RAII-fy make_cleanup_restore_current_thread & friends

After all the make_cleanup_restore_current_thread fixing, I thought
I'd convert that and its relatives (which are all cleanups) to RAII
classes.

scoped_restore_current_pspace_and_thread was put in a separate file to
avoid a circular dependency.

Tested on x86-64 Fedora 23, native and gdbserver.

gdb/ChangeLog:
2017-05-04  Pedro Alves  <palves@redhat.com>

	* Makefile.in (SFILES): Add progspace-and-thread.c.
	(HFILES_NO_SRCDIR): Add progspace-and-thread.h.
	(COMMON_OBS): Add progspace-and-thread.o.
	* breakpoint.c: Include "progspace-and-thread.h".
	(update_inserted_breakpoint_locations)
	(insert_breakpoint_locations, create_longjmp_master_breakpoint):
	Use scoped_restore_current_pspace_and_thread.
	(create_std_terminate_master_breakpoint): Use
	scoped_restore_current_program_space.
	(remove_breakpoint): Use scoped_restore_current_pspace_and_thread.
	(print_breakpoint_location): Use
	scoped_restore_current_program_space.
	(bp_loc_is_permanent): Use
	scoped_restore_current_pspace_and_thread.
	(resolve_sal_pc): Use scoped_restore_current_pspace_and_thread.
	(download_tracepoint_locations): Use
	scoped_restore_current_pspace_and_thread.
	(breakpoint_re_set): Use scoped_restore_current_pspace_and_thread.
	* exec.c (exec_close_1): Use scoped_restore_current_program_space.
	(enum step_over_calls_kind): Moved from inferior.h.
	(class scoped_restore_current_thread): New class.
	* gdbthread.h (make_cleanup_restore_current_thread): Delete
	declaration.
	(scoped_restore_current_thread): New class.
	* infcmd.c: Include "common/gdb_optional.h".
	(continue_1, proceed_after_attach): Use
	scoped_restore_current_thread.
	(notice_new_inferior): Use scoped_restore_current_thread.
	* inferior.c: Include "progspace-and-thread.h".
	(restore_inferior, save_current_inferior): Delete.
	(add_inferior_command, clone_inferior_command): Use
	scoped_restore_current_pspace_and_thread.
	* inferior.h (scoped_restore_current_inferior): New class.
	* infrun.c: Include "progspace-and-thread.h" and
	"common/gdb_optional.h".
	(follow_fork_inferior): Use
	scoped_restore_current_pspace_and_thread.
	(scoped_restore_exited_inferior): New class.
	(handle_vfork_child_exec_or_exit): Use
	scoped_restore_exited_inferior,
	scoped_restore_current_pspace_and_thread,
	scoped_restore_current_thread and scoped_restore.
	(fetch_inferior_event): Use scoped_restore_current_thread.
	* linespec.c (decode_line_full, decode_line_1): Use
	scoped_restore_current_program_space.
	* mi/mi-main.c: Include "progspace-and-thread.h".
	(exec_continue): Use scoped_restore_current_thread.
	(mi_cmd_exec_run): Use scoped_restore_current_pspace_and_thread.
	(mi_cmd_trace_frame_collected): Use scoped_restore_current_thread.
	* proc-service.c (ps_pglobal_lookup): Use
	scoped_restore_current_program_space.
	* progspace-and-thread.c: New file.
	* progspace-and-thread.h: New file.
	* progspace.c (release_program_space, clone_program_space): Use
	scoped_restore_current_program_space.
	(restore_program_space, save_current_program_space)
	(save_current_space_and_thread): Delete.
	(switch_to_program_space_and_thread): Moved to
	progspace-and-thread.c.
	* progspace.h (save_current_program_space)
	(save_current_space_and_thread): Delete declarations.
	(scoped_restore_current_program_space): New class.
	* remote.c (remote_btrace_maybe_reopen): Use
	scoped_restore_current_thread.
	* symtab.c: Include "progspace-and-thread.h".
	(skip_prologue_sal): Use scoped_restore_current_pspace_and_thread.
	* thread.c (print_thread_info_1): Use
	scoped_restore_current_thread.
	(struct current_thread_cleanup): Delete.
	(do_restore_current_thread_cleanup)
	(restore_current_thread_cleanup_dtor): Rename/convert both to ...
	(scoped_restore_current_thread::~scoped_restore_current_thread):
	... this new dtor.
	(make_cleanup_restore_current_thread): Rename/convert to ...
	(scoped_restore_current_thread::scoped_restore_current_thread):
	... this new ctor.
	(thread_apply_all_command): Use scoped_restore_current_thread.
	(thread_apply_command): Use scoped_restore_current_thread.
	* tracepoint.c (tdump_command): Use scoped_restore_current_thread.
	* varobj.c (value_of_root_1): Use scoped_restore_current_thread.

