Fix TestProcesslaunch regression caused by D7372
Summary:
After closing all the leaked file descriptors to the inferior tty, the following problem occured:
- when stdin, stdout and stderr are redirected, there are no slave descriptors open (which is good)
- lldb has a reader thread, which attempts to read from the master end of the tty
- this thread receives an EOF
- in response, it closes it's master end
- as this is the last open file descriptor for the master end, this deletes the tty and sends
SIGHUP to the inferior (this is bad)
I fix this problem by making sure the master end remains open for the duration of the inferior
process by storing a copy of the file descriptor in ProcessMonitor. I create a copy to avoid
ownership issues with the reading thread.
Reviewers: ovyalov, emaste
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D7440
llvm-svn: 228391
diff --git a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
index d78d750..b33f833 100644
--- a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
+++ b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
@@ -1587,11 +1587,10 @@
StopOpThread();
sem_destroy(&m_operation_pending);
sem_destroy(&m_operation_done);
-
- // Note: ProcessPOSIX passes the m_terminal_fd file descriptor to
- // Process::SetSTDIOFileDescriptor, which in turn transfers ownership of
- // the descriptor to a ConnectionFileDescriptor object. Consequently
- // even though still has the file descriptor, we shouldn't close it here.
+ if (m_terminal_fd >= 0) {
+ close(m_terminal_fd);
+ m_terminal_fd = -1;
+ }
}
// FIXME: On Linux, when a new thread is created, we receive to notifications,
diff --git a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h
index 6cc7d63..4ae963c 100644
--- a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h
+++ b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.h
@@ -79,7 +79,8 @@
/// Reads from this file descriptor yield both the standard output and
/// standard error of this debugee. Even if stderr and stdout were
/// redirected on launch it may still happen that data is available on this
- /// descriptor (if the inferior process opens /dev/tty, for example).
+ /// descriptor (if the inferior process opens /dev/tty, for example). This descriptor is
+ /// closed after a call to StopMonitor().
///
/// If this monitor was attached to an existing process this method returns
/// -1.
diff --git a/lldb/source/Plugins/Process/Linux/ProcessMonitor.cpp b/lldb/source/Plugins/Process/Linux/ProcessMonitor.cpp
index 81eb4d6..b2754bc 100644
--- a/lldb/source/Plugins/Process/Linux/ProcessMonitor.cpp
+++ b/lldb/source/Plugins/Process/Linux/ProcessMonitor.cpp
@@ -2345,11 +2345,10 @@
StopOpThread();
sem_destroy(&m_operation_pending);
sem_destroy(&m_operation_done);
-
- // Note: ProcessPOSIX passes the m_terminal_fd file descriptor to
- // Process::SetSTDIOFileDescriptor, which in turn transfers ownership of
- // the descriptor to a ConnectionFileDescriptor object. Consequently
- // even though still has the file descriptor, we shouldn't close it here.
+ if (m_terminal_fd >= 0) {
+ close(m_terminal_fd);
+ m_terminal_fd = -1;
+ }
}
void
diff --git a/lldb/source/Plugins/Process/Linux/ProcessMonitor.h b/lldb/source/Plugins/Process/Linux/ProcessMonitor.h
index 27beaef..0543e93 100644
--- a/lldb/source/Plugins/Process/Linux/ProcessMonitor.h
+++ b/lldb/source/Plugins/Process/Linux/ProcessMonitor.h
@@ -84,7 +84,8 @@
/// Reads from this file descriptor yield both the standard output and
/// standard error of this debugee. Even if stderr and stdout were
/// redirected on launch it may still happen that data is available on this
- /// descriptor (if the inferior process opens /dev/tty, for example).
+ /// descriptor (if the inferior process opens /dev/tty, for example). This descriptor is
+ /// closed after a call to StopMonitor().
///
/// If this monitor was attached to an existing process this method returns
/// -1.
diff --git a/lldb/source/Plugins/Process/POSIX/ProcessPOSIX.cpp b/lldb/source/Plugins/Process/POSIX/ProcessPOSIX.cpp
index 0e5ab5a..882fac7 100644
--- a/lldb/source/Plugins/Process/POSIX/ProcessPOSIX.cpp
+++ b/lldb/source/Plugins/Process/POSIX/ProcessPOSIX.cpp
@@ -252,7 +252,16 @@
if (!error.Success())
return error;
- SetSTDIOFileDescriptor(m_monitor->GetTerminalFD());
+ int terminal = m_monitor->GetTerminalFD();
+ if (terminal >= 0) {
+ // The reader thread will close the file descriptor when done, so we pass it a copy.
+ int stdio = fcntl(terminal, F_DUPFD_CLOEXEC, 0);
+ if (stdio == -1) {
+ error.SetErrorToErrno();
+ return error;
+ }
+ SetSTDIOFileDescriptor(stdio);
+ }
SetID(m_monitor->GetPID());
return error;