Commit Graph

19 Commits

Author SHA1 Message Date
Greg Clayton 7ec3d40ec0 Finally tracked down the racy condition that would hose up our debug
sessions: When continue packet has been sent and an interrupt packet was
quickly sent, it would get read at the same time:

$c#00\x03

There was an error where the packet end index was always being computed 
incorrectly by debugserver, but it wouldn't matter if there weren't extra
bytes on the end (the hex \x03 interrupt byte in this case). The first
'$' last 3 bytes of the data in the packet buffer were being trimmed
(trying to trim the '#' + checksum (#XX)) which made:

c#

And this would then be passed to the handle routine for the 'c' packet which
would see an extra character at the end and assume it was going to be in the
form c[addr] where "[addr]" was a hex address to resume at and this would
result in a malformed packet response. This is now fixed and everything works
great.

Another issue was issuing async packets correctly by doing correct handshakes
between the thread that wants to send the async packet, and the thread that
is tracking the current run.

Added a write lock to the communication class as well to make sure you never
get two threads trying to write data at the same time. This wasn't happening,
but it is a good idea to make sure it doesn't.

llvm-svn: 124369
2011-01-27 09:02:32 +00:00
Stephen Wilson a08cfb1299 Do not pass an invalid thread to Thread{Cancel,Join}.
A race condition exists between StopReadThread and the reader thread proper.
When StopReadThread sets m_read_thread_enabled to false the reader thread can
terminate and set m_read_thread to LLDB_INVALID_HOST_THREAD on exit.  Thus calls
to ThreadCancel or ThreadJoin in StopReadThread can be passed an invalid handle.

This patch removes the race by using m_read_thread_enabled as the flag thru
which the reader thread can notify the parent thread of early/abnormal
termination.

llvm-svn: 123309
2011-01-12 04:22:54 +00:00
Greg Clayton 8b2fe6dcbd Modified LLDB expressions to not have to JIT and run code just to see variable
values or persistent expression variables. Now if an expression consists of
a value that is a child of a variable, or of a persistent variable only, we
will create a value object for it and make a ValueObjectConstResult from it to
freeze the value (for program variables only, not persistent variables) and
avoid running JITed code. For everything else we still parse up and JIT code
and run it in the inferior. 

There was also a lot of clean up in the expression code. I made the 
ClangExpressionVariables be stored in collections of shared pointers instead
of in collections of objects. This will help stop a lot of copy constructors on
these large objects and also cleans up the code considerably. The persistent
clang expression variables were moved over to the Target to ensure they persist
across process executions.

Added the ability for lldb_private::Target objects to evaluate expressions.
We want to evaluate expressions at the target level in case we aren't running
yet, or we have just completed running. We still want to be able to access the
persistent expression variables between runs, and also evaluate constant 
expressions. 

Added extra logging to the dynamic loader plug-in for MacOSX. ModuleList objects
can now dump their contents with the UUID, arch and full paths being logged with
appropriate prefix values.

Thread hardened the Communication class a bit by making the connection auto_ptr
member into a shared pointer member and then making a local copy of the shared
pointer in each method that uses it to make sure another thread can't nuke the
connection object while it is being used by another thread.

Added a new file to the lldb/test/load_unload test that causes the test a.out file
to link to the libd.dylib file all the time. This will allow us to test using
the DYLD_LIBRARY_PATH environment variable after moving libd.dylib somewhere else.

llvm-svn: 121745
2010-12-14 02:59:59 +00:00
Greg Clayton bfae66ae1d Fixed a multi-threaded race condition that could happen when communication classes are shutting down. We currently don't protect communication connection classes against multi-threaded access. The connection is stored in the lldb_private::Communication.m_connection_ap auto_ptr member. We either need to add protections when accessing this class or not let anything racy occur. With this fix, we are doing the latter.
llvm-svn: 121647
2010-12-12 21:50:57 +00:00
Greg Clayton 10177aa05e Added the ability to dump sections to a certain depth (for when sections
have children sections).

Modified SectionLoadList to do it's own multi-threaded protected on its map.
The ThreadSafeSTLMap class was difficult to deal with and wasn't providing
much utility, it was only getting in the way.

Make sure when the communication read thread is about to exit, it clears the
thread in the main class.

Fixed the ModuleList to correctly ignore architectures and UUIDs if they aren't
valid when searching for a matching module. If we specified a file with no arch,
and then modified the file and loaded it again, it would not match on subsequent
searches if the arch was invalid since it would compare an invalid architecture
to the one that was found or selected within the shared library or executable.
This was causing stale modules to stay around in the global module list when they
should have been removed.

Removed deprecated functions from the DynamicLoaderMacOSXDYLD class.

