From 567420d10895611e03d5ee65e6b24c16a69a6e99 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Fri, 7 Aug 2015 17:23:56 +0100 Subject: [PATCH] remote.c/all-stop: Implement TARGET_WAITKIND_NO_RESUMED and TARGET_WNOHANG Even though "target remote" supports target-async, the all-stop target_wait implementation ignores TARGET_WNOHANG. If the core happens to poll for events and we've already read the stop reply out of the serial/socket, remote_wait_as hangs forever instead of returning an indication that there are no events to process. This can't happen currently, but later changes will trigger this. gdb/ChangeLog: 2015-08-07 Pedro Alves * remote.c (remote_wait_as): If not waiting for a stop reply, return TARGET_WAITKIND_NO_RESUMED. If TARGET_WNOHANG is requested, don't block waiting forever. --- gdb/ChangeLog | 6 ++++++ gdb/remote.c | 13 ++++++++++++- 2 files changed, 18 insertions(+), 1 deletion(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 7bec9c8..5bf3d75 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2015-08-07 Pedro Alves + + * remote.c (remote_wait_as): If not waiting for a stop reply, + return TARGET_WAITKIND_NO_RESUMED. If TARGET_WNOHANG is + requested, don't block waiting forever. + 2015-08-07 Pedro Alves * infrun.c (adjust_pc_after_break): Now takes thread_info and diff --git a/gdb/remote.c b/gdb/remote.c index c047f35..4b5eb8e 100644 --- a/gdb/remote.c +++ b/gdb/remote.c @@ -6267,6 +6267,14 @@ remote_wait_as (ptid_t ptid, struct target_waitstatus *status, int options) { int ret; int is_notif; + int forever = ((options & TARGET_WNOHANG) == 0 + && wait_forever_enabled_p); + + if (!rs->waiting_for_stop_reply) + { + status->kind = TARGET_WAITKIND_NO_RESUMED; + return minus_one_ptid; + } if (!target_is_async_p ()) { @@ -6285,7 +6293,7 @@ remote_wait_as (ptid_t ptid, struct target_waitstatus *status, int options) However, before we do that we need to ensure that the caller knows how to take the target into/out of async mode. */ ret = getpkt_or_notif_sane (&rs->buf, &rs->buf_size, - wait_forever_enabled_p, &is_notif); + forever, &is_notif); if (!target_is_async_p ()) signal (SIGINT, ofunc); @@ -6294,6 +6302,9 @@ remote_wait_as (ptid_t ptid, struct target_waitstatus *status, int options) not interesting. */ if (ret != -1 && is_notif) return minus_one_ptid; + + if (ret == -1 && (options & TARGET_WNOHANG) != 0) + return minus_one_ptid; } buf = rs->buf; -- 2.7.4