| /* $NetBSD: res_data.c,v 1.8 2004/06/09 18:07:03 christos Exp $ */ |
| |
| /* |
| * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") |
| * Copyright (c) 1995-1999 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. |
| */ |
| |
| #include "resolv_private.h" |
| |
| #include <pthread.h> |
| |
| extern "C" int res_ourserver_p(const res_state, const struct sockaddr*); |
| extern "C" int __res_vinit(res_state, int); |
| |
| class GlobalStateAccessor { |
| public: |
| GlobalStateAccessor() { |
| pthread_mutex_lock(&mutex); |
| if (!initialized) { |
| init(); |
| initialized = true; |
| } |
| } |
| |
| ~GlobalStateAccessor() { |
| pthread_mutex_unlock(&mutex); |
| } |
| |
| __res_state* get() { |
| return &state; |
| } |
| |
| int init(); |
| |
| private: |
| static __res_state state; |
| static bool initialized; |
| static pthread_mutex_t mutex; |
| }; |
| __res_state GlobalStateAccessor::state; |
| bool GlobalStateAccessor::initialized = false; |
| pthread_mutex_t GlobalStateAccessor::mutex = PTHREAD_MUTEX_INITIALIZER; |
| |
| int GlobalStateAccessor::init() { |
| // These three fields used to be statically initialized. This made |
| // it hard to use this code in a shared library. It is necessary, |
| // now that we're doing dynamic initialization here, that we preserve |
| // the old semantics: if an application modifies one of these three |
| // fields of _res before res_init() is called, res_init() will not |
| // alter them. Of course, if an application is setting them to |
| // _zero_ before calling res_init(), hoping to override what used |
| // to be the static default, we can't detect it and unexpected results |
| // will follow. Zero for any of these fields would make no sense, |
| // so one can safely assume that the applications were already getting |
| // unexpected results. |
| // g_nres.options is tricky since some apps were known to diddle the bits |
| // before res_init() was first called. We can't replicate that semantic |
| // with dynamic initialization (they may have turned bits off that are |
| // set in RES_DEFAULT). Our solution is to declare such applications |
| // "broken". They could fool us by setting RES_INIT but none do (yet). |
| if (!state.retrans) state.retrans = RES_TIMEOUT; |
| if (!state.retry) state.retry = 4; |
| if (!(state.options & RES_INIT)) state.options = RES_DEFAULT; |
| |
| // This one used to initialize implicitly to zero, so unless the app |
| // has set it to something in particular, we can randomize it now. |
| if (!state.id) state.id = res_randomid(); |
| |
| return __res_vinit(&state, 1); |
| } |
| |
| int res_init(void) { |
| GlobalStateAccessor gsa; |
| return gsa.init(); |
| } |
| |
| void p_query(const u_char* msg) { |
| fp_query(msg, stdout); |
| } |
| |
| void fp_query(const u_char* msg, FILE* file) { |
| fp_nquery(msg, PACKETSZ, file); |
| } |
| |
| void fp_nquery(const u_char* msg, int len, FILE* file) { |
| GlobalStateAccessor gsa; |
| res_pquery(gsa.get(), msg, len, file); |
| } |
| |
| int |
| res_mkquery(int op, const char* dname, int klass, int type, const u_char* data, |
| int datalen, const u_char* newrr_in, u_char* buf, int buflen) { |
| GlobalStateAccessor gsa; |
| return res_nmkquery(gsa.get(), op, dname, klass, type, data, datalen, newrr_in, buf, buflen); |
| } |
| |
| int res_query(const char* name, int klass, int type, u_char* answer, int anslen) { |
| GlobalStateAccessor gsa; |
| return res_nquery(gsa.get(), name, klass, type, answer, anslen); |
| } |
| |
| void res_send_setqhook(res_send_qhook hook) { |
| GlobalStateAccessor gsa; |
| gsa.get()->qhook = hook; |
| } |
| |
| void res_send_setrhook(res_send_rhook hook) { |
| GlobalStateAccessor gsa; |
| gsa.get()->rhook = hook; |
| } |
| |
| int res_isourserver(const struct sockaddr_in* inp) { |
| GlobalStateAccessor gsa; |
| return res_ourserver_p(gsa.get(), reinterpret_cast<const sockaddr*>(inp)); |
| } |
| |
| int res_send(const u_char* buf, int buflen, u_char* ans, int anssiz) { |
| GlobalStateAccessor gsa; |
| return res_nsend(gsa.get(), buf, buflen, ans, anssiz); |
| } |
| |
| void res_close(void) { |
| GlobalStateAccessor gsa; |
| res_nclose(gsa.get()); |
| } |
| |
| int res_search(const char* name, int klass, int type, u_char* answer, int anslen) { |
| GlobalStateAccessor gsa; |
| return res_nsearch(gsa.get(), name, klass, type, answer, anslen); |
| } |
| |
| int res_querydomain(const char* name, const char* domain, int klass, int type, u_char* answer, |
| int anslen) { |
| GlobalStateAccessor gsa; |
| return res_nquerydomain(gsa.get(), name, domain, klass, type, answer, anslen); |
| } |
| |
| int res_opt(int a, u_char* b, int c, int d) { |
| GlobalStateAccessor gsa; |
| return res_nopt(gsa.get(), a, b, c, d); |
| } |
| |
| const char* hostalias(const char* name) { |
| return NULL; |
| } |