gcc/ada/stringt.h

   1 /****************************************************************************
   2  *                                                                          *
   3  *                         GNAT COMPILER COMPONENTS                         *
   4  *                                                                          *
   5  *                              S T R I N G T                               *
   6  *                                                                          *
   7  *                              C Header File                               *
   8  *                                                                          *
   9  *          Copyright (C) 1992-2003 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,  59 Temple Place - Suite 330,  Boston, *
  20  * MA 02111-1307, USA.                                                      *
  21  *                                                                          *
  22  * GNAT was originally developed  by the GNAT team at  New York University. *
  23  * Extensive contributions were provided by Ada Core Technologies Inc.      *
  24  *                                                                          *
  25  ****************************************************************************/
  26
  27 /* This file is the C file that corresponds to the Ada package spec
  28    Stringt. It was created manually from stringt.ads and stringt.adb
  29
  30    Note: only the access functions are provided, since the tree transformer
  31    is not allowed to modify the tree or its auxiliary structures.
  32
  33    This package contains routines for handling the strings table which is
  34    used to store string constants encountered in the source, and also those
  35    additional string constants generated by compile time concatenation and
  36    other similar processing.
  37
  38    A string constant in this table consists of a series of Char_Code values,
  39    so that 16-bit character codes can be properly handled if this feature is
  40    implemented in the scanner.
  41
  42    There is no guarantee that hashing is used in the implementation. This
  43    means that the caller cannot count on having the same Id value for two
  44    identical strings stored separately.
  45
  46    The String_Id values reference entries in the Strings table, which
  47    contains String_Entry records that record the length of each stored string
  48    and its starting location in the String_Chars table.  */
  49
  50 struct String_Entry
  51 {
  52   Int String_Index;
  53   Int Length;
  54 };
  55
  56 /* Pointer to string entry vector. This pointer is passed to the tree
  57    transformer and stored in a global location.  */
  58 extern struct String_Entry *Strings_Ptr;
  59
  60 /* Pointer to name characters table. This pointer is passed to the tree
  61    transformer and stored in a global location for access from here. The
  62    String_Index values are subscripts into this array.  */
  63 extern Char_Code *String_Chars_Ptr;
  64
  65
  66 /* String_Length returns the length of the specified string.  */
  67 INLINE Int String_Length (String_Id);
  68
  69 INLINE Int
  70 String_Length (String_Id Id)
  71 {
  72   return Strings_Ptr[Id - First_String_Id].Length;
  73 }
  74
  75
  76 /* Get_String_Char obtains the specified character from a stored string.  The
  77    lower bound of stored strings is always 1, so the range of values is 1 to
  78    String_Length (Id).  */
  79 INLINE Char_Code Get_String_Char (String_Id, Int);
  80
  81 INLINE Char_Code
  82 Get_String_Char (String_Id Id, Int Index)
  83 {
  84   return
  85     String_Chars_Ptr
  86       [Strings_Ptr[Id - First_String_Id].String_Index + Index - 1];
  87 }