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#ifndef WP_STRINGHASH_H_
#define WP_STRINGHASH_H_
// whistlepig string map
// (c) 2011 William Morgan. See COPYING for license terms.
//
// based on a heavily modified khash.h
//
// a stringmap is a bidirectional map from strings to int values. like termhash
// and stringpool, it uses a slightly funny API that never allocates memory,
// but instead operates on pointers to preallocated blocks of memory.
//
// uses a stringpool internally to do the int->string mapping. you shouldn't
// have to interact with the stringpool directly; you can just use this object.
//
// like termhash and pool, has a slightly funny API that is designed to work on
// a pre-allocated chunk of memory rather than allocate any of its own.
#include <stdint.h>
#include "stringpool.h"
#include "error.h"
/* list of primes from khash.h:
0ul, 3ul, 11ul, 23ul, 53ul,
97ul, 193ul, 389ul, 769ul, 1543ul,
3079ul, 6151ul, 12289ul, 24593ul, 49157ul,
98317ul, 196613ul, 393241ul, 786433ul, 1572869ul,
3145739ul, 6291469ul, 12582917ul, 25165843ul, 50331653ul,
100663319ul, 201326611ul, 402653189ul, 805306457ul, 1610612741ul,
3221225473ul, 4294967291ul
*/
#define INITIAL_N_BUCKETS_IDX 1
typedef struct stringmap {
uint8_t n_buckets_idx;
uint32_t n_buckets, size, n_occupied, upper_bound;
uint8_t boundary[];
// in memory at this point
// ((n_buckets >> 4) + 1) uint32_t's for the flags
// n_buckets uint32_t's for the keys
} stringmap;
// API methods
// public: write a new stringmap to memory
void stringmap_init(stringmap* h);
// public: add a string. sets id to its id. dupes are fine; will just set the
// id correctly.
wp_error* stringmap_add(stringmap *h, stringpool* p, const char* s, uint32_t* id) RAISES_ERROR;
// public: get the int value given a string. returns (uint32_t)-1 if not found.
uint32_t stringmap_string_to_int(stringmap* h, stringpool* pool, const char* s);
// public: get the string value given an int. returns corrupt data if the int
// is invalid.
const char* stringmap_int_to_string(stringmap* h, stringpool* p, uint32_t i);
// public: returns the byte size of the stringmap
uint32_t stringmap_size(stringmap* h);
// public: returns the initial byte size for an empty stringmap
uint32_t stringmap_initial_size();
// public: returns the byte size for the next larger version of a stringmap
uint32_t stringmap_next_size(stringmap* h);
// public: does the stringmap need a size increase?
int stringmap_needs_bump(stringmap* h);
// public: increases the size of the stringmap
wp_error* stringmap_bump_size(stringmap *h, stringpool* pool) RAISES_ERROR;
#endif
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