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[/] [openrisc/] [trunk/] [gnu-stable/] [newlib-1.18.0/] [newlib/] [libc/] [sys/] [linux/] [net/] [res_query.c] - Blame information for rev 859

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/*
 * Copyright (c) 1988, 1993
 *    The Regents of the University of California.  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.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 */
 
/*
 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 *
 * 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, and that
 * the name of Digital Equipment Corporation not be used in advertising or
 * publicity pertaining to distribution of the document or software without
 * specific, written prior permission.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 * CORPORATION 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) 1996-1999 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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM 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.
 */
 
#if defined(LIBC_SCCS) && !defined(lint)
static const char sccsid[] = "@(#)res_query.c   8.1 (Berkeley) 6/4/93";
static const char rcsid[] = "$BINDId: res_query.c,v 8.20 2000/02/29 05:39:12 vixie Exp $";
#endif /* LIBC_SCCS and not lint */
 
#include <sys/types.h>
#include <sys/param.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <ctype.h>
#include <errno.h>
#include <netdb.h>
#include <resolv.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libc-symbols.h"
 
/* Options.  Leave them on. */
/* #undef DEBUG */
 
#if PACKETSZ > 65536
#define MAXPACKET       PACKETSZ
#else
#define MAXPACKET       65536
#endif
 
#define QUERYSIZE       (HFIXEDSZ + QFIXEDSZ + MAXCDNAME + 1)
 
static int
__libc_res_nquerydomain(res_state statp, const char *name, const char *domain,
                        int class, int type, u_char *answer, int anslen,
                        u_char **answerp);
 
/*
 * Formulate a normal query, send, and await answer.
 * Returned answer is placed in supplied buffer "answer".
 * Perform preliminary check of answer, returning success only
 * if no error is indicated and the answer count is nonzero.
 * Return the size of the response on success, -1 on error.
 * Error number is left in H_ERRNO.
 *
 * Caller must parse answer and determine whether it answers the question.
 */
int
__libc_res_nquery(res_state statp,
                  const char *name,     /* domain name */
                  int class, int type,  /* class and type of query */
                  u_char *answer,       /* buffer to put answer */
                  int anslen,           /* size of answer buffer */
                  u_char **answerp)     /* if buffer needs to be enlarged */
{
        u_char *buf;
        HEADER *hp = (HEADER *) answer;
        int n, use_malloc = 0;
 
        hp->rcode = NOERROR;    /* default */
 
        buf = alloca (QUERYSIZE);
 
#ifdef DEBUG
        if (statp->options & RES_DEBUG)
                printf(";; res_query(%s, %d, %d)\n", name, class, type);
#endif
 
        n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL,
                         buf, QUERYSIZE);
        if (__builtin_expect (n <= 0, 0)) {
                /* Retry just in case res_nmkquery failed because of too
                   short buffer.  Shouldn't happen.  */
                buf = malloc (MAXPACKET);
                if (buf != NULL) {
                        use_malloc = 1;
                        n = res_nmkquery(statp, QUERY, name, class, type, NULL,
                                         0, NULL, buf, MAXPACKET);
                }
        }
        if (__builtin_expect (n <= 0, 0)) {
#ifdef DEBUG
                if (statp->options & RES_DEBUG)
                        printf(";; res_query: mkquery failed\n");
#endif
                RES_SET_H_ERRNO(statp, NO_RECOVERY);
                if (use_malloc)
                        free (buf);
                return (n);
        }
        n = __libc_res_nsend(statp, buf, n, answer, anslen, answerp);
        if (use_malloc)
                free (buf);
        if (n < 0) {
#ifdef DEBUG
                if (statp->options & RES_DEBUG)
                        printf(";; res_query: send error\n");
#endif
                RES_SET_H_ERRNO(statp, TRY_AGAIN);
                return (n);
        }
 
