Make linux_nat_detach/thread_db_detach use the inferior parameter

This patch makes these two functions actually use the inferior parameter
added by the previous patch, instead of reading inferior_ptid.  I chose
these two, because they are the one actually used when I detach on my
GNU/Linux system, so they were easy to test.

I took the opportunity to pass the inferior being detached to
inf_ptrace_detach_success, so it could use it too.  From there, it made
sense to add an overload of detach_inferior that takes the inferior
directly rather than the pid, to avoid having to pass inf->pid only for
the callee to look up the inferior structure by pid.

gdb/ChangeLog:

	* inf-ptrace.c (inf_ptrace_detach): Adjust call to
	inf_ptrace_detach_success.
	(inf_ptrace_detach_success): Add inferior parameter, use it
	instead of inferior_ptid, pass it to detach_inferior.
	* inf-ptrace.h (inf_ptrace_detach_success): Add inferior
	parameter.
	* inferior.c (detach_inferior): Add overload that takes an
	inferior object.
	* inferior.h (detach_inferior): Likewise.
	* linux-nat.c (linux_nat_detach): Use the inf parameter, don't
	use inferior_ptid, adjust call to inf_ptrace_detach_success.
	* linux-thread-db.c (thread_db_detach): Use inf parameter.

1 files changed, 3 insertions, 5 deletions

diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index aa8b17f..72aa334 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -263,18 +263,16 @@ inf_ptrace_detach (struct target_ops *ops, inferior *inf, int from_tty)
   error (_("This system does not support detaching from a process"));
 #endif
 
-  inf_ptrace_detach_success (ops);
+  inf_ptrace_detach_success (ops, inf);
 }
 
 /* See inf-ptrace.h.  */
 
 void
-inf_ptrace_detach_success (struct target_ops *ops)
+inf_ptrace_detach_success (struct target_ops *ops, inferior *inf)
 {
-  pid_t pid = ptid_get_pid (inferior_ptid);
-
   inferior_ptid = null_ptid;
-  detach_inferior (pid);
+  detach_inferior (inf);
 
   inf_child_maybe_unpush_target (ops);
 }