1 /* Exception (throw catch) mechanism, for GDB, the GNU debugger.
3 Copyright (C) 1986-2015 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 const struct gdb_exception exception_none
= { 0, GDB_NO_ERROR
, NULL
};
33 prepare_to_throw_exception (void)
42 struct serial
*gdb_stdout_serial
;
44 if (deprecated_error_begin_hook
)
45 deprecated_error_begin_hook ();
47 if (target_supports_terminal_ours ())
48 target_terminal_ours ();
50 /* We want all output to appear now, before we print the error. We
51 have 3 levels of buffering we have to flush (it's possible that
52 some of these should be changed to flush the lower-level ones
55 /* 1. The _filtered buffer. */
56 if (filtered_printing_initialized ())
59 /* 2. The stdio buffer. */
60 gdb_flush (gdb_stdout
);
61 gdb_flush (gdb_stderr
);
63 /* 3. The system-level buffer. */
64 gdb_stdout_serial
= serial_fdopen (1);
65 if (gdb_stdout_serial
)
67 serial_drain_output (gdb_stdout_serial
);
68 serial_un_fdopen (gdb_stdout_serial
);
71 annotate_error_begin ();
75 print_exception (struct ui_file
*file
, struct gdb_exception e
)
77 /* KLUGE: cagney/2005-01-13: Write the string out one line at a time
78 as that way the MI's behavior is preserved. */
82 for (start
= e
.message
; start
!= NULL
; start
= end
)
84 end
= strchr (start
, '\n');
86 fputs_filtered (start
, file
);
90 ui_file_write (file
, start
, end
- start
);
93 fprintf_filtered (file
, "\n");
95 /* Now append the annotation. */
102 /* Assume that these are all errors. */
106 internal_error (__FILE__
, __LINE__
, _("Bad switch."));
111 exception_print (struct ui_file
*file
, struct gdb_exception e
)
113 if (e
.reason
< 0 && e
.message
!= NULL
)
116 print_exception (file
, e
);
121 exception_fprintf (struct ui_file
*file
, struct gdb_exception e
,
122 const char *prefix
, ...)
124 if (e
.reason
< 0 && e
.message
!= NULL
)
130 /* Print the prefix. */
131 va_start (args
, prefix
);
132 vfprintf_filtered (file
, prefix
, args
);
135 print_exception (file
, e
);
139 /* Call FUNC(UIOUT, FUNC_ARGS) but wrapped within an exception
140 handler. If an exception (enum return_reason) is thrown using
141 throw_exception() than all cleanups installed since
142 catch_exceptions() was entered are invoked, the (-ve) exception
143 value is then returned by catch_exceptions. If FUNC() returns
144 normally (with a positive or zero return value) then that value is
145 returned by catch_exceptions(). It is an internal_error() for
146 FUNC() to return a negative value.
148 See exceptions.h for further usage details.
150 Must not be called with immediate_quit in effect (bad things might
151 happen, say we got a signal in the middle of a memcpy to quit_return).
152 This is an OK restriction; with very few exceptions immediate_quit can
153 be replaced by judicious use of QUIT. */
155 /* MAYBE: cagney/1999-11-05: catch_errors() in conjunction with
156 error() et al. could maintain a set of flags that indicate the
157 current state of each of the longjmp buffers. This would give the
158 longjmp code the chance to detect a longjmp botch (before it gets
159 to longjmperror()). Prior to 1999-11-05 this wasn't possible as
160 code also randomly used a SET_TOP_LEVEL macro that directly
161 initialized the longjmp buffers. */
164 catch_exceptions (struct ui_out
*uiout
,
165 catch_exceptions_ftype
*func
,
169 return catch_exceptions_with_msg (uiout
, func
, func_args
, NULL
, mask
);
173 catch_exceptions_with_msg (struct ui_out
*func_uiout
,
174 catch_exceptions_ftype
*func
,
179 volatile struct gdb_exception exception
;
180 volatile int val
= 0;
181 struct ui_out
*saved_uiout
;
183 /* Save and override the global ``struct ui_out'' builder. */
184 saved_uiout
= current_uiout
;
185 current_uiout
= func_uiout
;
187 TRY_CATCH (exception
, RETURN_MASK_ALL
)
189 val
= (*func
) (current_uiout
, func_args
);
192 /* Restore the global builder. */
193 current_uiout
= saved_uiout
;
195 if (exception
.reason
< 0 && (mask
& RETURN_MASK (exception
.reason
)) == 0)
197 /* The caller didn't request that the event be caught.
199 throw_exception (exception
);
202 exception_print (gdb_stderr
, exception
);
203 gdb_assert (val
>= 0);
204 gdb_assert (exception
.reason
<= 0);
205 if (exception
.reason
< 0)
207 /* If caller wants a copy of the low-level error message, make
208 one. This is used in the case of a silent error whereby the
209 caller may optionally want to issue the message. */
210 if (gdberrmsg
!= NULL
)
212 if (exception
.message
!= NULL
)
213 *gdberrmsg
= xstrdup (exception
.message
);
217 return exception
.reason
;
222 /* This function is superseded by catch_exceptions(). */
225 catch_errors (catch_errors_ftype
*func
, void *func_args
, char *errstring
,
228 volatile int val
= 0;
229 volatile struct gdb_exception exception
;
230 struct ui_out
*saved_uiout
;
232 /* Save the global ``struct ui_out'' builder. */
233 saved_uiout
= current_uiout
;
235 TRY_CATCH (exception
, RETURN_MASK_ALL
)
237 val
= func (func_args
);
240 /* Restore the global builder. */
241 current_uiout
= saved_uiout
;
243 if (exception
.reason
< 0 && (mask
& RETURN_MASK (exception
.reason
)) == 0)
245 /* The caller didn't request that the event be caught.
247 throw_exception (exception
);
250 exception_fprintf (gdb_stderr
, exception
, "%s", errstring
);
251 if (exception
.reason
!= 0)