Fix filename sanitization on Windows

compiler/src/jdk.graal.compiler.test/src/jdk/graal/compiler/debug/test/StandardPathUtilitiesProviderTest.java

@@ -0,0 +1,55 @@
+/*
+ * 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.  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.
+ */
+
+package jdk.graal.compiler.debug.test;
+
+import org.junit.Assert;
+import org.junit.Assume;
+import org.junit.Test;
+
+import jdk.graal.compiler.debug.StandardPathUtilitiesProvider;
+
+public class StandardPathUtilitiesProviderTest {
+
+    @Test
+    public void sanitizesPathName() {
+        StandardPathUtilitiesProvider sut = new StandardPathUtilitiesProvider();
+        String sanitized = sut.sanitizeFileName("\0null");
+        Assert.assertEquals("_null", sanitized);
+
+        sanitized = sut.sanitizeFileName("path/with/slashes");
+        Assert.assertEquals("path_with_slashes", sanitized);
+    }
+
+    @Test
+    public void sanitizesPathNameOnWindows() {
+        Assume.assumeTrue(System.getProperty("os.name", "").startsWith("Windows"));
+
+        // Windows is pickier regarding path names
+        StandardPathUtilitiesProvider sut = new StandardPathUtilitiesProvider();
+        String sanitized = sut.sanitizeFileName("<lessthan>greaterthan:colon|bar*asterisk?question");
+        Assert.assertEquals("_lessthan_greaterthan_colon_bar_asterisk_question", sanitized);
+    }
+}

compiler/src/jdk.graal.compiler/src/jdk/graal/compiler/debug/StandardPathUtilitiesProvider.java

@@ -129,7 +129,18 @@ public String sanitizeFileName(String name) {
             }
             buf.append('_');
         }
-        return buf.toString();
+
+        /*
+         * On Windows, the original path might contain "/" as well (both "\" and "/" are equally
+         * valid path separators on Windows). Since File.separatorChar only reports "\" on Windows,
+         * we might have missed it during the previous sanitization. Paths.get should work now
+         * because we have removed all illegal characters and on Windows it canonicalizes the path
+         * to contain only "\". We thus replace any "/" that were converted to "\" here.
+         */
+        String pathString = buf.toString();
+        String sanitizedPathString = Paths.get(pathString).toString();
+        sanitizedPathString = sanitizedPathString.replace(File.separatorChar, '_');
+        return sanitizedPathString;
     }
 
     @Override