8341666: FileInputStream doesn't support readAllBytes() or readNBytes(int) on pseudo devices

Reviewed-by: alanb

src/java.base/share/classes/java/io/FileInputStream.java

@@ -29,6 +29,7 @@ import java.nio.channels.FileChannel;
 import java.util.Arrays;
 import jdk.internal.util.ArraysSupport;
 import jdk.internal.event.FileReadEvent;
+import jdk.internal.vm.annotation.Stable;
 import sun.nio.ch.FileChannelImpl;
 
 /**
@@ -81,6 +82,10 @@ public class FileInputStream extends InputStream
 
     private volatile boolean closed;
 
+    // This field indicates whether the file is a regular file as some
+    // operations need the current position which requires seeking
+    private @Stable Boolean isRegularFile;
+
     /**
      * Creates a {@code FileInputStream} to read from an existing file
      * named by the path name {@code name}.
@@ -331,6 +336,9 @@ public class FileInputStream extends InputStream
 
     @Override
     public byte[] readAllBytes() throws IOException {
+        if (!isRegularFile())
+            return super.readAllBytes();
+
         long length = length();
         long position = position();
         long size = length - position;
@@ -382,6 +390,9 @@ public class FileInputStream extends InputStream
         if (len == 0)
             return new byte[0];
 
+        if (!isRegularFile())
+            return super.readNBytes(len);
+
         long length = length();
         long position = position();
         long size = length - position;
@@ -418,7 +429,7 @@ public class FileInputStream extends InputStream
     @Override
     public long transferTo(OutputStream out) throws IOException {
         long transferred = 0L;
-        if (out instanceof FileOutputStream fos) {
+        if (out instanceof FileOutputStream fos && isRegularFile()) {
             FileChannel fc = getChannel();
             long pos = fc.position();
             transferred = fc.transferTo(pos, Long.MAX_VALUE, fos.getChannel());
@@ -471,7 +482,10 @@ public class FileInputStream extends InputStream
      */
     @Override
     public long skip(long n) throws IOException {
-        return skip0(n);
+        if (isRegularFile())
+            return skip0(n);
+
+        return super.skip(n);
     }
 
     private native long skip0(long n) throws IOException;
@@ -603,6 +617,18 @@ public class FileInputStream extends InputStream
         return fc;
     }
 
+    /**
+     * Determine whether the file is a regular file.
+     */
+    private boolean isRegularFile() {
+        Boolean isRegularFile = this.isRegularFile;
+        if (isRegularFile == null) {
+            this.isRegularFile = isRegularFile = isRegularFile0(fd);
+        }
+        return isRegularFile;
+    }
+    private native boolean isRegularFile0(FileDescriptor fd);
+
     private static native void initIDs();
 
     static {

src/java.base/share/native/libjava/FileInputStream.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -141,3 +141,9 @@ Java_java_io_FileInputStream_available0(JNIEnv *env, jobject this) {
     JNU_ThrowIOExceptionWithLastError(env, NULL);
     return 0;
 }
+
+JNIEXPORT jboolean JNICALL
+Java_java_io_FileInputStream_isRegularFile0(JNIEnv *env, jobject this, jobject fdo) {
+    FD fd = getFD(env, this, fis_fd);
+    return IO_IsRegularFile(env, fd);
+}

src/java.base/unix/native/libjava/io_util_md.c

@@ -264,3 +264,13 @@ handleGetLength(FD fd)
 #endif
     return sb.st_size;
 }
+
+jboolean
+handleIsRegularFile(JNIEnv* env, FD fd)
+{
+    struct stat fbuf;
+    if (fstat(fd, &fbuf) == -1)
+        JNU_ThrowIOExceptionWithLastError(env, "fstat failed");
+
+    return S_ISREG(fbuf.st_mode) ? JNI_TRUE : JNI_FALSE;
+}

src/java.base/unix/native/libjava/io_util_md.h

@@ -41,6 +41,7 @@ jint handleAvailable(FD fd, jlong *pbytes);
 jint handleSetLength(FD fd, jlong length);
 jlong handleGetLength(FD fd);
 FD handleOpen(const char *path, int oflag, int mode);
+jboolean handleIsRegularFile(JNIEnv* env, FD fd);
 
