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/* Hash tables.
Copyright (C) 2000-2021 Free Software Foundation, Inc.
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
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
<>. */
#include "obstack.h"
#ifndef GTY
#define GTY(x) /* nothing */
/* This is what each hash table entry points to. It may be embedded
deeply within another object. */
typedef struct ht_identifier ht_identifier;
typedef struct ht_identifier *ht_identifier_ptr;
struct GTY(()) ht_identifier {
const unsigned char *str;
unsigned int len;
unsigned int hash_value;
#define HT_LEN(NODE) ((NODE)->len)
#define HT_STR(NODE) ((NODE)->str)
typedef struct ht cpp_hash_table;
typedef struct ht_identifier *hashnode;
enum ht_lookup_option {HT_NO_INSERT = 0, HT_ALLOC};
/* An identifier hash table for cpplib and the front ends. */
struct ht
/* Identifiers are allocated from here. */
struct obstack stack;
hashnode *entries;
/* Call back, allocate a node. */
hashnode (*alloc_node) (cpp_hash_table *);
/* Call back, allocate something that hangs off a node like a cpp_macro.
NULL means use the usual allocator. */
void * (*alloc_subobject) (size_t);
unsigned int nslots; /* Total slots in the entries array. */
unsigned int nelements; /* Number of live elements. */
/* Link to reader, if any. For the benefit of cpplib. */
struct cpp_reader *pfile;
/* Table usage statistics. */
unsigned int searches;
unsigned int collisions;
/* Should 'entries' be freed when it is no longer needed? */
bool entries_owned;
/* Initialize the hashtable with 2 ^ order entries. */
extern cpp_hash_table *ht_create (unsigned int order);
/* Frees all memory associated with a hash table. */
extern void ht_destroy (cpp_hash_table *);
extern hashnode ht_lookup (cpp_hash_table *, const unsigned char *,
size_t, enum ht_lookup_option);
extern hashnode ht_lookup_with_hash (cpp_hash_table *, const unsigned char *,
size_t, unsigned int,
enum ht_lookup_option);
#define HT_HASHSTEP(r, c) ((r) * 67 + ((c) - 113));
#define HT_HASHFINISH(r, len) ((r) + (len))
/* For all nodes in TABLE, make a callback. The callback takes
TABLE->PFILE, the node, and a PTR, and the callback sequence stops
if the callback returns zero. */
typedef int (*ht_cb) (struct cpp_reader *, hashnode, const void *);
extern void ht_forall (cpp_hash_table *, ht_cb, const void *);
/* For all nodes in TABLE, call the callback. If the callback returns
a nonzero value, the node is removed from the table. */
extern void ht_purge (cpp_hash_table *, ht_cb, const void *);
/* Restore the hash table. */
extern void ht_load (cpp_hash_table *ht, hashnode *entries,
unsigned int nslots, unsigned int nelements, bool own);
/* Dump allocation statistics to stderr. */
extern void ht_dump_statistics (cpp_hash_table *);
#endif /* LIBCPP_SYMTAB_H */