8293121: (fs) Refactor UnixFileSystem copying into generic Unix, Linux, and BSD implementations

Reviewed-by: alanb

src/java.base/macosx/classes/sun/nio/fs/BsdFileSystem.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2022, 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
@@ -25,10 +25,14 @@
 
 package sun.nio.fs;
 
-import java.nio.file.*;
 import java.io.IOException;
-import java.util.*;
+import java.nio.file.FileStore;
+import java.nio.file.WatchService;
 import java.security.AccessController;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Set;
 import sun.security.action.GetPropertyAction;
 
 /**
@@ -104,4 +108,19 @@ class BsdFileSystem extends UnixFileSystem {
     FileStore getFileStore(UnixMountEntry entry) throws IOException {
         return new BsdFileStore(this, entry);
     }
+
+    // --- file copying ---
+
+    @Override
+    int directCopy(int dst, int src, long addressToPollForCancel)
+        throws UnixException
+    {
+        return directCopy0(dst, src, addressToPollForCancel);
+    }
+
+    // -- native methods --
+
+    private static native int directCopy0(int dst, int src,
+                                          long addressToPollForCancel)
+        throws UnixException;
 }

src/java.base/macosx/native/libnio/fs/BsdFileSystem.c

@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2022, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+
+#include "jni.h"
+#include "jni_util.h"
+#include "jlong.h"
+
+#include "nio.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include <copyfile.h>
+#include "sun_nio_fs_BsdFileSystem.h"
+
+#define RESTARTABLE(_cmd, _result) do { \
+  do { \
+    _result = _cmd; \
+  } while((_result == -1) && (errno == EINTR)); \
+} while(0)
+
+static void throwUnixException(JNIEnv* env, int errnum) {
+    jobject x = JNU_NewObjectByName(env, "sun/nio/fs/UnixException",
+        "(I)V", errnum);
+    if (x != NULL) {
+        (*env)->Throw(env, x);
+    }
+}
+
+int fcopyfile_callback(int what, int stage, copyfile_state_t state,
+    const char* src, const char* dst, void* cancel)
+{
+    if (what == COPYFILE_COPY_DATA) {
+        if (stage == COPYFILE_ERR
+                || (stage == COPYFILE_PROGRESS && *((int*)cancel) != 0)) {
+            // errno will be set to ECANCELED if the operation is cancelled,
+            // or to the appropriate error number if there is an error,
+            // but in either case we need to quit.
+            return COPYFILE_QUIT;
+        }
+    }
+    return COPYFILE_CONTINUE;
+}
+
+// Copy all bytes from src to dst, within the kernel if possible (Linux),
+// and return zero, otherwise return the appropriate status code.
+//
+// Return value
+//   0 on success
+//   IOS_UNAVAILABLE if the platform function would block
+//   IOS_UNSUPPORTED_CASE if the call does not work with the given parameters
+//   IOS_UNSUPPORTED if direct copying is not supported on this platform
+//   IOS_THROWN if a Java exception is thrown
+//
+JNIEXPORT jint JNICALL
+Java_sun_nio_fs_BsdFileSystem_directCopy0
+    (JNIEnv* env, jclass this, jint dst, jint src, jlong cancelAddress)
+{
+    volatile jint* cancel = (jint*)jlong_to_ptr(cancelAddress);
+
+    copyfile_state_t state;
+    if (cancel != NULL) {
+        state = copyfile_state_alloc();
+        copyfile_state_set(state, COPYFILE_STATE_STATUS_CB, fcopyfile_callback);
+        copyfile_state_set(state, COPYFILE_STATE_STATUS_CTX, (void*)cancel);
+    } else {
+        state = NULL;
+    }
+    if (fcopyfile(src, dst, state, COPYFILE_DATA) < 0) {
+        int errno_fcopyfile = errno;
+        if (state != NULL)
+            copyfile_state_free(state);
+        throwUnixException(env, errno_fcopyfile);
+        return IOS_THROWN;
+    }
+    if (state != NULL)
+        copyfile_state_free(state);
+
+    return 0;
+}