Subversion Repositories openrisc_2011-10-31

/* Hash tables for the CPP library.

   Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1998,

   1999, 2000, 2001, 2002, 2007, 2009 Free Software Foundation, Inc.

   Written by Per Bothner, 1994.

   Based on CCCP program by Paul Rubin, June 1986

   Adapted to ANSI C, Richard Stallman, Jan 1987

This program is free software; you can redistribute it and/or modify it

under the terms of the GNU General Public License as published by the

Free Software Foundation; either version 3, or (at your option) any

later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program; see the file COPYING3.  If not see

<http://www.gnu.org/licenses/>.

 In other words, you are welcome to use, share and improve this program.

 You are forbidden to forbid anyone else to use, share and improve

 what you give them.   Help stamp out software-hoarding!  */

#include "config.h"

#include "system.h"

#include "cpplib.h"

#include "internal.h"

static hashnode alloc_node (hash_table *);

/* Return an identifier node for hashtable.c.  Used by cpplib except

   when integrated with the C front ends.  */

static hashnode

alloc_node (hash_table *table)

{

  cpp_hashnode *node;

  node = XOBNEW (&table->pfile->hash_ob, cpp_hashnode);

  memset (node, 0, sizeof (cpp_hashnode));

  return HT_NODE (node);

}

/* Set up the identifier hash table.  Use TABLE if non-null, otherwise

   create our own.  */

void

_cpp_init_hashtable (cpp_reader *pfile, hash_table *table)

{

  struct spec_nodes *s;

  if (table == NULL)

    {

      pfile->our_hashtable = 1;

      table = ht_create (13);   /* 8K (=2^13) entries.  */

      table->alloc_node = alloc_node;

      _obstack_begin (&pfile->hash_ob, 0, 0,

                      (void *(*) (long)) xmalloc,

                      (void (*) (void *)) free);

    }

  table->pfile = pfile;

  pfile->hash_table = table;

  /* Now we can initialize things that use the hash table.  */

  _cpp_init_directives (pfile);

  _cpp_init_internal_pragmas (pfile);

  s = &pfile->spec_nodes;

  s->n_defined          = cpp_lookup (pfile, DSC("defined"));

  s->n_true             = cpp_lookup (pfile, DSC("true"));

  s->n_false            = cpp_lookup (pfile, DSC("false"));

  s->n__VA_ARGS__       = cpp_lookup (pfile, DSC("__VA_ARGS__"));

  s->n__VA_ARGS__->flags |= NODE_DIAGNOSTIC;

}

/* Tear down the identifier hash table.  */

void

_cpp_destroy_hashtable (cpp_reader *pfile)

{

  if (pfile->our_hashtable)

    {

      ht_destroy (pfile->hash_table);

      obstack_free (&pfile->hash_ob, 0);

    }

}

/* Returns the hash entry for the STR of length LEN, creating one

   if necessary.  */

cpp_hashnode *

cpp_lookup (cpp_reader *pfile, const unsigned char *str, unsigned int len)

{

  /* ht_lookup cannot return NULL.  */

  return CPP_HASHNODE (ht_lookup (pfile->hash_table, str, len, HT_ALLOC));

}

/* Determine whether the str STR, of length LEN, is a defined macro.  */

int

cpp_defined (cpp_reader *pfile, const unsigned char *str, int len)

{

  cpp_hashnode *node;

  node = CPP_HASHNODE (ht_lookup (pfile->hash_table, str, len, HT_NO_INSERT));

  /* If it's of type NT_MACRO, it cannot be poisoned.  */

  return node && node->type == NT_MACRO;

}

/* We don't need a proxy since the hash table's identifier comes first

   in cpp_hashnode.  However, in case this is ever changed, we have a

   static assertion for it.  */

extern char proxy_assertion_broken[offsetof (struct cpp_hashnode, ident) == 0 ? 1 : -1];

/* For all nodes in the hashtable, callback CB with parameters PFILE,

   the node, and V.  */

void

cpp_forall_identifiers (cpp_reader *pfile, cpp_cb cb, void *v)

{

  ht_forall (pfile->hash_table, (ht_cb) cb, v);

}