Allow default value for CONF_FOLDER to be set at build time

Closes gh-6549

spring-boot-docs/src/main/asciidoc/deployment.adoc

@@ -608,6 +608,9 @@ for Gradle and to `${project.name}` for Maven.
 |`initInfoChkconfig`
 |The `chkconfig` section of "`INIT INFO`". Defaults to `2345 99 01`.
 
+|`confFolder`
+|The default value for `CONF_FOLDER`. Defaults to the folder containing the jar.
+
 |`logFolder`
 |The default value for `LOG_FOLDER`. Only valid for an `init.d` service.
 

spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/DefaultLaunchScript.java

@@ -42,7 +42,7 @@ public class DefaultLaunchScript implements LaunchScript {
 	private static final int BUFFER_SIZE = 4096;
 
 	private static final Pattern PLACEHOLDER_PATTERN = Pattern
-			.compile("\\{\\{(\\w+)(:.*?)?\\}\\}");
+			.compile("\\{\\{(\\w+)(:.*?)?\\}\\}(?!\\})");
 
 	private final String content;
 
@@ -97,7 +97,7 @@ public class DefaultLaunchScript implements LaunchScript {
 			else {
 				value = (value == null ? matcher.group(0) : value.substring(1));
 			}
-			matcher.appendReplacement(expanded, value);
+			matcher.appendReplacement(expanded, value.replace("$", "\\$"));
 		}
 		matcher.appendTail(expanded);
 		return expanded.toString();

spring-boot-tools/spring-boot-loader-tools/src/main/resources/org/springframework/boot/loader/tools/launch.script

@@ -44,7 +44,7 @@ cd "$WORKING_DIR" || exit 1
 configfile="$(basename "${jarfile%.*}.conf")"
 
 # Initialize CONF_FOLDER location defaulting to jarfolder
-[[ -z "$CONF_FOLDER" ]] && CONF_FOLDER="${jarfolder}"
+[[ -z "$CONF_FOLDER" ]] && CONF_FOLDER="{{confFolder:${jarfolder}}}"
 
 # shellcheck source=/dev/null
 [[ -r "${CONF_FOLDER}/${configfile}" ]] && source "${CONF_FOLDER}/${configfile}"

spring-boot-tools/spring-boot-loader-tools/src/test/java/org/springframework/boot/loader/tools/DefaultLaunchScriptTests.java

@@ -86,6 +86,11 @@ public class DefaultLaunchScriptTests {
 		assertThatPlaceholderCanBeReplaced("pidFolder");
 	}
 
+	@Test
+	public void confFolderCanBeReplaced() throws Exception {
+		assertThatPlaceholderCanBeReplaced("confFolder");
+	}
+
 	@Test
 	public void defaultForUseStartStopDaemonIsTrue() throws Exception {
 		DefaultLaunchScript script = new DefaultLaunchScript(null, null);