gcc/ada/7straceb.adb

   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 --                                 B o d y                                  --
   8 --                                                                          --
   9 --           Copyright (C) 1999-2003 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 version assumes that System.Machine_State_Operations.Pop_Frame can
  35 --  work with the Info parameter being null.
  36
  37 with System.Machine_State_Operations;
  38
  39 package body System.Traceback is
  40
  41    use System.Machine_State_Operations;
  42
  43    ----------------
  44    -- Call_Chain --
  45    ----------------
  46
  47    procedure Call_Chain
  48      (Traceback : System.Address;
  49       Max_Len   : Natural;
  50       Len       : out Natural;
  51       Exclude_Min : System.Address := System.Null_Address;
  52       Exclude_Max : System.Address := System.Null_Address;
  53       Skip_Frames : Natural := 1)
  54    is
  55       type Tracebacks_Array is array (1 .. Max_Len) of Code_Loc;
  56       pragma Suppress_Initialization (Tracebacks_Array);
  57
  58       M     : Machine_State;
  59       Code  : Code_Loc;
  60
  61       Trace : Tracebacks_Array;
  62       for Trace'Address use Traceback;
  63
  64       N_Skips  : Natural := 0;
  65
  66    begin
  67       M := Allocate_Machine_State;
  68       Set_Machine_State (M);
  69
  70       --  Skip the requested number of frames
  71
  72       loop
  73          Code := Get_Code_Loc (M);
  74          exit when Code = Null_Address or else N_Skips = Skip_Frames;
  75
  76          Pop_Frame (M, System.Null_Address);
  77          N_Skips := N_Skips + 1;
  78       end loop;
  79
  80       --  Now, record the frames outside the exclusion bounds, updating
  81       --  the Len output value along the way.
  82
  83       Len := 0;
  84       loop
  85          Code := Get_Code_Loc (M);
  86          exit when Code = Null_Address or else Len = Max_Len;
  87
  88          if Code < Exclude_Min or else Code > Exclude_Max then
  89             Len := Len + 1;
  90             Trace (Len) := Code;
  91          end if;
  92
  93          Pop_Frame (M, System.Null_Address);
  94       end loop;
  95
  96       Free_Machine_State (M);
  97    end Call_Chain;
  98
  99    ------------------
 100    -- C_Call_Chain --
 101    ------------------
 102
 103    function C_Call_Chain
 104      (Traceback   : System.Address;
 105       Max_Len     : Natural) return Natural
 106    is
 107       Val : Natural;
 108    begin
 109       Call_Chain (Traceback, Max_Len, Val);
 110       return Val;
 111    end C_Call_Chain;
 112
 113 end System.Traceback;