From 217f31a899c58a2529718e9dca253a241c6cfcbc Mon Sep 17 00:00:00 2001
From: Tobias Crawley <tcrawley@gmail.com>
Date: Thu, 21 Jul 2011 10:12:13 -0400
Subject: [PATCH] Allow disabling ENV write-through to the real environment
 [JRUBY-5934]

This adds updateNativeENVEnabled to RubyInstanceConfig with a default of true.
If it is true and jruby.native.enabled is also true, any modifications to
the runtime's ruby ENV will be reflected in the system env via POSIX. Otherwise,
the modifications are not written through.

This setting has not yet been pushed out to the embedding API's (ScriptingContainer
& JRubyEngine), nor has it been documented.
---
 src/org/jruby/RubyGlobal.java                 | 17 +++---
 src/org/jruby/RubyInstanceConfig.java         | 14 ++++-
 test/org/jruby/test/TestRuby.java             | 55 ++++++++++++++++++-
 .../jruby/test/TestRubyInstanceConfig.java    |  1 +
 4 files changed, 77 insertions(+), 10 deletions(-)

diff --git a/src/org/jruby/RubyGlobal.java b/src/org/jruby/RubyGlobal.java
index fcb2bd04b95..f3bc9ffba29 100644
--- a/src/org/jruby/RubyGlobal.java
+++ b/src/org/jruby/RubyGlobal.java
@@ -73,8 +73,8 @@ public class RubyGlobal {
      */
     public static class CaseInsensitiveStringOnlyRubyHash extends StringOnlyRubyHash {
         
-        public CaseInsensitiveStringOnlyRubyHash(Ruby runtime, Map valueMap, IRubyObject defaultValue) {
-            super(runtime, valueMap, defaultValue, true);
+        public CaseInsensitiveStringOnlyRubyHash(Ruby runtime, Map valueMap, IRubyObject defaultValue, boolean updateRealENV) {
+            super(runtime, valueMap, defaultValue, updateRealENV);
         }
 
         @Override
@@ -382,11 +382,14 @@ private static void defineGlobalEnvConstants(Ruby runtime) {
     		environmentVariableMap = new HashMap();
     	}
 
-        CaseInsensitiveStringOnlyRubyHash h1 = new CaseInsensitiveStringOnlyRubyHash(runtime,
-                                                       environmentVariableMap, runtime.getNil());
-        h1.getSingletonClass().defineAnnotatedMethods(CaseInsensitiveStringOnlyRubyHash.class);
-        runtime.defineGlobalConstant("ENV", h1);
-        runtime.setENV(h1);
+    	CaseInsensitiveStringOnlyRubyHash env = new CaseInsensitiveStringOnlyRubyHash(runtime,
+                                                       environmentVariableMap, 
+                                                       runtime.getNil(),
+                                                       RubyInstanceConfig.nativeEnabled && 
+                                                           runtime.getInstanceConfig().isUpdateNativeENVEnabled() );
+        env.getSingletonClass().defineAnnotatedMethods(CaseInsensitiveStringOnlyRubyHash.class);
+        runtime.defineGlobalConstant("ENV", env);
+        runtime.setENV(env);
 
         // Define System.getProperties() in ENV_JAVA
         Map systemProps = environment.getSystemPropertiesMap(runtime);
diff --git a/src/org/jruby/RubyInstanceConfig.java b/src/org/jruby/RubyInstanceConfig.java
index 0717afd5efb..9175c73da8e 100644
--- a/src/org/jruby/RubyInstanceConfig.java
+++ b/src/org/jruby/RubyInstanceConfig.java
@@ -251,7 +251,8 @@ public enum ProfilingMode {
     private String threadDumpSignal = null;
     private boolean hardExit = false;
     private boolean disableGems = false;
-
+    private boolean updateNativeENVEnabled = true;
+    
     private int safeLevel = 0;
 
     private String jrubyHome;
@@ -427,6 +428,7 @@ public RubyInstanceConfig(RubyInstanceConfig parentConfig) {
         runRubyInProcess = parentConfig.runRubyInProcess;
         excludedMethods = parentConfig.excludedMethods;
         threadDumpSignal = parentConfig.threadDumpSignal;
+        updateNativeENVEnabled = parentConfig.updateNativeENVEnabled;
         
         classCache = new ClassCache<Script>(loader, jitMax);
 
@@ -1029,6 +1031,16 @@ private String verifyHome(String home) {
         return home;
     }
 