        if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
#ifdef DEBUG
                if (statp->options & RES_DEBUG)
                        printf(";; rcode = %d, ancount=%d\n", hp->rcode,
                            ntohs(hp->ancount));
#endif
                switch (hp->rcode) {
                case NXDOMAIN:
                        RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
                        break;
                case SERVFAIL:
                        RES_SET_H_ERRNO(statp, TRY_AGAIN);
                        break;
                case NOERROR:
                        RES_SET_H_ERRNO(statp, NO_DATA);
                        break;
                case FORMERR:
                case NOTIMP:
                case REFUSED:
                default:
                        RES_SET_H_ERRNO(statp, NO_RECOVERY);
                        break;
                }
                return (-1);
        }
        return (n);
}
libresolv_hidden_def (__libc_res_nquery)
 
int
res_nquery(res_state statp,
           const char *name,    /* domain name */
           int class, int type, /* class and type of query */
           u_char *answer,      /* buffer to put answer */
           int anslen)          /* size of answer buffer */
{
        return __libc_res_nquery(statp, name, class, type, answer, anslen,
                                 NULL);
}
libresolv_hidden_def (res_nquery)
 
/*
 * Formulate a normal query, send, and retrieve answer in supplied buffer.
 * Return the size of the response on success, -1 on error.
 * If enabled, implement search rules until answer or unrecoverable failure
 * is detected.  Error code, if any, is left in H_ERRNO.
 */
int
__libc_res_nsearch(res_state statp,
            const char *name,   /* domain name */
            int class, int type,        /* class and type of query */
            u_char *answer,     /* buffer to put answer */
            int anslen,         /* size of answer */
            u_char **answerp)
{
        const char *cp, * const *domain;
        HEADER *hp = (HEADER *) answer;
        char tmp[NS_MAXDNAME];
        u_int dots;
        int trailing_dot, ret, saved_herrno;
        int got_nodata = 0, got_servfail = 0, root_on_list = 0;
        int tried_as_is = 0;
 
        __set_errno (0);
        RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);  /* True if we never query. */
 
        dots = 0;
        for (cp = name; *cp != '\0'; cp++)
                dots += (*cp == '.');
        trailing_dot = 0;
        if (cp > name && *--cp == '.')
                trailing_dot++;
 
        /* If there aren't any dots, it could be a user-level alias. */
        if (!dots && (cp = res_hostalias(statp, name, tmp, sizeof tmp))!= NULL)
                return (__libc_res_nquery(statp, cp, class, type, answer,
                                          anslen, answerp));
 
#ifdef DEBUG
        if (statp->options & RES_DEBUG)
                printf("dots=%d, statp->ndots=%d, trailing_dot=%d, name=%s\n",
                       (int)dots,(int)statp->ndots,(int)trailing_dot,name);
#endif
 
        /*
         * If there are enough dots in the name, let's just give it a
         * try 'as is'. The threshold can be set with the "ndots" option.
         * Also, query 'as is', if there is a trailing dot in the name.
         */
        saved_herrno = -1;
        if (dots >= statp->ndots || trailing_dot) {
                ret = __libc_res_nquerydomain(statp, name, NULL, class, type,
                                              answer, anslen, answerp);
                if (ret > 0 || trailing_dot)
                        return (ret);
                saved_herrno = h_errno;
                tried_as_is++;
                if (answerp && *answerp != answer) {
                        answer = *answerp;
                        anslen = MAXPACKET;
                }
        }
 
        /*
         * We do at least one level of search if
         *      - there is no dot and RES_DEFNAME is set, or
         *      - there is at least one dot, there is no trailing dot,
         *        and RES_DNSRCH is set.
         */
        if ((!dots && (statp->options & RES_DEFNAMES) != 0) ||
            (dots && !trailing_dot && (statp->options & RES_DNSRCH) != 0)) {
                int done = 0;
 
                for (domain = (const char * const *)statp->dnsrch;
                     *domain && !done;
                     domain++) {
 
                        if (domain[0][0] == '\0' ||
                            (domain[0][0] == '.' && domain[0][1] == '\0'))
                                root_on_list++;
 
                        ret = __libc_res_nquerydomain(statp, name, *domain,
                                                      class, type,
                                                      answer, anslen, answerp);
                        if (ret > 0)
                                return (ret);
 
                        if (answerp && *answerp != answer) {
                                answer = *answerp;
                                anslen = MAXPACKET;
                        }
 
