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) 1992-2018, Free Software Foundation, Inc.       *
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  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- *
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  19  * http://www.gnu.org/licenses for a complete copy of the license.          *
  20  *                                                                          *
  21  * GNAT was originally developed  by the GNAT team at  New York University. *
  22  * Extensive contributions were provided by Ada Core Technologies Inc.      *
  23  *                                                                          *
  24  ****************************************************************************/
  25
  26 /* This file is the C file that corresponds to the Ada package spec
  27    Stringt. It was created manually from stringt.ads and stringt.adb
  28
  29    Note: only the access functions are provided, since the tree transformer
  30    is not allowed to modify the tree or its auxiliary structures.
  31
  32    This package contains routines for handling the strings table which is
  33    used to store string constants encountered in the source, and also those
  34    additional string constants generated by compile time concatenation and
  35    other similar processing.
  36
  37    A string constant in this table consists of a series of Char_Code values,
  38    so that 16-bit character codes can be properly handled if this feature is
  39    implemented in the scanner.
  40
  41    There is no guarantee that hashing is used in the implementation. This
  42    means that the caller cannot count on having the same Id value for two
  43    identical strings stored separately.
  44
  45    The String_Id values reference entries in the Strings table, which
  46    contains String_Entry records that record the length of each stored string
  47    and its starting location in the String_Chars table.  */
  48
  49 struct String_Entry
  50 {
  51   Int String_Index;
  52   Int Length;
  53 };
  54
  55 /* Pointer to string entry vector. This pointer is passed to the tree
  56    transformer and stored in a global location.  */
  57 extern struct String_Entry *Strings_Ptr;
  58
  59 /* Pointer to name characters table. This pointer is passed to the tree
  60    transformer and stored in a global location for access from here. The
  61    String_Index values are subscripts into this array.  */
  62 extern Char_Code *String_Chars_Ptr;
  63
  64
  65 /* String_Length returns the length of the specified string.  */
  66 INLINE Int String_Length (String_Id);
  67
  68 INLINE Int
  69 String_Length (String_Id Id)
  70 {
  71   return Strings_Ptr[Id - First_String_Id].Length;
  72 }
  73
  74
  75 /* Get_String_Char obtains the specified character from a stored string.  The
  76    lower bound of stored strings is always 1, so the range of values is 1 to
  77    String_Length (Id).  */
  78 INLINE Char_Code Get_String_Char (String_Id, Int);
  79
  80 INLINE Char_Code
  81 Get_String_Char (String_Id Id, Int Index)
  82 {
  83   return
  84     String_Chars_Ptr
  85       [Strings_Ptr[Id - First_String_Id].String_Index + Index - 1];
  86 }