src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.hotspot/src/org/graalvm/compiler/hotspot/HotSpotTTYStreamProvider.java

rev 56282 : [mq]: graal

@@ -51,11 +51,12 @@
 
     public static class Options {
 
         // @formatter:off
         @Option(help = "File to which logging is sent.  A %p in the name will be replaced with a string identifying " +
-                       "the process, usually the process id and %t will be replaced by System.currentTimeMillis().", type = OptionType.Expert)
+                       "the process, usually the process id and %t will be replaced by System.currentTimeMillis().  " +
+                       "Using %o as filename sends logging to System.out whereas %e sends logging to System.err.", type = OptionType.Expert)
         public static final LogStreamOptionKey LogFile = new LogStreamOptionKey();
         // @formatter:on
     }
 
     @Override

@@ -75,20 +76,28 @@
         }
 
         /**
          * @return {@code nameTemplate} with all instances of %p replaced by
          *         {@link GraalServices#getExecutionID()} and %t by
-         *         {@link System#currentTimeMillis()}
+         *         {@link System#currentTimeMillis()}. Checks %o and %e are not combined with any
+         *         other characters.
          */
         private static String makeFilename(String nameTemplate) {
             String name = nameTemplate;
             if (name.contains("%p")) {
                 name = name.replaceAll("%p", GraalServices.getExecutionID());
             }
             if (name.contains("%t")) {
                 name = name.replaceAll("%t", String.valueOf(System.currentTimeMillis()));
             }
+
+            for (String subst : new String[]{"%o", "%e"}) {
+                if (name.contains(subst) && !name.equals(subst)) {
+                    throw new IllegalArgumentException("LogFile substitution " + subst + " cannot be combined with any other characters");
+                }
+            }
+
             return name;
         }
 
         /**
          * An output stream that redirects to {@link HotSpotJVMCIRuntime#getLogStream()}. The

@@ -104,24 +113,34 @@
                     synchronized (this) {
                         if (lazy == null) {
                             String nameTemplate = LogStreamOptionKey.this.getValue(defaultOptions());
                             if (nameTemplate != null) {
                                 String name = makeFilename(nameTemplate);
+                                switch (name) {
+                                    case "%o":
+                                        lazy = System.out;
+                                        break;
+                                    case "%e":
+                                        lazy = System.err;
+                                        break;
+                                    default:
                                 try {
                                     final boolean enableAutoflush = true;
                                     FileOutputStream result = new FileOutputStream(name);
                                     if (!Services.IS_IN_NATIVE_IMAGE) {
                                         printVMConfig(enableAutoflush, result);
                                     } else {
-                                        // There are no VM arguments for the libgraal library.
+                                                // There are no VM arguments for the libgraal
+                                                // library.
                                     }
                                     lazy = result;
-                                    return lazy;
                                 } catch (FileNotFoundException e) {
                                     throw new RuntimeException("couldn't open file: " + name, e);
                                 }
                             }
+                                return lazy;
+                            }
 
                             lazy = HotSpotJVMCIRuntime.runtime().getLogStream();
                             PrintStream ps = new PrintStream(lazy);
                             ps.printf("[Use -D%sLogFile=<path> to redirect Graal log output to a file.]%n", GRAAL_OPTION_PROPERTY_PREFIX);
                             ps.flush();