alist.c

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/*
 * Portions Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
 * Portions Copyright (C) 2001  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and/or 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 ISC AND NOMINUM DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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.
 *
 * Portions Copyright (C) 2001  Nominum, Inc.
 *
 * Permission to use, copy, modify, and/or 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 ISC AND NOMINUM DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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.
 */

/* $Id: alist.c,v 1.8 2007/08/28 07:20:43 tbox Exp $ */

/*! \file */

#include <config.h>

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

#include <isccc/alist.h>
#include <isc/assertions.h>
#include <isccc/result.h>
#include <isccc/sexpr.h>
#include <isccc/util.h>

#define CAR(s)                  (s)->value.as_dottedpair.car
#define CDR(s)                  (s)->value.as_dottedpair.cdr

#define ALIST_TAG               "*alist*"
#define MAX_INDENT              64

static char spaces[MAX_INDENT + 1] = 
        "                                                                ";

isccc_sexpr_t *
isccc_alist_create(void)
{
        isccc_sexpr_t *alist, *tag;

        tag = isccc_sexpr_fromstring(ALIST_TAG);
        if (tag == NULL)
                return (NULL);
        alist = isccc_sexpr_cons(tag, NULL);
        if (alist == NULL) {
                isccc_sexpr_free(&tag);
                return (NULL);
        }

        return (alist);
}

isc_boolean_t
isccc_alist_alistp(isccc_sexpr_t *alist)
{
        isccc_sexpr_t *car;

        if (alist == NULL || alist->type != ISCCC_SEXPRTYPE_DOTTEDPAIR)
                return (ISC_FALSE);
        car = CAR(alist);
        if (car == NULL || car->type != ISCCC_SEXPRTYPE_STRING)
                return (ISC_FALSE);
        if (strcmp(car->value.as_string, ALIST_TAG) != 0)
                return (ISC_FALSE);
        return (ISC_TRUE);
}

isc_boolean_t
isccc_alist_emptyp(isccc_sexpr_t *alist)
{
        REQUIRE(isccc_alist_alistp(alist));

        if (CDR(alist) == NULL)
                return (ISC_TRUE);
        return (ISC_FALSE);
}

isccc_sexpr_t *
isccc_alist_first(isccc_sexpr_t *alist)
{
        REQUIRE(isccc_alist_alistp(alist));

        return (CDR(alist));
}

isccc_sexpr_t *
isccc_alist_assq(isccc_sexpr_t *alist, const char *key)
{
        isccc_sexpr_t *car, *caar;

        REQUIRE(isccc_alist_alistp(alist));

        /*
         * Skip alist type tag.
         */
        alist = CDR(alist);

        while (alist != NULL) {
                INSIST(alist->type == ISCCC_SEXPRTYPE_DOTTEDPAIR);
                car = CAR(alist);
                INSIST(car->type == ISCCC_SEXPRTYPE_DOTTEDPAIR);
                caar = CAR(car);
                if (caar->type == ISCCC_SEXPRTYPE_STRING &&
                    strcmp(caar->value.as_string, key) == 0)
                        return (car);
                alist = CDR(alist);
        }

        return (NULL);
}

void
isccc_alist_delete(isccc_sexpr_t *alist, const char *key)
{
        isccc_sexpr_t *car, *caar, *rest, *prev;

        REQUIRE(isccc_alist_alistp(alist));

        prev = alist;
        rest = CDR(alist);
        while (rest != NULL) {
                INSIST(rest->type == ISCCC_SEXPRTYPE_DOTTEDPAIR);
                car = CAR(rest);
                INSIST(car != NULL && car->type == ISCCC_SEXPRTYPE_DOTTEDPAIR);
                caar = CAR(car);
                if (caar->type == ISCCC_SEXPRTYPE_STRING &&
                    strcmp(caar->value.as_string, key) == 0) {
                        CDR(prev) = CDR(rest);
                        CDR(rest) = NULL;
                        isccc_sexpr_free(&rest);
                        break;
                }
                prev = rest;
                rest = CDR(rest);
        }
}

isccc_sexpr_t *
isccc_alist_define(isccc_sexpr_t *alist, const char *key, isccc_sexpr_t *value)
{
        isccc_sexpr_t *kv, *k, *elt;

