gcc/ada/g-exctra.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                  G N A T . E X C E P T I O N _ T R A C E S               --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --            Copyright (C) 2000-2003 Ada Core Technologies, Inc.           --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  19 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  20 -- MA 02111-1307, USA.                                                      --
  21 --                                                                          --
  22 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- GNAT was originally developed  by the GNAT team at  New York University. --
  30 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 --  This package provides an interface allowing to control *automatic* output
  35 --  to standard error upon exception occurrences (as opposed to explicit
  36 --  generation of traceback information using GNAT.Traceback).
  37 --
  38 --  This output includes the basic information associated with the exception
  39 --  (name, message) as well as a backtrace of the call chain at the point
  40 --  where the exception occurred. This backtrace is only output if the call
  41 --  chain information is available, depending if the binder switch dedicated
  42 --  to that purpose has been used or not.
  43 --
  44 --  The default backtrace is in the form of absolute code locations which may
  45 --  be converted to corresponding source locations using the addr2line utility
  46 --  or from within GDB. Please refer to GNAT.Traceback for information about
  47 --  what is necessary to be able to exploit thisg possibility.
  48 --
  49 --  The backtrace output can also be customized by way of a "decorator" which
  50 --  may return any string output in association with a provided call chain.
  51
  52 with GNAT.Traceback; use GNAT.Traceback;
  53
  54 package GNAT.Exception_Traces is
  55
  56    --  The following defines the exact situations in which raises will
  57    --  cause automatic output of trace information.
  58
  59    type Trace_Kind is
  60      (Every_Raise,
  61       --  Denotes the initial raise event for any exception occurrence, either
  62       --  explicit or due to a specific language rule, within the context of a
  63       --  task or not.
  64
  65       Unhandled_Raise
  66       --  Denotes the raise events corresponding to exceptions for which there
  67       --  is no user defined handler, in particular, when a task dies due to an
  68       --  unhandled exception.
  69      );
  70
  71    --  The following procedures can be used to activate and deactivate
  72    --  traces identified by the above trace kind values.
  73
  74    procedure Trace_On (Kind : Trace_Kind);
  75    --  Activate the traces denoted by Kind.
  76
  77    procedure Trace_Off;
  78    --  Stop the tracing requested by the last call to Trace_On.
  79    --  Has no effect if no such call has ever occurred.
  80
  81    --  The following provide the backtrace decorating facilities
  82
  83    type Traceback_Decorator is access
  84      function (Traceback : Tracebacks_Array) return String;
  85    --  A backtrace decorator is a function which returns the string to be
  86    --  output for a call chain provided by way of a tracebacks array.
  87
  88    procedure Set_Trace_Decorator (Decorator : Traceback_Decorator);
  89    --  Set the decorator to be used for future automatic outputs. Restore
  90    --  the default behavior (output of raw addresses) if the provided
  91    --  access value is null.
  92
  93 end GNAT.Exception_Traces;