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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- A D A . E X C E P T I O N S . L A S T _ C H A N C E _ H A N D L E R --
-- --
-- B o d y --
-- --
-- Copyright (C) 2003 Free Software Foundation, Inc. --
-- --
-- This specification is derived from the Ada Reference Manual for use with --
-- GNAT. The copyright notice above, and the license provisions that follow --
-- apply solely to the contents of the part following the private keyword. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 2, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, USA. --
-- --
-- As a special exception, if other files instantiate generics from this --
-- unit, or you link this unit with other files to produce an executable, --
-- this unit does not by itself cause the resulting executable to be --
-- covered by the GNU General Public License. This exception does not --
-- however invalidate any other reasons why the executable file might be --
-- covered by the GNU Public License. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- Default version for most targets
procedure Ada.Exceptions.Last_Chance_Handler
(Except : Exception_Occurrence)
is
procedure Unhandled_Terminate;
pragma No_Return (Unhandled_Terminate);
pragma Import (C, Unhandled_Terminate, "__gnat_unhandled_terminate");
-- Perform system dependent shutdown code
function Tailored_Exception_Information
(X : Exception_Occurrence) return String;
-- Exception information to be output in the case of automatic tracing
-- requested through GNAT.Exception_Traces.
--
-- This is the same as Exception_Information if no backtrace decorator
-- is currently in place. Otherwise, this is Exception_Information with
-- the call chain raw addresses replaced by the result of a call to the
-- current decorator provided with the call chain addresses.
pragma Import
(Ada, Tailored_Exception_Information,
"__gnat_tailored_exception_information");
procedure Tailored_Exception_Information
(X : Exception_Occurrence;
Buff : in out String;
Last : in out Integer);
-- Procedural version of the above function. Instead of returning the
-- result, this one is put in Buff (Buff'first .. Buff'first + Last)
procedure To_Stderr (S : String);
pragma Import (Ada, To_Stderr, "__gnat_to_stderr");
-- Little routine to output string to stderr
Nline : constant String := String'(1 => ASCII.LF);
-- Convenient shortcut
Msg : constant String := Except.Msg (1 .. Except.Msg_Length);
Max_Static_Exc_Info : constant := 1024;
-- This should be enough for most exception information cases
-- even though tailoring introduces some uncertainty. The
-- name+message should not exceed 320 chars, so that leaves at
-- least 35 backtrace slots (each slot needs 19 chars for
-- representing a 64 bit address).
subtype Exc_Info_Type is String (1 .. Max_Static_Exc_Info);
type Str_Ptr is access Exc_Info_Type;
Exc_Info : Str_Ptr;
Exc_Info_Last : Natural := 0;
-- Buffer that is allocated to store the tailored exception
-- information while Adafinal is run. This buffer is allocated
-- on the heap only when it is needed. It is better to allocate
-- on the heap than on the stack since stack overflows are more
-- common than heap overflows.
procedure Tailored_Exception_Information
(X : Exception_Occurrence;
Buff : in out String;
Last : in out Integer)
is
Info : constant String := Tailored_Exception_Information (X);
begin
Last := Info'Last;
Buff (1 .. Last) := Info;
end Tailored_Exception_Information;
begin
-- First allocate & store the exception info in a buffer when
-- we know it will be needed. This needs to be done before
-- Adafinal because it implicitly uses the secondary stack.
if Except.Id.Full_Name.all (1) /= '_'
and then Except.Num_Tracebacks /= 0
then
Exc_Info := new Exc_Info_Type;
if Exc_Info /= null then
Tailored_Exception_Information
(Except, Exc_Info.all, Exc_Info_Last);
end if;
end if;
-- Let's shutdown the runtime now. The rest of the procedure
-- needs to be careful not to use anything that would require
-- runtime support. In particular, functions returning strings
-- are banned since the sec stack is no longer functional.
System.Standard_Library.Adafinal;
-- Check for special case of raising _ABORT_SIGNAL, which is not
-- really an exception at all. We recognize this by the fact that
-- it is the only exception whose name starts with underscore.
if Except.Id.Full_Name.all (1) = '_' then
To_Stderr (Nline);
To_Stderr ("Execution terminated by abort of environment task");
To_Stderr (Nline);
-- If no tracebacks, we print the unhandled exception in the old style
-- (i.e. the style used before ZCX was implemented). We do this to
-- retain compatibility.
elsif Except.Num_Tracebacks = 0 then
To_Stderr (Nline);
To_Stderr ("raised ");
To_Stderr (Except.Id.Full_Name.all (1 .. Except.Id.Name_Length - 1));
if Msg'Length /= 0 then
To_Stderr (" : ");
To_Stderr (Msg);
end if;
To_Stderr (Nline);
-- Traceback exists
else
-- Note we can have this whole information output twice if
-- this occurrence gets reraised up to here.
To_Stderr (Nline);
To_Stderr ("Execution terminated by unhandled exception");
To_Stderr (Nline);
To_Stderr (Exc_Info (1 .. Exc_Info_Last));
end if;
Unhandled_Terminate;
end Ada.Exceptions.Last_Chance_Handler;
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