[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

Re: [PATCH] Fix for a JNI bug in CreateJ.cpp (JavaHL)

From: Byeongcheol Lee <lineonking_at_gmail.com>
Date: Tue, 18 May 2010 23:21:32 -0500

[[[
* subversion/bindings/javahl/native/CreateJ.cpp
 (Set): Use CallBooleanMethod for a method returning a boolean value.
]]]

On Tue, May 18, 2010 at 10:25 PM, Hyrum K. Wright
<hyrum_wright_at_mail.utexas.edu> wrote:
>
>
> On Tue, May 18, 2010 at 10:14 PM, Byeongcheol Lee <lineonking_at_gmail.com>
> wrote:
>>
>> Dear Subversion Developers:
>>
>> I attach a patch for a JNI bug. To reproduce the bug, run your JavaHL
>> regression test under our dynamic JNI bug detector, Jinn
>> [http://userweb.cs.utexas.edu/~bclee/jinn].
>>
>> $env JAVA_TOOL_OPTIONS=-agentlib:jinn make check-javahl
>> ...
>> .Exception in thread "main" xtc.lang.blink.agent.JNIAssertionFailure:
>> The return type mismatch in CallObjectMethodV: method 0x9626fe4 has
>> return type: (Ljava/lang/Object;)Z
>>        at
>> xtc.lang.blink.agent.JNIAssertionFailure.assertFail(JNIAssertionFailure.java:16)
>>        at org.apache.subversion.javahl.SVNClient.doImport(Native Method)
>>        at org.apache.subversion.javahl.SVNTests.setUp(SVNTests.java:239)
>>        at junit.framework.TestCase.runBare(TestCase.java:128)
>>        at junit.framework.TestResult$1.protect(TestResult.java:106)
>>        at junit.framework.TestResult.runProtected(TestResult.java:124)
>>        at junit.framework.TestResult.run(TestResult.java:109)
>>        at junit.framework.TestCase.run(TestCase.java:120)
>>        at junit.framework.TestSuite.runTest(TestSuite.java:230)
>>        at junit.framework.TestSuite.run(TestSuite.java:225)
>>        at junit.framework.TestSuite.runTest(TestSuite.java:230)
>>        at junit.framework.TestSuite.run(TestSuite.java:225)
>>        at junit.textui.TestRunner.doRun(TestRunner.java:121)
>>        at junit.textui.TestRunner.doRun(TestRunner.java:114)
>>        at junit.textui.TestRunner.run(TestRunner.java:77)
>>        at org.apache.subversion.javahl.RunTests.main(RunTests.java:116)
>> ...
>>
>> To understand what caused the JNI error, I attached a gdb to the JVM.
>> Relevant caling context and source lines are here.
>>
>> #5  0x8f86cdf5 in CreateJ::Set (objects=...)
>>    at subversion/bindings/javahl/native/CreateJ.cpp:912
>> #6  0x8f86bf4f in CommitMessage::getCommitMessage (this=0x81bf6d0,
>>    commit_items=0x817ea60)
>>    at subversion/bindings/javahl/native/CommitMessage.cpp:210
>> ...
>> #11 0x8f88bff0 in Java_org_apache_subversion_javahl_SVNClient_doImport (
>>    env=0x805a518, jthis=0xb7281ce4, jpath=0xb7281ce0, jurl=0xb7281cdc,
>>    jmessage=0x0, jdepth=0xb7281cd4, jnoIgnore=0 '\000',
>>    jignoreUnknownNodeTypes=0 '\000', jrevpropTable=0x0)
>>    at
>> subversion/bindings/javahl/native/org_apache_subversion_javahl_SVNClient.cpp:792
>>
>> In subversion/bindings/javahl/native/CreateJ.cpp
>> ...
>>   883    jclass clazz = env->FindClass("java/util/HashSet");
>> ...
>>   895    static jmethodID add_mid = 0;
>> ...
>>   898        add_mid = env->GetMethodID(clazz, "add",
>> "(Ljava/lang/Object;)Z");
>> ...
>>   912        env->CallObjectMethod(set, add_mid, jthing);
>> ...
>>
>>
>> There is a JNI type mismatch between Line 898 and 912.
>>  The "add_mid" at Line 898 points a Java method returning a boolean
>> value, but the
>>  JNI function at Line 912 assumes that "add_mid" is returning a Java
>> reference.
>> This violates a JNI programming rule:
>>
>> "You should replace type in Call<type>Method with the Java type of the
>> method you are calling"
>>
>>  [http://java.sun.com/javase/6/docs/technotes/guides/jni/spec/functions.html#wp4256]
>>
>> The fix is trivial and obvious, and line 912 must change its JNI
>> function from "CallObjectMethod"
>> to "CallBooleanMethod."
>
> The patch looks sound.  Would you write a log message, per the patch
> submission guidelines[1]?  You can find our log message format at [2].
>
> Thanks!
>
> -Hyrum
>
> [1] http://subversion.apache.org/docs/community-guide/general.html#patches
> [2]
> http://subversion.apache.org/docs/community-guide/conventions.html#log-messages
>
Received on 2010-05-19 06:22:06 CEST

This is an archived mail posted to the Subversion Dev mailing list.