backend, not just
+Microsoft Visual Studio 2013 - 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.
 
@@ -16,7 +16,7 @@ has to be installed. Since this is not included in the product
 originally, extra steps are needed to make it work.
 
 First, download and install a supported version of the Microsoft Windows SDK
-from www.microsoft.com (v6.0 or greater).
+from www.microsoft.com (v8.1a or greater).
 
 Locate the files vcprojectengine.dll.express.config and
 vcprojectengine.dll.config in the vc\vcpackages directory of
@@ -88,11 +88,11 @@ config_default.pl to create the configuration arguments.
 These configuration arguments are passed over to Mkvcbuild::mkvcbuild
 (Mkvcbuild.pm) which creates the Visual Studio project and solution files.
 It does this by using VSObjectFactory::CreateSolution to create an object
-implementing the Solution interface (this could be either 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 (VC2013Project or VC2015Project or VC2017Project from
-MSBuildProject.pm) to it.
+implementing the Solution interface (this could be either VS2013Solution,
+VS2015Solution, VS2017Solution or VS2019Solution, all in Solution.pm,
+depending on the user's build environment) and adding objects implementing
+the corresponding Project interface (VC2013Project, VC2015Project,
+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) is

src/tools/msvc/Solution.pm

@@ -969,6 +969,34 @@ 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) = @_;

src/tools/msvc/VSObjectFactory.pm

@@ -39,16 +39,29 @@ 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.";
 	}
 }
 
@@ -70,16 +83,29 @@ 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.";
 	}
 }
 
@@ -106,17 +132,19 @@ 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)
+	elsif ($major < 12)
 	{
 		croak
-		  "Unable to determine Visual Studio version: Visual Studio versions before 6.0 aren't supported.";
+		  "Unable to determine Visual Studio version: Visual Studio versions before 12.0 aren't supported.";
 	}
 	return "$major.$minor";
 }