devonfw#132: untar preserves unix file permissios

also wrote a test for untar.
Unzip still does not preserve file permissions

cli/src/main/java/com/devonfw/tools/ide/io/FileAccess.java

@@ -1,5 +1,6 @@
 package com.devonfw.tools.ide.io;
 
+import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
 import java.nio.file.Path;
 import java.util.function.Predicate;
 
@@ -62,7 +63,7 @@ public interface FileAccess {
    * Creates a symbolic link. If the given {@code targetLink} already exists and is a symbolic link or a Windows
    * junction, it will be replaced. In case of missing privileges, Windows Junctions may be used as fallback, which must
    * point to absolute paths. Therefore, the created link will be absolute instead of relative.
-   * 
+   *
    * @param source the source {@link Path} to link to, may be relative or absolute.
    * @param targetLink the {@link Path} where the symbolic link shall be created pointing to {@code source}.
    * @param relative - {@code true} if the symbolic link shall be relative, {@code false} if it shall be absolute.
@@ -73,7 +74,7 @@ public interface FileAccess {
    * Creates a relative symbolic link. If the given {@code targetLink} already exists and is a symbolic link or a
    * Windows junction, it will be replaced. In case of missing privileges, Windows Junctions may be used as fallback,
    * which must point to absolute paths. Therefore, the created link will be absolute instead of relative.
-   * 
+   *
    * @param source the source {@link Path} to link to, may be relative or absolute.
    * @param targetLink the {@link Path} where the symbolic link shall be created pointing to {@code source}.
    */
@@ -124,6 +125,13 @@ default void copy(Path source, Path target) {
    */
   Path toRealPath(Path path);
 
+  /**
+   * @param permissionInt The integer as returned by {@link TarArchiveEntry#getMode()} that represents the file
+   *        permissions of a file on a Unix file system.
+   * @return A String representing the file permissions. E.g. "rwxrwxr-x" or "rw-rw-r--"
+   */
+  String generatePermissionString(int permissionInt);
+
   /**
    * Deletes the given {@link Path} idempotent and recursive.
    *

cli/src/main/java/com/devonfw/tools/ide/io/FileAccessImpl.java

@@ -18,20 +18,25 @@
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.nio.file.attribute.BasicFileAttributes;
+import java.nio.file.attribute.PosixFilePermission;
+import java.nio.file.attribute.PosixFilePermissions;
 import java.security.DigestInputStream;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.time.LocalDateTime;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Set;
 import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.stream.Stream;
 
 import org.apache.commons.compress.archivers.ArchiveEntry;
 import org.apache.commons.compress.archivers.ArchiveInputStream;
+import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
 import org.apache.commons.compress.archivers.tar.TarArchiveInputStream;
+import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
 import org.apache.commons.compress.archivers.zip.ZipArchiveInputStream;
 
 import com.devonfw.tools.ide.context.IdeContext;
@@ -315,8 +320,7 @@ private void deleteLinkIfExists(Path path) throws IOException {
         return;
       }
     }
-    exists = exists || Files.exists(path); // "||" since broken junctions are not detected by
-                                           // Files.exists(brokenJunction)
+    exists = exists || Files.exists(path);
     boolean isSymlink = exists && Files.isSymbolicLink(path);
 
     assert !(isSymlink && isJunction);
@@ -378,7 +382,7 @@ private Path adaptPath(Path source, Path targetLink, boolean relative) throws IO
 
   /**
    * Creates a Windows junction at {@code targetLink} pointing to {@code source}.
-   * 
+   *
    * @param source must be another Windows junction or a directory.
    * @param targetLink the location of the Windows junction.
    */
@@ -495,12 +499,44 @@ public void untar(Path file, Path targetDir, TarCompression compression) {
     unpack(file, targetDir, in -> new TarArchiveInputStream(compression.unpack(in)));
   }
 
