RAII-fy make_cleanup_restore_current_thread & friends

[external/binutils.git] / gdb / infrun.c

diff --git a/gdb/infrun.c b/gdb/infrun.c
index fcafdc1..d0504de 100644 (file)
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -64,6 +64,8 @@
 #include "event-loop.h"
 #include "thread-fsm.h"
 #include "common/enum-flags.h"
+#include "progspace-and-thread.h"
+#include "common/gdb_optional.h"
 
 /* Prototypes for local functions */
 
@@ -487,7 +489,6 @@ holding the child stopped.  Try \"set detach-on-fork\" or \
       else
        {
          struct inferior *parent_inf, *child_inf;
-         struct cleanup *old_chain;
 
          /* Add process to GDB's tables.  */
          child_inf = add_inferior (ptid_get_pid (child_ptid));
@@ -498,7 +499,7 @@ holding the child stopped.  Try \"set detach-on-fork\" or \
          child_inf->gdbarch = parent_inf->gdbarch;
          copy_inferior_target_desc_info (child_inf, parent_inf);
 
-         old_chain = save_current_space_and_thread ();
+         scoped_restore_current_pspace_and_thread restore_pspace_thread;
 
          inferior_ptid = child_ptid;
          add_thread (inferior_ptid);
@@ -536,8 +537,6 @@ holding the child stopped.  Try \"set detach-on-fork\" or \
                 required.  */
              solib_create_inferior_hook (0);
            }
-
-         do_cleanups (old_chain);
        }
 
       if (has_vforked)
@@ -895,6 +894,22 @@ proceed_after_vfork_done (struct thread_info *thread,
   return 0;
 }
 
+/* Save/restore inferior_ptid, current program space and current
+   inferior.  Only use this if the current context points at an exited
+   inferior (and therefore there's no current thread to save).  */
+class scoped_restore_exited_inferior
+{
+public:
+  scoped_restore_exited_inferior ()
+    : m_saved_ptid (&inferior_ptid)
+  {}
+
+private:
+  scoped_restore_tmpl<ptid_t> m_saved_ptid;
+  scoped_restore_current_program_space m_pspace;
+  scoped_restore_current_inferior m_inferior;
+};
+
 /* Called whenever we notice an exec or exit event, to handle
    detaching or resuming a vfork parent.  */
 
@@ -914,7 +929,6 @@ handle_vfork_child_exec_or_exit (int exec)
       if (inf->vfork_parent->pending_detach)
        {
          struct thread_info *tp;
-         struct cleanup *old_chain;
          struct program_space *pspace;
          struct address_space *aspace;
 
@@ -922,16 +936,17 @@ handle_vfork_child_exec_or_exit (int exec)
 
          inf->vfork_parent->pending_detach = 0;
 
+         gdb::optional<scoped_restore_exited_inferior>
+           maybe_restore_inferior;
+         gdb::optional<scoped_restore_current_pspace_and_thread>
+           maybe_restore_thread;
+
+         /* If we're handling a child exit, then inferior_ptid points
+            at the inferior's pid, not to a thread.  */
          if (!exec)
-           {
-             /* If we're handling a child exit, then inferior_ptid
-                points at the inferior's pid, not to a thread.  */
-             old_chain = save_inferior_ptid ();
-             save_current_program_space ();
-             save_current_inferior ();
-           }
+           maybe_restore_inferior.emplace ();
          else
-           old_chain = save_current_space_and_thread ();
+           maybe_restore_thread.emplace ();
 
          /* We're letting loose of the parent.  */
          tp = any_live_thread_of_process (inf->vfork_parent->pid);
@@ -979,8 +994,6 @@ handle_vfork_child_exec_or_exit (int exec)
          /* Put it back.  */
          inf->pspace = pspace;
          inf->aspace = aspace;
-
-         do_cleanups (old_chain);
        }
       else if (exec)
        {
@@ -998,7 +1011,6 @@ handle_vfork_child_exec_or_exit (int exec)
        }
       else
        {
-         struct cleanup *old_chain;
          struct program_space *pspace;
 
          /* If this is a vfork child exiting, then the pspace and
@@ -1010,10 +1022,11 @@ handle_vfork_child_exec_or_exit (int exec)
             go ahead and create a new one for this exiting
             inferior.  */
 
-         /* Switch to null_ptid, so that clone_program_space doesn't want
-            to read the selected frame of a dead process.  */
-         old_chain = save_inferior_ptid ();
-         inferior_ptid = null_ptid;
+         /* Switch to null_ptid while running clone_program_space, so
+            that clone_program_space doesn't want to read the
+            selected frame of a dead process.  */
+         scoped_restore restore_ptid
+           = make_scoped_restore (&inferior_ptid, null_ptid);
 
          /* This inferior is dead, so avoid giving the breakpoints
             module the option to write through to it (cloning a
@@ -1028,10 +1041,6 @@ handle_vfork_child_exec_or_exit (int exec)
          inf->pspace = pspace;
          inf->aspace = pspace->aspace;
 
-         /* Put back inferior_ptid.  We'll continue mourning this
-            inferior.  */
-         do_cleanups (old_chain);
-
          resume_parent = inf->vfork_parent->pid;
          /* Break the bonds.  */
          inf->vfork_parent->vfork_child = NULL;
@@ -1045,7 +1054,7 @@ handle_vfork_child_exec_or_exit (int exec)
        {
          /* If the user wanted the parent to be running, let it go
             free now.  */
-         struct cleanup *old_chain = make_cleanup_restore_current_thread ();
+         scoped_restore_current_thread restore_thread;
 
          if (debug_infrun)
            fprintf_unfiltered (gdb_stdlog,
@@ -1053,8 +1062,6 @@ handle_vfork_child_exec_or_exit (int exec)
                                resume_parent);
 
          iterate_over_threads (proceed_after_vfork_done, &resume_parent);
-
-         do_cleanups (old_chain);
        }
     }
 }
@@ -3889,12 +3896,14 @@ fetch_inferior_event (void *client_data)
       set_current_traceframe (-1);
     }
 
+  gdb::optional<scoped_restore_current_thread> maybe_restore_thread;
+
   if (non_stop)
     /* In non-stop mode, the user/frontend should not notice a thread
        switch due to internal events.  Make sure we reverse to the
        user selected thread and frame after handling the event and
        running any breakpoint commands.  */
-    make_cleanup_restore_current_thread ();
+    maybe_restore_thread.emplace ();
 
   overlay_cache_invalid = 1;
   /* Flush target cache before starting to handle each event.  Target