1 /* Exception (throw catch) mechanism, for GDB, the GNU debugger.
3 Copyright (C) 1986-2017 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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/>. */
21 #include "exceptions.h"
22 #include "breakpoint.h"
28 #include "gdbthread.h"
30 #include "common/gdb_optional.h"
35 struct ui
*ui
= current_ui
;
36 struct serial
*gdb_stdout_serial
;
38 if (deprecated_error_begin_hook
)
39 deprecated_error_begin_hook ();
41 gdb::optional
<target_terminal::scoped_restore_terminal_state
> term_state
;
42 if (target_supports_terminal_ours ())
44 term_state
.emplace ();
45 target_terminal::ours_for_output ();
48 /* We want all output to appear now, before we print the error. We
49 have 3 levels of buffering we have to flush (it's possible that
50 some of these should be changed to flush the lower-level ones
53 /* 1. The _filtered buffer. */
54 if (filtered_printing_initialized ())
57 /* 2. The stdio buffer. */
58 gdb_flush (gdb_stdout
);
59 gdb_flush (gdb_stderr
);
61 /* 3. The system-level buffer. */
62 gdb_stdout_serial
= serial_fdopen (fileno (ui
->outstream
));
63 if (gdb_stdout_serial
)
65 serial_drain_output (gdb_stdout_serial
);
66 serial_un_fdopen (gdb_stdout_serial
);
69 annotate_error_begin ();
73 print_exception (struct ui_file
*file
, struct gdb_exception e
)
75 /* KLUGE: cagney/2005-01-13: Write the string out one line at a time
76 as that way the MI's behavior is preserved. */
80 for (start
= e
.message
; start
!= NULL
; start
= end
)
82 end
= strchr (start
, '\n');
84 fputs_filtered (start
, file
);
88 ui_file_write (file
, start
, end
- start
);
91 fprintf_filtered (file
, "\n");
93 /* Now append the annotation. */
100 /* Assume that these are all errors. */
104 internal_error (__FILE__
, __LINE__
, _("Bad switch."));
109 exception_print (struct ui_file
*file
, struct gdb_exception e
)
111 if (e
.reason
< 0 && e
.message
!= NULL
)
114 print_exception (file
, e
);
119 exception_fprintf (struct ui_file
*file
, struct gdb_exception e
,
120 const char *prefix
, ...)
122 if (e
.reason
< 0 && e
.message
!= NULL
)
128 /* Print the prefix. */
129 va_start (args
, prefix
);
130 vfprintf_filtered (file
, prefix
, args
);
133 print_exception (file
, e
);
137 /* Call FUNC(UIOUT, FUNC_ARGS) but wrapped within an exception
138 handler. If an exception (enum return_reason) is thrown using
139 throw_exception() than all cleanups installed since
140 catch_exceptions() was entered are invoked, the (-ve) exception
141 value is then returned by catch_exceptions. If FUNC() returns
142 normally (with a positive or zero return value) then that value is
143 returned by catch_exceptions(). It is an internal_error() for
144 FUNC() to return a negative value.
146 See exceptions.h for further usage details. */
148 /* MAYBE: cagney/1999-11-05: catch_errors() in conjunction with
149 error() et al. could maintain a set of flags that indicate the
150 current state of each of the longjmp buffers. This would give the
151 longjmp code the chance to detect a longjmp botch (before it gets
152 to longjmperror()). Prior to 1999-11-05 this wasn't possible as
153 code also randomly used a SET_TOP_LEVEL macro that directly
154 initialized the longjmp buffers. */
157 catch_exceptions (struct ui_out
*uiout
,
158 catch_exceptions_ftype
*func
,
162 return catch_exceptions_with_msg (uiout
, func
, func_args
, NULL
, mask
);
166 catch_exceptions_with_msg (struct ui_out
*func_uiout
,
167 catch_exceptions_ftype
*func
,
172 struct gdb_exception exception
= exception_none
;
173 volatile int val
= 0;
174 struct ui_out
*saved_uiout
;
176 /* Save and override the global ``struct ui_out'' builder. */
177 saved_uiout
= current_uiout
;
178 current_uiout
= func_uiout
;
182 val
= (*func
) (current_uiout
, func_args
);
184 CATCH (ex
, RETURN_MASK_ALL
)
190 /* Restore the global builder. */
191 current_uiout
= saved_uiout
;
193 if (exception
.reason
< 0 && (mask
& RETURN_MASK (exception
.reason
)) == 0)
195 /* The caller didn't request that the event be caught.
197 throw_exception (exception
);
200 exception_print (gdb_stderr
, exception
);
201 gdb_assert (val
>= 0);
202 gdb_assert (exception
.reason
<= 0);
203 if (exception
.reason
< 0)
205 /* If caller wants a copy of the low-level error message, make
206 one. This is used in the case of a silent error whereby the
207 caller may optionally want to issue the message. */
208 if (gdberrmsg
!= NULL
)
210 if (exception
.message
!= NULL
)
211 *gdberrmsg
= xstrdup (exception
.message
);
215 return exception
.reason
;
220 /* See exceptions.h. */
223 exception_print_same (struct gdb_exception e1
, struct gdb_exception e2
)
225 const char *msg1
= e1
.message
;
226 const char *msg2
= e2
.message
;
233 return (e1
.reason
== e2
.reason
234 && e1
.error
== e2
.error
235 && strcmp (msg1
, msg2
) == 0);