Re-land r313210 - Fix for bug 34532 - A few rough corners related to post-mortem debugging (core/minidump)

The main change is to avoid setting the process state as running when
debugging core/minidumps (details in the bug).  Also included a few small,
related fixes around how the errors propagate in this case.

Fixed the FreeBSD/Windows break: the intention was to keep
Process::WillResume() and Process::DoResume() "in-sync", but this had the
unfortunate consequence of breaking Process sub-classes which don't override
WillResume().

The safer approach is to keep Process::WillResume() untouched and only
override it in the minidump and core implementations.

patch by lemo

Bug: https://bugs.llvm.org/show_bug.cgi?id=34532

Differential Revision: https://reviews.llvm.org/D37651

llvm-svn: 313655
This commit is contained in:
Adrian McCarthy
2017-09-19 18:07:33 +00:00
parent 6567ecd741
commit 3887ba8d38
6 changed files with 100 additions and 5 deletions

View File

@@ -244,6 +244,34 @@ class LinuxCoreTestCase(TestBase):
end_region.GetRegionBase())
self.assertEqual(end_region.GetRegionEnd(), lldb.LLDB_INVALID_ADDRESS)
def check_state(self, process):
with open(os.devnull) as devnul:
# sanitize test output
self.dbg.SetOutputFileHandle(devnul, False)
self.dbg.SetErrorFileHandle(devnul, False)
self.assertTrue(process.is_stopped)
# Process.Continue
error = process.Continue()
self.assertFalse(error.Success())
self.assertTrue(process.is_stopped)
# Thread.StepOut
thread = process.GetSelectedThread()
thread.StepOut()
self.assertTrue(process.is_stopped)
# command line
self.dbg.HandleCommand('s')
self.assertTrue(process.is_stopped)
self.dbg.HandleCommand('c')
self.assertTrue(process.is_stopped)
# restore file handles
self.dbg.SetOutputFileHandle(None, False)
self.dbg.SetErrorFileHandle(None, False)
def do_test(self, filename, pid, region_count):
target = self.dbg.CreateTarget(filename + ".out")
process = target.LoadCore(filename + ".core")
@@ -251,6 +279,8 @@ class LinuxCoreTestCase(TestBase):
self.assertEqual(process.GetNumThreads(), 1)
self.assertEqual(process.GetProcessID(), pid)
self.check_state(process)
thread = process.GetSelectedThread()
self.assertTrue(thread)
self.assertEqual(thread.GetThreadID(), pid)