 /*
  * Functions to get fd from the java.io.FileDescriptor field
@@ -66,6 +67,7 @@ FD getFD(JNIEnv *env, jobject cur, jfieldID fid);
 #define IO_Available handleAvailable
 #define IO_SetLength handleSetLength
 #define IO_GetLength handleGetLength
+#define IO_IsRegularFile handleIsRegularFile
 
 /*
  * On Solaris, the handle field is unused

src/java.base/windows/native/libjava/io_util_md.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -595,3 +595,9 @@ handleGetLength(FD fd) {
         return -1;
     }
 }
+
+jboolean
+handleIsRegularFile(JNIEnv* env, FD fd)
+{
+    return JNI_TRUE;
+}

src/java.base/windows/native/libjava/io_util_md.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -51,6 +51,7 @@ jint handleAppend(FD fd, const void *buf, jint len);
 void fileDescriptorClose(JNIEnv *env, jobject this);
 JNIEXPORT jlong JNICALL
 handleLseek(FD fd, jlong offset, jint whence);
+jboolean handleIsRegularFile(JNIEnv* env, FD fd);
 
 /*
  * Returns an opaque handle to file named by "path".  If an error occurs,
@@ -82,6 +83,7 @@ FD getFD(JNIEnv *env, jobject cur, jfieldID fid);
 #define IO_Available handleAvailable
 #define IO_SetLength handleSetLength
 #define IO_GetLength handleGetLength
+#define IO_IsRegularFile handleIsRegularFile
 
