/* $NetBSD: gen_ho.c,v 1.1.1.2 2012/09/09 16:07:54 christos Exp $ */ /* * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") * 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 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. */ #if defined(LIBC_SCCS) && !defined(lint) static const char rcsid[] = "Id: gen_ho.c,v 1.5 2006/03/09 23:57:56 marka Exp "; #endif /* LIBC_SCCS and not lint */ /* Imports */ #include "port_before.h" #include #include #include #include #include #include #include #include #include #include #include #include "port_after.h" #include "irs_p.h" #include "gen_p.h" /* Definitions */ struct pvt { struct irs_rule * rules; struct irs_rule * rule; struct irs_ho * ho; struct __res_state * res; void (*free_res)(void *); }; /* Forwards */ static void ho_close(struct irs_ho *this); static struct hostent * ho_byname(struct irs_ho *this, const char *name); static struct hostent * ho_byname2(struct irs_ho *this, const char *name, int af); static struct hostent * ho_byaddr(struct irs_ho *this, const void *addr, int len, int af); static struct hostent * ho_next(struct irs_ho *this); static void ho_rewind(struct irs_ho *this); static void ho_minimize(struct irs_ho *this); static struct __res_state * ho_res_get(struct irs_ho *this); static void ho_res_set(struct irs_ho *this, struct __res_state *res, void (*free_res)(void *)); static struct addrinfo * ho_addrinfo(struct irs_ho *this, const char *name, const struct addrinfo *pai); static int init(struct irs_ho *this); /* Exports */ struct irs_ho * irs_gen_ho(struct irs_acc *this) { struct gen_p *accpvt = (struct gen_p *)this->private; struct irs_ho *ho; struct pvt *pvt; if (!(pvt = memget(sizeof *pvt))) { errno = ENOMEM; return (NULL); } memset(pvt, 0, sizeof *pvt); if (!(ho = memget(sizeof *ho))) { memput(pvt, sizeof *pvt); errno = ENOMEM; return (NULL); } memset(ho, 0x5e, sizeof *ho); pvt->rules = accpvt->map_rules[irs_ho]; pvt->rule = pvt->rules; ho->private = pvt; ho->close = ho_close; ho->byname = ho_byname; ho->byname2 = ho_byname2; ho->byaddr = ho_byaddr; ho->next = ho_next; ho->rewind = ho_rewind; ho->minimize = ho_minimize; ho->res_get = ho_res_get; ho->res_set = ho_res_set; ho->addrinfo = ho_addrinfo; return (ho); } /* Methods. */ static void ho_close(struct irs_ho *this) { struct pvt *pvt = (struct pvt *)this->private; ho_minimize(this); if (pvt->res && pvt->free_res) (*pvt->free_res)(pvt->res); memput(pvt, sizeof *pvt); memput(this, sizeof *this); } static struct hostent * ho_byname(struct irs_ho *this, const char *name) { struct pvt *pvt = (struct pvt *)this->private; struct irs_rule *rule; struct hostent *rval; struct irs_ho *ho; int therrno = NETDB_INTERNAL; int softerror = 0; if (init(this) == -1) return (NULL); for (rule = pvt->rules; rule; rule = rule->next) { ho = rule->inst->ho; RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL); errno = 0; rval = (*ho->byname)(ho, name); if (rval != NULL) return (rval); if (softerror == 0 && pvt->res->res_h_errno != HOST_NOT_FOUND && pvt->res->res_h_errno != NETDB_INTERNAL) { softerror = 1; therrno = pvt->res->res_h_errno; } if (rule->flags & IRS_CONTINUE) continue; /* * The value TRY_AGAIN can mean that the service * is not available, or just that this particular name * cannot be resolved now. We use the errno ECONNREFUSED * to distinguish. If a lookup sets that errno when * H_ERRNO is TRY_AGAIN, we continue to try other lookup * functions, otherwise we return the TRY_AGAIN error. */ if (pvt->res->res_h_errno != TRY_AGAIN || errno != ECONNREFUSED) break; } if (softerror != 0 && pvt->res->res_h_errno == HOST_NOT_FOUND) RES_SET_H_ERRNO(pvt->res, therrno); return (NULL); } static struct hostent * ho_byname2(struct irs_ho *this, const char *name, int af) { struct pvt *pvt = (struct pvt *)this->private; struct irs_rule *rule; struct hostent *rval; struct irs_ho *ho; int therrno = NETDB_INTERNAL; int softerror = 0; if (init(this) == -1) return (NULL); for (rule = pvt->rules; rule; rule = rule->next) { ho = rule->inst->ho; RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL); errno = 0; rval = (*ho->byname2)(ho, name, af); if (rval != NULL) return (rval); if (softerror == 0 && pvt->res->res_h_errno != HOST_NOT_FOUND && pvt->res->res_h_errno != NETDB_INTERNAL) { softerror = 1; therrno = pvt->res->res_h_errno; } if (rule->flags & IRS_CONTINUE) continue; /* * See the comments in ho_byname() explaining * the interpretation of TRY_AGAIN and ECONNREFUSED. */ if (pvt->res->res_h_errno != TRY_AGAIN || errno != ECONNREFUSED) break; } if (softerror != 0 && pvt->res->res_h_errno == HOST_NOT_FOUND) RES_SET_H_ERRNO(pvt->res, therrno); return (NULL); } static struct hostent * ho_byaddr(struct irs_ho *this, const void *addr, int len, int af) { struct pvt *pvt = (struct pvt *)this->private; struct irs_rule *rule; struct hostent *rval; struct irs_ho *ho; int therrno = NETDB_INTERNAL; int softerror = 0; if (init(this) == -1) return (NULL); for (rule = pvt->rules; rule; rule = rule->next) { ho = rule->inst->ho; RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL); errno = 0; rval = (*ho->byaddr)(ho, addr, len, af); if (rval != NULL) return (rval); if (softerror == 0 && pvt->res->res_h_errno != HOST_NOT_FOUND && pvt->res->res_h_errno != NETDB_INTERNAL) { softerror = 1; therrno = pvt->res->res_h_errno; } if (rule->flags & IRS_CONTINUE) continue; /* * See the comments in ho_byname() explaining * the interpretation of TRY_AGAIN and ECONNREFUSED. */ if (pvt->res->res_h_errno != TRY_AGAIN || errno != ECONNREFUSED) break; } if (softerror != 0 && pvt->res->res_h_errno == HOST_NOT_FOUND) RES_SET_H_ERRNO(pvt->res, therrno); return (NULL); } static struct hostent * ho_next(struct irs_ho *this) { struct pvt *pvt = (struct pvt *)this->private; struct hostent *rval; struct irs_ho *ho; while (pvt->rule) { ho = pvt->rule->inst->ho; rval = (*ho->next)(ho); if (rval) return (rval); if (!(pvt->rule->flags & IRS_CONTINUE)) break; pvt->rule = pvt->rule->next; if (pvt->rule) { ho = pvt->rule->inst->ho; (*ho->rewind)(ho); } } return (NULL); } static void ho_rewind(struct irs_ho *this) { struct pvt *pvt = (struct pvt *)this->private; struct irs_ho *ho; pvt->rule = pvt->rules; if (pvt->rule) { ho = pvt->rule->inst->ho; (*ho->rewind)(ho); } } static void ho_minimize(struct irs_ho *this) { struct pvt *pvt = (struct pvt *)this->private; struct irs_rule *rule; if (pvt->res) res_nclose(pvt->res); for (rule = pvt->rules; rule != NULL; rule = rule->next) { struct irs_ho *ho = rule->inst->ho; (*ho->minimize)(ho); } } static struct __res_state * ho_res_get(struct irs_ho *this) { struct pvt *pvt = (struct pvt *)this->private; if (!pvt->res) { struct __res_state *res; res = (struct __res_state *)malloc(sizeof *res); if (!res) { errno = ENOMEM; return (NULL); } memset(res, 0, sizeof *res); ho_res_set(this, res, free); } return (pvt->res); } static void ho_res_set(struct irs_ho *this, struct __res_state *res, void (*free_res)(void *)) { struct pvt *pvt = (struct pvt *)this->private; struct irs_rule *rule; if (pvt->res && pvt->free_res) { res_nclose(pvt->res); (*pvt->free_res)(pvt->res); } pvt->res = res; pvt->free_res = free_res; for (rule = pvt->rules; rule != NULL; rule = rule->next) { struct irs_ho *ho = rule->inst->ho; (*ho->res_set)(ho, pvt->res, NULL); } } static struct addrinfo * ho_addrinfo(struct irs_ho *this, const char *name, const struct addrinfo *pai) { struct pvt *pvt = (struct pvt *)this->private; struct irs_rule *rule; struct addrinfo *rval = NULL; struct irs_ho *ho; int therrno = NETDB_INTERNAL; int softerror = 0; if (init(this) == -1) return (NULL); for (rule = pvt->rules; rule; rule = rule->next) { ho = rule->inst->ho; RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL); errno = 0; if (ho->addrinfo == NULL) /*%< for safety */ continue; rval = (*ho->addrinfo)(ho, name, pai); if (rval != NULL) return (rval); if (softerror == 0 && pvt->res->res_h_errno != HOST_NOT_FOUND && pvt->res->res_h_errno != NETDB_INTERNAL) { softerror = 1; therrno = pvt->res->res_h_errno; } if (rule->flags & IRS_CONTINUE) continue; /* * See the comments in ho_byname() explaining * the interpretation of TRY_AGAIN and ECONNREFUSED. */ if (pvt->res->res_h_errno != TRY_AGAIN || errno != ECONNREFUSED) break; } if (softerror != 0 && pvt->res->res_h_errno == HOST_NOT_FOUND) RES_SET_H_ERRNO(pvt->res, therrno); return (NULL); } static int init(struct irs_ho *this) { struct pvt *pvt = (struct pvt *)this->private; if (!pvt->res && !ho_res_get(this)) return (-1); if (((pvt->res->options & RES_INIT) == 0U) && (res_ninit(pvt->res) == -1)) return (-1); return (0); } /*! \file */