+  public String generatePermissionString(int permissions) {
+
+    // Ensure that only the last 9 bits are considered
+    permissions &= 0b111111111;
+
+    StringBuilder permissionStringBuilder = new StringBuilder("rwxrwxrwx");
+
+    for (int i = 0; i < 9; i++) {
+      int mask = 1 << i;
+      char currentChar = ((permissions & mask) != 0) ? permissionStringBuilder.charAt(8 - i) : '-';
+      permissionStringBuilder.setCharAt(8 - i, currentChar);
+    }
+
+    return permissionStringBuilder.toString();
+  }
+
   private void unpack(Path file, Path targetDir, Function<InputStream, ArchiveInputStream> unpacker) {
 
     this.context.trace("Unpacking archive {} to {}", file, targetDir);
     try (InputStream is = Files.newInputStream(file); ArchiveInputStream ais = unpacker.apply(is)) {
       ArchiveEntry entry = ais.getNextEntry();
+      boolean isTar = ais instanceof TarArchiveInputStream;
+      boolean isZip = ais instanceof ZipArchiveInputStream;
       while (entry != null) {
+        String permissionStr = null;
+        if (isZip) {
+          // TODO ZipArchiveInputStream is unable to fill this field, you must use ZipFile if you want to read entries
+          // using this attribute (getExternalAttributes).
+          int unixMode = ((int) ((ZipArchiveEntry) entry).getExternalAttributes() >> 16) & 0xFFFF;
+          // unixMode always zero since ZipArchiveInputStream does not read getExternalAttributes()
+          System.out.println("File: " + ((ZipArchiveEntry) entry).getName());
+          System.out.println("Unix Mode: " + unixMode);
+          System.out.println("Unix Mode octal: " + Integer.toOctalString(unixMode));
+        } else if (isTar) {
+          int tarMode = ((TarArchiveEntry) entry).getMode();
+          permissionStr = generatePermissionString(tarMode);
+        }
+
         Path entryName = Paths.get(entry.getName());
         Path entryPath = targetDir.resolve(entryName).toAbsolutePath();
         if (!entryPath.startsWith(targetDir)) {
@@ -513,6 +549,8 @@ private void unpack(Path file, Path targetDir, Function<InputStream, ArchiveInpu
           mkdirs(entryPath.getParent());
           Files.copy(ais, entryPath);
         }
+        Set<PosixFilePermission> permissions = PosixFilePermissions.fromString(permissionStr);
+        Files.setPosixFilePermissions(entryPath, permissions);
         entry = ais.getNextEntry();
       }
     } catch (IOException e) {

cli/src/test/java/com/devonfw/tools/ide/io/FileAccessImplTest.java

@@ -7,6 +7,10 @@
 import java.nio.file.LinkOption;
 import java.nio.file.NoSuchFileException;
 import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.attribute.PosixFilePermission;
+import java.nio.file.attribute.PosixFilePermissions;
+import java.util.Set;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
@@ -325,7 +329,7 @@ private void createSymlinks(FileAccess fa, Path dir, boolean relative) {
 
   /**
    * Checks if the symlinks exist. This is used by the tests of {@link FileAccessImpl#symlink(Path, Path, boolean)}.
-   * 
+   *
    * @param dir the {@link Path} to the directory where the symlinks are expected.
    */
   private void assertSymlinksExist(Path dir) {
@@ -469,4 +473,44 @@ private void assertSymlinkRead(Path link, Path trueTarget) {
           + " and readPath " + readPath, e);
     }
   }
+
+  /**
+   * Test of {@link FileAccessImpl#untar(Path, Path, TarCompression)} and checks if file permissions are preserved on
+   * Linux
+   */
+  @Test
+  public void testUntarWithFilePermissions(@TempDir Path tempDir) {
+    // TODO test:
+    // NONE -> not yet checked
+    // GZ, -> checked
+    // BZIP2 -> not yet checked
+
+    // arrange
+    IdeContext context = IdeTestContextMock.get();
+    // TODO I think these are not relevant on Windows. But what about MacOS?
+    if (!context.getSystemInfo().isLinux()) {
+      return;
+    }
+
+    // act
+    context.getFileAccess().untar(
+        Path.of("src/test/resources/com/devonfw/tools/ide/io").resolve("executable_and_non_executable.tar.gz"), tempDir,
+        TarCompression.GZ);
+
+    // assert
+    assertPosixFilePermissions(tempDir.resolve("executableFile.txt"), "rwxrwxr-x");
+    assertPosixFilePermissions(tempDir.resolve("nonExecutableFile.txt"), "rw-rw-r--");
+  }
+
+  private void assertPosixFilePermissions(Path file, String permissions) {
+
+    try {
+      Set<PosixFilePermission> posixPermissions = Files.getPosixFilePermissions(file);
+      String permissionStr = PosixFilePermissions.toString(posixPermissions);
+      assertThat(permissions).isEqualTo(permissionStr);
+    } catch (IOException e) {
+      throw new RuntimeException(e);
+    }
+  }
+
 }