commit a35970a6f67369691d3fd96eb47a3cff5d7ef0a4
author Daniel Malea <daniel.malea@intel.com> Fri Nov 23 18:09:58 2012 +0000
committer Daniel Malea <daniel.malea@intel.com> Fri Nov 23 18:09:58 2012 +0000
tree 52154a4e7df8fdb97d6b6c0fb3599265b52df334
parent b3b60570e31e2e4191d6cb310dd9330651c40dce

Fix Linux bug that leaves lldb in invalid state after expression evaluation times out.
- Handle EINVAL return code from ptrace(GETSIGINFO, ...): not an error, but 'group-stop' state on Linux
- propagate SIGSTOP to inferior in above case
- this commit resolves the failure in expression_command/timeout testcase

Thanks to Sean Callanan & Matt Kopec for helping debug this problem

llvm-svn: 168523

lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp

diff --git a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
index ac8a0b9..177153a 100644
--- a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
+++ b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
@@ -502,8 +502,8 @@
 class SiginfoOperation : public Operation
 {
 public:
-    SiginfoOperation(lldb::tid_t tid, void *info, bool &result)
-        : m_tid(tid), m_info(info), m_result(result) { }
+    SiginfoOperation(lldb::tid_t tid, void *info, bool &result, int &ptrace_err)
+        : m_tid(tid), m_info(info), m_result(result), m_err(ptrace_err) { }
 
     void Execute(ProcessMonitor *monitor);
 
@@ -511,6 +511,7 @@
     lldb::tid_t m_tid;
     void *m_info;
     bool &m_result;
+    int &m_err;
 };
 
 void
@@ -518,9 +519,10 @@
 {
     struct ptrace_lwpinfo plwp;
 
-    if (PTRACE(PT_LWPINFO, m_tid, (caddr_t)&plwp, sizeof(plwp)))
+    if (PTRACE(PT_LWPINFO, m_tid, (caddr_t)&plwp, sizeof(plwp))) {
         m_result = false;
-    else {
+        m_err = errno;
+    } else {
         memcpy(m_info, &plwp.pl_siginfo, sizeof(siginfo_t));
         m_result = true;
     }
@@ -1060,8 +1062,9 @@
     ProcessFreeBSD *process = monitor->m_process;
     bool stop_monitoring;
     siginfo_t info;
+    int ptrace_err;
 
-    if (!monitor->GetSignalInfo(pid, &info))
+    if (!monitor->GetSignalInfo(pid, &info, ptrace_err))
         stop_monitoring = true; // pid is gone.  Bail.
     else {
         switch (info.si_signo)
@@ -1488,10 +1491,10 @@
 }
 
 bool
-ProcessMonitor::GetSignalInfo(lldb::tid_t tid, void *siginfo)
+ProcessMonitor::GetSignalInfo(lldb::tid_t tid, void *siginfo, int &ptrace_err)
 {
     bool result;
-    SiginfoOperation op(tid, siginfo, result);
+    SiginfoOperation op(tid, siginfo, result, ptrace_err);
     DoOperation(&op);
     return result;
 }

lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h

diff --git a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h
index 9c63004..5530ca3 100644
--- a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h
+++ b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h
@@ -132,7 +132,7 @@
     /// Writes a siginfo_t structure corresponding to the given thread ID to the
     /// memory region pointed to by @p siginfo.
     bool
-    GetSignalInfo(lldb::tid_t tid, void *siginfo);
+    GetSignalInfo(lldb::tid_t tid, void *siginfo, int &errno);
 
     /// Writes the raw event message code (vis-a-vis PTRACE_GETEVENTMSG)
     /// corresponding to the given thread IDto the memory pointed to by @p