/*
 * GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see
 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 * GPL HEADER END
 */
/*
 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2011, 2012, Intel Corporation.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 * Lustre is a trademark of Sun Microsystems, Inc.
 *
 * libcfs/libcfs/nidstrings.c
 *
 * Author: Phil Schwan <phil@clusterfs.com>
 */

#define DEBUG_SUBSYSTEM S_LNET

#include "../../include/linux/libcfs/libcfs.h"
#include "../../include/linux/lnet/lnet.h"

/* CAVEAT VENDITOR! Keep the canonical string representation of nets/nids
 * consistent in all conversion functions.  Some code fragments are copied
 * around for the sake of clarity...
 */

/* CAVEAT EMPTOR! Racey temporary buffer allocation!
 * Choose the number of nidstrings to support the MAXIMUM expected number of
 * concurrent users.  If there are more, the returned string will be volatile.
 * NB this number must allow for a process to be descheduled for a timeslice
 * between getting its string and using it.
 */

static char      libcfs_nidstrings[LNET_NIDSTR_COUNT][LNET_NIDSTR_SIZE];
static int       libcfs_nidstring_idx;

static spinlock_t libcfs_nidstring_lock;

void libcfs_init_nidstrings(void)
{
        spin_lock_init(&libcfs_nidstring_lock);
}

static char *
libcfs_next_nidstring(void)
{
        char      *str;
        unsigned long  flags;

        spin_lock_irqsave(&libcfs_nidstring_lock, flags);

        str = libcfs_nidstrings[libcfs_nidstring_idx++];
        if (libcfs_nidstring_idx == ARRAY_SIZE(libcfs_nidstrings))
                libcfs_nidstring_idx = 0;

        spin_unlock_irqrestore(&libcfs_nidstring_lock, flags);
        return str;
}

static int libcfs_lo_str2addr(const char *str, int nob, __u32 *addr)
{
        *addr = 0;
        return 1;
}

static void libcfs_ip_addr2str(__u32 addr, char *str)
{
        snprintf(str, LNET_NIDSTR_SIZE, "%u.%u.%u.%u",
                 (addr >> 24) & 0xff, (addr >> 16) & 0xff,
                 (addr >> 8) & 0xff, addr & 0xff);
}

static int libcfs_ip_str2addr(const char *str, int nob, __u32 *addr)
{
        unsigned int    a;
        unsigned int    b;
        unsigned int    c;
        unsigned int    d;
        int             n = nob; /* XscanfX */

        /* numeric IP? */
        if (sscanf(str, "%u.%u.%u.%u%n", &a, &b, &c, &d, &n) >= 4 &&
            n == nob &&
            (a & ~0xff) == 0 && (b & ~0xff) == 0 &&
            (c & ~0xff) == 0 && (d & ~0xff) == 0) {
                *addr = ((a<<24)|(b<<16)|(c<<8)|d);
                return 1;
        }

        return 0;
}

static void libcfs_decnum_addr2str(__u32 addr, char *str)
{
        snprintf(str, LNET_NIDSTR_SIZE, "%u", addr);
}

static void libcfs_hexnum_addr2str(__u32 addr, char *str)
{
        snprintf(str, LNET_NIDSTR_SIZE, "0x%x", addr);
}

static int libcfs_num_str2addr(const char *str, int nob, __u32 *addr)
{
        int     n;

        n = nob;
        if (sscanf(str, "0x%x%n", addr, &n) >= 1 && n == nob)
                return 1;

        n = nob;
        if (sscanf(str, "0X%x%n", addr, &n) >= 1 && n == nob)
                return 1;

        n = nob;
        if (sscanf(str, "%u%n", addr, &n) >= 1 && n == nob)
                return 1;

        return 0;
}

/**
 * Nf_parse_addrlist method for networks using numeric addresses.
 *
 * Examples of such networks are gm and elan.
 *
 * \retval 0 if \a str parsed to numeric address
 * \retval errno otherwise
 */
static int
libcfs_num_parse(char *str, int len, struct list_head *list)
{
        struct cfs_expr_list *el;
        int     rc;

        rc = cfs_expr_list_parse(str, len, 0, MAX_NUMERIC_VALUE, &el);
        if (rc == 0)
                list_add_tail(&el->el_link, list);

        return rc;
}

/*
 * Nf_match_addr method for networks using numeric addresses
 *
 * \retval 1 on match
 * \retval 0 otherwise
 */
static int
libcfs_num_match(__u32 addr, struct list_head *numaddr)
{
        struct cfs_expr_list *el;

