Minimal changes to bring the resolver into the C++ era
It took surprisingly few changes, considering the leap from C with some
K&R constructs to C++17; most of the diffs are adding explicit pointer
casts and renaming variables called 'class' or 'try'.
As a result of building as C++, some of the names are now mangled,
making clashes with bionic harder. However, some names remain C due to
the __BEGIN_DECLS / __END_DECLS macros, scheduled to be removed in a
later cleanup pass.
Test: atest netd_integration_test
Change-Id: I3aefb9078421ec42f98f97d917785b365545feba
diff --git a/sethostent.cpp b/sethostent.cpp
new file mode 100644
index 0000000..5a7ab78
--- /dev/null
+++ b/sethostent.cpp
@@ -0,0 +1,232 @@
+/* $NetBSD: sethostent.c,v 1.20 2014/03/17 13:24:23 christos Exp $ */
+
+/*
+ * Copyright (c) 1985, 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.
+ * 3. 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.
+ */
+
+#include <arpa/inet.h>
+#include <arpa/nameser.h>
+#include <assert.h>
+#include <errno.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <nsswitch.h>
+#include <resolv.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/param.h>
+
+#include "hostent.h"
+#include "resolv_private.h"
+
+// NetBSD uses _DIAGASSERT to null-check arguments and the like,
+// but it's clear from the number of mistakes in their assertions
+// that they don't actually test or ship with this.
+#define _DIAGASSERT(e) /* nothing */
+
+#define ALIGNBYTES (sizeof(uintptr_t) - 1)
+#define ALIGN(p) (((uintptr_t)(p) + ALIGNBYTES) & ~ALIGNBYTES)
+
+static struct hostent* _hf_gethtbyname2(const char*, int, struct getnamaddr*);
+
+void
+sethostent(int /*stayopen*/) {
+ struct res_static* rs = __res_get_static();
+ if (rs) sethostent_r(&rs->hostf);
+}
+
+void endhostent(void) {
+ struct res_static* rs = __res_get_static();
+ if (rs) endhostent_r(&rs->hostf);
+}
+
+void sethostent_r(FILE** hf) {
+ if (!*hf)
+ *hf = fopen(_PATH_HOSTS, "re");
+ else
+ rewind(*hf);
+}
+
+void endhostent_r(FILE** hf) {
+ if (*hf) {
+ (void) fclose(*hf);
+ *hf = NULL;
+ }
+}
+
+int _hf_gethtbyname(void* rv, void* /*cb_data*/, va_list ap) {
+ struct hostent* hp;
+ const char* name;
+ int af;
+ struct getnamaddr* info = (struct getnamaddr*) rv;
+
+ _DIAGASSERT(rv != NULL);
+
+ name = va_arg(ap, char*);
+ /* NOSTRICT skip string len */ (void) va_arg(ap, int);
+ af = va_arg(ap, int);
+
+ hp = _hf_gethtbyname2(name, af, info);
+ if (hp == NULL) {
+ if (*info->he == NETDB_INTERNAL && errno == ENOSPC) {
+ return NS_UNAVAIL; // glibc compatibility.
+ }
+ *info->he = HOST_NOT_FOUND;
+ return NS_NOTFOUND;
+ }
+ return NS_SUCCESS;
+}
+
+struct hostent* _hf_gethtbyname2(const char* name, int af, struct getnamaddr* info) {
+ struct hostent *hp, hent;
+ char *buf, *ptr;
+ size_t len, anum, num, i;
+ FILE* hf;
+ char* aliases[MAXALIASES];
+ char* addr_ptrs[MAXADDRS];
+
+ _DIAGASSERT(name != NULL);
+
+ hf = NULL;
+ sethostent_r(&hf);
+ if (hf == NULL) {
+ errno = EINVAL;
+ *info->he = NETDB_INTERNAL;
+ return NULL;
+ }
+
+ if ((ptr = buf = (char*) malloc(len = info->buflen)) == NULL) {
+ *info->he = NETDB_INTERNAL;
+ return NULL;
+ }
+
+ anum = 0; /* XXX: gcc */
+ hent.h_name = NULL; /* XXX: gcc */
+ hent.h_addrtype = 0; /* XXX: gcc */
+ hent.h_length = 0; /* XXX: gcc */
+
+ for (num = 0; num < MAXADDRS;) {
+ info->hp->h_addrtype = af;
+ info->hp->h_length = 0;
+
+ hp = netbsd_gethostent_r(hf, info->hp, info->buf, info->buflen, info->he);
+ if (hp == NULL) {
+ if (*info->he == NETDB_INTERNAL && errno == ENOSPC) {
+ goto nospc; // glibc compatibility.
