/*      $OpenBSD: dict.c,v 1.8 2021/06/14 17:58:15 eric Exp $   */

/*
 * Copyright (c) 2012 Gilles Chehade <gilles@poolp.org>
 * Copyright (c) 2012 Eric Faurot <eric@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/tree.h>

#include <stdlib.h>
#include <string.h>

#include "dict.h"
#include "log.h"

struct dictentry {
        SPLAY_ENTRY(dictentry)  entry;
        const char             *key;
        void                   *data;
};

static int dictentry_cmp(struct dictentry *, struct dictentry *);

SPLAY_PROTOTYPE(_dict, dictentry, entry, dictentry_cmp);

int
dict_check(struct dict *d, const char *k)
{
        struct dictentry        key;

        key.key = k;
        return (SPLAY_FIND(_dict, &d->dict, &key) != NULL);
}

static inline struct dictentry *
dict_alloc(const char *k, void *data)
{
        struct dictentry        *e;
        size_t                   s = strlen(k) + 1;
        void                    *t;

        if ((e = malloc(sizeof(*e) + s)) == NULL)
                return NULL;

        e->key = t = (char*)(e) + sizeof(*e);
        e->data = data;
        memmove(t, k, s);

        return (e);
}

void *
dict_set(struct dict *d, const char *k, void *data)
{
        struct dictentry        *entry, key;
        char                    *old;

        key.key = k;
        if ((entry = SPLAY_FIND(_dict, &d->dict, &key)) == NULL) {
                if ((entry = dict_alloc(k, data)) == NULL)
                        fatal("dict_set: malloc");
                SPLAY_INSERT(_dict, &d->dict, entry);
                old = NULL;
                d->count += 1;
        } else {
                old = entry->data;
                entry->data = data;
        }

        return (old);
}

void
dict_xset(struct dict *d, const char * k, void *data)
{
        struct dictentry        *entry;

        if ((entry = dict_alloc(k, data)) == NULL)
                fatal("dict_xset: malloc");
        if (SPLAY_INSERT(_dict, &d->dict, entry))
                fatalx("dict_xset(%p, %s)", d, k);
        d->count += 1;
}

void *
dict_get(struct dict *d, const char *k)
{
        struct dictentry        key, *entry;

        key.key = k;
        if ((entry = SPLAY_FIND(_dict, &d->dict, &key)) == NULL)
                return (NULL);

        return (entry->data);
}

void *
dict_xget(struct dict *d, const char *k)
{
        struct dictentry        key, *entry;

        key.key = k;
        if ((entry = SPLAY_FIND(_dict, &d->dict, &key)) == NULL)
                fatalx("dict_xget(%p, %s)", d, k);

        return (entry->data);
}

void *
dict_pop(struct dict *d, const char *k)
{
        struct dictentry        key, *entry;
        void                    *data;

        key.key = k;
        if ((entry = SPLAY_FIND(_dict, &d->dict, &key)) == NULL)
                return (NULL);

        data = entry->data;
        SPLAY_REMOVE(_dict, &d->dict, entry);
        free(entry);
        d->count -= 1;

        return (data);
}

void *
dict_xpop(struct dict *d, const char *k)
{
        struct dictentry        key, *entry;
        void                    *data;

        key.key = k;
        if ((entry = SPLAY_FIND(_dict, &d->dict, &key)) == NULL)
                fatalx("dict_xpop(%p, %s)", d, k);

        data = entry->data;
        SPLAY_REMOVE(_dict, &d->dict, entry);
        free(entry);
        d->count -= 1;

        return (data);
}

int
dict_poproot(struct dict *d, void **data)
{
        struct dictentry        *entry;

        entry = SPLAY_ROOT(&d->dict);
        if (entry == NULL)
                return (0);
        if (data)
                *data = entry->data;
        SPLAY_REMOVE(_dict, &d->dict, entry);
        free(entry);
        d->count -= 1;

        return (1);
}

int
dict_root(struct dict *d, const char **k, void **data)
{
        struct dictentry        *entry;

        entry = SPLAY_ROOT(&d->dict);
        if (entry == NULL)
                return (0);
        if (k)
                *k = entry->key;
        if (data)
                *data = entry->data;
        return (1);
}

int
dict_iter(struct dict *d, void **hdl, const char **k, void **data)
{
        struct dictentry *curr = *hdl;

        if (curr == NULL)
                curr = SPLAY_MIN(_dict, &d->dict);
        else
                curr = SPLAY_NEXT(_dict, &d->dict, curr);

        if (curr) {
                *hdl = curr;
                if (k)
                        *k = curr->key;
                if (data)
                        *data = curr->data;
                return (1);
        }

        return (0);
}

int
dict_iterfrom(struct dict *d, void **hdl, const char *kfrom, const char **k,
    void **data)
{
        struct dictentry *curr = *hdl, key;

        if (curr == NULL) {
                if (kfrom == NULL)
                        curr = SPLAY_MIN(_dict, &d->dict);
                else {
                        key.key = kfrom;
                        curr = SPLAY_FIND(_dict, &d->dict, &key);
                        if (curr == NULL) {
                                SPLAY_INSERT(_dict, &d->dict, &key);
                                curr = SPLAY_NEXT(_dict, &d->dict, &key);
                                SPLAY_REMOVE(_dict, &d->dict, &key);
                        }
                }
        } else
                curr = SPLAY_NEXT(_dict, &d->dict, curr);

        if (curr) {
                *hdl = curr;
                if (k)
                        *k = curr->key;
                if (data)
                        *data = curr->data;
                return (1);
        }

        return (0);
}

void
dict_merge(struct dict *dst, struct dict *src)
{
        struct dictentry        *entry;

        while (!SPLAY_EMPTY(&src->dict)) {
                entry = SPLAY_ROOT(&src->dict);
                SPLAY_REMOVE(_dict, &src->dict, entry);
                if (SPLAY_INSERT(_dict, &dst->dict, entry))
                        fatalx("dict_merge: duplicate");
        }
        dst->count += src->count;
        src->count = 0;
}

static int
dictentry_cmp(struct dictentry *a, struct dictentry *b)
{
        return strcmp(a->key, b->key);
}

SPLAY_GENERATE(_dict, dictentry, entry, dictentry_cmp);