                        /*
                         * If no server present, give up.
                         * If name isn't found in this domain,
                         * keep trying higher domains in the search list
                         * (if that's enabled).
                         * On a NO_DATA error, keep trying, otherwise
                         * a wildcard entry of another type could keep us
                         * from finding this entry higher in the domain.
                         * If we get some other error (negative answer or
                         * server failure), then stop searching up,
                         * but try the input name below in case it's
                         * fully-qualified.
                         */
                        if (errno == ECONNREFUSED) {
                                RES_SET_H_ERRNO(statp, TRY_AGAIN);
                                return (-1);
                        }
 
                        switch (statp->res_h_errno) {
                        case NO_DATA:
                                got_nodata++;
                                /* FALLTHROUGH */
                        case HOST_NOT_FOUND:
                                /* keep trying */
                                break;
                        case TRY_AGAIN:
                                if (hp->rcode == SERVFAIL) {
                                        /* try next search element, if any */
                                        got_servfail++;
                                        break;
                                }
                                /* FALLTHROUGH */
                        default:
                                /* anything else implies that we're done */
                                done++;
                        }
 
                        /* if we got here for some reason other than DNSRCH,
                         * we only wanted one iteration of the loop, so stop.
                         */
                        if ((statp->options & RES_DNSRCH) == 0)
                                done++;
                }
        }
 
        /*
         * If the name has any dots at all, and no earlier 'as-is' query
         * for the name, and "." is not on the search list, then try an as-is
         * query now.
         */
        if (dots && !(tried_as_is || root_on_list)) {
                ret = __libc_res_nquerydomain(statp, name, NULL, class, type,
                                              answer, anslen, answerp);
                if (ret > 0)
                        return (ret);
        }
 
        /* if we got here, we didn't satisfy the search.
         * if we did an initial full query, return that query's H_ERRNO
         * (note that we wouldn't be here if that query had succeeded).
         * else if we ever got a nodata, send that back as the reason.
         * else send back meaningless H_ERRNO, that being the one from
         * the last DNSRCH we did.
         */
        if (saved_herrno != -1)
                RES_SET_H_ERRNO(statp, saved_herrno);
        else if (got_nodata)
                RES_SET_H_ERRNO(statp, NO_DATA);
        else if (got_servfail)
                RES_SET_H_ERRNO(statp, TRY_AGAIN);
        return (-1);
}
libresolv_hidden_def (__libc_res_nsearch)
 
int
res_nsearch(res_state statp,
            const char *name,   /* domain name */
            int class, int type,        /* class and type of query */
            u_char *answer,     /* buffer to put answer */
            int anslen)         /* size of answer */
{
        return __libc_res_nsearch(statp, name, class, type, answer,
                                  anslen, NULL);
}
libresolv_hidden_def (res_nsearch)
 
/*
 * Perform a call on res_query on the concatenation of name and domain,
 * removing a trailing dot from name if domain is NULL.
 */
static int
__libc_res_nquerydomain(res_state statp,
            const char *name,
            const char *domain,
            int class, int type,        /* class and type of query */
            u_char *answer,             /* buffer to put answer */
            int anslen,                 /* size of answer */
            u_char **answerp)
{
        char nbuf[MAXDNAME];
        const char *longname = nbuf;
        int n, d;
 
#ifdef DEBUG
        if (statp->options & RES_DEBUG)
                printf(";; res_nquerydomain(%s, %s, %d, %d)\n",
                       name, domain?domain:"<Nil>", class, type);
#endif
        if (domain == NULL) {
                /*
                 * Check for trailing '.';
                 * copy without '.' if present.
                 */
                n = strlen(name);
                if (n >= MAXDNAME) {
                        RES_SET_H_ERRNO(statp, NO_RECOVERY);
                        return (-1);
                }
                n--;
                if (n >= 0 && name[n] == '.') {
                        strncpy(nbuf, name, n);
                        nbuf[n] = '\0';
                } else
                        longname = name;
        } else {
                n = strlen(name);
                d = strlen(domain);
                if (n + d + 1 >= MAXDNAME) {
                        RES_SET_H_ERRNO(statp, NO_RECOVERY);
                        return (-1);
                }
                sprintf(nbuf, "%s.%s", name, domain);
        }
        return (__libc_res_nquery(statp, longname, class, type, answer,
                                  anslen, answerp));
}
 
