Preparation for the faster (bulk) LocalFile.childInfos() implementation

resources/bundles/org.eclipse.core.filesystem/src/org/eclipse/core/internal/filesystem/local/LocalFile.java

@@ -135,10 +135,14 @@ private void checkTargetIsNotWritable(File target, Throwable exception) throws C
 		}
 	}
 
+	@Override
+	public IFileInfo[] childInfos(int options, IProgressMonitor monitor) {
+		return LocalFileNativesManager.listDirectoryAndGetFileInfos(filePath);
+	}
+
 	@Override
 	public String[] childNames(int options, IProgressMonitor monitor) {
-		String[] names = file.list();
-		return (names == null ? EMPTY_STRING_ARRAY : names);
+		return LocalFileNativesManager.listDirectoryNames(filePath);
 	}
 
 	@Override

resources/bundles/org.eclipse.core.filesystem/src/org/eclipse/core/internal/filesystem/local/LocalFileNativesManager.java

@@ -87,4 +87,12 @@ public static boolean putFileInfo(String fileName, IFileInfo info, int options)
 		return HANDLER.putFileInfo(fileName, info, options);
 	}
 
+	public static IFileInfo[] listDirectoryAndGetFileInfos(String fileName) {
+		return HANDLER.listDirectoryAndGetFileInfos(fileName);
+	}
+
+	public static String[] listDirectoryNames(String fileName) {
+		return HANDLER.listDirectoryNames(fileName);
+	}
+
 }

resources/bundles/org.eclipse.core.filesystem/src/org/eclipse/core/internal/filesystem/local/NativeHandler.java

@@ -13,6 +13,7 @@
  *******************************************************************************/
 package org.eclipse.core.internal.filesystem.local;
 
+import java.io.File;
 import org.eclipse.core.filesystem.IFileInfo;
 import org.eclipse.core.filesystem.provider.FileInfo;
 
@@ -25,4 +26,21 @@ public abstract class NativeHandler {
 	public abstract FileInfo fetchFileInfo(String fileName);
 
 	public abstract boolean putFileInfo(String fileName, IFileInfo info, int options);
+
+	protected static final String[] EMPTY_STRING_ARRAY = {};
+
+	public String[] listDirectoryNames(String fileName) {
+		String[] names = new File(fileName).list();
+		return names == null ? EMPTY_STRING_ARRAY : names;
+	}
+
+	public IFileInfo[] listDirectoryAndGetFileInfos(String fileName) {
+		var directoryContents = listDirectoryNames(fileName);
+		var result = new IFileInfo[directoryContents.length];
+		for (int i = 0; i < directoryContents.length; i++) {
+			result[i] = fetchFileInfo(fileName + File.separator + directoryContents[i]);
+		}
+		return result;
+	}
+
 }

resources/bundles/org.eclipse.core.filesystem/src/org/eclipse/core/internal/filesystem/local/unix/StructStat.java

@@ -14,13 +14,16 @@
 package org.eclipse.core.internal.filesystem.local.unix;
 
 import org.eclipse.core.filesystem.EFS;
+import org.eclipse.core.filesystem.IFileInfo;
 import org.eclipse.core.filesystem.provider.FileInfo;
 
 /**
  * This class mirrors relevant fields of native struct stat
  * and is used by JNI calls wrapping OS file related functions.
  */
 public class StructStat {
+	/**  errno value for "No such file or directory" */
+	public static final int ENOENT = 2;
 
 	private static final boolean USE_MILLISECOND_RESOLUTION = Boolean.parseBoolean(System.getProperty("eclipse.filesystem.useNatives.modificationTimestampMillisecondsResolution", "true")); //$NON-NLS-1$ //$NON-NLS-2$
 
