src/lib/str-table.c

/* Copyright (c) 2014-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "hash.h"
#include "str-table.h"

struct str_table {
    HASH_TABLE(char *, void *) hash;
};

struct str_table *str_table_init(void)
{
    struct str_table *table;

    table = i_new(struct str_table, 1);
    hash_table_create(&table->hash, default_pool, 0, str_hash, strcmp);
    return table;
}

void str_table_deinit(struct str_table **_table)
{
    struct str_table *table = *_table;
    struct hash_iterate_context *iter;
    char *key;
    void *value;

    *_table = NULL;

    iter = hash_table_iterate_init(table->hash);
    while (hash_table_iterate(iter, table->hash, &key, &value))
        i_free(key);
    hash_table_iterate_deinit(&iter);
    hash_table_destroy(&table->hash);
    i_free(table);
}

bool str_table_is_empty(struct str_table *table)
{
    return hash_table_count(table->hash) == 0;
}

const char *str_table_ref(struct str_table *table, const char *str)
{
    char *key;
    void *value;
    unsigned int ref;

    if (!hash_table_lookup_full(table->hash, str, &key, &value)) {
        key = i_strdup(str);
        ref = 1;
    } else {
        ref = POINTER_CAST_TO(value, unsigned int);
        i_assert(ref > 0);
        ref++;
    }
    hash_table_update(table->hash, key, POINTER_CAST(ref));
    return key;
}

void str_table_unref(struct str_table *table, const char **str)
{
    char *key;
    void *value;
    unsigned int ref;

    if (!hash_table_lookup_full(table->hash, *str, &key, &value))
        i_unreached();

    ref = POINTER_CAST_TO(value, unsigned int);
    i_assert(ref > 0);
    if (--ref > 0)
        hash_table_update(table->hash, key, POINTER_CAST(ref));
    else {
        hash_table_remove(table->hash, key);
        i_free(key);
    }
    *str = NULL;
}