int
res_nquerydomain(res_state statp,
            const char *name,
            const char *domain,
            int class, int type,        /* class and type of query */
            u_char *answer,             /* buffer to put answer */
            int anslen)         /* size of answer */
{
        return __libc_res_nquerydomain(statp, name, domain, class, type,
                                       answer, anslen, NULL);
}
libresolv_hidden_def (res_nquerydomain)
 
const char *
res_hostalias(const res_state statp, const char *name, char *dst, size_t siz) {
        char *file, *cp1, *cp2;
        char buf[BUFSIZ];
        FILE *fp;
 
        if (statp->options & RES_NOALIASES)
                return (NULL);
        file = getenv("HOSTALIASES");
        if (file == NULL || (fp = fopen(file, "r")) == NULL)
                return (NULL);
        setbuf(fp, NULL);
        buf[sizeof(buf) - 1] = '\0';
        while (fgets(buf, sizeof(buf), fp)) {
                for (cp1 = buf; *cp1 && !isspace(*cp1); ++cp1)
                        ;
                if (!*cp1)
                        break;
                *cp1 = '\0';
                if (ns_samename(buf, name) == 1) {
                        while (isspace(*++cp1))
                                ;
                        if (!*cp1)
                                break;
                        for (cp2 = cp1 + 1; *cp2 && !isspace(*cp2); ++cp2)
                                ;
                        *cp2 = '\0';
                        strncpy(dst, cp1, siz - 1);
                        dst[siz - 1] = '\0';
                        fclose(fp);
                        return (dst);
                }
        }
        fclose(fp);
        return (NULL);
}
libresolv_hidden_def (res_hostalias)

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Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-stable/] [newlib-1.18.0/] [newlib/] [libc/] [sys/] [linux/] [net/] [res_query.c] - Blame information for rev 859

