/*
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Copyright (c) 2001 by Internet Software Consortium.
 *
 * 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 ISC 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.
 */

#include <port_before.h>
#include <netdb.h>
#include <port_after.h>

#ifdef DO_PTHREADS
#include <pthread.h>
#include <stdlib.h>
#endif

static const char *gai_errlist[] = {
        "no error",
        "address family not supported for name",/*%< EAI_ADDRFAMILY */
        "temporary failure",                    /*%< EAI_AGAIN */
        "invalid flags",                        /*%< EAI_BADFLAGS */
        "permanent failure",                    /*%< EAI_FAIL */
        "address family not supported",         /*%< EAI_FAMILY */
        "memory failure",                       /*%< EAI_MEMORY */
        "no address",                           /*%< EAI_NODATA */
        "unknown name or service",              /*%< EAI_NONAME */
        "service not supported for socktype",   /*%< EAI_SERVICE */
        "socktype not supported",               /*%< EAI_SOCKTYPE */
        "system failure",                       /*%< EAI_SYSTEM */
        "bad hints",                            /*%< EAI_BADHINTS */
        "bad protocol",                         /*%< EAI_PROTOCOL */
        "unknown error"                         /*%< Must be last. */
};

static const int gai_nerr = (sizeof(gai_errlist)/sizeof(*gai_errlist));

#define EAI_BUFSIZE 128

const char *
gai_strerror(int ecode) {
#ifndef DO_PTHREADS
        static char buf[EAI_BUFSIZE];
#else   /* DO_PTHREADS */
#ifndef LIBBIND_MUTEX_INITIALIZER
#define LIBBIND_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER
#endif
        static pthread_mutex_t lock = LIBBIND_MUTEX_INITIALIZER;
        static pthread_key_t key;
        static int once = 0;
        char *buf;
#endif

        if (ecode >= 0 && ecode < (gai_nerr - 1))
                return (gai_errlist[ecode]);

#ifdef DO_PTHREADS
        if (!once) {
                if (pthread_mutex_lock(&lock) != 0)
                        goto unknown;
                if (!once) {
                        if (pthread_key_create(&key, free) != 0) {
                                (void)pthread_mutex_unlock(&lock);
                                goto unknown;
                        }
                        once = 1;
                }
                if (pthread_mutex_unlock(&lock) != 0)
                        goto unknown;
        }

        buf = pthread_getspecific(key);
        if (buf == NULL) {
                buf = malloc(EAI_BUFSIZE);
                if (buf == NULL)
                        goto unknown;
                if (pthread_setspecific(key, buf) != 0) {
                        free(buf);
                        goto unknown;
                }
        }
#endif
        /*
         * XXX This really should be snprintf(buf, EAI_BUFSIZE, ...).
         * It is safe until message catalogs are used.
         */
        sprintf(buf, "%s: %d", gai_errlist[gai_nerr - 1], ecode);
        return (buf);

#ifdef DO_PTHREADS
 unknown:
        return ("unknown error");
#endif
}

/*! \file */