1 files changed, 157 insertions, 0 deletions
diff --git a/libc/dns/resolv/res_data.cpp b/libc/dns/resolv/res_data.cpp
new file mode 100644
index 000000000..22d9f7b16
--- /dev/null
+++ b/libc/dns/resolv/res_data.cpp
@@ -0,0 +1,157 @@
+/*  $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;
+}