Derek (mantis #28830)
o ability for a thread to acquire a readlock when it already holds a
write lock, or vice versa
o detect when thread1 releases a lock while it hadn't acquired one
o correct result of beginwrite (return true only when another thread
held/acquired a write lock before the current thread got it)
o extra compared to Derek's patch: replaced some additional
(mostly pre-existing) interlocked*() hacks with proper memory
barriers, made formatting consistent, fixed compilation on platforms
where tthreadid is not an integer type, improved tthreadid hashing
function for 64 bit platforms, fixed some comments
git-svn-id: trunk@34678 -
critical section, so that it can be entered recursively just like
the one from TSimpleRWSync + test
- reverted r14593, since the reason for using TRWSync instead of
TMultiReadExclusiveWriteSynchronizer was because the former
supported recursive write locks
git-svn-id: trunk@14594 -