Line No.	Rev	Author	Line
1	207	jeremybenn	`/*`
2			`* Copyright (c) 1988, 1993`
3			`* The Regents of the University of California. All rights reserved.`
4			`*`
5			`* Redistribution and use in source and binary forms, with or without`
6			`* modification, are permitted provided that the following conditions`
7			`* are met:`
8			`* 1. Redistributions of source code must retain the above copyright`
9			`* notice, this list of conditions and the following disclaimer.`
10			`* 2. Redistributions in binary form must reproduce the above copyright`
11			`* notice, this list of conditions and the following disclaimer in the`
12			`* documentation and/or other materials provided with the distribution.`
13			`* 4. Neither the name of the University nor the names of its contributors`
14			`* may be used to endorse or promote products derived from this software`
15			`* without specific prior written permission.`
16			`*`
17			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18			`* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE`
19			`* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE`
20			`* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE`
21			`* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL`
22			`* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS`
23			`* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)`
24			`* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT`
25			`* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY`
26			`* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF`
27			`* SUCH DAMAGE.`
28			`*/`
29
30			`/*`
31			`* Portions Copyright (c) 1993 by Digital Equipment Corporation.`
32			`*`
33			`* Permission to use, copy, modify, and distribute this software for any`
34			`* purpose with or without fee is hereby granted, provided that the above`
35			`* copyright notice and this permission notice appear in all copies, and that`
36			`* the name of Digital Equipment Corporation not be used in advertising or`
37			`* publicity pertaining to distribution of the document or software without`
38			`* specific, written prior permission.`
39			`*`
40			`* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL`
41			`* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES`
42			`* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT`
43			`* CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL`
44			`* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR`
45			`* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS`
46			`* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS`
47			`* SOFTWARE.`
48			`*/`
49
50			`/*`
51			`* Portions Copyright (c) 1996-1999 by Internet Software Consortium.`
52			`*`
53			`* Permission to use, copy, modify, and distribute this software for any`
54			`* purpose with or without fee is hereby granted, provided that the above`
55			`* copyright notice and this permission notice appear in all copies.`
56			`*`
57			`* THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS`
58			`* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES`
59			`* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE`
60			`* CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL`
61			`* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR`
62			`* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS`
63			`* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS`
64			`* SOFTWARE.`
65			`*/`
66
67			`#if defined(LIBC_SCCS) && !defined(lint)`
68			`static const char sccsid[] = "@(#)res_query.c 8.1 (Berkeley) 6/4/93";`
69			`static const char rcsid[] = "$BINDId: res_query.c,v 8.20 2000/02/29 05:39:12 vixie Exp $";`
70			`#endif /* LIBC_SCCS and not lint */`
71
72			`#include <sys/types.h>`
73			`#include <sys/param.h>`
74			`#include <netinet/in.h>`
75			`#include <arpa/inet.h>`
76			`#include <arpa/nameser.h>`
77			`#include <ctype.h>`
78			`#include <errno.h>`
79			`#include <netdb.h>`
80			`#include <resolv.h>`
81			`#include <stdio.h>`
82			`#include <stdlib.h>`
83			`#include <string.h>`
84			`#include "libc-symbols.h"`
85
86			`/* Options. Leave them on. */`
87			`/* #undef DEBUG */`
88
89			`#if PACKETSZ > 65536`
90			`#define MAXPACKET PACKETSZ`
91			`#else`
