[Qemu-devel] [PATCH v4] Add GDB qAttached support

[Jan Kiszka <jan.kiszka@siemens.com>]

With this patch QEMU handles qAttached request from gdb. When QEMU
replies 1, GDB sends a "detach" command at the end of a debugging
session otherwise GDB sends "kill".

The default value for qAttached is 1 on system emulation and 0 on user
emulation.

Based on original version by Fabien Chouteau.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---

As Fabien dropped his attempt to make this configurable, let's
preserve the value of exposing this feature to gdb statically.

 gdbstub.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/gdbstub.c b/gdbstub.c
index e414ad9..9daee86 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -42,6 +42,12 @@
 #include "sysemu/kvm.h"
 #include "qemu/bitops.h"
 
+#ifdef CONFIG_USER_ONLY
+#define GDB_ATTACHED "0"
+#else
+#define GDB_ATTACHED "1"
+#endif
+
 #ifndef TARGET_CPU_MEMORY_RW_DEBUG
 static inline int target_memory_rw_debug(CPUArchState *env, target_ulong addr,
                                          uint8_t *buf, int len, int is_write)
@@ -2491,6 +2497,10 @@ static int gdb_handle_packet(GDBState *s, const char *line_buf)
             break;
         }
 #endif
+        if (strncmp(p, "Attached", 8) == 0) {
+            put_packet(s, GDB_ATTACHED);
+            break;
+        }
         /* Unrecognised 'q' command.  */
         goto unknown_command;
 
-- 
1.7.3.4