 /*
  * Setting the handle field in Java_java_io_FileDescriptor_set for

test/jdk/java/io/FileInputStream/PseudoDevice.java

@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/* @test
+ * @bug 8341666
+ * @summary Test of FileInputStream reading from stdin and a named pipe
+ * @requires os.family != "windows"
+ * @library .. /test/lib
+ * @build jdk.test.lib.Platform
+ * @run junit/othervm --enable-native-access=ALL-UNNAMED PseudoDevice
+ */
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.InputStream;
+import java.io.IOException;
+import java.lang.foreign.Arena;
+import java.lang.foreign.FunctionDescriptor;
+import java.lang.foreign.Linker;
+import java.lang.foreign.MemorySegment;
+import java.lang.foreign.SymbolLookup;
+import java.lang.foreign.ValueLayout;
+import java.lang.invoke.MethodHandle;
+import jdk.test.lib.Platform;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.DisabledOnOs;
+import org.junit.jupiter.api.condition.OS;
+import static org.junit.jupiter.api.Assertions.*;
+
+public class PseudoDevice {
+
+    private static final String PIPE = "pipe";
+    private static final File PIPE_FILE = new File(PIPE);
+    private static final String SENTENCE =
+        "Rien n'est permis mais tout est possible";
+
+    private static class mkfifo {
+        public static final FunctionDescriptor DESC = FunctionDescriptor.of(
+            ValueLayout.JAVA_INT,
+            ValueLayout.ADDRESS,
+            ValueLayout.JAVA_SHORT
+        );
+
+        public static final MemorySegment ADDR;
+        static {
+            Linker linker = Linker.nativeLinker();
+            SymbolLookup stdlib = linker.defaultLookup();
+            ADDR = stdlib.find("mkfifo").orElseThrow();
+        }
+
+        public static final MethodHandle HANDLE =
+            Linker.nativeLinker().downcallHandle(ADDR, DESC);
+    }
+
+    public static int mkfifo(MemorySegment x0, short x1) {
+        var mh$ = mkfifo.HANDLE;
+        try {
+            return (int)mh$.invokeExact(x0, x1);
+        } catch (Throwable ex$) {
+           throw new AssertionError("should not reach here", ex$);
+        }
+    }
+
+    private static Thread createWriteThread() {
+        Thread t = new Thread(
+            new Runnable() {
+                public void run() {
+                    try (FileOutputStream fos = new FileOutputStream(PIPE);) {
+                        fos.write(SENTENCE.getBytes());
+                    } catch (IOException e) {
+                        throw new RuntimeException(e);
+                    }
+                }
+            }
+        );
+        t.start();
+        return t;
+    }
+
+    @BeforeAll
+    static void before() throws InterruptedException, IOException {
+        if (Platform.isWindows())
+            return;
+
+        PIPE_FILE.delete();
+        try (var newArena = Arena.ofConfined()) {
+            var addr = newArena.allocateFrom(PIPE);
+            short mode = 0666;
+            assertEquals(0, mkfifo(addr, mode));
+        }
+        if (!PIPE_FILE.exists())
+            throw new RuntimeException("Failed to create " + PIPE);
+    }
+
+    @AfterAll
+    static void after() throws IOException {
+        if (Platform.isWindows())
+            return;
+
+        PIPE_FILE.delete();
+    }
+
+    /**
+     * Tests that new FileInputStream(File).available() does not throw
+     */
+    @Test
+    @DisabledOnOs(OS.WINDOWS)
+    void availableStdin() throws IOException {
+        File stdin = new File("/dev", "stdin");
+        if (stdin.exists()) {
+            try (InputStream s = new FileInputStream(stdin);) {
+                s.available();
+            }
+        }
+    }
+
+    /**
+     * Tests that new FileInputStream(File).skip(0) does not throw
+     */
+    @Test
+    @DisabledOnOs(OS.WINDOWS)
+    void skipStdin() throws IOException {
+        File stdin = new File("/dev", "stdin");
+        if (stdin.exists()) {
+            try (InputStream s = new FileInputStream(stdin);) {
+                s.skip(0);
+            }
+        }
+    }
+
+    /**
+     * Tests new FileInputStream(File).readAllBytes().
+     */
+    @Test
+    @DisabledOnOs(OS.WINDOWS)
+    void readAllBytes() throws InterruptedException, IOException {
+        Thread t = createWriteThread();
+        try (InputStream in = new FileInputStream(PIPE)) {
+            String s = new String(in.readAllBytes());
+            System.out.println(s);
+            assertEquals(SENTENCE, s);
+        } finally {
+            t.join();
+        }
+    }
+
+    /**
+     * Tests new FileInputStream(File).readNBytes(byte[],int,int).
+     */
+    @Test
+    @DisabledOnOs(OS.WINDOWS)
+    void readNBytesNoOverride() throws InterruptedException, IOException {
+        Thread t = createWriteThread();
+        try (InputStream in = new FileInputStream(PIPE)) {
+            final int offset = 11;
+            final int length = 17;
+            assert length <= SENTENCE.length();
+            byte[] b = new byte[offset + length];
+            int n = in.readNBytes(b, offset, length);
+            String s = new String(b, offset, length);
+            System.out.println(s);
+            assertEquals(SENTENCE.substring(0, length), s);
+        } finally {
+            t.join();
+        }
+    }
+
+    /**
+     * Tests new FileInputStream(File).readNBytes(int).
+     */
+    @Test
+    @DisabledOnOs(OS.WINDOWS)
+    void readNBytesOverride() throws InterruptedException, IOException {
+        Thread t = createWriteThread();
+        try (InputStream in = new FileInputStream(PIPE)) {
+            final int length = 17;
+            assert length <= SENTENCE.length();
+            byte[] b = in.readNBytes(length);
+            String s = new String(b);
+            System.out.println(s);
+            assertEquals(SENTENCE.substring(0, length), s);
+        } finally {
+            t.join();
+        }
+    }
+}