Adding Support for Error Strings in Remote Packets

Summary:
This patch adds support for sending strings along with
error codes in the reply packets. The implementation is
based on the feedback recieved in the lldb-dev mailing
list. The patch also adds an extra packet for the client
to query if the server has the capability to provide
strings along with error replys.

Reviewers: labath, jingham, sas, lldb-commits, clayborg

Reviewed By: labath, clayborg

Differential Revision: https://reviews.llvm.org/D34945

llvm-svn: 307768

1 files changed, 23 insertions, 5 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
index 33aed7a43c4..e6fd386b903 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
@@ -86,6 +86,7 @@ GDBRemoteCommunicationClient::GDBRemoteCommunicationClient()
       m_supports_jLoadedDynamicLibrariesInfos(eLazyBoolCalculate),
       m_supports_jGetSharedCacheInfo(eLazyBoolCalculate),
       m_supports_QPassSignals(eLazyBoolCalculate),
+      m_supports_error_string_reply(eLazyBoolCalculate),
       m_supports_qProcessInfoPID(true), m_supports_qfProcessInfo(true),
       m_supports_qUserName(true), m_supports_qGroupName(true),
       m_supports_qThreadStopInfo(true), m_supports_z0(true),
@@ -596,6 +597,21 @@ bool GDBRemoteCommunicationClient::GetThreadExtendedInfoSupported() {
   return m_supports_jThreadExtendedInfo;
 }
 
+void GDBRemoteCommunicationClient::EnableErrorStringInPacket() {
+  if (m_supports_error_string_reply == eLazyBoolCalculate) {
+    StringExtractorGDBRemote response;
+    // We try to enable error strings in remote packets
+    // but if we fail, we just work in the older way.
+    m_supports_error_string_reply = eLazyBoolNo;
+    if (SendPacketAndWaitForResponse("QEnableErrorStrings", response, false) ==
+        PacketResult::Success) {
+      if (response.IsOKResponse()) {
+        m_supports_error_string_reply = eLazyBoolYes;
+      }
+    }
+  }
+}
+
 bool GDBRemoteCommunicationClient::GetLoadedDynamicLibrariesInfosSupported() {
   if (m_supports_jLoadedDynamicLibrariesInfos == eLazyBoolCalculate) {
     StringExtractorGDBRemote response;
@@ -3181,8 +3197,8 @@ GDBRemoteCommunicationClient::SendStartTracePacket(const TraceOptions &options,
                                    true) ==
       GDBRemoteCommunication::PacketResult::Success) {
     if (!response.IsNormalResponse()) {
-      error.SetError(response.GetError(), eErrorTypeGeneric);
-      LLDB_LOG(log, "Target does not support Tracing");
+      error = response.GetStatus();
+      LLDB_LOG(log, "Target does not support Tracing , error {0}", error);
     } else {
       ret_uid = response.GetHexMaxU64(false, LLDB_INVALID_UID);
     }
@@ -3219,7 +3235,7 @@ GDBRemoteCommunicationClient::SendStopTracePacket(lldb::user_id_t uid,
                                    true) ==
       GDBRemoteCommunication::PacketResult::Success) {
     if (!response.IsOKResponse()) {
-      error.SetError(response.GetError(), eErrorTypeGeneric);
+      error = response.GetStatus();
       LLDB_LOG(log, "stop tracing failed");
     }
   } else {
@@ -3234,6 +3250,7 @@ GDBRemoteCommunicationClient::SendStopTracePacket(lldb::user_id_t uid,
 Status GDBRemoteCommunicationClient::SendGetDataPacket(
     lldb::user_id_t uid, lldb::tid_t thread_id,
     llvm::MutableArrayRef<uint8_t> &buffer, size_t offset) {
+
   StreamGDBRemote escaped_packet;
   escaped_packet.PutCString("jTraceBufferRead:");
   return SendGetTraceDataPacket(escaped_packet, uid, thread_id, buffer, offset);
@@ -3242,6 +3259,7 @@ Status GDBRemoteCommunicationClient::SendGetDataPacket(
 Status GDBRemoteCommunicationClient::SendGetMetaDataPacket(
     lldb::user_id_t uid, lldb::tid_t thread_id,
     llvm::MutableArrayRef<uint8_t> &buffer, size_t offset) {
+
   StreamGDBRemote escaped_packet;
   escaped_packet.PutCString("jTraceMetaRead:");
   return SendGetTraceDataPacket(escaped_packet, uid, thread_id, buffer, offset);
@@ -3308,7 +3326,7 @@ GDBRemoteCommunicationClient::SendGetTraceConfigPacket(lldb::user_id_t uid,
                   custom_params_sp));
       }
     } else {
-      error.SetError(response.GetError(), eErrorTypeGeneric);
+      error = response.GetStatus();
     }
   } else {
     LLDB_LOG(log, "failed to send packet");
@@ -3344,7 +3362,7 @@ Status GDBRemoteCommunicationClient::SendGetTraceDataPacket(
       size_t filled_size = response.GetHexBytesAvail(buffer);
       buffer = llvm::MutableArrayRef<uint8_t>(buffer.data(), filled_size);
     } else {
-      error.SetError(response.GetError(), eErrorTypeGeneric);
+      error = response.GetStatus();
       buffer = buffer.slice(buffer.size());
     }
   } else {