        LASSERT(!list_empty(numaddr));
        el = list_entry(numaddr->next, struct cfs_expr_list, el_link);

        return cfs_expr_list_match(addr, el);
}

struct netstrfns {
        int       nf_type;
        char    *nf_name;
        char    *nf_modname;
        void       (*nf_addr2str)(__u32 addr, char *str);
        int     (*nf_str2addr)(const char *str, int nob, __u32 *addr);
        int     (*nf_parse_addrlist)(char *str, int len,
                                        struct list_head *list);
        int     (*nf_match_addr)(__u32 addr, struct list_head *list);
};

static struct netstrfns  libcfs_netstrfns[] = {
        {/* .nf_type      */  LOLND,
         /* .nf_name      */  "lo",
         /* .nf_modname   */  "klolnd",
         /* .nf_addr2str  */  libcfs_decnum_addr2str,
         /* .nf_str2addr  */  libcfs_lo_str2addr,
         /* .nf_parse_addr*/  libcfs_num_parse,
         /* .nf_match_addr*/  libcfs_num_match},
        {/* .nf_type      */  SOCKLND,
         /* .nf_name      */  "tcp",
         /* .nf_modname   */  "ksocklnd",
         /* .nf_addr2str  */  libcfs_ip_addr2str,
         /* .nf_str2addr  */  libcfs_ip_str2addr,
         /* .nf_parse_addrlist*/  cfs_ip_addr_parse,
         /* .nf_match_addr*/  cfs_ip_addr_match},
        {/* .nf_type      */  O2IBLND,
         /* .nf_name      */  "o2ib",
         /* .nf_modname   */  "ko2iblnd",
         /* .nf_addr2str  */  libcfs_ip_addr2str,
         /* .nf_str2addr  */  libcfs_ip_str2addr,
         /* .nf_parse_addrlist*/  cfs_ip_addr_parse,
         /* .nf_match_addr*/  cfs_ip_addr_match},
        {/* .nf_type      */  CIBLND,
         /* .nf_name      */  "cib",
         /* .nf_modname   */  "kciblnd",
         /* .nf_addr2str  */  libcfs_ip_addr2str,
         /* .nf_str2addr  */  libcfs_ip_str2addr,
         /* .nf_parse_addrlist*/  cfs_ip_addr_parse,
         /* .nf_match_addr*/  cfs_ip_addr_match},
        {/* .nf_type      */  OPENIBLND,
         /* .nf_name      */  "openib",
         /* .nf_modname   */  "kopeniblnd",
         /* .nf_addr2str  */  libcfs_ip_addr2str,
         /* .nf_str2addr  */  libcfs_ip_str2addr,
         /* .nf_parse_addrlist*/  cfs_ip_addr_parse,
         /* .nf_match_addr*/  cfs_ip_addr_match},
        {/* .nf_type      */  IIBLND,
         /* .nf_name      */  "iib",
         /* .nf_modname   */  "kiiblnd",
         /* .nf_addr2str  */  libcfs_ip_addr2str,
         /* .nf_str2addr  */  libcfs_ip_str2addr,
