Print info about locked files during configuration or genSources (#1066)

* Print info about locked files during configuration or genSources

* Use release version

* Output adjustments

* Fix build

* Add user back

build.gradle

@@ -131,11 +131,12 @@ dependencies {
 	implementation libs.fabric.tiny.remapper
 	implementation libs.fabric.access.widener
 	implementation libs.fabric.mapping.io
-
 	implementation (libs.fabric.lorenz.tiny) {
 		transitive = false
 	}
 
+	implementation libs.fabric.loom.nativelib
+
 	// decompilers
 	fernflowerCompileOnly runtimeLibs.fernflower
 	fernflowerCompileOnly libs.fabric.mapping.io

gradle/libs.versions.toml

@@ -12,6 +12,7 @@ mapping-io = "0.5.1"
 lorenz-tiny = "4.0.2"
 mercury = "0.4.1"
 kotlinx-metadata = "0.9.0"
+loom-native = "0.1.0"
 
 # Plugins
 spotless = "6.25.0"
@@ -38,6 +39,7 @@ fabric-access-widener = { module = "net.fabricmc:access-widener", version.ref =
 fabric-mapping-io = { module = "net.fabricmc:mapping-io", version.ref = "mapping-io" }
 fabric-lorenz-tiny = { module = "net.fabricmc:lorenz-tiny", version.ref = "lorenz-tiny" }
 fabric-mercury = { module = "net.fabricmc:mercury", version.ref = "mercury" }
+fabric-loom-nativelib = { module = "net.fabricmc:fabric-loom-native", version.ref = "loom-native" }
 
 # Misc
 kotlin-gradle-plugin = { module = "org.jetbrains.kotlin:kotlin-gradle-plugin", version.ref = "kotlin" }

src/main/java/net/fabricmc/loom/configuration/CompileConfiguration.java

@@ -32,8 +32,6 @@ import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.time.Duration;
-import java.util.ArrayList;
-import java.util.List;
 import java.util.Optional;
 import java.util.function.Consumer;
 
@@ -41,7 +39,6 @@ import javax.inject.Inject;
 
 import org.gradle.api.GradleException;
 import org.gradle.api.Project;
-import org.gradle.api.logging.LogLevel;
 import org.gradle.api.logging.Logger;
 import org.gradle.api.logging.Logging;
 import org.gradle.api.plugins.JavaPlugin;
@@ -72,6 +69,7 @@ import net.fabricmc.loom.configuration.providers.minecraft.mapped.NamedMinecraft
 import net.fabricmc.loom.extension.MixinExtension;
 import net.fabricmc.loom.util.Checksum;
 import net.fabricmc.loom.util.ExceptionUtil;
+import net.fabricmc.loom.util.ProcessUtil;
 import net.fabricmc.loom.util.gradle.GradleUtils;
 import net.fabricmc.loom.util.gradle.SourceSetHelper;
 import net.fabricmc.loom.util.service.ScopedSharedServiceManager;
@@ -110,6 +108,7 @@ public abstract class CompileConfiguration implements Runnable {
 			try {
 				setupMinecraft(configContext);
 			} catch (Exception e) {
+				ExceptionUtil.printFileLocks(e, getProject());
 				throw ExceptionUtil.createDescriptiveWrapper(RuntimeException::new, "Failed to setup Minecraft", e);
 			}
 
@@ -315,7 +314,8 @@ public abstract class CompileConfiguration implements Runnable {
 				Files.deleteIfExists(lockFile.file);
 				abrupt = true;
 			} else {
-				logger.lifecycle(printWithParents(handle.get()));
+				ProcessUtil processUtil = ProcessUtil.create(getProject());
+				logger.lifecycle(processUtil.printWithParents(handle.get()));
 				logger.lifecycle("Waiting for lock to be released...");
 				long sleptMs = 0;
 
@@ -353,69 +353,6 @@ public abstract class CompileConfiguration implements Runnable {
 		return abrupt ? LockResult.ACQUIRED_PREVIOUS_OWNER_MISSING : LockResult.ACQUIRED_CLEAN;
 	}
 
