+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNAT RUN-TIME COMPONENTS --
--- --
--- A D A . E X C E P T I O N S --
--- --
--- S p e c --
--- --
--- $Revision: 1.1.16.1 $
--- --
--- Copyright (C) 1992-2001 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. --
--- --
-------------------------------------------------------------------------------
-
-pragma Polling (Off);
--- We must turn polling off for this unit, because otherwise we get
--- elaboration circularities with ourself.
-
-with System;
-with System.Standard_Library;
-
-package Ada.Exceptions is
-
- type Exception_Id is private;
- Null_Id : constant Exception_Id;
-
- type Exception_Occurrence is limited private;
- type Exception_Occurrence_Access is access all Exception_Occurrence;
-
- Null_Occurrence : constant Exception_Occurrence;
-
- function Exception_Name (X : Exception_Occurrence) return String;
- -- Same as Exception_Name (Exception_Identity (X))
-
- function Exception_Name (Id : Exception_Id) return String;
-
- procedure Raise_Exception (E : Exception_Id; Message : String := "");
- -- Note: it would be really nice to give a pragma No_Return for this
- -- procedure, but it would be wrong, since Raise_Exception does return
- -- if given the null exception. However we do special case the name in
- -- the test in the compiler for issuing a warning for a missing return
- -- after this call. Program_Error seems reasonable enough in such a case.
- -- See also the routine Raise_Exception_Always in the private part.
-
- function Exception_Message (X : Exception_Occurrence) return String;
-
- procedure Reraise_Occurrence (X : Exception_Occurrence);
- -- Note: it would be really nice to give a pragma No_Return for this
- -- procedure, but it would be wrong, since Reraise_Occurrence does return
- -- if the argument is the null exception occurrence. See also procedure
- -- Reraise_Occurrence_Always in the private part of this package.
-
- function Exception_Identity (X : Exception_Occurrence) return Exception_Id;
-
- function Exception_Information (X : Exception_Occurrence) return String;
- -- The format of the exception information is as follows:
- --
- -- exception name (as in Exception_Name)
- -- message (or a null line if no message)
- -- PID=nnnn
- -- 0xyyyyyyyy 0xyyyyyyyy ...
- --
- -- The lines are separated by an ASCII.CR/ASCII.LF sequence.
- -- The nnnn is the partition Id given as decimal digits.
- -- The 0x... line represents traceback program counter locations,
- -- in order with the first one being the exception location.
-
- -- Note on ordering: the compiler uses the Save_Occurrence procedure, but
- -- not the function from Rtsfind, so it is important that the procedure
- -- come first, since Rtsfind finds the first matching entity.
-
- procedure Save_Occurrence
- (Target : out Exception_Occurrence;
- Source : Exception_Occurrence);
-
- function Save_Occurrence
- (Source : Exception_Occurrence)
- return Exception_Occurrence_Access;
-
-private
- package SSL renames System.Standard_Library;
-
- subtype EOA is Exception_Occurrence_Access;
-
- Exception_Msg_Max_Length : constant := 200;
-
- ------------------
- -- Exception_Id --
- ------------------
-
- subtype Code_Loc is System.Address;
- -- Code location used in building exception tables and for call
- -- addresses when propagating an exception (also traceback table)
- -- Values of this type are created by using Label'Address or
- -- extracted from machine states using Get_Code_Loc.
-
- Null_Loc : constant Code_Loc := System.Null_Address;
- -- Null code location, used to flag outer level frame
-
- type Exception_Id is new SSL.Exception_Data_Ptr;
-
- function EId_To_String (X : Exception_Id) return String;
- function String_To_EId (S : String) return Exception_Id;
- pragma Stream_Convert (Exception_Id, String_To_EId, EId_To_String);
- -- Functions for implementing Exception_Id stream attributes
-
- Null_Id : constant Exception_Id := null;
-
- -------------------------
- -- Private Subprograms --
- -------------------------
-
- function Current_Target_Exception return Exception_Occurrence;
- pragma Export
- (Ada, Current_Target_Exception,
- "__gnat_current_target_exception");
- -- This routine should return the current raised exception on targets
- -- which have built-in exception handling such as the Java Virtual
- -- Machine. For other targets this routine is simply ignored. Currently,
- -- only JGNAT uses this. See 4jexcept.ads for details. The pragma Export
- -- allows this routine to be accessed elsewhere in the run-time, even
- -- though it is in the private part of this package (it is not allowed
- -- to be in the visible part, since this is set by the reference manual).