1 files changed, 33 insertions, 64 deletions

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index e8d8d09..9d6a2f4 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -80,6 +80,7 @@
 #include "mi/mi-common.h"
 #include "extension.h"
 #include <algorithm>
+#include "progspace-and-thread.h"
 
 /* Enums for exception-handling support.  */
 enum exception_event_kind
@@ -3065,7 +3066,7 @@ update_inserted_breakpoint_locations (void)
      there was an error.  */
   tmp_error_stream.puts ("Warning:\n");
 
-  struct cleanup *cleanups = save_current_space_and_thread ();
+  scoped_restore_current_pspace_and_thread restore_pspace_thread;
 
   ALL_BP_LOCATIONS (bl, blp_tmp)
     {
@@ -3101,8 +3102,6 @@ update_inserted_breakpoint_locations (void)
       target_terminal_ours_for_output ();
       error_stream (tmp_error_stream);
     }
-
-  do_cleanups (cleanups);
 }
 
 /* Used when starting or continuing the program.  */
@@ -3124,7 +3123,7 @@ insert_breakpoint_locations (void)
      there was an error.  */
   tmp_error_stream.puts ("Warning:\n");
 
-  struct cleanup *cleanups = save_current_space_and_thread ();
+  scoped_restore_current_pspace_and_thread restore_pspace_thread;
 
   ALL_BP_LOCATIONS (bl, blp_tmp)
     {
@@ -3202,8 +3201,6 @@ You may have requested too many hardware breakpoints/watchpoints.\n");
       target_terminal_ours_for_output ();
       error_stream (tmp_error_stream);
     }
-
-  do_cleanups (cleanups);
 }
 
 /* Used when the program stops.
@@ -3489,9 +3486,8 @@ static void
 create_longjmp_master_breakpoint (void)
 {
   struct program_space *pspace;
-  struct cleanup *old_chain;
 
-  old_chain = save_current_program_space ();
+  scoped_restore_current_program_space restore_pspace;
 
   ALL_PSPACES (pspace)
   {
@@ -3595,8 +3591,6 @@ create_longjmp_master_breakpoint (void)
 	}
     }
   }
-
-  do_cleanups (old_chain);
 }
 
 /* Create a master std::terminate breakpoint.  */
@@ -3604,10 +3598,9 @@ static void
 create_std_terminate_master_breakpoint (void)
 {
   struct program_space *pspace;
-  struct cleanup *old_chain;
   const char *const func_name = "std::terminate()";
 
-  old_chain = save_current_program_space ();
+  scoped_restore_current_program_space restore_pspace;
 
   ALL_PSPACES (pspace)
   {
@@ -3652,8 +3645,6 @@ create_std_terminate_master_breakpoint (void)
       b->enable_state = bp_disabled;
     }
   }
-
-  do_cleanups (old_chain);
 }
 
 /* Install a master breakpoint on the unwinder's debug hook.  */
@@ -4077,9 +4068,6 @@ remove_breakpoint_1 (struct bp_location *bl, enum remove_bp_reason reason)
 static int
 remove_breakpoint (struct bp_location *bl)
 {
-  int ret;
-  struct cleanup *old_chain;
-
   /* BL is never in moribund_locations by our callers.  */
   gdb_assert (bl->owner != NULL);
 
@@ -4087,14 +4075,11 @@ remove_breakpoint (struct bp_location *bl)
      This should not ever happen.  */
   gdb_assert (bl->owner->type != bp_none);
 
-  old_chain = save_current_space_and_thread ();
+  scoped_restore_current_pspace_and_thread restore_pspace_thread;
 
   switch_to_program_space_and_thread (bl->pspace);
 
-  ret = remove_breakpoint_1 (bl, REMOVE_BREAKPOINT);
-
-  do_cleanups (old_chain);
-  return ret;
+  return remove_breakpoint_1 (bl, REMOVE_BREAKPOINT);
 }
 
 /* Clear the "inserted" flag in all breakpoints.  */
@@ -6129,7 +6114,8 @@ print_breakpoint_location (struct breakpoint *b,
 			   struct bp_location *loc)
 {
   struct ui_out *uiout = current_uiout;
-  struct cleanup *old_chain = save_current_program_space ();
+
+  scoped_restore_current_program_space restore_pspace;
 
   if (loc != NULL && loc->shlib_disabled)
     loc = NULL;
@@ -6194,8 +6180,6 @@ print_breakpoint_location (struct breakpoint *b,
 			   bp_location_condition_evaluator (loc));
       uiout->text (")");
     }
-
-  do_cleanups (old_chain);
 }
 
 static const char *
@@ -9071,9 +9055,6 @@ program_breakpoint_here_p (struct gdbarch *gdbarch, CORE_ADDR address)
 static int
 bp_loc_is_permanent (struct bp_location *loc)
 {
-  struct cleanup *cleanup;
-  int retval;
-
   gdb_assert (loc != NULL);
 
