gdb/exceptions.h

   1 /* Exception (throw catch) mechanism, for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2017 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 RETURN_MASK_ALL
  52    if the code which calls catch_exceptions is not set up to deal with
  53    a quit which isn't caught.  But if the code can deal with it, it
  54    generally should be RETURN_MASK_ERROR, unless for some reason it is
  55    more useful to abort only the portion of the operation inside the
  56    catch_exceptions.  Note that quit should return to the command line
  57    fairly quickly, even if some further processing is being done.
  58
  59    FIXME; cagney/2001-08-13: The need to override the global UIOUT
  60    builder variable should just go away.  */
  61
  62 struct ui_out;
  63 typedef int (catch_exceptions_ftype) (struct ui_out *ui_out, void *args);
  64 extern int catch_exceptions (struct ui_out *uiout,
  65                              catch_exceptions_ftype *func, void *func_args,
  66                              return_mask mask);
  67 typedef void (catch_exception_ftype) (struct ui_out *ui_out, void *args);
  68 extern int catch_exceptions_with_msg (struct ui_out *uiout,
  69                                       catch_exceptions_ftype *func,
  70                                       void *func_args,
  71                                       char **gdberrmsg,
  72                                       return_mask mask);
  73
  74 /* Compare two exception objects for print equality.  */
  75 extern int exception_print_same (struct gdb_exception e1,
  76                                  struct gdb_exception e2);
  77 #endif