         /* .nf_parse_addrlist*/  cfs_ip_addr_parse,
         /* .nf_match_addr*/  cfs_ip_addr_match},
        {/* .nf_type      */  VIBLND,
         /* .nf_name      */  "vib",
         /* .nf_modname   */  "kviblnd",
         /* .nf_addr2str  */  libcfs_ip_addr2str,
         /* .nf_str2addr  */  libcfs_ip_str2addr,
         /* .nf_parse_addrlist*/  cfs_ip_addr_parse,
         /* .nf_match_addr*/  cfs_ip_addr_match},
        {/* .nf_type      */  RALND,
         /* .nf_name      */  "ra",
         /* .nf_modname   */  "kralnd",
         /* .nf_addr2str  */  libcfs_ip_addr2str,
         /* .nf_str2addr  */  libcfs_ip_str2addr,
         /* .nf_parse_addrlist*/  cfs_ip_addr_parse,
         /* .nf_match_addr*/  cfs_ip_addr_match},
        {/* .nf_type      */  QSWLND,
         /* .nf_name      */  "elan",
         /* .nf_modname   */  "kqswlnd",
         /* .nf_addr2str  */  libcfs_decnum_addr2str,
         /* .nf_str2addr  */  libcfs_num_str2addr,
         /* .nf_parse_addrlist*/  libcfs_num_parse,
         /* .nf_match_addr*/  libcfs_num_match},
        {/* .nf_type      */  GMLND,
         /* .nf_name      */  "gm",
         /* .nf_modname   */  "kgmlnd",
         /* .nf_addr2str  */  libcfs_hexnum_addr2str,
         /* .nf_str2addr  */  libcfs_num_str2addr,
         /* .nf_parse_addrlist*/  libcfs_num_parse,
         /* .nf_match_addr*/  libcfs_num_match},
        {/* .nf_type      */  MXLND,
         /* .nf_name      */  "mx",
         /* .nf_modname   */  "kmxlnd",
         /* .nf_addr2str  */  libcfs_ip_addr2str,
         /* .nf_str2addr  */  libcfs_ip_str2addr,
         /* .nf_parse_addrlist*/  cfs_ip_addr_parse,
         /* .nf_match_addr*/  cfs_ip_addr_match},
        {/* .nf_type      */  PTLLND,
         /* .nf_name      */  "ptl",
         /* .nf_modname   */  "kptllnd",
         /* .nf_addr2str  */  libcfs_decnum_addr2str,
         /* .nf_str2addr  */  libcfs_num_str2addr,
         /* .nf_parse_addrlist*/  libcfs_num_parse,
         /* .nf_match_addr*/  libcfs_num_match},
        {/* .nf_type      */  GNILND,
         /* .nf_name      */  "gni",
         /* .nf_modname   */  "kgnilnd",
         /* .nf_addr2str  */  libcfs_decnum_addr2str,
         /* .nf_str2addr  */  libcfs_num_str2addr,
         /* .nf_parse_addrlist*/  libcfs_num_parse,
         /* .nf_match_addr*/  libcfs_num_match},
        /* placeholder for net0 alias.  It MUST BE THE LAST ENTRY */
        {/* .nf_type      */  -1},
};