Modified "ProcessGDBRemote::IsAlive" to check if we are connected to a gdb
server and also make sure our process hasn't exited.

llvm-svn: 121236
2010-12-08 05:08:21 +00:00
Greg Clayton d46c87a1a8 More reverting of the EOF stuff as the API was changed which we don't want to
do. Closing on EOF is an option that can be set on the 
lldb_private::Communication or the lldb::SBCommunication objects after they
are created. Of course the EOF support isn't hooked up, so they don't do 
anything at the moment, but they are left in so when the code is fixed, it 
will be easy to get working again.

llvm-svn: 120885
2010-12-04 02:39:47 +00:00
Greg Clayton 7788e5fd64 Reverted the close on EOF stuff again as it was crashing Xcode.
llvm-svn: 120883
2010-12-04 02:22:36 +00:00
Caroline Tice 82305fc59a Add proper EOF handling to Communication & Connection classes:
Add bool member to Communication class indicating whether the
Connection should be closed on receiving an EOF or not.  Update the
Connection read to return an EOF status when appropriate.  Modify the
Communication class to pass the EOF along or not, and to close the
Connection or not, as appropriate.

llvm-svn: 120723
2010-12-02 18:31:56 +00:00
Greg Clayton cd55b1957e Revert the End of file stuff that was added as it was causing read threads
to hang around and take a ton of CPU time. Caroline will fix this when she
gets back from vacation.

llvm-svn: 119877
2010-11-20 00:17:57 +00:00
Caroline Tice efed613172 Add the ability to catch and do the right thing with Interrupts (often control-c)
and end-of-file (often control-d).

llvm-svn: 119837
2010-11-19 20:47:54 +00:00
Greg Clayton 2d4edfbc6a Modified all logging calls to hand out shared pointers to make sure we
don't crash if we disable logging when some code already has a copy of the
logger. Prior to this fix, logs were handed out as pointers and if they were
held onto while a log got disabled, then it could cause a crash. Now all logs
are handed out as shared pointers so this problem shouldn't happen anymore.
We are also using our new shared pointers that put the shared pointer count
and the object into the same allocation for a tad better performance.

llvm-svn: 118319
2010-11-06 01:53:30 +00:00
Caroline Tice 20ad3c40f4 Add the ability to disable individual log categories, rather
than just the entire log channel.

Add checks, where appropriate, to make sure a log channel/category has 
not been disabled before attempting to write to it.

llvm-svn: 117715
2010-10-29 21:48:37 +00:00
Caroline Tice ceb6b1393d First pass at adding logging capabilities for the API functions. At the moment
it logs the function calls, their arguments and the return values.  This is not
complete or polished, but I am committing it now, at the request of someone who
really wants to use it, even though it's not really done.  It currently does not
attempt to log all the functions, just the most important ones.  I will be 
making further adjustments to the API logging code over the next few days/weeks.
(Suggestions for improvements are welcome).


Update the Python build scripts to re-build the swig C++ file whenever 
the python-extensions.swig file is modified.

Correct the help for 'log enable' command (give it the correct number & type of
arguments).

llvm-svn: 117349
2010-10-26 03:11:13 +00:00
Greg Clayton 86c3f345c6 Fixed a race condition that was sometimes stopping our command line
interpreter from working. The communication read thread could
startup and immediately exit if m_read_thread_enabled was
checked in the thread function before it was set by the
thread that spawns the read thread. Now m_read_thread_enabled is set
to true prior to spawning the read thread to avoid this issue.

Hopefully this will clear up the sporatic failures in our test suite.

llvm-svn: 113947
2010-09-15 05:19:45 +00:00
Greg Clayton 26661bca20 Remove a premature invalidation of a threads pthread_t handle, thus avoiding
a segfault when calling pthread_cancel.  Also, sets m_read_thread_enabled if
the thread is actually spawned.

Patch from Stephen Wilson.

llvm-svn: 109227
2010-07-23 15:43:25 +00:00
Greg Clayton 471b31ce62 Remove use of STL collection class use of the "data()" method since it isn't
part of C++'98. Most of these were "std::vector<T>::data()" and 
"std::string::data()".

llvm-svn: 108957
2010-07-20 22:52:08 +00:00
Eli Friedman 8878f87fb6 Misc warning fixes.
llvm-svn: 108029
2010-07-09 22:53:18 +00:00
Eli Friedman 889669769f Add missing includes.
llvm-svn: 105712
2010-06-09 08:50:27 +00:00
Chris Lattner 30fdc8d841 Initial checkin of lldb code from internal Apple repo.
llvm-svn: 105619
2010-06-08 16:52:24 +00:00