-	private String printWithParents(ProcessHandle processHandle) {
-		var output = new StringBuilder();
-
-		List<ProcessHandle> chain = getParentChain(null, processHandle);
-
-		for (int i = 0; i < chain.size(); i++) {
-			ProcessHandle handle = chain.get(i);
-
-			output.append("\t".repeat(i));
-
-			if (i != 0) {
-				output.append("└─ ");
-			}
-
-			output.append(getInfoString(handle));
-
-			if (i < chain.size() - 1) {
-				output.append('\n');
-			}
-		}
-
-		return output.toString();
-	}
-
-	private String getInfoString(ProcessHandle handle) {
-		return "(%s) pid %s '%s%s'%s".formatted(
-				handle.info().user().orElse("unknown user"),
-				handle.pid(),
-				handle.info().command().orElse("unknown command"),
-				handle.info().arguments().map(arr -> {
-					if (getProject().getGradle().getStartParameter().getLogLevel() != LogLevel.INFO
-							&& getProject().getGradle().getStartParameter().getLogLevel() != LogLevel.DEBUG) {
-						return " (run with --info or --debug to show arguments, may reveal sensitive info)";
-					}
-
-					String join = String.join(" ", arr);
-
-					if (join.isBlank()) {
-						return "";
-					}
-
-					return " " + join;
-				}).orElse(" (unknown arguments)"),
-				handle.info().startInstant().map(instant -> " started at " + instant).orElse("")
-		);
-	}
-
-	private List<ProcessHandle> getParentChain(List<ProcessHandle> collectTo, ProcessHandle processHandle) {
-		if (collectTo == null) {
-			collectTo = new ArrayList<>();
-		}
-
-		Optional<ProcessHandle> parent = processHandle.parent();
-
-		if (parent.isPresent()) {
-			getParentChain(collectTo, parent.get());
-		}
-
-		collectTo.add(processHandle);
-
-		return collectTo;
-	}
-
 	private void releaseLock() {
 		final Path lock = getLockFile().file;
 

src/main/java/net/fabricmc/loom/task/GenerateSourcesTask.java

@@ -198,7 +198,8 @@ public abstract class GenerateSourcesTask extends AbstractLoomTask {
 			final var provideContext = new AbstractMappedMinecraftProvider.ProvideContext(false, true, configContext);
 			minecraftJars = getExtension().getNamedMinecraftProvider().provide(provideContext);
 		} catch (Exception e) {
-			throw new RuntimeException("Failed to rebuild input jars", e);
+			ExceptionUtil.printFileLocks(e, getProject());
+			throw ExceptionUtil.createDescriptiveWrapper(RuntimeException::new, "Failed to rebuild input jars", e);
 		}
 
 		for (MinecraftJar minecraftJar : minecraftJars) {

src/main/java/net/fabricmc/loom/util/ExceptionUtil.java

@@ -1,7 +1,7 @@
 /*
  * This file is part of fabric-loom, licensed under the MIT License (MIT).
  *
- * Copyright (c) 2022 FabricMC
+ * Copyright (c) 2022-2024 FabricMC
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -24,8 +24,17 @@
 
 package net.fabricmc.loom.util;
 
+import java.nio.file.FileSystemException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.List;
 import java.util.function.BiFunction;
 
+import org.gradle.api.Project;
+
+import net.fabricmc.loom.nativeplatform.LoomNativePlatform;
+
 public final class ExceptionUtil {
 	/**
 	 * Creates a descriptive user-facing wrapper exception for an underlying cause.
@@ -44,4 +53,40 @@ public final class ExceptionUtil {
 		String descriptiveMessage = "%s, %s: %s".formatted(message, cause.getClass().getName(), cause.getMessage());
 		return constructor.apply(descriptiveMessage, cause);
 	}
+
+	public static void printFileLocks(Throwable e, Project project) {
+		Throwable cause = e;
+
+		while (cause != null) {
+			if (cause instanceof FileSystemException fse) {
+				printFileLocks(fse.getFile(), project);
+				break;
+			}
+
+			cause = cause.getCause();
+		}
+	}
+
+	private static void printFileLocks(String filename, Project project) {
+		final Path path = Paths.get(filename);
+
+		if (!Files.exists(path)) {
+			return;
+		}
+
+		final List<ProcessHandle> processes = LoomNativePlatform.getProcessesWithLockOn(path);
+
+		if (processes.isEmpty()) {
+			return;
+		}
+
+		final ProcessUtil processUtil = ProcessUtil.create(project);
+
+		final String noun = processes.size() == 1 ? "process has" : "processes have";
+		project.getLogger().error("The following {} a lock on the file '{}':", noun, path);
+
+		for (ProcessHandle process : processes) {
+			project.getLogger().error(processUtil.printWithParents(process));
+		}
+	}
 }