static const int libcfs_nnetstrfns = ARRAY_SIZE(libcfs_netstrfns);

/* CAVEAT EMPTOR XscanfX
 * I use "%n" at the end of a sscanf format to detect trailing junk.  However
 * sscanf may return immediately if it sees the terminating '0' in a string, so
 * I initialise the %n variable to the expected length.  If sscanf sets it;
 * fine, if it doesn't, then the scan ended at the end of the string, which is
 * fine too :) */

static struct netstrfns *
libcfs_lnd2netstrfns(int lnd)
{
        int    i;

        if (lnd >= 0)
                for (i = 0; i < libcfs_nnetstrfns; i++)
                        if (lnd == libcfs_netstrfns[i].nf_type)
                                return &libcfs_netstrfns[i];

        return NULL;
}

static struct netstrfns *
libcfs_namenum2netstrfns(const char *name)
{
        struct netstrfns *nf;
        int            i;

        for (i = 0; i < libcfs_nnetstrfns; i++) {
                nf = &libcfs_netstrfns[i];
                if (nf->nf_type >= 0 &&
                    !strncmp(name, nf->nf_name, strlen(nf->nf_name)))
                        return nf;
        }
        return NULL;
}

static struct netstrfns *
libcfs_name2netstrfns(const char *name)
{
        int    i;

        for (i = 0; i < libcfs_nnetstrfns; i++)
                if (libcfs_netstrfns[i].nf_type >= 0 &&
                    !strcmp(libcfs_netstrfns[i].nf_name, name))
                        return &libcfs_netstrfns[i];

        return NULL;
}

int
libcfs_isknown_lnd(int type)
{
        return libcfs_lnd2netstrfns(type) != NULL;
}
EXPORT_SYMBOL(libcfs_isknown_lnd);

char *
libcfs_lnd2modname(int lnd)
{
        struct netstrfns *nf = libcfs_lnd2netstrfns(lnd);

        return (nf == NULL) ? NULL : nf->nf_modname;
}
EXPORT_SYMBOL(libcfs_lnd2modname);

char *
libcfs_lnd2str(int lnd)
{
        char       *str;
        struct netstrfns *nf = libcfs_lnd2netstrfns(lnd);

        if (nf != NULL)
                return nf->nf_name;

        str = libcfs_next_nidstring();
        snprintf(str, LNET_NIDSTR_SIZE, "?%d?", lnd);
        return str;
}
EXPORT_SYMBOL(libcfs_lnd2str);

int
libcfs_str2lnd(const char *str)
{
        struct netstrfns *nf = libcfs_name2netstrfns(str);

        if (nf != NULL)
                return nf->nf_type;

        return -1;
}
EXPORT_SYMBOL(libcfs_str2lnd);

char *
libcfs_net2str(__u32 net)
{
        int            lnd = LNET_NETTYP(net);
        int            num = LNET_NETNUM(net);
        struct netstrfns *nf  = libcfs_lnd2netstrfns(lnd);
        char         *str = libcfs_next_nidstring();

        if (nf == NULL)
                snprintf(str, LNET_NIDSTR_SIZE, "<%d:%d>", lnd, num);
        else if (num == 0)
                snprintf(str, LNET_NIDSTR_SIZE, "%s", nf->nf_name);
        else
                snprintf(str, LNET_NIDSTR_SIZE, "%s%d", nf->nf_name, num);

        return str;
}
EXPORT_SYMBOL(libcfs_net2str);

char *
libcfs_nid2str(lnet_nid_t nid)
{
        __u32        addr = LNET_NIDADDR(nid);
        __u32        net = LNET_NIDNET(nid);
        int            lnd = LNET_NETTYP(net);
        int            nnum = LNET_NETNUM(net);
        struct netstrfns *nf;
        char         *str;
        int            nob;

        if (nid == LNET_NID_ANY)
                return "<?>";

        nf = libcfs_lnd2netstrfns(lnd);
        str = libcfs_next_nidstring();

        if (nf == NULL)
                snprintf(str, LNET_NIDSTR_SIZE, "%x@<%d:%d>", addr, lnd, nnum);
        else {
                nf->nf_addr2str(addr, str);
                nob = strlen(str);
                if (nnum == 0)
                        snprintf(str + nob, LNET_NIDSTR_SIZE - nob, "@%s",
                                 nf->nf_name);
                else
                        snprintf(str + nob, LNET_NIDSTR_SIZE - nob, "@%s%d",
                                 nf->nf_name, nnum);
        }

        return str;
}
EXPORT_SYMBOL(libcfs_nid2str);

static struct netstrfns *
libcfs_str2net_internal(const char *str, __u32 *net)
{
        struct netstrfns *uninitialized_var(nf);
        int            nob;
        unsigned int   netnum;
        int            i;

        for (i = 0; i < libcfs_nnetstrfns; i++) {
                nf = &libcfs_netstrfns[i];
                if (nf->nf_type >= 0 &&
                    !strncmp(str, nf->nf_name, strlen(nf->nf_name)))
                        break;
        }

        if (i == libcfs_nnetstrfns)
                return NULL;

        nob = strlen(nf->nf_name);

        if (strlen(str) == (unsigned int)nob) {
                netnum = 0;
        } else {
                if (nf->nf_type == LOLND) /* net number not allowed */
                        return NULL;

                str += nob;
                i = strlen(str);
                if (sscanf(str, "%u%n", &netnum, &i) < 1 ||
                    i != (int)strlen(str))
                        return NULL;
        }