92			`#define MAXPACKET 65536`
93			`#endif`
94
95			`#define QUERYSIZE (HFIXEDSZ + QFIXEDSZ + MAXCDNAME + 1)`
96
97			`static int`
98			`__libc_res_nquerydomain(res_state statp, const char name, const char domain,`
99			`int class, int type, u_char *answer, int anslen,`
100			`u_char **answerp);`
101
102			`/*`
103			`* Formulate a normal query, send, and await answer.`
104			`* Returned answer is placed in supplied buffer "answer".`
105			`* Perform preliminary check of answer, returning success only`
106			`* if no error is indicated and the answer count is nonzero.`
107			`* Return the size of the response on success, -1 on error.`
108			`* Error number is left in H_ERRNO.`
109			`*`
110			`* Caller must parse answer and determine whether it answers the question.`
111			`*/`
112			`int`
113			`__libc_res_nquery(res_state statp,`
114			`const char name, / domain name */`
115			`int class, int type, /* class and type of query */`
116			`u_char answer, / buffer to put answer */`
117			`int anslen, /* size of answer buffer */`
118			`u_char *answerp) / if buffer needs to be enlarged */`
119			`{`
120			`u_char *buf;`
121			`HEADER hp = (HEADER ) answer;`
122			`int n, use_malloc = 0;`
123
124			`hp->rcode = NOERROR; /* default */`
125
126			`buf = alloca (QUERYSIZE);`
127
128			`#ifdef DEBUG`
129			`if (statp->options & RES_DEBUG)`
130			`printf(";; res_query(%s, %d, %d)\n", name, class, type);`
131			`#endif`
132
133			`n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL,`
134			`buf, QUERYSIZE);`
135			`if (__builtin_expect (n <= 0, 0)) {`
136			`/* Retry just in case res_nmkquery failed because of too`
137			`short buffer. Shouldn't happen. */`
138			`buf = malloc (MAXPACKET);`
139			`if (buf != NULL) {`
140			`use_malloc = 1;`
141			`n = res_nmkquery(statp, QUERY, name, class, type, NULL,`
142			`0, NULL, buf, MAXPACKET);`
143			`}`
144			`}`
145			`if (__builtin_expect (n <= 0, 0)) {`
146			`#ifdef DEBUG`
147			`if (statp->options & RES_DEBUG)`
148			`printf(";; res_query: mkquery failed\n");`
149			`#endif`
150			`RES_SET_H_ERRNO(statp, NO_RECOVERY);`
151			`if (use_malloc)`
152			`free (buf);`
153			`return (n);`
154			`}`
155			`n = __libc_res_nsend(statp, buf, n, answer, anslen, answerp);`
156			`if (use_malloc)`
157			`free (buf);`
158			`if (n < 0) {`
159			`#ifdef DEBUG`
160			`if (statp->options & RES_DEBUG)`
161			`printf(";; res_query: send error\n");`
162			`#endif`
163			`RES_SET_H_ERRNO(statp, TRY_AGAIN);`
164			`return (n);`
165			`}`
166
167			`if (hp->rcode != NOERROR \|\| ntohs(hp->ancount) == 0) {`
168			`#ifdef DEBUG`
169			`if (statp->options & RES_DEBUG)`
170			`printf(";; rcode = %d, ancount=%d\n", hp->rcode,`
171			`ntohs(hp->ancount));`
172			`#endif`
173			`switch (hp->rcode) {`
174			`case NXDOMAIN:`
175			`RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);`
176			`break;`
177			`case SERVFAIL:`
178			`RES_SET_H_ERRNO(statp, TRY_AGAIN);`
179			`break;`
180			`case NOERROR:`
181			`RES_SET_H_ERRNO(statp, NO_DATA);`
182			`break;`
183			`case FORMERR:`
184			`case NOTIMP:`
185			`case REFUSED:`
186			`default:`
187			`RES_SET_H_ERRNO(statp, NO_RECOVERY);`
188			`break;`
189			`}`
190			`return (-1);`
191			`}`
192			`return (n);`
193			`}`
194			`libresolv_hidden_def (__libc_res_nquery)`
195
196			`int`
197			`res_nquery(res_state statp,`
198			`const char name, / domain name */`
199			`int class, int type, /* class and type of query */`
200			`u_char answer, / buffer to put answer */`
201			`int anslen) /* size of answer buffer */`
202			`{`
203			`return __libc_res_nquery(statp, name, class, type, answer, anslen,`
204			`NULL);`
205			`}`
206			`libresolv_hidden_def (res_nquery)`
207
208			`/*`
209			`* Formulate a normal query, send, and retrieve answer in supplied buffer.`
210			`* Return the size of the response on success, -1 on error.`
211			`* If enabled, implement search rules until answer or unrecoverable failure`
212			`* is detected. Error code, if any, is left in H_ERRNO.`
213			`*/`
214			`int`
215			`__libc_res_nsearch(res_state statp,`
216			`const char name, / domain name */`
217			`int class, int type, /* class and type of query */`
218			`u_char answer, / buffer to put answer */`
219			`int anslen, /* size of answer */`
