xref: /dragonfly/contrib/gdb-7/gdb/inf-loop.c (revision dcd37f7d)
1 /* Handling of inferior events for the event loop for GDB, the GNU debugger.
2    Copyright (C) 1999, 2007, 2008, 2009 Free Software Foundation, Inc.
3    Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
4 
5    This file is part of GDB.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>. */
19 
20 #include "defs.h"
21 #include "inferior.h"		/* For fetch_inferior_event. */
22 #include "target.h"             /* For enum inferior_event_type. */
23 #include "event-loop.h"
24 #include "event-top.h"
25 #include "inf-loop.h"
26 #include "remote.h"
27 #include "exceptions.h"
28 #include "language.h"
29 #include "gdbthread.h"
30 
31 static int fetch_inferior_event_wrapper (gdb_client_data client_data);
32 
33 void
34 inferior_event_handler_wrapper (gdb_client_data client_data)
35 {
36   inferior_event_handler (INF_QUIT_REQ, client_data);
37 }
38 
39 /* General function to handle events in the inferior. So far it just
40    takes care of detecting errors reported by select() or poll(),
41    otherwise it assumes that all is OK, and goes on reading data from
42    the fd. This however may not always be what we want to do. */
43 void
44 inferior_event_handler (enum inferior_event_type event_type,
45 			gdb_client_data client_data)
46 {
47   struct gdb_exception e;
48   int was_sync = 0;
49   switch (event_type)
50     {
51     case INF_ERROR:
52       printf_unfiltered (_("error detected from target.\n"));
53       pop_all_targets_above (file_stratum, 0);
54       discard_all_intermediate_continuations ();
55       discard_all_continuations ();
56       async_enable_stdin ();
57       break;
58 
59     case INF_REG_EVENT:
60       /* Use catch errors for now, until the inner layers of
61 	 fetch_inferior_event (i.e. readchar) can return meaningful
62 	 error status.  If an error occurs while getting an event from
63 	 the target, just get rid of the target. */
64       if (!catch_errors (fetch_inferior_event_wrapper,
65 			 client_data, "", RETURN_MASK_ALL))
66 	{
67 	  pop_all_targets_above (file_stratum, 0);
68 	  discard_all_intermediate_continuations ();
69 	  discard_all_continuations ();
70 	  async_enable_stdin ();
71 	  display_gdb_prompt (0);
72 	}
73       break;
74 
75     case INF_EXEC_COMPLETE:
76 
77       if (!non_stop)
78 	{
79 	  /* Unregister the inferior from the event loop. This is done
80 	     so that when the inferior is not running we don't get
81 	     distracted by spurious inferior output.  */
82 	  if (target_has_execution)
83 	    target_async (NULL, 0);
84 	}
85 
86       /* The call to async_enable_stdin below resets 'sync_execution'.
87 	 However, if sync_execution is 1 now, we also need to show the
88 	 prompt below, so save the current value.  */
89       was_sync = sync_execution;
90       async_enable_stdin ();
91 
92       /* Do all continuations associated with the whole inferior (not
93 	 a particular thread).  */
94       if (!ptid_equal (inferior_ptid, null_ptid))
95 	do_all_inferior_continuations ();
96 
97       /* If we were doing a multi-step (eg: step n, next n), but it
98 	 got interrupted by a breakpoint, still do the pending
99 	 continuations.  The continuation itself is responsible for
100 	 distinguishing the cases.  The continuations are allowed to
101 	 touch the inferior memory, e.g. to remove breakpoints, so run
102 	 them before running breakpoint commands, which may resume the
103 	 target.  */
104       if (non_stop
105 	  && target_has_execution
106 	  && !ptid_equal (inferior_ptid, null_ptid))
107 	do_all_intermediate_continuations_thread (inferior_thread ());
108       else
109 	do_all_intermediate_continuations ();
110 
111       /* Always finish the previous command before running any
112 	 breakpoint commands.  Any stop cancels the previous command.
113 	 E.g. a "finish" or "step-n" command interrupted by an
114 	 unrelated breakpoint is canceled.  */
115       if (non_stop
116 	  && target_has_execution
117 	  && !ptid_equal (inferior_ptid, null_ptid))
118 	do_all_continuations_thread (inferior_thread ());
119       else
120 	do_all_continuations ();
121 
122       if (current_language != expected_language
123 	  && language_mode == language_mode_auto)
124 	language_info (1);	/* Print what changed.  */
125 
126       /* Don't propagate breakpoint commands errors.  Either we're
127 	 stopping or some command resumes the inferior.  The user will
128 	 be informed.  */
129       TRY_CATCH (e, RETURN_MASK_ALL)
130 	{
131 	  bpstat_do_actions ();
132 	}
133 
134       if (!was_sync
135 	  && exec_done_display_p
136 	  && (ptid_equal (inferior_ptid, null_ptid)
137 	      || !is_running (inferior_ptid)))
138 	printf_unfiltered (_("completed.\n"));
139       break;
140 
141     case INF_EXEC_CONTINUE:
142       /* Is there anything left to do for the command issued to
143          complete? */
144 
145       if (non_stop)
146 	do_all_intermediate_continuations_thread (inferior_thread ());
147       else
148 	do_all_intermediate_continuations ();
149       break;
150 
151     case INF_QUIT_REQ:
152       /* FIXME: ezannoni 1999-10-04. This call should really be a
153 	 target vector entry, so that it can be used for any kind of
154 	 targets. */
155       async_remote_interrupt_twice (NULL);
156       break;
157 
158     case INF_TIMER:
159     default:
160       printf_unfiltered (_("Event type not recognized.\n"));
161       break;
162     }
163 }
164 
165 static int
166 fetch_inferior_event_wrapper (gdb_client_data client_data)
167 {
168   fetch_inferior_event (client_data);
169   return 1;
170 }
171