xref: /dragonfly/contrib/gdb-7/gdb/inf-loop.c (revision 2b23d27f)
1 /* Handling of inferior events for the event loop for GDB, the GNU debugger.
2    Copyright (C) 1999, 2007, 2008, 2009, 2010 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 
50   switch (event_type)
51     {
52     case INF_ERROR:
53       printf_unfiltered (_("error detected from target.\n"));
54       pop_all_targets_above (file_stratum, 0);
55       discard_all_intermediate_continuations ();
56       discard_all_continuations ();
57       async_enable_stdin ();
58       break;
59 
60     case INF_REG_EVENT:
61       /* Use catch errors for now, until the inner layers of
62 	 fetch_inferior_event (i.e. readchar) can return meaningful
63 	 error status.  If an error occurs while getting an event from
64 	 the target, just get rid of the target. */
65       if (!catch_errors (fetch_inferior_event_wrapper,
66 			 client_data, "", RETURN_MASK_ALL))
67 	{
68 	  pop_all_targets_above (file_stratum, 0);
69 	  discard_all_intermediate_continuations ();
70 	  discard_all_continuations ();
71 	  async_enable_stdin ();
72 	  display_gdb_prompt (0);
73 	}
74       break;
75 
76     case INF_EXEC_COMPLETE:
77 
78       if (!non_stop)
79 	{
80 	  /* Unregister the inferior from the event loop. This is done
81 	     so that when the inferior is not running we don't get
82 	     distracted by spurious inferior output.  */
83 	  if (target_has_execution)
84 	    target_async (NULL, 0);
85 	}
86 
87       /* The call to async_enable_stdin below resets 'sync_execution'.
88 	 However, if sync_execution is 1 now, we also need to show the
89 	 prompt below, so save the current value.  */
90       was_sync = sync_execution;
91       async_enable_stdin ();
92 
93       /* Do all continuations associated with the whole inferior (not
94 	 a particular thread).  */
95       if (!ptid_equal (inferior_ptid, null_ptid))
96 	do_all_inferior_continuations ();
97 
98       /* If we were doing a multi-step (eg: step n, next n), but it
99 	 got interrupted by a breakpoint, still do the pending
100 	 continuations.  The continuation itself is responsible for
101 	 distinguishing the cases.  The continuations are allowed to
102 	 touch the inferior memory, e.g. to remove breakpoints, so run
103 	 them before running breakpoint commands, which may resume the
104 	 target.  */
105       if (non_stop
106 	  && target_has_execution
107 	  && !ptid_equal (inferior_ptid, null_ptid))
108 	do_all_intermediate_continuations_thread (inferior_thread ());
109       else
110 	do_all_intermediate_continuations ();
111 
112       /* Always finish the previous command before running any
113 	 breakpoint commands.  Any stop cancels the previous command.
114 	 E.g. a "finish" or "step-n" command interrupted by an
115 	 unrelated breakpoint is canceled.  */
116       if (non_stop
117 	  && target_has_execution
118 	  && !ptid_equal (inferior_ptid, null_ptid))
119 	do_all_continuations_thread (inferior_thread ());
120       else
121 	do_all_continuations ();
122 
123       if (current_language != expected_language
124 	  && language_mode == language_mode_auto)
125 	language_info (1);	/* Print what changed.  */
126 
127       /* Don't propagate breakpoint commands errors.  Either we're
128 	 stopping or some command resumes the inferior.  The user will
129 	 be informed.  */
130       TRY_CATCH (e, RETURN_MASK_ALL)
131 	{
132 	  bpstat_do_actions ();
133 	}
134 
135       if (!was_sync
136 	  && exec_done_display_p
137 	  && (ptid_equal (inferior_ptid, null_ptid)
138 	      || !is_running (inferior_ptid)))
139 	printf_unfiltered (_("completed.\n"));
140       break;
141 
142     case INF_EXEC_CONTINUE:
143       /* Is there anything left to do for the command issued to
144          complete? */
145 
146       if (non_stop)
147 	do_all_intermediate_continuations_thread (inferior_thread ());
148       else
149 	do_all_intermediate_continuations ();
150       break;
151 
152     case INF_QUIT_REQ:
153       /* FIXME: ezannoni 1999-10-04. This call should really be a
154 	 target vector entry, so that it can be used for any kind of
155 	 targets. */
156       async_remote_interrupt_twice (NULL);
157       break;
158 
159     case INF_TIMER:
160     default:
161       printf_unfiltered (_("Event type not recognized.\n"));
162       break;
163     }
164 }
165 
166 static int
167 fetch_inferior_event_wrapper (gdb_client_data client_data)
168 {
169   fetch_inferior_event (client_data);
170   return 1;
171 }
172