root/usr/src/lib/libsocket/inet/getprotoent_r.c
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <ctype.h>
#include <netdb.h>
#include <stdlib.h>
#include <string.h>
#include <nss_dbdefs.h>

int str2protoent(const char *, int, void *,
                char *, int);

static int proto_stayopen;
/*
 * Unsynchronized, but it affects only
 * efficiency, not correctness
 */

static DEFINE_NSS_DB_ROOT(db_root);
static DEFINE_NSS_GETENT(context);

void
_nss_initf_proto(nss_db_params_t *p)
{
        p->name = NSS_DBNAM_PROTOCOLS;
        p->default_config = NSS_DEFCONF_PROTOCOLS;
}

struct protoent *
getprotobyname_r(const char *name, struct protoent *result,
        char *buffer, int buflen)
{
        nss_XbyY_args_t arg;
        nss_status_t    res;

        if (name == (const char *)NULL) {
                errno = ERANGE;
                return (NULL);
        }
        NSS_XbyY_INIT(&arg, result, buffer, buflen, str2protoent);
        arg.key.name    = name;
        arg.stayopen    = proto_stayopen;
        res = nss_search(&db_root, _nss_initf_proto,
                NSS_DBOP_PROTOCOLS_BYNAME, &arg);
        arg.status = res;
        (void) NSS_XbyY_FINI(&arg);
        return ((struct protoent *)arg.returnval);
}

struct protoent *
getprotobynumber_r(int proto, struct protoent *result, char *buffer, int buflen)
{
        nss_XbyY_args_t arg;
        nss_status_t    res;

        NSS_XbyY_INIT(&arg, result, buffer, buflen, str2protoent);
        arg.key.number = proto;
        arg.stayopen    = proto_stayopen;
        res = nss_search(&db_root, _nss_initf_proto,
                NSS_DBOP_PROTOCOLS_BYNUMBER, &arg);
        arg.status = res;
        (void) NSS_XbyY_FINI(&arg);
        return ((struct protoent *)arg.returnval);
}

int
setprotoent(int stay)
{
        proto_stayopen = stay;
        nss_setent(&db_root, _nss_initf_proto, &context);
        return (0);
}

int
endprotoent()
{
        proto_stayopen = 0;
        nss_endent(&db_root, _nss_initf_proto, &context);
        nss_delete(&db_root);
        return (0);
}

struct protoent *
getprotoent_r(struct protoent *result, char *buffer, int buflen)
{
        nss_XbyY_args_t arg;
        nss_status_t    res;

        NSS_XbyY_INIT(&arg, result, buffer, buflen, str2protoent);
        /* No stayopen flag;  of course you stay open for iteration */
        res = nss_getent(&db_root, _nss_initf_proto, &context, &arg);
        arg.status = res;
        (void) NSS_XbyY_FINI(&arg);
        return ((struct protoent *)arg.returnval);
}

/*
 * Return values: 0 = success, 1 = parse error, 2 = erange ...
 * The structure pointer passed in is a structure in the caller's space
 * wherein the field pointers would be set to areas in the buffer if
 * need be. instring and buffer should be separate areas. Let's not
 * fight over crumbs.
 */
int
str2protoent(const char *instr, int lenstr,
        void *ent /* it is really (struct protoent *) */,
        char *buffer, int buflen)
{
        struct  protoent *proto = (struct protoent *)ent;
        const char      *p, *numstart, *namestart, *limit;
        int             numlen, namelen = 0;
        char            numbuf[16];
        char            *numend;

        if ((instr >= buffer && (buffer + buflen) > instr) ||
            (buffer >= instr && (instr + lenstr) > buffer)) {
                return (NSS_STR_PARSE_PARSE);
        }

        p = instr;
        limit = p + lenstr;

        while (p < limit && isspace(*p)) {
                p++;
        }
        namestart = p;
        while (p < limit && !isspace(*p)) {
                p++;            /* Skip over the canonical name */
        }
        namelen = (int)(p - namestart);

        if (buflen <= namelen) { /* not enough buffer */
                return (NSS_STR_PARSE_ERANGE);
        }
        (void) memcpy(buffer, namestart, namelen);
        buffer[namelen] = '\0';
        proto->p_name = buffer;

        while (p < limit && isspace(*p)) {
                p++;
        }
        if (p >= limit) {
                /* Syntax error -- no proto number */
                return (NSS_STR_PARSE_PARSE);
        }
        numstart = p;
        do {
                p++;            /* Find the end of the proto number */
        } while (p < limit && !isspace(*p));
        numlen = (int)(p - numstart);
        if (numlen >= (int)sizeof (numbuf)) {
                /* Syntax error -- supposed number is too long */
                return (NSS_STR_PARSE_PARSE);
        }
        (void) memcpy(numbuf, numstart, (size_t)numlen);
        numbuf[numlen] = '\0';
        proto->p_proto = (int)strtol(numbuf, &numend, 10);
        if (*numend != '\0') {
                /* Syntax error -- protocol number isn't a number */
                return (NSS_STR_PARSE_PARSE);
        }

        while (p < limit && isspace(*p)) {
                p++;
        }
        /*
         * Although nss_files_XY_all calls us with # stripped,
         * we should be able to deal with it here in order to
         * be more useful.
         */
        if (p >= limit || *p == '#') { /* no aliases, no problem */
                char **ptr;

                ptr = (char **)ROUND_UP(buffer + namelen + 1,
                                                        sizeof (char *));
                if ((char *)ptr >= buffer + buflen) {
                        /* hope they don't try to peek in */
                        proto->p_aliases = 0;
                        return (NSS_STR_PARSE_ERANGE);
                } else {
                        *ptr = 0;
                        proto->p_aliases = ptr;
                        return (NSS_STR_PARSE_SUCCESS);
                }
        }
        proto->p_aliases = _nss_netdb_aliases(p, lenstr - (int)(p - instr),
                                buffer + namelen + 1, buflen - namelen - 1);
        return (NSS_STR_PARSE_SUCCESS);
}