Report more precise error message when attach fails

Summary:
If the remote stub sends a specific error message instead of just a E??
code, we can use this to display a more informative error message
instead of just the generic "unable to attach" message.

I write a test for this using the SB API.
On the console this will show up like:
(lldb) process attach ...
error: attach failed: <STUB-MESSAGE>

if the stub supports error messages, or:
error: attach failed: Error ??

if it doesn't.

Reviewers: jingham, JDevlieghere

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D45573

llvm-svn: 330247

1 files changed, 3 insertions, 5 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
index 9d549ff491b..eafc2eef5b7 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -3804,11 +3804,9 @@ thread_result_t ProcessGDBRemote::AsyncThread(void *arg) {
                     response.GetError() == 0x87) {
                   process->SetExitStatus(-1, "cannot attach to process due to "
                                              "System Integrity Protection");
-                }
-                // E01 code from vAttach means that the attach failed
-                if (::strstr(continue_cstr, "vAttach") != NULL &&
-                    response.GetError() == 0x1) {
-                  process->SetExitStatus(-1, "unable to attach");
+                } else if (::strstr(continue_cstr, "vAttach") != NULL &&
+                           response.GetStatus().Fail()) {
+                  process->SetExitStatus(-1, response.GetStatus().AsCString());
                 } else {
                   process->SetExitStatus(-1, "lost connection");
                 }