220			`u_char **answerp)`
221			`{`
222			`const char cp, const *domain;`
223			`HEADER hp = (HEADER ) answer;`
224			`char tmp[NS_MAXDNAME];`
225			`u_int dots;`
226			`int trailing_dot, ret, saved_herrno;`
227			`int got_nodata = 0, got_servfail = 0, root_on_list = 0;`
228			`int tried_as_is = 0;`
229
230			`__set_errno (0);`
231			`RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); /* True if we never query. */`
232
233			`dots = 0;`
234			`for (cp = name; *cp != '\0'; cp++)`
235			`dots += (*cp == '.');`
236			`trailing_dot = 0;`
237			`if (cp > name && *--cp == '.')`
238			`trailing_dot++;`
239
240			`/* If there aren't any dots, it could be a user-level alias. */`
241			`if (!dots && (cp = res_hostalias(statp, name, tmp, sizeof tmp))!= NULL)`
242			`return (__libc_res_nquery(statp, cp, class, type, answer,`
243			`anslen, answerp));`
244
245			`#ifdef DEBUG`
246			`if (statp->options & RES_DEBUG)`
247			`printf("dots=%d, statp->ndots=%d, trailing_dot=%d, name=%s\n",`
248			`(int)dots,(int)statp->ndots,(int)trailing_dot,name);`
249			`#endif`
250
251			`/*`
252			`* If there are enough dots in the name, let's just give it a`
253			`* try 'as is'. The threshold can be set with the "ndots" option.`
254			`* Also, query 'as is', if there is a trailing dot in the name.`
255			`*/`
256			`saved_herrno = -1;`
257			`if (dots >= statp->ndots \|\| trailing_dot) {`
258			`ret = __libc_res_nquerydomain(statp, name, NULL, class, type,`
259			`answer, anslen, answerp);`
260			`if (ret > 0 \|\| trailing_dot)`
261			`return (ret);`
262			`saved_herrno = h_errno;`
263			`tried_as_is++;`
264			`if (answerp && *answerp != answer) {`
265			`answer = *answerp;`
266			`anslen = MAXPACKET;`
267			`}`
268			`}`
269
270			`/*`
271			`* We do at least one level of search if`
272			`* - there is no dot and RES_DEFNAME is set, or`
273			`* - there is at least one dot, there is no trailing dot,`
274			`* and RES_DNSRCH is set.`
275			`*/`
276			`if ((!dots && (statp->options & RES_DEFNAMES) != 0) \|\|`
277			`(dots && !trailing_dot && (statp->options & RES_DNSRCH) != 0)) {`
278			`int done = 0;`
279
280			`for (domain = (const char * const *)statp->dnsrch;`
281			`*domain && !done;`
282			`domain++) {`
283
284			`if (domain[0][0] == '\0' \|\|`
285			`(domain[0][0] == '.' && domain[0][1] == '\0'))`
286			`root_on_list++;`
287
288			`ret = __libc_res_nquerydomain(statp, name, *domain,`
289			`class, type,`
290			`answer, anslen, answerp);`
291			`if (ret > 0)`
292			`return (ret);`
293
294			`if (answerp && *answerp != answer) {`
295			`answer = *answerp;`
296			`anslen = MAXPACKET;`
297			`}`
298
299			`/*`
300			`* If no server present, give up.`
301			`* If name isn't found in this domain,`
302			`* keep trying higher domains in the search list`
303			`* (if that's enabled).`
304			`* On a NO_DATA error, keep trying, otherwise`
305			`* a wildcard entry of another type could keep us`
306			`* from finding this entry higher in the domain.`
307			`* If we get some other error (negative answer or`
308			`* server failure), then stop searching up,`
309			`* but try the input name below in case it's`
310			`* fully-qualified.`
311			`*/`
312			`if (errno == ECONNREFUSED) {`
313			`RES_SET_H_ERRNO(statp, TRY_AGAIN);`
314			`return (-1);`
315			`}`
316
317			`switch (statp->res_h_errno) {`
318			`case NO_DATA:`
319			`got_nodata++;`
320			`/* FALLTHROUGH */`
321			`case HOST_NOT_FOUND:`
322			`/* keep trying */`
323			`break;`
324			`case TRY_AGAIN:`
325			`if (hp->rcode == SERVFAIL) {`
326			`/* try next search element, if any */`
327			`got_servfail++;`
328			`break;`
329			`}`
330			`/* FALLTHROUGH */`
331			`default:`
332			`/* anything else implies that we're done */`
333			`done++;`
334			`}`
335
336			`/* if we got here for some reason other than DNSRCH,`
337			`* we only wanted one iteration of the loop, so stop.`
338			`*/`
339			`if ((statp->options & RES_DNSRCH) == 0)`
340			`done++;`
341			`}`
342			`}`
343
344			`/*`
345			`* If the name has any dots at all, and no earlier 'as-is' query`
346			`* for the name, and "." is not on the search list, then try an as-is`
347			`* query now.`
348			`*/`
349			`if (dots && !(tried_as_is \|\| root_on_list)) {`