-
- function Exception_Name_Simple (X : Exception_Occurrence) return String;
- -- Like Exception_Name, but returns the simple non-qualified name of
- -- the exception. This is used to implement the Exception_Name function
- -- in Current_Exceptions (the DEC compatible unit). It is called from
- -- the compiler generated code (using Rtsfind, which does not respect
- -- the private barrier, so we can place this function in the private
- -- part where the compiler can find it, but the spec is unchanged.)
-
- procedure Raise_Exception_Always (E : Exception_Id; Message : String := "");
- pragma No_Return (Raise_Exception_Always);
- pragma Export (Ada, Raise_Exception_Always, "__gnat_raise_exception");
- -- This differs from Raise_Exception only in that the caller has determined
- -- that for sure the parameter E is not null, and that therefore the call
- -- to this procedure cannot return. The expander converts Raise_Exception
- -- calls to Raise_Exception_Always if it can determine this is the case.
- -- The Export allows this routine to be accessed from Pure units.
-
- procedure Raise_No_Msg (E : Exception_Id);
- pragma No_Return (Raise_No_Msg);
- -- Raises an exception with no message with given exception id value.
- -- Abort is deferred before the raise call.
-
- procedure Raise_From_Signal_Handler
- (E : Exception_Id;
- M : SSL.Big_String_Ptr);
- pragma Export
- (Ada, Raise_From_Signal_Handler,
- "ada__exceptions__raise_from_signal_handler");
- pragma No_Return (Raise_From_Signal_Handler);
- -- This routine is used to raise an exception from a signal handler.
- -- The signal handler has already stored the machine state (i.e. the
- -- state that corresponds to the location at which the signal was
- -- raised). E is the Exception_Id specifying what exception is being
- -- raised, and M is a pointer to a null-terminated string which is the
- -- message to be raised. Note that this routine never returns, so it is
- -- permissible to simply jump to this routine, rather than call it. This
- -- may be appropriate for systems where the right way to get out of a
- -- signal handler is to alter the PC value in the machine state or in
- -- some other way ask the operating system to return here rather than
- -- to the original location.
-
- procedure Raise_With_C_Msg
- (E : Exception_Id;
- M : SSL.Big_String_Ptr);
- pragma Export (Ada, Raise_With_C_Msg, "ada__exceptions__raise_with_c_msg");
- pragma No_Return (Raise_With_C_Msg);
- -- Raises an exception with with given exception id value and message.
- -- M is a null terminated string with the message to be raised. Abort
- -- is deferred before the raise call.
-
- procedure Reraise_Occurrence_Always (X : Exception_Occurrence);
- pragma No_Return (Reraise_Occurrence_Always);
- -- This differs from Raise_Occurrence only in that the caller guarantees
- -- that for sure the parameter X is not the null occurrence, and that
- -- therefore this procedure cannot return. The expander uses this routine
- -- in the translation of a raise statement with no parameter (reraise).
-
- procedure Reraise_Occurrence_No_Defer (X : Exception_Occurrence);
- pragma No_Return (Reraise_Occurrence_No_Defer);
- -- Exactly like Reraise_Occurrence, except that abort is not deferred
- -- before the call and the parameter X is known not to be the null
- -- occurrence. This is used in generated code when it is known
- -- that abort is already deferred.
-
- procedure SDP_Table_Build
- (SDP_Addresses : System.Address;
- SDP_Count : Natural;
- Elab_Addresses : System.Address;
- Elab_Addr_Count : Natural);
- pragma Export (C, SDP_Table_Build, "__gnat_SDP_Table_Build");
- -- This is the routine that is called to build and sort the list of
- -- subprogram descriptor pointers. In the normal case it is called
- -- once at the start of execution, but it can also be called as part
- -- of the explicit initialization routine (adainit) when there is no
- -- Ada main program. In particular, in the case where multiple Ada
- -- libraries are present, this routine can be called more than once
- -- for each library, in which case it augments the previously set
- -- table with the new entries specified by the parameters.
- --
- -- SDP_Addresses Address of the start of the list of addresses of
- -- __gnat_unit_name__SDP values constructed for each
- -- unit, (see System.Exceptions).
- --
- -- SDP_Count Number of entries in SDP_Addresses
- --
- -- Elab_Addresses Address of the start of a list of addresses of
- -- generated Ada elaboration routines, as well as
- -- one extra entry for the generated main program.
- -- These are used to generate the dummy SDP's that
- -- mark the outer scope.
