[PATCH 1/5] gdb: Clean up remote.c:remote_resume

Pedro Alves
2016-02-17T02:44:58Z

Just some refactoring / TLC. Mainly split the old c/s/C/S packet
handling to a separate function.

gdb/ChangeLog:
2016-02-09 Pedro Alves <palves@redhat.com>

* remote.c (remote_resume_with_hc): New function, factored out
from ...
(remote_resume): ... this. Always try vCont first.
(remote_vcont_resume): Rename to ...
(remote_resume_with_vcont): ... this. Bail out if execution
direction is reverse.
---
gdb/remote.c | 113 ++++++++++++++++++++++++++++++++---------------------------
1 file changed, 62 insertions(+), 51 deletions(-)

diff --git a/gdb/remote.c b/gdb/remote.c
index fa97e1e..60e2dda 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -5460,6 +5460,58 @@ append_pending_thread_resumptions (char *p, char *endp, ptid_t ptid)
return p;
}

+/* Set the target running, using the packets that use Hc
+ (c/s/C/S). */
+
+static void
+remote_resume_with_hc (struct target_ops *ops,
+ ptid_t ptid, int step, enum gdb_signal siggnal)
+{
+ struct remote_state *rs = get_remote_state ();
+ struct thread_info *thread;
+ char *buf;
+
+ rs->last_sent_signal = siggnal;
+ rs->last_sent_step = step;
+
+ /* The c/s/C/S resume packets use Hc, so set the continue
+ thread. */
+ if (ptid_equal (ptid, minus_one_ptid))
+ set_continue_thread (any_thread_ptid);
+ else
+ set_continue_thread (ptid);
+
+ ALL_NON_EXITED_THREADS (thread)
+ resume_clear_thread_private_info (thread);
+
+ buf = rs->buf;
+ if (execution_direction == EXEC_REVERSE)
+ {
+ /* We don't pass signals to the target in reverse exec mode. */
+ if (info_verbose && siggnal != GDB_SIGNAL_0)
+ warning (_(" - Can't pass signal %d to target in reverse: ignored."),
+ siggnal);
+
+ if (step && packet_support (PACKET_bs) == PACKET_DISABLE)
+ error (_("Remote reverse-step not supported."));
+ if (!step && packet_support (PACKET_bc) == PACKET_DISABLE)
+ error (_("Remote reverse-continue not supported."));
+
+ strcpy (buf, step ? "bs" : "bc");
+ }
+ else if (siggnal != GDB_SIGNAL_0)
+ {
+ buf[0] = step ? 'S' : 'C';
+ buf[1] = tohex (((int) siggnal >> 4) & 0xf);
+ buf[2] = tohex (((int) siggnal) & 0xf);
+ buf[3] = '\0';
+ }
+ else
+ strcpy (buf, step ? "s" : "c");
+
+ putpkt (buf);
+}
+
/* Resume the remote inferior by using a "vCont" packet. The thread
to be resumed is PTID; STEP and SIGGNAL indicate whether the
resumed thread should be single-stepped and/or signalled. If PTID
@@ -5467,16 +5519,20 @@ append_pending_thread_resumptions (char *p, char *endp, ptid_t ptid)
be stepped and/or signalled is given in the global INFERIOR_PTID.
This function returns non-zero iff it resumes the inferior.

- This function issues a strict subset of all possible vCont commands at the
- moment. */
+ This function issues a strict subset of all possible vCont commands
+ at the moment. */

static int
-remote_vcont_resume (ptid_t ptid, int step, enum gdb_signal siggnal)
+remote_resume_with_vcont (ptid_t ptid, int step, enum gdb_signal siggnal)
{
struct remote_state *rs = get_remote_state ();
char *p;
char *endp;

+ /* No reverse support (yet) for vCont. */
+ if (execution_direction == EXEC_REVERSE)
+ return 0;
+
if (packet_support (PACKET_vCont) == PACKET_SUPPORT_UNKNOWN)
remote_vcont_probe (rs);

@@ -5548,8 +5604,6 @@ remote_resume (struct target_ops *ops,
ptid_t ptid, int step, enum gdb_signal siggnal)
{
struct remote_state *rs = get_remote_state ();
- char *buf;
- struct thread_info *thread;

/* In all-stop, we can't mark REMOTE_ASYNC_GET_PENDING_EVENTS_TOKEN
(explained in remote-notif.c:handle_notification) so
@@ -5560,53 +5614,10 @@ remote_resume (struct target_ops *ops,
if (!target_is_non_stop_p ())
remote_notif_process (rs->notif_state, &notif_client_stop);

- rs->last_sent_signal = siggnal;
- rs->last_sent_step = step;
-
- /* The vCont packet doesn't need to specify threads via Hc. */
- /* No reverse support (yet) for vCont. */
- if (execution_direction != EXEC_REVERSE)
- if (remote_vcont_resume (ptid, step, siggnal))
- goto done;
-
- /* All other supported resume packets do use Hc, so set the continue
- thread. */
- if (ptid_equal (ptid, minus_one_ptid))
- set_continue_thread (any_thread_ptid);
- else
- set_continue_thread (ptid);
-
- ALL_NON_EXITED_THREADS (thread)
- resume_clear_thread_private_info (thread);
-
- buf = rs->buf;
- if (execution_direction == EXEC_REVERSE)
- {
- /* We don't pass signals to the target in reverse exec mode. */
- if (info_verbose && siggnal != GDB_SIGNAL_0)
- warning (_(" - Can't pass signal %d to target in reverse: ignored."),
- siggnal);
-
- if (step && packet_support (PACKET_bs) == PACKET_DISABLE)
- error (_("Remote reverse-step not supported."));
- if (!step && packet_support (PACKET_bc) == PACKET_DISABLE)
- error (_("Remote reverse-continue not supported."));
-
- strcpy (buf, step ? "bs" : "bc");
- }
- else if (siggnal != GDB_SIGNAL_0)
- {
- buf[0] = step ? 'S' : 'C';
- buf[1] = tohex (((int) siggnal >> 4) & 0xf);
- buf[2] = tohex (((int) siggnal) & 0xf);
- buf[3] = '\0';
- }
- else
- strcpy (buf, step ? "s" : "c");
-
- putpkt (buf);
+ /* Prefer vCont, and fallback to s/c/S/C, which use Hc. */
+ if (!remote_resume_with_vcont (ptid, step, siggnal))
+ remote_resume_with_hc (ops, ptid, step, siggnal);

- done:
/* We are about to start executing the inferior, let's register it
with the event loop. NOTE: this is the one place where all the
execution commands end up. We could alternatively do this in each
--
1.9.3