gcc/ada/tree_io.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              T R E E _ I O                               --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2008, 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,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, 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 contains the routines used to read and write the tree files
  35 --  used by ASIS. Only the actual read and write routines are here. The open,
  36 --  create and close routines are elsewhere (in Osint in the compiler, and in
  37 --  the tree read driver for the tree read interface).
  38
  39 with Types; use Types;
  40
  41 with System;        use System;
  42 with System.OS_Lib; use System.OS_Lib;
  43
  44 package Tree_IO is
  45
  46    Tree_Format_Error : exception;
  47    --  Raised if a format error is detected in the input file
  48
  49    ASIS_Version_Number : constant := 23;
  50    --  ASIS Version. This is used to check for consistency between the compiler
  51    --  used to generate trees and an ASIS application that is reading the
  52    --  trees. It must be incremented whenever a change is made to the tree
  53    --  format that would result in the compiler being incompatible with an
  54    --  older version of ASIS.
  55
  56    procedure Tree_Read_Initialize (Desc : File_Descriptor);
  57    --  Called to initialize reading of a tree file. This call must be made
  58    --  before calls to Tree_Read_xx. No calls to Tree_Write_xx are permitted
  59    --  after this call.
  60
  61    procedure Tree_Read_Data (Addr : Address; Length : Int);
  62    --  Checks that the Length provided is the same as what has been provided
  63    --  to the corresponding Tree_Write_Data from the current tree file,
  64    --  Tree_Format_Error is raised if it is not the case. If Length is
  65    --  correct and non zero, reads Length bytes of information into memory
  66    --  starting at Addr from the current tree file.
  67
  68    procedure Tree_Read_Bool (B : out Boolean);
  69    --  Reads a single boolean value. The boolean value must have been written
  70    --  with a call to the Tree_Write_Bool procedure.
  71
  72    procedure Tree_Read_Char (C : out Character);
  73    --  Reads a single character. The character must have been written with a
  74    --  call to the Tree_Write_Char procedure.
  75
  76    procedure Tree_Read_Int (N : out Int);
  77    --  Reads a single integer value. The integer must have been written with
  78    --  a call to the Tree_Write_Int procedure.
  79
  80    procedure Tree_Read_Str (S : out String_Ptr);
  81    --  Read string, allocate on heap, and return pointer to allocated string
  82    --  which always has a lower bound of 1.
  83
  84    procedure Tree_Read_Terminate;
  85    --  Called after reading all data, checks that the buffer pointers is at
  86    --  the end of file, raising Tree_Format_Error if not.
  87
  88    procedure Tree_Write_Initialize (Desc : File_Descriptor);
  89    --  Called to initialize writing of a tree file. This call must be made
  90    --  before calls to Tree_Write_xx. No calls to Tree_Read_xx are permitted
  91    --  after this call.
  92
  93    procedure Tree_Write_Data (Addr : Address; Length : Int);
  94    --  Writes Length then, if Length is not null, Length bytes of data
  95    --  starting at Addr to current tree file
  96
  97    procedure Tree_Write_Bool (B : Boolean);
  98    --  Writes a single boolean value to the current tree file
  99
 100    procedure Tree_Write_Char (C : Character);
 101    --  Writes a single character to the current tree file
 102
 103    procedure Tree_Write_Int (N : Int);
 104    --  Writes a single integer value to the current tree file
 105
 106    procedure Tree_Write_Str (S : String_Ptr);
 107    --  Write out string value referenced by S (low bound of S must be 1)
 108
 109    procedure Tree_Write_Terminate;
 110    --  Terminates writing of the file (flushing the buffer), but does not
 111    --  close the file (the caller is responsible for closing the file).
 112
 113 end Tree_IO;