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https://issues.apache.org/jira/browse/LOGCXX-430?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15117270#comment-15117270
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Thorsten Schöning commented on LOGCXX-430:
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I removed the blocking of version 0.11.0 for now, because there are lot of
other issues open as well and this one doesn't sound terribly more bad than the
others, which don't block a release currently.
> LogManager::getRootLogger is not thread-safe
> --------------------------------------------
>
> Key: LOGCXX-430
> URL: https://issues.apache.org/jira/browse/LOGCXX-430
> Project: Log4cxx
> Issue Type: Bug
> Components: Core
> Affects Versions: 0.10.0
> Reporter: Thorsten Schöning
> Assignee: Thorsten Schöning
> Attachments: LOGCXX-430-with-mutex-1.patch,
> LOGCXX-430-with-mutex-2.patch, LOGCXX-430.patch
>
>
> Kaspar Fischer reported following on the user mailing list:
> > I am running into a situation where calling getRootLogger()
> > concurrently from many requests results in a EXC_BAD_ACCESS:
> > liblog4cxx.10.dylib`log4cxx::LogManager::getRootLogger():
> > 0x101f180a0: pushq %rbp
> > 0x101f180a1: movq %rsp, %rbp
> > 0x101f180a4: pushq %rbx
> > 0x101f180a5: pushq %rax
> > 0x101f180a6: movq %rdi, %rbx
> > 0x101f180a9: callq 0x101f17de0 ;
> > log4cxx::LogManager::getLoggerRepository()
> > 0x101f180ae: movq 8(%rax), %rsi
> > 0x101f180b2: movq (%rsi), %rax
> > 0x101f180b5: movq %rbx, %rdi
> > 0x101f180b8: callq *120(%rax) <<<<<< THREAD 1: EXC_BAD_ACCESS
> > (code=EXC_I386_GPFLT)
> > 0x101f180bb: movq %rbx, %rax
> > 0x101f180be: addq $8, %rsp
> > 0x101f180c2: popq %rbx
> > 0x101f180c3: popq %rbp
> > 0x101f180c4: ret
> > 0x101f180c5: nopw %cs:(%rax,%rax)
> > If I replace the logging statement with a statement that writes to
> > std::cerr, I do not run into any problems.
> > I am using log4cxx 0.10.0 on MacOS 10.9.1.
> The call to getRootLogger ultimately results in:
> > RepositorySelectorPtr& LogManager::getRepositorySelector() {
> > //
> > // call to initialize APR and trigger "start" of logging clock
> > //
> > APRInitializer::initialize();
> > static spi::RepositorySelectorPtr selector;
> > return selector;
> > }
> It looks like we have the same problem here like in LOGCXX-394, a function
> static which is not thread-safe. Therefore we shoudl fix this like we did in
> LOGCXX-394 by removing the function static.
> Problem is that for this to work we need to change the return type of the
> function, which shouldn't be a problem because it's private, but need to
> change additional functions as well: getLoggerRepository and
> setRepositorySelector both currently rely on the current behavior of
> getRepositorySelector.
> Additionally what I don't understand is why APRInitializer is called more
> than once even if RepositorySelector only got created once because of it's
> static.
> Looks ike we need to rework the whole part, maybe make it static on a class
> level like the guard.
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