Replace deprecated_target_wait_hook by observers

Commit b60cea7 (Make target_wait options use enum flags) broke
deprecated_target_wait_hook usage: there's a commit comment telling
this hook has not been converted.

Rather than trying to mend it, this patch replaces the hook by two
target_wait observers:

target_pre_wait (ptid_t ptid)
target_post_wait (ptid_t event_ptid)

Upon target_wait entry, target_pre_wait is notified with the ptid
passed to target_wait. Upon exit, target_post_wait is notified with
the event ptid returned by target_wait. Should an exception occur,
event_ptid is null_ptid.

This change benefits to Insight (out-of-tree): there's no real use of the
late hook in gdb itself.

1 files changed, 0 insertions, 7 deletions

diff --git a/gdb/top.c b/gdb/top.c
index a94ed5c..7831b4f 100644
--- a/gdb/top.c
+++ b/gdb/top.c
@@ -247,13 +247,6 @@ void (*deprecated_readline_end_hook) (void);
 void (*deprecated_attach_hook) (void);
 void (*deprecated_detach_hook) (void);
 
-/* Called when going to wait for the target.  Usually allows the GUI
-   to run while waiting for target events.  */
-
-ptid_t (*deprecated_target_wait_hook) (ptid_t ptid,
-				       struct target_waitstatus *status,
-				       int options);
-
 /* Used by UI as a wrapper around command execution.  May do various
    things like enabling/disabling buttons, etc...  */