- --
- -- Elab_Addr_Count Number of entries in Elab_Addresses
-
- procedure Break_Start;
- pragma Export (C, Break_Start, "__gnat_break_start");
- -- This is a dummy procedure that is called at the start of execution.
- -- Its sole purpose is to provide a well defined point for the placement
- -- of a main program breakpoint. We put the routine in Ada.Exceptions so
- -- that the standard mechanism of always stepping up from breakpoints
- -- within Ada.Exceptions leaves us sitting in the main program.
-
- -----------------------
- -- Polling Interface --
- -----------------------
-
- -- The GNAT compiler has an option to generate polling calls to the Poll
- -- routine in this package. Specifying the -gnatP option for a compilation
- -- causes a call to Ada.Exceptions.Poll to be generated on every subprogram
- -- entry and on every iteration of a loop, thus avoiding the possibility of
- -- a case of unbounded time between calls.
-
- -- This polling interface may be used for instrumentation or debugging
- -- purposes (e.g. implementing watchpoints in software or in the debugger).
-
- -- In the GNAT technology itself, this interface is used to implement
- -- immediate aynschronous transfer of control and immediate abort on
- -- targets which do not provide for one thread interrupting another.
-
- -- Note: this used to be in a separate unit called System.Poll, but that
- -- caused horrible circular elaboration problems between System.Poll and
- -- Ada.Exceptions. One way of solving such circularities is unification!
-
- procedure Poll;
- -- Check for asynchronous abort. Note that we do not inline the body.
- -- This makes the interface more useful for debugging purposes.
-
- --------------------------
- -- Exception_Occurrence --
- --------------------------
-
- Max_Tracebacks : constant := 50;
- -- Maximum number of trace backs stored in exception occurrence
-
- type Tracebacks_Array is array (1 .. Max_Tracebacks) of Code_Loc;
- -- Traceback array stored in exception occurrence
-
- type Exception_Occurrence is record
- Id : Exception_Id;
- -- Exception_Identity for this exception occurrence
- -- WARNING System.System.Finalization_Implementation.Finalize_List
- -- relies on the fact that this field is always first in the exception
- -- occurrence
-
- Msg_Length : Natural := 0;
- -- Length of message (zero = no message)
-
- Msg : String (1 .. Exception_Msg_Max_Length);
- -- Characters of message
-
- Cleanup_Flag : Boolean;
- -- The cleanup flag is normally False, it is set True for an exception
- -- occurrence passed to a cleanup routine, and will still be set True
- -- when the cleanup routine does a Reraise_Occurrence call using this
- -- exception occurrence. This is used to avoid recording a bogus trace
- -- back entry from this reraise call.
-
- Exception_Raised : Boolean := False;
- -- Set to true to indicate that this exception occurrence has actually
- -- been raised. When an exception occurrence is first created, this is
- -- set to False, then when it is processed by Raise_Current_Exception,
- -- it is set to True. If Raise_Current_Exception is used to raise an
- -- exception for which this flag is already True, then it knows that
- -- it is dealing with the reraise case (which is useful to distinguish
- -- for exception tracing purposes).
-
- Pid : Natural;
- -- Partition_Id for partition raising exception
-
- Num_Tracebacks : Natural range 0 .. Max_Tracebacks := 0;
- -- Number of traceback entries stored
-
- Tracebacks : Tracebacks_Array;
- -- Stored tracebacks (in Tracebacks (1 .. Num_Tracebacks))
- end record;
-
- function "=" (Left, Right : Exception_Occurrence) return Boolean
- is abstract;
- -- Don't allow comparison on exception occurrences, we should not need
- -- this, and it would not work right, because of the Msg and Tracebacks
- -- fields which have unused entries not copied by Save_Occurrence.
-
- function EO_To_String (X : Exception_Occurrence) return String;
- function String_To_EO (S : String) return Exception_Occurrence;
- pragma Stream_Convert (Exception_Occurrence, String_To_EO, EO_To_String);
- -- Functions for implementing Exception_Occurrence stream attributes
-
- Null_Occurrence : constant Exception_Occurrence := (
- Id => Null_Id,
- Msg_Length => 0,
- Msg => (others => ' '),
- Cleanup_Flag => False,
- Exception_Raised => False,
- Pid => 0,
- Num_Tracebacks => 0,
- Tracebacks => (others => Null_Loc));
-
-end Ada.Exceptions;
projects / msp430-gcc.git / blobdiff