350			`ret = __libc_res_nquerydomain(statp, name, NULL, class, type,`
351			`answer, anslen, answerp);`
352			`if (ret > 0)`
353			`return (ret);`
354			`}`
355
356			`/* if we got here, we didn't satisfy the search.`
357			`* if we did an initial full query, return that query's H_ERRNO`
358			`* (note that we wouldn't be here if that query had succeeded).`
359			`* else if we ever got a nodata, send that back as the reason.`
360			`* else send back meaningless H_ERRNO, that being the one from`
361			`* the last DNSRCH we did.`
362			`*/`
363			`if (saved_herrno != -1)`
364			`RES_SET_H_ERRNO(statp, saved_herrno);`
365			`else if (got_nodata)`
366			`RES_SET_H_ERRNO(statp, NO_DATA);`
367			`else if (got_servfail)`
368			`RES_SET_H_ERRNO(statp, TRY_AGAIN);`
369			`return (-1);`
370			`}`
371			`libresolv_hidden_def (__libc_res_nsearch)`
372
373			`int`
374			`res_nsearch(res_state statp,`
375			`const char name, / domain name */`
376			`int class, int type, /* class and type of query */`
377			`u_char answer, / buffer to put answer */`
378			`int anslen) /* size of answer */`
379			`{`
380			`return __libc_res_nsearch(statp, name, class, type, answer,`
381			`anslen, NULL);`
382			`}`
383			`libresolv_hidden_def (res_nsearch)`
384
385			`/*`
386			`* Perform a call on res_query on the concatenation of name and domain,`
387			`* removing a trailing dot from name if domain is NULL.`
388			`*/`
389			`static int`
390			`__libc_res_nquerydomain(res_state statp,`
391			`const char *name,`
392			`const char *domain,`
393			`int class, int type, /* class and type of query */`
394			`u_char answer, / buffer to put answer */`
395			`int anslen, /* size of answer */`
396			`u_char **answerp)`
397			`{`
398			`char nbuf[MAXDNAME];`
399			`const char *longname = nbuf;`
400			`int n, d;`
401
402			`#ifdef DEBUG`
403			`if (statp->options & RES_DEBUG)`
404			`printf(";; res_nquerydomain(%s, %s, %d, %d)\n",`
405			`name, domain?domain:"<Nil>", class, type);`
406			`#endif`
407			`if (domain == NULL) {`
408			`/*`
409			`* Check for trailing '.';`
410			`* copy without '.' if present.`
411			`*/`
412			`n = strlen(name);`
413			`if (n >= MAXDNAME) {`
414			`RES_SET_H_ERRNO(statp, NO_RECOVERY);`
415			`return (-1);`
416			`}`
417			`n--;`
418			`if (n >= 0 && name[n] == '.') {`
419			`strncpy(nbuf, name, n);`
420			`nbuf[n] = '\0';`
421			`} else`
422			`longname = name;`
423			`} else {`
424			`n = strlen(name);`
425			`d = strlen(domain);`
426			`if (n + d + 1 >= MAXDNAME) {`
427			`RES_SET_H_ERRNO(statp, NO_RECOVERY);`
428			`return (-1);`
429			`}`
430			`sprintf(nbuf, "%s.%s", name, domain);`
431			`}`
432			`return (__libc_res_nquery(statp, longname, class, type, answer,`
433			`anslen, answerp));`
434			`}`
435
436			`int`
437			`res_nquerydomain(res_state statp,`
438			`const char *name,`
439			`const char *domain,`
440			`int class, int type, /* class and type of query */`
441			`u_char answer, / buffer to put answer */`
442			`int anslen) /* size of answer */`
443			`{`
444			`return __libc_res_nquerydomain(statp, name, domain, class, type,`
445			`answer, anslen, NULL);`
446			`}`
447			`libresolv_hidden_def (res_nquerydomain)`
448
449			`const char *`
450			`res_hostalias(const res_state statp, const char name, char dst, size_t siz) {`
451			`char file, cp1, *cp2;`
452			`char buf[BUFSIZ];`
453			`FILE *fp;`
454
455			`if (statp->options & RES_NOALIASES)`
456			`return (NULL);`
457			`file = getenv("HOSTALIASES");`
458			`if (file == NULL \|\| (fp = fopen(file, "r")) == NULL)`
459			`return (NULL);`
460			`setbuf(fp, NULL);`
461			`buf[sizeof(buf) - 1] = '\0';`
462			`while (fgets(buf, sizeof(buf), fp)) {`
463			`for (cp1 = buf; cp1 && !isspace(cp1); ++cp1)`
464			`;`
465			`if (!*cp1)`
466			`break;`
467			`*cp1 = '\0';`
468			`if (ns_samename(buf, name) == 1) {`
469			`while (isspace(*++cp1))`
470			`;`
471			`if (!*cp1)`
472			`break;`
473			`for (cp2 = cp1 + 1; cp2 && !isspace(cp2); ++cp2)`
474			`;`
475			`*cp2 = '\0';`
476			`strncpy(dst, cp1, siz - 1);`
477			`dst[siz - 1] = '\0';`
478			`fclose(fp);`
479			`return (dst);`
480			`}`
481			`}`
482			`fclose(fp);`
483			`return (NULL);`
484			`}`
485			`libresolv_hidden_def (res_hostalias)`