   /* If we have a catchpoint or a watchpoint, just return 0.  We should not
@@ -9083,14 +9064,9 @@ bp_loc_is_permanent (struct bp_location *loc)
   if (!breakpoint_address_is_meaningful (loc->owner))
     return 0;
 
-  cleanup = save_current_space_and_thread ();
+  scoped_restore_current_pspace_and_thread restore_pspace_thread;
   switch_to_program_space_and_thread (loc->pspace);
-
-  retval = program_breakpoint_here_p (loc->gdbarch, loc->address);
-
-  do_cleanups (cleanup);
-
-  return retval;
+  return program_breakpoint_here_p (loc->gdbarch, loc->address);
 }
 
 /* Build a command list for the dprintf corresponding to the current
@@ -9974,16 +9950,12 @@ resolve_sal_pc (struct symtab_and_line *sal)
 	         if we have line numbers but no functions (as can
 	         happen in assembly source).  */
 
-	      struct bound_minimal_symbol msym;
-	      struct cleanup *old_chain = save_current_space_and_thread ();
-
+	      scoped_restore_current_pspace_and_thread restore_pspace_thread;
 	      switch_to_program_space_and_thread (sal->pspace);
 
-	      msym = lookup_minimal_symbol_by_pc (sal->pc);
+	      bound_minimal_symbol msym = lookup_minimal_symbol_by_pc (sal->pc);
 	      if (msym.minsym)
 		sal->section = MSYMBOL_OBJ_SECTION (msym.objfile, msym.minsym);
-
-	      do_cleanups (old_chain);
 	    }
 	}
     }
@@ -12177,10 +12149,9 @@ static void
 download_tracepoint_locations (void)
 {
   struct breakpoint *b;
-  struct cleanup *old_chain;
   enum tribool can_download_tracepoint = TRIBOOL_UNKNOWN;
 
-  old_chain = save_current_space_and_thread ();
+  scoped_restore_current_pspace_and_thread restore_pspace_thread;
 
   ALL_TRACEPOINTS (b)
     {
@@ -12224,8 +12195,6 @@ download_tracepoint_locations (void)
       if (bp_location_downloaded)
 	observer_notify_breakpoint_modified (b);
     }
-
-  do_cleanups (old_chain);
 }
 
 /* Swap the insertion/duplication state between two locations.  */
@@ -14506,32 +14475,32 @@ breakpoint_re_set (void)
   struct breakpoint *b, *b_tmp;
   enum language save_language;
   int save_input_radix;
-  struct cleanup *old_chain;
 
   save_language = current_language->la_language;
   save_input_radix = input_radix;
-  old_chain = save_current_space_and_thread ();
-
-  /* Note: we must not try to insert locations until after all
-     breakpoints have been re-set.  Otherwise, e.g., when re-setting
-     breakpoint 1, we'd insert the locations of breakpoint 2, which
-     hadn't been re-set yet, and thus may have stale locations.  */
 
-  ALL_BREAKPOINTS_SAFE (b, b_tmp)
   {
-    /* Format possible error msg.  */
-    char *message = xstrprintf ("Error in re-setting breakpoint %d: ",
-				b->number);
-    struct cleanup *cleanups = make_cleanup (xfree, message);
-    catch_errors (breakpoint_re_set_one, b, message, RETURN_MASK_ALL);
-    do_cleanups (cleanups);
-  }
-  set_language (save_language);
-  input_radix = save_input_radix;
+    scoped_restore_current_pspace_and_thread restore_pspace_thread;
 
-  jit_breakpoint_re_set ();
+    /* Note: we must not try to insert locations until after all
+       breakpoints have been re-set.  Otherwise, e.g., when re-setting
+       breakpoint 1, we'd insert the locations of breakpoint 2, which
+       hadn't been re-set yet, and thus may have stale locations.  */
 
-  do_cleanups (old_chain);
+    ALL_BREAKPOINTS_SAFE (b, b_tmp)
+      {
+	/* Format possible error msg.  */
+	char *message = xstrprintf ("Error in re-setting breakpoint %d: ",
+				    b->number);
+	struct cleanup *cleanups = make_cleanup (xfree, message);
+	catch_errors (breakpoint_re_set_one, b, message, RETURN_MASK_ALL);
+	do_cleanups (cleanups);
+      }
+    set_language (save_language);
+    input_radix = save_input_radix;
+
+    jit_breakpoint_re_set ();
+  }
 
   create_overlay_event_breakpoint ();
   create_longjmp_master_breakpoint ();