        *net = LNET_MKNET(nf->nf_type, netnum);
        return nf;
}

__u32
libcfs_str2net(const char *str)
{
        __u32  net;

        if (libcfs_str2net_internal(str, &net) != NULL)
                return net;

        return LNET_NIDNET(LNET_NID_ANY);
}
EXPORT_SYMBOL(libcfs_str2net);

lnet_nid_t
libcfs_str2nid(const char *str)
{
        const char       *sep = strchr(str, '@');
        struct netstrfns *nf;
        __u32        net;
        __u32        addr;

        if (sep != NULL) {
                nf = libcfs_str2net_internal(sep + 1, &net);
                if (nf == NULL)
                        return LNET_NID_ANY;
        } else {
                sep = str + strlen(str);
                net = LNET_MKNET(SOCKLND, 0);
                nf = libcfs_lnd2netstrfns(SOCKLND);
                LASSERT(nf != NULL);
        }

        if (!nf->nf_str2addr(str, (int)(sep - str), &addr))
                return LNET_NID_ANY;

        return LNET_MKNID(net, addr);
}
EXPORT_SYMBOL(libcfs_str2nid);

char *
libcfs_id2str(lnet_process_id_t id)
{
        char *str = libcfs_next_nidstring();

        if (id.pid == LNET_PID_ANY) {
                snprintf(str, LNET_NIDSTR_SIZE,
                         "LNET_PID_ANY-%s", libcfs_nid2str(id.nid));
                return str;
        }

        snprintf(str, LNET_NIDSTR_SIZE, "%s%u-%s",
                 ((id.pid & LNET_PID_USERFLAG) != 0) ? "U" : "",
                 (id.pid & ~LNET_PID_USERFLAG), libcfs_nid2str(id.nid));
        return str;
}
EXPORT_SYMBOL(libcfs_id2str);

int
libcfs_str2anynid(lnet_nid_t *nidp, const char *str)
{
        if (!strcmp(str, "*")) {
                *nidp = LNET_NID_ANY;
                return 1;
        }

        *nidp = libcfs_str2nid(str);
        return *nidp != LNET_NID_ANY;
}
EXPORT_SYMBOL(libcfs_str2anynid);

/**
 * Nid range list syntax.
 * \verbatim
 *
 * <nidlist>     :== <nidrange> [ ' ' <nidrange> ]
 * <nidrange>   :== <addrrange> '@' <net>
 * <addrrange>       :== '*' |
 *                     <ipaddr_range> |
 *                       <cfs_expr_list>
 * <ipaddr_range>    :== <cfs_expr_list>.<cfs_expr_list>.<cfs_expr_list>.
 *                       <cfs_expr_list>
 * <cfs_expr_list>   :== <number> |
 *                     <expr_list>
 * <expr_list>       :== '[' <range_expr> [ ',' <range_expr>] ']'
 * <range_expr>      :== <number> |
 *                     <number> '-' <number> |
 *                     <number> '-' <number> '/' <number>
 * <net>             :== <netname> | <netname><number>
 * <netname>     :== "lo" | "tcp" | "o2ib" | "cib" | "openib" | "iib" |
 *                     "vib" | "ra" | "elan" | "mx" | "ptl"
 * \endverbatim
 */

/**
 * Structure to represent \<nidrange\> token of the syntax.
 *
 * One of this is created for each \<net\> parsed.
 */
struct nidrange {
        /**
         * Link to list of this structures which is built on nid range
         * list parsing.
         */
        struct list_head nr_link;
        /**
         * List head for addrrange::ar_link.
         */
        struct list_head nr_addrranges;
        /**
         * Flag indicating that *@<net> is found.
         */
        int nr_all;
        /**
         * Pointer to corresponding element of libcfs_netstrfns.
         */
        struct netstrfns *nr_netstrfns;
        /**
         * Number of network. E.g. 5 if \<net\> is "elan5".
         */
        int nr_netnum;
};

