gcc/cpphash.h

   1 /* Part of CPP library.  (Macro hash table support.)
   2    Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.
   3
   4 This program is free software; you can redistribute it and/or modify it
   5 under the terms of the GNU General Public License as published by the
   6 Free Software Foundation; either version 2, or (at your option) any
   7 later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 #ifndef __GCC_CPPHASH__
  19 #define __GCC_CPPHASH__
  20
  21 /* Structure allocated for every #define.  For a simple replacement
  22    such as
  23         #define foo bar ,
  24    nargs = -1, the `pattern' list is null, and the expansion is just
  25    the replacement text.  Nargs = 0 means a functionlike macro with no args,
  26    e.g.,
  27        #define getchar() getc (stdin) .
  28    When there are args, the expansion is the replacement text with the
  29    args squashed out, and the reflist is a list describing how to
  30    build the output from the input: e.g., "3 chars, then the 1st arg,
  31    then 9 chars, then the 3rd arg, then 0 chars, then the 2nd arg".
  32    The chars here come from the expansion.  Whatever is left of the
  33    expansion after the last arg-occurrence is copied after that arg.
  34    Note that the reflist can be arbitrarily long---
  35    its length depends on the number of times the arguments appear in
  36    the replacement text, not how many args there are.  Example:
  37    #define f(x) x+x+x+x+x+x+x would have replacement text "++++++" and
  38    pattern list
  39      { (0, 1), (1, 1), (1, 1), ..., (1, 1), NULL }
  40    where (x, y) means (nchars, argno). */
  41
  42 struct reflist
  43 {
  44   struct reflist *next;
  45   char stringify;               /* nonzero if this arg was preceded by a
  46                                    # operator. */
  47   char raw_before;              /* Nonzero if a ## operator before arg. */
  48   char raw_after;               /* Nonzero if a ## operator after arg. */
  49   char rest_args;               /* Nonzero if this arg. absorbs the rest */
  50   int nchars;                   /* Number of literal chars to copy before
  51                                    this arg occurrence.  */
  52   int argno;                    /* Number of arg to substitute (origin-0) */
  53 };
  54
  55 typedef struct definition DEFINITION;
  56 struct definition
  57 {
  58   int nargs;
  59   int length;                   /* length of expansion string */
  60   U_CHAR *expansion;
  61   int line;                     /* Line number of definition */
  62   int col;
  63   const char *file;             /* File of definition */
  64   char rest_args;               /* Nonzero if last arg. absorbs the rest */
  65   struct reflist *pattern;
  66
  67   /* Names of macro args, concatenated in order with commas between
  68      them.  The only use of this is that we warn on redefinition if
  69      this differs between the old and new definitions.  */
  70   U_CHAR *argnames;
  71 };
  72
  73 /* different kinds of things that can appear in the value field
  74    of a hash node. */
  75 union hashval
  76 {
  77   const char *cpval;            /* some predefined macros */
  78   DEFINITION *defn;             /* #define */
  79   struct hashnode *aschain;     /* #assert */
  80 };
  81
  82 typedef struct hashnode HASHNODE;
  83 struct hashnode {
  84   struct hashnode *next;        /* double links for easy deletion */
  85   struct hashnode *prev;
  86   struct hashnode **bucket_hdr; /* also, a back pointer to this node's hash
  87                                    chain is kept, in case the node is the head
  88                                    of the chain and gets deleted. */
  89   enum node_type type;          /* type of special token */
  90   int length;                   /* length of token, for quick comparison */
  91   U_CHAR *name;                 /* the actual name */
  92   union hashval value;          /* pointer to expansion, or whatever */
  93 };
  94
  95 extern HASHNODE *_cpp_install     PARAMS ((cpp_reader *, const U_CHAR *, int,
  96                                            enum node_type, const char *));
  97 extern HASHNODE *_cpp_lookup      PARAMS ((cpp_reader *, const U_CHAR *, int));
  98 extern void _cpp_free_definition  PARAMS ((DEFINITION *));
  99 extern void _cpp_delete_macro     PARAMS ((HASHNODE *));
 100
 101 extern DEFINITION *_cpp_create_definition
 102                                   PARAMS ((cpp_reader *, int));
 103 extern int _cpp_compare_defs              PARAMS ((cpp_reader *, DEFINITION *,
 104                                            DEFINITION *));
 105 extern void _cpp_macroexpand      PARAMS ((cpp_reader *, HASHNODE *));
 106 extern void _cpp_dump_definition  PARAMS ((cpp_reader *, const U_CHAR *, long,
 107                                            DEFINITION *));
 108
 109 #endif