Implemented option to specify version numbers to install/remove through an expression.

pkgtool.pm

@@ -96,7 +96,22 @@ my $pkgdef_syntax = {
 				Type => 'string'
 			},
 			'patching-version' => {
-				Type => 'string'
+				Type => 'or',
+				Options => [{
+					Type => 'string'
+				}, {
+					Type => 'struct',
+					Check => \&check_cfg_patching_version_struct,
+					Keywords => {
+						'type' => {
+							Type => 'string',
+							Mandatory => 1
+						},
+						'expression' => {
+							Type => 'string'
+						}
+					}
+				}]
 			},
 			'install-check' => {
 				Type => 'string'
@@ -517,10 +532,40 @@ my $global_cfg_syntax = {
 						Type => 'string'
 					},
 					'remove-version' => {
-						Type => 'string'
+						Type => 'or',
+						Options => [{
+							Type => 'string'
+						}, {
+							Type => 'struct',
+							Check => \&check_cfg_remove_version_struct,
+							Keywords => {
+								'type' => {
+									Type => 'string',
+									Mandatory => 1
+								},
+								'expression' => {
+									Type => 'string'
+								}
+							}
+						}]
 					},
 					'install-version' => {
-						Type => 'string'
+						Type => 'or',
+						Options => [{
+							Type => 'string'
+						}, {
+							Type => 'struct',
+							Check => \&check_cfg_install_version_struct,
+							Keywords => {
+								'type' => {
+									Type => 'string',
+									Mandatory => 1
+								},
+								'expression' => {
+									Type => 'string'
+								}
+							}
+						}]
 					},
 					'patch-packages' => {
 						Type => 'list',
@@ -1223,6 +1268,66 @@ sub check_cfg_pkg_version_struct ($$)
 	return 1;
 }
 
+sub check_cfg_patching_version_struct ($$)
+{
+	my ($option, $label) = @_;
+
+	my $type = $$option{type};
+
+	if ($type eq 'expression') {
+		if (! defined $$option{'expression'}) {
+			print_log('pkg', ERROR, 'Package patching version option missing "expression" at %s', $label);
+			return 0;
+		}
+	}
+	else {
+		print_log('pkg', ERROR, 'Unknown package patching version option type at %s', $label.': '.$type);
+		return 0;
+	}
+
+	return 1;
+}
+
+sub check_cfg_install_version_struct ($$)
+{
+	my ($option, $label) = @_;
+
+	my $type = $$option{type};
+
+	if ($type eq 'expression') {
+		if (! defined $$option{'expression'}) {
+			print_log('pkg', ERROR, 'Install version option missing "expression" at %s', $label);
+			return 0;
+		}
+	}
+	else {
+		print_log('pkg', ERROR, 'Unknown install version option type at %s', $label.': '.$type);
+		return 0;
+	}
+
+	return 1;
+}
+
+sub check_cfg_remove_version_struct ($$)
+{
+	my ($option, $label) = @_;
+
+	my $type = $$option{type};
+
+	if ($type eq 'expression') {
+		if (! defined $$option{'expression'}) {
+			print_log('pkg', ERROR, 'Remove version option missing "expression" at %s', $label);
+			return 0;
+		}
+	}
+	else {
+		print_log('pkg', ERROR, 'Unknown remove version option type at %s', $label.': '.$type);
+		return 0;
+	}
+
+	return 1;
+}
+
 sub evaluate_expression ($$$$)
 {
 	my ($channel, $vars, $inst, $expression) = @_;
@@ -2157,6 +2262,30 @@ sub pkgdef_get_desired_version ($$$$$)
 {
 	my ($config, $name, $base_directory, $def, $version) = @_;
 
+	return undef unless defined $version;
+	if (ref($version) eq 'HASH') {
+		my $etype = $$version{type};
+		print_log('global', DEBUG4, 'Evaluating version reference %s in definition %s',
+			$etype, $$def{description});
+		if ($etype eq 'expression') {
+			my $vars = get_default_vars($config);
+			set_datetime_vars($vars);
+			$$vars{pkgname} = $name;
+			my $appdir = substitute_variables($vars, $$def{'source-directory'}, 1, $base_directory, 'pkg');
+			$$vars{appdir} = $appdir;
+
+			my $expression = $$version{expression};
+			my ($value, $error) = evaluate_expression('global', $vars, $def, $expression);
+
+			if (defined $error && $error ne '') {
+				print_log('global', DEBUG4, 'Evaluating version reference expression %s failed: %s',
+					$expression, $error);
+				return undef;
+			}
+			print_log('global', DEBUG4, 'Version reference expression result: %s', defined $value ? $value : '<undef>');
+			$version = $value;
+		}
+	}
 	return undef unless defined $version;
 	my $versions = $$def{'package-versions'};
 	if (defined $versions) {