/**
 * Structure to represent \<addrrange\> token of the syntax.
 */
struct addrrange {
        /**
         * Link to nidrange::nr_addrranges.
         */
        struct list_head ar_link;
        /**
         * List head for cfs_expr_list::el_list.
         */
        struct list_head ar_numaddr_ranges;
};

/**
 * Parses \<addrrange\> token on the syntax.
 *
 * Allocates struct addrrange and links to \a nidrange via
 * (nidrange::nr_addrranges)
 *
 * \retval 1 if \a src parses to '*' | \<ipaddr_range\> | \<cfs_expr_list\>
 * \retval 0 otherwise
 */
static int
parse_addrange(const struct cfs_lstr *src, struct nidrange *nidrange)
{
        struct addrrange *addrrange;

        if (src->ls_len == 1 && src->ls_str[0] == '*') {
                nidrange->nr_all = 1;
                return 1;
        }

        LIBCFS_ALLOC(addrrange, sizeof(struct addrrange));
        if (addrrange == NULL)
                return 0;
        list_add_tail(&addrrange->ar_link, &nidrange->nr_addrranges);
        INIT_LIST_HEAD(&addrrange->ar_numaddr_ranges);

        return nidrange->nr_netstrfns->nf_parse_addrlist(src->ls_str,
                                                src->ls_len,
                                                &addrrange->ar_numaddr_ranges);
}

/**
 * Finds or creates struct nidrange.
 *
 * Checks if \a src is a valid network name, looks for corresponding
 * nidrange on the ist of nidranges (\a nidlist), creates new struct
 * nidrange if it is not found.
 *
 * \retval pointer to struct nidrange matching network specified via \a src
 * \retval NULL if \a src does not match any network
 */
static struct nidrange *
add_nidrange(const struct cfs_lstr *src,
             struct list_head *nidlist)
{
        struct netstrfns *nf;
        struct nidrange *nr;
        int endlen;
        unsigned netnum;

        if (src->ls_len >= LNET_NIDSTR_SIZE)
                return NULL;

        nf = libcfs_namenum2netstrfns(src->ls_str);
        if (nf == NULL)
                return NULL;
        endlen = src->ls_len - strlen(nf->nf_name);
        if (endlen == 0)
                /* network name only, e.g. "elan" or "tcp" */
                netnum = 0;
        else {
                /* e.g. "elan25" or "tcp23", refuse to parse if
                 * network name is not appended with decimal or
                 * hexadecimal number */
                if (!cfs_str2num_check(src->ls_str + strlen(nf->nf_name),
                                       endlen, &netnum, 0, MAX_NUMERIC_VALUE))
                        return NULL;
        }

        list_for_each_entry(nr, nidlist, nr_link) {
                if (nr->nr_netstrfns != nf)
                        continue;
                if (nr->nr_netnum != netnum)
                        continue;
                return nr;
        }

        LIBCFS_ALLOC(nr, sizeof(struct nidrange));
        if (nr == NULL)
                return NULL;
        list_add_tail(&nr->nr_link, nidlist);
        INIT_LIST_HEAD(&nr->nr_addrranges);
        nr->nr_netstrfns = nf;
        nr->nr_all = 0;
        nr->nr_netnum = netnum;

        return nr;
}

/**
 * Parses \<nidrange\> token of the syntax.
 *
 * \retval 1 if \a src parses to \<addrrange\> '@' \<net\>
 * \retval 0 otherwise
 */
static int
parse_nidrange(struct cfs_lstr *src, struct list_head *nidlist)
{
        struct cfs_lstr addrrange;
        struct cfs_lstr net;
        struct cfs_lstr tmp;
        struct nidrange *nr;

        tmp = *src;
        if (cfs_gettok(src, '@', &addrrange) == 0)
                goto failed;

        if (cfs_gettok(src, '@', &net) == 0 || src->ls_str != NULL)
                goto failed;

        nr = add_nidrange(&net, nidlist);
        if (nr == NULL)
                goto failed;

        if (parse_addrange(&addrrange, nr) != 0)
                goto failed;

        return 1;
 failed:
        CWARN("can't parse nidrange: \"%.*s\"\n", tmp.ls_len, tmp.ls_str);
        return 0;
}