+ }
+ break;
+ }
+
+ if (strcasecmp(hp->h_name, name) != 0) {
+ char** cp;
+ for (cp = hp->h_aliases; *cp != NULL; cp++)
+ if (strcasecmp(*cp, name) == 0) break;
+ if (*cp == NULL) continue;
+ }
+
+ if (num == 0) {
+ hent.h_addrtype = af = hp->h_addrtype;
+ hent.h_length = hp->h_length;
+
+ HENT_SCOPY(hent.h_name, hp->h_name, ptr, len);
+ for (anum = 0; hp->h_aliases[anum]; anum++) {
+ if (anum >= MAXALIASES) goto nospc;
+ HENT_SCOPY(aliases[anum], hp->h_aliases[anum], ptr, len);
+ }
+ ptr = (char*) ALIGN(ptr);
+ if ((size_t)(ptr - buf) >= info->buflen) goto nospc;
+ }
+
+ if (num >= MAXADDRS) goto nospc;
+ HENT_COPY(addr_ptrs[num], hp->h_addr_list[0], hp->h_length, ptr, len);
+ num++;
+ }
+ endhostent_r(&hf);
+
+ if (num == 0) {
+ *info->he = HOST_NOT_FOUND;
+ free(buf);
+ return NULL;
+ }
+
+ hp = info->hp;
+ ptr = info->buf;
+ len = info->buflen;
+
+ hp->h_addrtype = hent.h_addrtype;
+ hp->h_length = hent.h_length;
+
+ HENT_ARRAY(hp->h_aliases, anum, ptr, len);
+ HENT_ARRAY(hp->h_addr_list, num, ptr, len);
+
+ for (i = 0; i < num; i++) HENT_COPY(hp->h_addr_list[i], addr_ptrs[i], hp->h_length, ptr, len);
+ hp->h_addr_list[num] = NULL;
+
+ HENT_SCOPY(hp->h_name, hent.h_name, ptr, len);
+
+ for (i = 0; i < anum; i++) HENT_SCOPY(hp->h_aliases[i], aliases[i], ptr, len);
+ hp->h_aliases[anum] = NULL;
+
+ free(buf);
+ return hp;
+nospc:
+ *info->he = NETDB_INTERNAL;
+ free(buf);
+ errno = ENOSPC;
+ return NULL;
+}
+
+int _hf_gethtbyaddr(void* rv, void* /*cb_data*/, va_list ap) {
+ struct hostent* hp;
+ const unsigned char* addr;
+ struct getnamaddr* info = (struct getnamaddr*) rv;
+ FILE* hf;
+
+ _DIAGASSERT(rv != NULL);
+
+ addr = va_arg(ap, unsigned char*);
+ info->hp->h_length = va_arg(ap, int);
+ info->hp->h_addrtype = va_arg(ap, int);
+
+ hf = NULL;
+ sethostent_r(&hf);
+ if (hf == NULL) {
+ *info->he = NETDB_INTERNAL;
+ return NS_UNAVAIL;
+ }
+ while ((hp = netbsd_gethostent_r(hf, info->hp, info->buf, info->buflen, info->he)) != NULL)
+ if (!memcmp(hp->h_addr_list[0], addr, (size_t) hp->h_length)) break;
+ endhostent_r(&hf);
+
+ if (hp == NULL) {
+ if (errno == ENOSPC) return NS_UNAVAIL; // glibc compatibility.
+ *info->he = HOST_NOT_FOUND;
+ return NS_NOTFOUND;
+ }
+ return NS_SUCCESS;
+}