gcc/ada/s-traceb.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                     S Y S T E M . T R A C E B A C K                      --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1999-2003 Free Software Foundation, 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 a method for generating a traceback of the
  35 --  current execution location. The traceback shows the locations of
  36 --  calls in the call chain, up to either the top or a designated
  37 --  number of levels.
  38
  39 pragma Polling (Off);
  40 --  We must turn polling off for this unit, because otherwise we get
  41 --  elaboration circularities with System.Exception_Tables.
  42
  43 package System.Traceback is
  44
  45    ----------------
  46    -- Call_Chain --
  47    ----------------
  48
  49    procedure Call_Chain
  50      (Traceback   : System.Address;
  51       Max_Len     : Natural;
  52       Len         : out Natural;
  53       Exclude_Min : System.Address := System.Null_Address;
  54       Exclude_Max : System.Address := System.Null_Address;
  55       Skip_Frames : Natural := 1);
  56    --  Store up to Max_Len code locations in Traceback, corresponding to
  57    --  the current call chain.
  58    --
  59    --    Traceback is the address of an array of addresses where the
  60    --    result will be stored.
  61    --
  62    --    Max_Len is the length of the Traceback array. If the call chain
  63    --    is longer than this, then additional entries are discarded, and
  64    --    the traceback is missing some of the highest level entries.
  65    --
  66    --    Len is the returned actual number of addresses stored
  67    --    in the Traceback array.
  68    --
  69    --    Exclude_Min/Exclude_Max, if non null, provide a range of addresses
  70    --    to ignore from the computation of the traceback.
  71    --
  72    --    Skip_Frames says how many of the most recent calls should at least
  73    --    be excluded from the result, regardless of the exclusion bounds and
  74    --    starting with this procedure itself: 1 means exclude the frame for
  75    --    this procedure, 2 means 1 + exclude the frame for this procedure's
  76    --    caller, ...
  77    --
  78    --  On return, the Traceback array is filled in, and Len indicates
  79    --  the number of stored entries. The first entry is the most recent
  80    --  call, and the last entry is the highest level call.
  81
  82    function C_Call_Chain
  83      (Traceback : System.Address;
  84       Max_Len   : Natural)
  85       return      Natural;
  86    pragma Export (C, C_Call_Chain, "system__traceback__c_call_chain");
  87    --  Version that can be used directly from C.
  88
  89 end System.Traceback;