xref: /dragonfly/contrib/gdb-7/gdb/inf-loop.c (revision 678e8cc6)
1 /* Handling of inferior events for the event loop for GDB, the GNU debugger.
2    Copyright (C) 1999, 2007, 2008, 2009, 2010, 2011
3    Free Software Foundation, Inc.
4    Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
5 
6    This file is part of GDB.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20 
21 #include "defs.h"
22 #include "inferior.h"		/* For fetch_inferior_event.  */
23 #include "target.h"             /* For enum inferior_event_type.  */
24 #include "event-loop.h"
25 #include "event-top.h"
26 #include "inf-loop.h"
27 #include "remote.h"
28 #include "exceptions.h"
29 #include "language.h"
30 #include "gdbthread.h"
31 
32 static int fetch_inferior_event_wrapper (gdb_client_data client_data);
33 
34 void
35 inferior_event_handler_wrapper (gdb_client_data client_data)
36 {
37   inferior_event_handler (INF_QUIT_REQ, client_data);
38 }
39 
40 /* General function to handle events in the inferior.  So far it just
41    takes care of detecting errors reported by select() or poll(),
42    otherwise it assumes that all is OK, and goes on reading data from
43    the fd.  This however may not always be what we want to do.  */
44 void
45 inferior_event_handler (enum inferior_event_type event_type,
46 			gdb_client_data client_data)
47 {
48   struct gdb_exception e;
49   int was_sync = 0;
50 
51   switch (event_type)
52     {
53     case INF_ERROR:
54       printf_unfiltered (_("error detected from target.\n"));
55       pop_all_targets_above (file_stratum, 0);
56       discard_all_intermediate_continuations ();
57       discard_all_continuations ();
58       async_enable_stdin ();
59       break;
60 
61     case INF_REG_EVENT:
62       /* Use catch errors for now, until the inner layers of
63 	 fetch_inferior_event (i.e. readchar) can return meaningful
64 	 error status.  If an error occurs while getting an event from
65 	 the target, just get rid of the target.  */
66       if (!catch_errors (fetch_inferior_event_wrapper,
67 			 client_data, "", RETURN_MASK_ALL))
68 	{
69 	  pop_all_targets_above (file_stratum, 0);
70 	  discard_all_intermediate_continuations ();
71 	  discard_all_continuations ();
72 	  async_enable_stdin ();
73 	  display_gdb_prompt (0);
74 	}
75       break;
76 
77     case INF_EXEC_COMPLETE:
78 
79       if (!non_stop)
80 	{
81 	  /* Unregister the inferior from the event loop.  This is done
82 	     so that when the inferior is not running we don't get
83 	     distracted by spurious inferior output.  */
84 	  if (target_has_execution)
85 	    target_async (NULL, 0);
86 	}
87 
88       /* The call to async_enable_stdin below resets 'sync_execution'.
89 	 However, if sync_execution is 1 now, we also need to show the
90 	 prompt below, so save the current value.  */
91       was_sync = sync_execution;
92       async_enable_stdin ();
93 
94       /* Do all continuations associated with the whole inferior (not
95 	 a particular thread).  */
96       if (!ptid_equal (inferior_ptid, null_ptid))
97 	do_all_inferior_continuations ();
98 
99       /* If we were doing a multi-step (eg: step n, next n), but it
100 	 got interrupted by a breakpoint, still do the pending
101 	 continuations.  The continuation itself is responsible for
102 	 distinguishing the cases.  The continuations are allowed to
103 	 touch the inferior memory, e.g. to remove breakpoints, so run
104 	 them before running breakpoint commands, which may resume the
105 	 target.  */
106       if (non_stop
107 	  && target_has_execution
108 	  && !ptid_equal (inferior_ptid, null_ptid))
109 	do_all_intermediate_continuations_thread (inferior_thread ());
110       else
111 	do_all_intermediate_continuations ();
112 
113       /* Always finish the previous command before running any
114 	 breakpoint commands.  Any stop cancels the previous command.
115 	 E.g. a "finish" or "step-n" command interrupted by an
116 	 unrelated breakpoint is canceled.  */
117       if (non_stop
118 	  && target_has_execution
119 	  && !ptid_equal (inferior_ptid, null_ptid))
120 	do_all_continuations_thread (inferior_thread ());
121       else
122 	do_all_continuations ();
123 
124       if (current_language != expected_language
125 	  && language_mode == language_mode_auto)
126 	language_info (1);	/* Print what changed.  */
127 
128       /* Don't propagate breakpoint commands errors.  Either we're
129 	 stopping or some command resumes the inferior.  The user will
130 	 be informed.  */
131       TRY_CATCH (e, RETURN_MASK_ALL)
132 	{
133 	  bpstat_do_actions ();
134 	}
135 
136       if (!was_sync
137 	  && exec_done_display_p
138 	  && (ptid_equal (inferior_ptid, null_ptid)
139 	      || !is_running (inferior_ptid)))
140 	printf_unfiltered (_("completed.\n"));
141       break;
142 
143     case INF_EXEC_CONTINUE:
144       /* Is there anything left to do for the command issued to
145          complete?  */
146 
147       if (non_stop)
148 	do_all_intermediate_continuations_thread (inferior_thread ());
149       else
150 	do_all_intermediate_continuations ();
151       break;
152 
153     case INF_QUIT_REQ:
154       /* FIXME: ezannoni 1999-10-04.  This call should really be a
155 	 target vector entry, so that it can be used for any kind of
156 	 targets.  */
157       async_remote_interrupt_twice (NULL);
158       break;
159 
160     case INF_TIMER:
161     default:
162       printf_unfiltered (_("Event type not recognized.\n"));
163       break;
164     }
165 }
166 
167 static int
168 fetch_inferior_event_wrapper (gdb_client_data client_data)
169 {
170   fetch_inferior_event (client_data);
171   return 1;
172 }
173