@@ -29,10 +32,20 @@ public class StructStat {
 	public long st_mtime;
 	public long st_mtime_msec; // millisecond component of the file timestamp, filled on Linux systems
 	public long st_flags; // Filled only on Mac OS X
+	public int errno;
+	public String name;
+	public String linkFile; // Filled target for symbolic links
 
 	public FileInfo toFileInfo() {
 		FileInfo info = new FileInfo();
-		info.setExists(true);
+		if (errno != 0 && errno != ENOENT) {
+			info.setError(IFileInfo.IO_ERROR);
+			return info;
+		}
+		info.setExists(errno != ENOENT);
+		if (name != null) {
+			info.setName(name);
+		}
 		info.setLength(st_size);
 		long lastModified = (st_mtime * 1_000);
 		if (USE_MILLISECOND_RESOLUTION) {
@@ -42,6 +55,12 @@ public FileInfo toFileInfo() {
 		if ((st_mode & UnixFileFlags.S_IFMT) == UnixFileFlags.S_IFDIR) {
 			info.setDirectory(true);
 		}
+		if (linkFile != null) {
+			info.setAttribute(EFS.ATTRIBUTE_SYMLINK, true);
+			if (!linkFile.isEmpty()) {
+				info.setStringAttribute(EFS.ATTRIBUTE_LINK_TARGET, linkFile);
+			}
+		}
 		if ((st_flags & (UnixFileFlags.UF_IMMUTABLE | UnixFileFlags.SF_IMMUTABLE)) != 0) {
 			info.setAttribute(EFS.ATTRIBUTE_IMMUTABLE, true);
 		}

resources/bundles/org.eclipse.core.filesystem/src/org/eclipse/core/internal/filesystem/local/unix/UnixFileNatives.java

@@ -21,7 +21,9 @@
 import org.eclipse.core.filesystem.EFS;
 import org.eclipse.core.filesystem.IFileInfo;
 import org.eclipse.core.filesystem.provider.FileInfo;
-import org.eclipse.core.internal.filesystem.*;
+import org.eclipse.core.internal.filesystem.FileSystemAccess;
+import org.eclipse.core.internal.filesystem.Messages;
+import org.eclipse.core.internal.filesystem.Policy;
 import org.eclipse.core.internal.filesystem.local.Convert;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.osgi.util.NLS;
@@ -30,7 +32,7 @@ public abstract class UnixFileNatives {
 	private static final String LIBRARY_NAME = "unixfile_1_0_0"; //$NON-NLS-1$
 	private static final int UNICODE_SUPPORTED = 1 << 0;
 	private static final int CHFLAGS_SUPPORTED = 1 << 1;
-	private static final int ENOENT = 2; // errno value for "No such file or directory"
+	private static final int ENOENT = StructStat.ENOENT; // errno value for "No such file or directory"
 
 	private static final boolean usingNatives;
 	private static final int libattr;
@@ -80,23 +82,23 @@ public static FileInfo fetchFileInfo(String fileName) {
 		FileInfo info = null;
 		byte[] name = fileNameToBytes(fileName);
 		StructStat stat = new StructStat();
-		if (lstat(name, stat) == 0) {
-			if ((stat.st_mode & UnixFileFlags.S_IFMT) == UnixFileFlags.S_IFLNK) {
-				if (stat(name, stat) == 0) {
-					info = stat.toFileInfo();
-				} else {
+		if (lstat(name, stat) == 0) { // return information about the link itself if the file is a symbolic link
+			if ((stat.st_mode & UnixFileFlags.S_IFMT) == UnixFileFlags.S_IFLNK) { // it a link!
+				if (stat(name, stat) == 0) { // get the information about the file the link points to
+					info = stat.toFileInfo(); // store the target file stats in info
+				} else { // invalid link target!
 					info = new FileInfo();
 					if (getErrno() != ENOENT) {
 						info.setError(IFileInfo.IO_ERROR);
 					}
 				}
-				info.setAttribute(EFS.ATTRIBUTE_SYMLINK, true);
+				info.setAttribute(EFS.ATTRIBUTE_SYMLINK, true); // set symlink attribute
 				byte target[] = new byte[UnixFileFlags.PATH_MAX];
 				int length = readlink(name, target, target.length);
-				if (length > 0) {
+				if (length > 0) { // set target of the link
 					info.setStringAttribute(EFS.ATTRIBUTE_LINK_TARGET, bytesToFileName(target, length));
 				}
-			} else {
+			} else { // regular file or directory
 				info = stat.toFileInfo();
 			}
 		} else {
@@ -106,7 +108,7 @@ public static FileInfo fetchFileInfo(String fileName) {
 			}
 		}
 
-		if (info.getName() == null) {
+		if (info.getName().isEmpty()) {
 			// If the file system is case insensitive, we don't know the real name of the file.
 			// Since obtaining the real name in such situation is pretty expensive, we use the name
 			// passed as a parameter, which may differ by case from the real name of the file