src/main/java/net/fabricmc/loom/util/ProcessUtil.java

@@ -0,0 +1,109 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2024 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.util;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.StringJoiner;
+
+import org.gradle.api.Project;
+import org.gradle.api.logging.LogLevel;
+
+import net.fabricmc.loom.nativeplatform.LoomNativePlatform;
+
+public record ProcessUtil(LogLevel logLevel) {
+	private static final String EXPLORER_COMMAND = "C:\\Windows\\explorer.exe";
+
+	public static ProcessUtil create(Project project) {
+		return new ProcessUtil(project.getGradle().getStartParameter().getLogLevel());
+	}
+
+	public String printWithParents(ProcessHandle handle) {
+		String result = printWithParents(handle, 0).trim();
+
+		if (logLevel != LogLevel.INFO && logLevel != LogLevel.DEBUG) {
+			return "Run with --info or --debug to show arguments, may reveal sensitive info\n" + result;
+		}
+
+		return result;
+	}
+
+	private String printWithParents(ProcessHandle handle, int depth) {
+		var lines = new ArrayList<String>();
+		getWindowTitles(handle).ifPresent(titles -> lines.add("title: " + titles));
+		lines.add("pid: " + handle.pid());
+		handle.info().command().ifPresent(command -> lines.add("command: " + command));
+		getProcessArguments(handle).ifPresent(arguments -> lines.add("arguments: " + arguments));
+		handle.info().startInstant().ifPresent(instant -> lines.add("started at: " + instant));
+		handle.info().user().ifPresent(user -> lines.add("user: " + user));
+		handle.parent().ifPresent(parent -> lines.add("parent:\n" + printWithParents(parent, depth + 1)));
+
+		StringBuilder sj = new StringBuilder();
+
+		for (String line : lines) {
+			sj.append("\t".repeat(depth)).append("- ").append(line).append('\n');
+		}
+
+		return sj.toString();
+	}
+
+	private Optional<String> getProcessArguments(ProcessHandle handle) {
+		if (logLevel != LogLevel.INFO && logLevel != LogLevel.DEBUG) {
+			return Optional.empty();
+		}
+
+		return handle.info().arguments().map(arr -> {
+			String join = String.join(" ", arr);
+
+			if (join.isBlank()) {
+				return "";
+			}
+
+			return " " + join;
+		});
+	}
+
+	private Optional<String> getWindowTitles(ProcessHandle processHandle) {
+		if (processHandle.info().command().orElse("").equals(EXPLORER_COMMAND)) {
+			// Explorer is a single process, so the window titles are not useful
+			return Optional.empty();
+		}
+
+		List<String> titles = LoomNativePlatform.getWindowTitlesForPid(processHandle.pid());
+
+		if (titles.isEmpty()) {
+			return Optional.empty();
+		}
+
+		final StringJoiner joiner = new StringJoiner(", ");
+
+		for (String title : titles) {
+			joiner.add("'" + title + "'");
+		}
+
+		return Optional.of(joiner.toString());
+	}
+}

src/test/groovy/net/fabricmc/loom/test/unit/ProcessUtilTest.groovy

@@ -0,0 +1,41 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.test.unit
+
+import org.gradle.api.logging.LogLevel
+import spock.lang.Specification
+
+import net.fabricmc.loom.util.ProcessUtil
+
+class ProcessUtilTest extends Specification {
+	def "print process info"() {
+		when:
+		def output = new ProcessUtil(LogLevel.DEBUG).printWithParents(ProcessHandle.current())
+
+		then:
+		// Just a simple check to see if the output is not empty
+		!output.isEmpty()
+	}
+}