/**
 * Frees addrrange structures of \a list.
 *
 * For each struct addrrange structure found on \a list it frees
 * cfs_expr_list list attached to it and frees the addrrange itself.
 *
 * \retval none
 */
static void
free_addrranges(struct list_head *list)
{
        while (!list_empty(list)) {
                struct addrrange *ar;

                ar = list_entry(list->next, struct addrrange, ar_link);

                cfs_expr_list_free_list(&ar->ar_numaddr_ranges);
                list_del(&ar->ar_link);
                LIBCFS_FREE(ar, sizeof(struct addrrange));
        }
}

/**
 * Frees nidrange strutures of \a list.
 *
 * For each struct nidrange structure found on \a list it frees
 * addrrange list attached to it and frees the nidrange itself.
 *
 * \retval none
 */
void
cfs_free_nidlist(struct list_head *list)
{
        struct list_head *pos, *next;
        struct nidrange *nr;

        list_for_each_safe(pos, next, list) {
                nr = list_entry(pos, struct nidrange, nr_link);
                free_addrranges(&nr->nr_addrranges);
                list_del(pos);
                LIBCFS_FREE(nr, sizeof(struct nidrange));
        }
}
EXPORT_SYMBOL(cfs_free_nidlist);

/**
 * Parses nid range list.
 *
 * Parses with rigorous syntax and overflow checking \a str into
 * \<nidrange\> [ ' ' \<nidrange\> ], compiles \a str into set of
 * structures and links that structure to \a nidlist. The resulting
 * list can be used to match a NID againts set of NIDS defined by \a
 * str.
 * \see cfs_match_nid
 *
 * \retval 1 on success
 * \retval 0 otherwise
 */
int
cfs_parse_nidlist(char *str, int len, struct list_head *nidlist)
{
        struct cfs_lstr src;
        struct cfs_lstr res;
        int rc;

        src.ls_str = str;
        src.ls_len = len;
        INIT_LIST_HEAD(nidlist);
        while (src.ls_str) {
                rc = cfs_gettok(&src, ' ', &res);
                if (rc == 0) {
                        cfs_free_nidlist(nidlist);
                        return 0;
                }
                rc = parse_nidrange(&res, nidlist);
                if (rc == 0) {
                        cfs_free_nidlist(nidlist);
                        return 0;
                }
        }
        return 1;
}
EXPORT_SYMBOL(cfs_parse_nidlist);

/**
 * Matches a nid (\a nid) against the compiled list of nidranges (\a nidlist).
 *
 * \see cfs_parse_nidlist()
 *
 * \retval 1 on match
 * \retval 0  otherwises
 */
int cfs_match_nid(lnet_nid_t nid, struct list_head *nidlist)
{
        struct nidrange *nr;
        struct addrrange *ar;

        list_for_each_entry(nr, nidlist, nr_link) {
                if (nr->nr_netstrfns->nf_type != LNET_NETTYP(LNET_NIDNET(nid)))
                        continue;
                if (nr->nr_netnum != LNET_NETNUM(LNET_NIDNET(nid)))
                        continue;
                if (nr->nr_all)
                        return 1;
                list_for_each_entry(ar, &nr->nr_addrranges, ar_link)
                        if (nr->nr_netstrfns->nf_match_addr(LNET_NIDADDR(nid),
                                                       &ar->ar_numaddr_ranges))
                                return 1;
        }
        return 0;
}
EXPORT_SYMBOL(cfs_match_nid);