xref: /netbsd-src/external/gpl3/gdb/dist/gdb/exceptions.h (revision e89934bbf778a6d6d6894877c4da59d0c7835b0f)
1 /* Exception (throw catch) mechanism, for GDB, the GNU debugger.
2 
3    Copyright (C) 1986-2016 Free Software Foundation, Inc.
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 #ifndef EXCEPTIONS_H
21 #define EXCEPTIONS_H
22 
23 #include "ui-out.h"
24 
25 /* If E is an exception, print it's error message on the specified
26    stream.  For _fprintf, prefix the message with PREFIX...  */
27 extern void exception_print (struct ui_file *file, struct gdb_exception e);
28 extern void exception_fprintf (struct ui_file *file, struct gdb_exception e,
29 			       const char *prefix,
30 			       ...) ATTRIBUTE_PRINTF (3, 4);
31 
32 /* Call FUNC(UIOUT, FUNC_ARGS) but wrapped within an exception
33    handler.  If an exception (enum return_reason) is thrown using
34    throw_exception() than all cleanups installed since
35    catch_exceptions() was entered are invoked, the (-ve) exception
36    value is then returned by catch_exceptions.  If FUNC() returns
37    normally (with a positive or zero return value) then that value is
38    returned by catch_exceptions().  It is an internal_error() for
39    FUNC() to return a negative value.
40 
41    For the period of the FUNC() call: UIOUT is installed as the output
42    builder; ERRSTRING is installed as the error/quit message; and a
43    new cleanup_chain is established.  The old values are restored
44    before catch_exceptions() returns.
45 
46    The variant catch_exceptions_with_msg() is the same as
47    catch_exceptions() but adds the ability to return an allocated
48    copy of the gdb error message.  This is used when a silent error is
49    issued and the caller wants to manually issue the error message.
50 
51    MASK specifies what to catch; it is normally set to
52    RETURN_MASK_ALL, if for no other reason than that the code which
53    calls catch_errors might not be set up to deal with a quit which
54    isn't caught.  But if the code can deal with it, it generally
55    should be RETURN_MASK_ERROR, unless for some reason it is more
56    useful to abort only the portion of the operation inside the
57    catch_errors.  Note that quit should return to the command line
58    fairly quickly, even if some further processing is being done.
59 
60    FIXME; cagney/2001-08-13: The need to override the global UIOUT
61    builder variable should just go away.
62 
63    This function supersedes catch_errors().
64 
65    This function uses SETJMP() and LONGJUMP().  */
66 
67 struct ui_out;
68 typedef int (catch_exceptions_ftype) (struct ui_out *ui_out, void *args);
69 extern int catch_exceptions (struct ui_out *uiout,
70 			     catch_exceptions_ftype *func, void *func_args,
71 			     return_mask mask);
72 typedef void (catch_exception_ftype) (struct ui_out *ui_out, void *args);
73 extern int catch_exceptions_with_msg (struct ui_out *uiout,
74 			     	      catch_exceptions_ftype *func,
75 			     	      void *func_args,
76 			     	      char **gdberrmsg,
77 				      return_mask mask);
78 
79 /* If CATCH_ERRORS_FTYPE throws an error, catch_errors() returns zero
80    otherwize the result from CATCH_ERRORS_FTYPE is returned.  It is
81    probably useful for CATCH_ERRORS_FTYPE to always return a non-zero
82    value.  It's unfortunate that, catch_errors() does not return an
83    indication of the exact exception that it caught - quit_flag might
84    help.
85 
86    This function is superseded by catch_exceptions().  */
87 
88 typedef int (catch_errors_ftype) (void *);
89 extern int catch_errors (catch_errors_ftype *, void *, char *, return_mask);
90 
91 #endif
92