        kv = isccc_alist_assq(alist, key);
        if (kv == NULL) {
                /*
                 * New association.
                 */
                k = isccc_sexpr_fromstring(key);
                if (k == NULL)
                        return (NULL);
                kv = isccc_sexpr_cons(k, value);
                if (kv == NULL) {
                        isccc_sexpr_free(&kv);
                        return (NULL);
                }
                elt = isccc_sexpr_addtolist(&alist, kv);
                if (elt == NULL) {
                        isccc_sexpr_free(&kv);
                        return (NULL);
                }
        } else {
                /*
                 * We've already got an entry for this key.  Replace it.
                 */
                isccc_sexpr_free(&CDR(kv));
                CDR(kv) = value;
        }

        return (kv);
}

isccc_sexpr_t *
isccc_alist_definestring(isccc_sexpr_t *alist, const char *key, const char *str)
{
        isccc_sexpr_t *v, *kv;

        v = isccc_sexpr_fromstring(str);
        if (v == NULL)
                return (NULL);
        kv = isccc_alist_define(alist, key, v);
        if (kv == NULL)
                isccc_sexpr_free(&v);

        return (kv);
}

isccc_sexpr_t *
isccc_alist_definebinary(isccc_sexpr_t *alist, const char *key, isccc_region_t *r)
{
        isccc_sexpr_t *v, *kv;

        v = isccc_sexpr_frombinary(r);
        if (v == NULL)
                return (NULL);
        kv = isccc_alist_define(alist, key, v);
        if (kv == NULL)
                isccc_sexpr_free(&v);

        return (kv);
}

isccc_sexpr_t *
isccc_alist_lookup(isccc_sexpr_t *alist, const char *key)
{
        isccc_sexpr_t *kv;

        kv = isccc_alist_assq(alist, key);
        if (kv != NULL)
                return (CDR(kv));
        return (NULL);
}

isc_result_t
isccc_alist_lookupstring(isccc_sexpr_t *alist, const char *key, char **strp)
{
        isccc_sexpr_t *kv, *v;

        kv = isccc_alist_assq(alist, key);
        if (kv != NULL) {
                v = CDR(kv);
                if (isccc_sexpr_stringp(v)) {
                        if (strp != NULL)
                                *strp = isccc_sexpr_tostring(v);
                        return (ISC_R_SUCCESS);
                } else
                        return (ISC_R_EXISTS);
        }

        return (ISC_R_NOTFOUND);
}

isc_result_t
isccc_alist_lookupbinary(isccc_sexpr_t *alist, const char *key, isccc_region_t **r)
{
        isccc_sexpr_t *kv, *v;

        kv = isccc_alist_assq(alist, key);
        if (kv != NULL) {
                v = CDR(kv);
                if (isccc_sexpr_binaryp(v)) {
                        if (r != NULL)
                                *r = isccc_sexpr_tobinary(v);
                        return (ISC_R_SUCCESS);
                } else
                        return (ISC_R_EXISTS);
        }

        return (ISC_R_NOTFOUND);
}

void
isccc_alist_prettyprint(isccc_sexpr_t *sexpr, unsigned int indent, FILE *stream)
{
        isccc_sexpr_t *elt, *kv, *k, *v;

        if (isccc_alist_alistp(sexpr)) {
                fprintf(stream, "{\n");
                indent += 4;
                for (elt = isccc_alist_first(sexpr);
                     elt != NULL;
                     elt = CDR(elt)) {
                        kv = CAR(elt);
                        INSIST(isccc_sexpr_listp(kv));
                        k = CAR(kv);
                        v = CDR(kv);
                        INSIST(isccc_sexpr_stringp(k));
                        fprintf(stream, "%.*s%s => ", (int)indent, spaces,
                                isccc_sexpr_tostring(k));
                        isccc_alist_prettyprint(v, indent, stream);
                        if (CDR(elt) != NULL)
                                fprintf(stream, ",");
                        fprintf(stream, "\n");
                }
                indent -= 4;
                fprintf(stream, "%.*s}", (int)indent, spaces);
        } else if (isccc_sexpr_listp(sexpr)) {
                fprintf(stream, "(\n");
                indent += 4;
                for (elt = sexpr;
                     elt != NULL;
                     elt = CDR(elt)) {
                        fprintf(stream, "%.*s", (int)indent, spaces);
                        isccc_alist_prettyprint(CAR(elt), indent, stream);
                        if (CDR(elt) != NULL)
                                fprintf(stream, ",");
                        fprintf(stream, "\n");
                }
                indent -= 4;
                fprintf(stream, "%.*s)", (int)indent, spaces);
        } else
                isccc_sexpr_print(sexpr, stream);
}

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