View File

@@ -31,6 +31,34 @@ class MiniDumpNewTestCase(TestBase):
lldb.DBG.SetSelectedPlatform(self._initial_platform)
super(MiniDumpNewTestCase, self).tearDown()
def check_state(self):
with open(os.devnull) as devnul:
# sanitize test output
self.dbg.SetOutputFileHandle(devnul, False)
self.dbg.SetErrorFileHandle(devnul, False)
self.assertTrue(self.process.is_stopped)
# Process.Continue
error = self.process.Continue()
self.assertFalse(error.Success())
self.assertTrue(self.process.is_stopped)
# Thread.StepOut
thread = self.process.GetSelectedThread()
thread.StepOut()
self.assertTrue(self.process.is_stopped)
# command line
self.dbg.HandleCommand('s')
self.assertTrue(self.process.is_stopped)
self.dbg.HandleCommand('c')
self.assertTrue(self.process.is_stopped)
# restore file handles
self.dbg.SetOutputFileHandle(None, False)
self.dbg.SetErrorFileHandle(None, False)
def test_process_info_in_minidump(self):
"""Test that lldb can read the process information from the Minidump."""
# target create -c linux-x86_64.dmp
@@ -40,6 +68,7 @@ class MiniDumpNewTestCase(TestBase):
self.assertTrue(self.process, PROCESS_IS_VALID)
self.assertEqual(self.process.GetNumThreads(), 1)
self.assertEqual(self.process.GetProcessID(), self._linux_x86_64_pid)
self.check_state()
def test_thread_info_in_minidump(self):
"""Test that lldb can read the thread information from the Minidump."""
@@ -47,6 +76,7 @@ class MiniDumpNewTestCase(TestBase):
self.dbg.CreateTarget(None)
self.target = self.dbg.GetSelectedTarget()
self.process = self.target.LoadCore("linux-x86_64.dmp")
self.check_state()
# This process crashed due to a segmentation fault in its
# one and only thread.
self.assertEqual(self.process.GetNumThreads(), 1)
@@ -61,6 +91,7 @@ class MiniDumpNewTestCase(TestBase):
self.dbg.CreateTarget("linux-x86_64")
self.target = self.dbg.GetSelectedTarget()
self.process = self.target.LoadCore("linux-x86_64.dmp")
self.check_state()
self.assertEqual(self.process.GetNumThreads(), 1)
self.assertEqual(self.process.GetProcessID(), self._linux_x86_64_pid)
thread = self.process.GetThreadAtIndex(0)
@@ -81,6 +112,7 @@ class MiniDumpNewTestCase(TestBase):
self.dbg.CreateTarget(None)
self.target = self.dbg.GetSelectedTarget()
self.process = self.target.LoadCore("linux-x86_64_not_crashed.dmp")
self.check_state()
self.assertEqual(self.process.GetNumThreads(), 1)
thread = self.process.GetThreadAtIndex(0)
self.assertEqual(thread.GetStopReason(), lldb.eStopReasonNone)
@@ -161,9 +193,10 @@ class MiniDumpNewTestCase(TestBase):
"""Test that we can examine local variables in a Minidump."""
# Launch with the Minidump, and inspect a local variable.
# target create linux-x86_64_not_crashed -c linux-x86_64_not_crashed.dmp
target = self.dbg.CreateTarget("linux-x86_64_not_crashed")
process = target.LoadCore("linux-x86_64_not_crashed.dmp")
thread = process.GetThreadAtIndex(0)
self.target = self.dbg.CreateTarget("linux-x86_64_not_crashed")
self.process = self.target.LoadCore("linux-x86_64_not_crashed.dmp")
self.check_state()
thread = self.process.GetThreadAtIndex(0)
frame = thread.GetFrameAtIndex(1)
value = frame.EvaluateExpression('x')
self.assertEqual(value.GetValueAsSigned(), 3)

View File

@@ -94,7 +94,7 @@ public:
bool all_threads = false;
if (command.GetArgumentCount() == 0) {
Thread *thread = m_exe_ctx.GetThreadPtr();
if (!HandleOneThread(thread->GetID(), result))
if (!thread || !HandleOneThread(thread->GetID(), result))
return false;
return result.Succeeded();
} else if (command.GetArgumentCount() == 1) {
@@ -775,6 +775,12 @@ protected:
else
error = process->Resume();
if (!error.Success()) {
result.AppendMessage(error.AsCString());
result.SetStatus(eReturnStatusFailed);
return false;
}
// There is a race condition where this thread will return up the call
// stack to the main command handler
// and show an (lldb) prompt before HandlePrivateEvent (from

View File

@@ -84,11 +84,21 @@ public:
void RefreshStateAfterStop() override;
lldb_private::Status WillResume() override {
lldb_private::Status error;
error.SetErrorStringWithFormat(
"error: %s does not support resuming processes",
GetPluginName().GetCString());
return error;
}
//------------------------------------------------------------------
// Process Queries
//------------------------------------------------------------------
bool IsAlive() override;
bool WarnBeforeDetach() const override { return false; }
//------------------------------------------------------------------
// Process Memory
//------------------------------------------------------------------

View File

@@ -82,6 +82,14 @@ public:
bool GetProcessInfo(ProcessInstanceInfo &info) override;
Status WillResume() override {
Status error;
error.SetErrorStringWithFormat(
"error: %s does not support resuming processes",
GetPluginName().GetCString());
return error;
}
MinidumpParser m_minidump_parser;
protected:

View File

@@ -1621,7 +1621,12 @@ Status Process::Resume() {
log->Printf("Process::Resume: -- TrySetRunning failed, not resuming.");
return error;
}
return PrivateResume();
Status error = PrivateResume();
if (!error.Success()) {
// Undo running state change
m_public_run_lock.SetStopped();
}
return error;
}
Status Process::ResumeSynchronous(Stream *stream) {
@@ -1650,6 +1655,9 @@ Status Process::ResumeSynchronous(Stream *stream) {
error.SetErrorStringWithFormat(
"process not in stopped state after synchronous resume: %s",
StateAsCString(state));
} else {
// Undo running state change
m_public_run_lock.SetStopped();
}
// Undo the hijacking of process events...