+    
+    public boolean isUpdateNativeENVEnabled() {
+        return updateNativeENVEnabled;
+    }
+
+    public void setUpdateNativeENVEnabled(boolean updateNativeENVEnabled) {
+        this.updateNativeENVEnabled = updateNativeENVEnabled;
+    }
+
+
     private final class Argument {
         public final String originalValue;
         public final String dashedValue;
diff --git a/test/org/jruby/test/TestRuby.java b/test/org/jruby/test/TestRuby.java
index e96cc05938a..e95c184b002 100644
--- a/test/org/jruby/test/TestRuby.java
+++ b/test/org/jruby/test/TestRuby.java
@@ -35,14 +35,16 @@
 
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.Arrays;
 
 import org.jruby.Ruby;
 import org.jruby.RubyArray;
 import org.jruby.RubyException;
-import org.jruby.RubyInstanceConfig;
 import org.jruby.RubyIO;
+import org.jruby.RubyInstanceConfig;
 import org.jruby.RubyString;
 import org.jruby.exceptions.RaiseException;
 import org.jruby.runtime.Block;
@@ -55,7 +57,7 @@
  * @author Benoit
 */
 public class TestRuby extends TestRubyBase {
-
+    
     public TestRuby(String name) {
         super(name);
     }
@@ -80,6 +82,55 @@ public void testVarAndMet() throws Exception {
         assertEquals("135 20 3", eval("puts $f, \" \", $g, \" \",  $h"));
     }
     
+    public void testNativeENVSetting() throws Exception {
+        runtime = Ruby.newInstance();
+        runtime.evalScriptlet("ENV['ham'] = 'biscuit'");
+        assertEquals("biscuit", runtime.getPosix().getenv("ham"));
+    }
+    
+    public void testNativeENVSettingWhenItIsDisabledOnTheRuntime() throws Exception {
+        RubyInstanceConfig cfg = new RubyInstanceConfig();
+        cfg.setUpdateNativeENVEnabled(false);
+        runtime = Ruby.newInstance(cfg);
+        runtime.evalScriptlet("ENV['biscuit'] = 'gravy'");
+        assertNull(runtime.getPosix().getenv("biscuit"));
+    }
+    
+    public void testNativeENVSettingWhenNativeIsDisabledGlobally() throws Exception {
+        try {
+            setNativeEnabled(false);
+            runtime = Ruby.newInstance();
+            runtime.evalScriptlet("ENV['gravy'] = 'with sausage'");
+            assertNull(runtime.getPosix().getenv("gravy"));
+        } finally {
+            setNativeEnabled(true);
+        }
+    }
+    
+    public void testNativeENVSettingWhenNativeIsDisabledGloballyButExplicitlyEnabledOnTheRuntime() throws Exception {
+        try {
+            setNativeEnabled(false);
+            RubyInstanceConfig cfg = new RubyInstanceConfig();
+            cfg.setUpdateNativeENVEnabled(true);
+            runtime = Ruby.newInstance(cfg);
+            runtime.evalScriptlet("ENV['sausage'] = 'biscuits'");
+            assertNull(runtime.getPosix().getenv("sausage"));
+        } finally {
+            setNativeEnabled(true);
+        }
+    }
+    
+    private void setNativeEnabled(boolean nativeEnabled) throws Exception {
+        Field nativeEnabledField = RubyInstanceConfig.class.getDeclaredField("nativeEnabled");
+        nativeEnabledField.setAccessible(true);
+
+        Field modifiers = Field.class.getDeclaredField("modifiers");
+        modifiers.setAccessible(true);
+        modifiers.setInt(nativeEnabledField, nativeEnabledField.getModifiers() & ~Modifier.FINAL);
+        
+        nativeEnabledField.set(RubyInstanceConfig.class, nativeEnabled);
+    }
+    
     public void testPrintErrorWithNilBacktrace() throws Exception {
         testPrintErrorWithBacktrace("nil");
     }
diff --git a/test/org/jruby/test/TestRubyInstanceConfig.java b/test/org/jruby/test/TestRubyInstanceConfig.java
index 2556b9dff1d..b66e6592e4b 100644
--- a/test/org/jruby/test/TestRubyInstanceConfig.java
+++ b/test/org/jruby/test/TestRubyInstanceConfig.java
@@ -56,6 +56,7 @@ public void testRubyInstanceConfigDefaults() throws Exception {
         assertNull(config.getScriptFileName());
         assertTrue(config.loadPaths().isEmpty());
         assertTrue(config.requiredLibraries().isEmpty());
+        assertTrue(config.isUpdateNativeENVEnabled());
     }
 
     protected final static class NullLoadService extends LoadService {