/*      $OpenBSD: stringlist.c,v 1.4 2023/01/04 13:00:11 jsg Exp $      */

/*
 * Copyright (c) 1994 Christos Zoulas
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/types.h>
#include <stdio.h>
#include <netgroup.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include "stringlist.h"

static const char _ngstar[] = "*";

static int              getstring(char **, int, char **);
static struct netgroup  *getnetgroup(char **);

/*
 * _ng_sl_init(): Initialize a string list
 */
struct stringlist *
_ng_sl_init(void)
{
        struct stringlist *sl = malloc(sizeof(struct stringlist));
        if (sl == NULL)
                return NULL;

        sl->sl_cur = 0;
        sl->sl_max = 20;
        sl->sl_str = calloc(sl->sl_max, sizeof(char *));
        if (sl->sl_str == NULL) {
                free(sl);
                return NULL;
        }
        return sl;
}


/*
 * _ng_sl_add(): Add an item to the string list
 */
int
_ng_sl_add(struct stringlist *sl, char *name)
{
        if (sl->sl_cur == sl->sl_max - 1) {
                char **slstr;

                sl->sl_max += 20;
                slstr = reallocarray(sl->sl_str, sl->sl_max, sizeof(char *));
                if (slstr == NULL) {
                        free(sl->sl_str);
                        sl->sl_str = NULL;
                        return -1;
                }
                sl->sl_str = slstr;
        }
        sl->sl_str[sl->sl_cur++] = name;
        return 0;
}


/*
 * _ng_sl_free(): Free a stringlist
 */
void
_ng_sl_free(struct stringlist *sl, int all)
{
        size_t  i;

        if (all)
                for (i = 0; i < sl->sl_cur; i++)
                        free(sl->sl_str[i]);
        free(sl->sl_str);
        free(sl);
}


/*
 * sl_find(): Find a name in the string list
 */
char *
_ng_sl_find(struct stringlist *sl, char *name)
{
        size_t  i;

        for (i = 0; i < sl->sl_cur; i++)
                if (strcmp(sl->sl_str[i], name) == 0)
                        return sl->sl_str[i];

        return NULL;
}

/*
 * _ng_parse(): Parse a line and return: _NG_ERROR: Syntax Error _NG_NONE:
 * line was empty or a comment _NG_GROUP: line had a netgroup definition,
 * returned in ng _NG_NAME:  line had a netgroup name, returned in name
 *
 * Public since used by netgroup_mkdb
 */
int
_ng_parse(char **p, char **name, struct netgroup **ng)
{
        while (**p) {
                if (**p == '#')
                        /* comment */
                        return _NG_NONE;

                while (**p && _NG_ISSPACE(**p))
                        /* skipblank */
                        (*p)++;

                if (**p == '(') {
                        if ((*ng = getnetgroup(p)) == NULL)
                                return _NG_ERROR;
                        return _NG_GROUP;
                } else {
                        char    *np;
                        int     i;

                        for (np = *p; **p && !_NG_ISSPACE(**p); (*p)++)
                                continue;
                        if (np != *p) {
                                i = (*p - np) + 1;
                                *name = malloc(i);
                                if (*name == NULL)
                                        return _NG_ERROR;
                                memcpy(*name, np, i);
                                (*name)[i - 1] = '\0';
                                return _NG_NAME;
                        }
                }
        }
        return _NG_NONE;
}

/*
 * _ng_makekey(): Make a key from the two names given. The key is of the form
 * <name1>.<name2> Names strings are replaced with * if they are empty;
 */
char *
_ng_makekey(const char *s1, const char *s2, size_t len)
{
        char *buf = malloc(len);
        int ret;

        if (buf == NULL)
                return NULL;
        ret = snprintf(buf, len, "%s.%s", _NG_STAR(s1), _NG_STAR(s2));
        if (ret < 0 || ret >= len) {
                free(buf);
                return NULL;
        }

        return buf;
}

void
_ng_print(char *buf, size_t len, const struct netgroup *ng)
{
        (void) snprintf(buf, len, "(%s,%s,%s)", _NG_EMPTY(ng->ng_host),
            _NG_EMPTY(ng->ng_user), _NG_EMPTY(ng->ng_domain));
}

/*
 * getnetgroup(): Parse a netgroup, and advance the pointer
 */
static struct netgroup *
getnetgroup(char **pp)
{
        struct netgroup *ng = malloc(sizeof(struct netgroup));

        if (ng == NULL)
                return NULL;

        (*pp)++;        /* skip '(' */
        if (!getstring(pp, ',', &ng->ng_host))
                goto badhost;

        if (!getstring(pp, ',', &ng->ng_user))
                goto baduser;

        if (!getstring(pp, ')', &ng->ng_domain))
                goto baddomain;

#ifdef DEBUG_NG
        {
                char buf[1024];
                _ng_print(buf, sizeof(buf), ng);
                fprintf(stderr, "netgroup %s\n", buf);
        }
#endif
        return ng;

baddomain:
        free(ng->ng_user);
baduser:
        free(ng->ng_host);
badhost:
        free(ng);
        return NULL;
}

/*
 * getstring(): Get a string delimited by the character, skipping leading and
 * trailing blanks and advancing the pointer
 */
static int
getstring(char **pp, int del, char **str)
{
        char *sp, *ep, *dp;

        /* skip leading blanks */
        for (sp = *pp; *sp && _NG_ISSPACE(*sp); sp++)
                continue;

        /* accumulate till delimiter or space */
        for (ep = sp; *ep && *ep != del && !_NG_ISSPACE(*ep); ep++)
                continue;

        /* hunt for the delimiter */
        for (dp = ep; *dp && *dp != del && _NG_ISSPACE(*dp); dp++)
                continue;

        if (*dp != del) {
                *str = NULL;
                return 0;
        }

        *pp = ++dp;

        del = (ep - sp) + 1;
        if (del > 1) {
                dp = malloc(del);
                if (dp == NULL)
                        return 0;
                memcpy(dp, sp, del);
                dp[del - 1] = '\0';
        } else
                dp = NULL;

        *str = dp;
        return 1;
}