gcc/m2/gm2-libs/RTExceptions.def

   1 (* RTExceptions.def runtime exception handler routines.
   2
   3 Copyright (C) 2008-2021 Free Software Foundation, Inc.
   4 Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.
   5
   6 This file is part of GNU Modula-2.
   7
   8 GNU Modula-2 is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GNU Modula-2 is distributed in the hope that it will be useful, but
  14 WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 General Public License for more details.
  17
  18 Under Section 7 of GPL version 3, you are granted additional
  19 permissions described in the GCC Runtime Library Exception, version
  20 3.1, as published by the Free Software Foundation.
  21
  22 You should have received a copy of the GNU General Public License and
  23 a copy of the GCC Runtime Library Exception along with this program;
  24 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  25 <http://www.gnu.org/licenses/>.  *)
  26
  27 DEFINITION MODULE RTExceptions ;
  28
  29 (* Runtime exception handler routines.  This should
  30    be considered as a system module for GNU Modula-2
  31    and allow the compiler to interface with exception
  32    handling.  *)
  33
  34 FROM SYSTEM IMPORT ADDRESS ;
  35 EXPORT QUALIFIED EHBlock,
  36                  Raise, SetExceptionBlock, GetExceptionBlock,
  37                  GetTextBuffer, GetTextBufferSize, GetNumber,
  38                  InitExceptionBlock, KillExceptionBlock,
  39                  PushHandler, PopHandler,
  40                  BaseExceptionsThrow, DefaultErrorCatch,
  41                  IsInExceptionState, SetExceptionState,
  42                  SwitchExceptionState, GetBaseExceptionBlock,
  43                  SetExceptionSource, GetExceptionSource ;
  44
  45 TYPE
  46    EHBlock ;
  47    ProcedureHandler = PROCEDURE ;
  48
  49
  50 (*
  51    Raise - invoke the exception handler associated with, number,
  52            in the active EHBlock.  It keeps a record of the number
  53            and message in the EHBlock for later use.
  54 *)
  55
  56 PROCEDURE Raise (number: CARDINAL;
  57                  file: ADDRESS; line: CARDINAL;
  58                  column: CARDINAL; function: ADDRESS;
  59                  message: ADDRESS) ;
  60
  61
  62 (*
  63    SetExceptionBlock - sets, source, as the active EHB.
  64 *)
  65
  66 PROCEDURE SetExceptionBlock (source: EHBlock) ;
  67
  68
  69 (*
  70    GetExceptionBlock - returns the active EHB.
  71 *)
  72
  73 PROCEDURE GetExceptionBlock () : EHBlock ;
  74
  75
  76 (*
  77    GetTextBuffer - returns the address of the EHB buffer.
  78 *)
  79
  80 PROCEDURE GetTextBuffer (e: EHBlock) : ADDRESS ;
  81
  82
  83 (*
  84    GetTextBufferSize - return the size of the EHB text buffer.
  85 *)
  86
  87 PROCEDURE GetTextBufferSize (e: EHBlock) : CARDINAL ;
  88
  89
  90 (*
  91    GetNumber - return the exception number associated with,
  92                source.
  93 *)
  94
  95 PROCEDURE GetNumber (source: EHBlock) : CARDINAL ;
  96
  97
  98 (*
  99    InitExceptionBlock - creates and returns a new exception block.
 100 *)
 101
 102 PROCEDURE InitExceptionBlock () : EHBlock ;
 103
 104
 105 (*
 106    KillExceptionBlock - destroys the EHB, e, and all its handlers.
 107 *)
 108
 109 PROCEDURE KillExceptionBlock (e: EHBlock) : EHBlock ;
 110
 111
 112 (*
 113    PushHandler - install a handler in EHB, e.
 114 *)
 115
 116 PROCEDURE PushHandler (e: EHBlock; number: CARDINAL; p: ProcedureHandler) ;
 117
 118
 119 (*
 120    PopHandler - removes the handler associated with, number, from
 121                 EHB, e.
 122 *)
 123
 124 PROCEDURE PopHandler (e: EHBlock; number: CARDINAL) ;
 125
 126
 127 (*
 128    DefaultErrorCatch - displays the current error message in
 129                        the current exception block and then
 130                        calls HALT.
 131 *)
 132
 133 PROCEDURE DefaultErrorCatch ;
 134
 135
 136 (*
 137    BaseExceptionsThrow - configures the Modula-2 exceptions to call
 138                          THROW which in turn can be caught by an
 139                          exception block.  If this is not called then
 140                          a Modula-2 exception will simply call an
 141                          error message routine and then HALT.
 142 *)
 143
 144 PROCEDURE BaseExceptionsThrow ;
 145
 146
 147 (*
 148    IsInExceptionState - returns TRUE if the program is currently
 149                         in the exception state.
 150 *)
 151
 152 PROCEDURE IsInExceptionState () : BOOLEAN ;
 153
 154
 155 (*
 156    SetExceptionState - returns the current exception state and
 157                        then sets the current exception state to,
 158                        to.
 159 *)
 160
 161 PROCEDURE SetExceptionState (to: BOOLEAN) : BOOLEAN ;
 162
 163
 164 (*
 165    SwitchExceptionState - assigns, from, with the current exception
 166                           state and then assigns the current exception
 167                           to, to.
 168 *)
 169
 170 PROCEDURE SwitchExceptionState (VAR from: BOOLEAN; to: BOOLEAN) ;
 171
 172
 173 (*
 174    GetBaseExceptionBlock - returns the initial language exception block
 175                            created.
 176 *)
 177
 178 PROCEDURE GetBaseExceptionBlock () : EHBlock ;
 179
 180
 181 (*
 182    SetExceptionSource - sets the current exception source to, source.
 183 *)
 184
 185 PROCEDURE SetExceptionSource (source: ADDRESS) ;
 186
 187
 188 (*
 189    GetExceptionSource - returns the current exception source.
 190 *)
 191
 192 PROCEDURE GetExceptionSource () : ADDRESS ;
 193
 194
 195 END RTExceptions.