Don't ever reduce the timeout of a packet, only increase it.

Differential Revision: https://reviews.llvm.org/D32087

llvm-svn: 300455

2 files changed, 15 insertions, 3 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
index 7ef253decad..d527b4daaab 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
@@ -1310,12 +1310,20 @@ void GDBRemoteCommunication::DumpHistory(Stream &strm) { m_history.Dump(strm); }
 
 GDBRemoteCommunication::ScopedTimeout::ScopedTimeout(
     GDBRemoteCommunication &gdb_comm, std::chrono::seconds timeout)
-    : m_gdb_comm(gdb_comm) {
-  m_saved_timeout = m_gdb_comm.SetPacketTimeout(timeout);
+  : m_gdb_comm(gdb_comm), m_timeout_modified(false) {
+    auto curr_timeout = gdb_comm.GetPacketTimeout();
+    // Only update the timeout if the timeout is greater than the current
+    // timeout. If the current timeout is larger, then just use that.
+    if (curr_timeout < timeout) {
+      m_timeout_modified = true;
+      m_saved_timeout = m_gdb_comm.SetPacketTimeout(timeout);
+    }
 }
 
 GDBRemoteCommunication::ScopedTimeout::~ScopedTimeout() {
-  m_gdb_comm.SetPacketTimeout(m_saved_timeout);
+  // Only restore the timeout if we set it in the constructor.
+  if (m_timeout_modified)
+    m_gdb_comm.SetPacketTimeout(m_saved_timeout);
 }
 
 // This function is called via the Communications class read thread when bytes
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.h b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.h
index 1f3fa17cfc2..b49e05e22d9 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.h
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.h
@@ -89,6 +89,10 @@ public:
   private:
     GDBRemoteCommunication &m_gdb_comm;
     std::chrono::seconds m_saved_timeout;
+    // Don't ever reduce the timeout for a packet, only increase it. If the
+    // requested timeout if less than the current timeout, we don't set it
+    // and won't need to restore it.
+    bool m_timeout_modified;
   };
 
   GDBRemoteCommunication(const char *comm_name, const char *listener_name);