Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 595 insertions, 0 deletions

diff --git a/src/c-ares/test/ares-test-init.cc b/src/c-ares/test/ares-test-init.cc
new file mode 100644
index 000000000..66570ace5
--- /dev/null
+++ b/src/c-ares/test/ares-test-init.cc
@@ -0,0 +1,595 @@
+#include "ares-test.h"
+
+// library initialization is only needed for windows builds
+#ifdef WIN32
+#define EXPECTED_NONINIT ARES_ENOTINITIALIZED
+#else
+#define EXPECTED_NONINIT ARES_SUCCESS
+#endif
+
+namespace ares {
+namespace test {
+
+TEST(LibraryInit, Basic) {
+  EXPECT_EQ(EXPECTED_NONINIT, ares_library_initialized());
+  EXPECT_EQ(ARES_SUCCESS, ares_library_init(ARES_LIB_INIT_ALL));
+  EXPECT_EQ(ARES_SUCCESS, ares_library_initialized());
+  ares_library_cleanup();
+  EXPECT_EQ(EXPECTED_NONINIT, ares_library_initialized());
+}
+
+TEST(LibraryInit, UnexpectedCleanup) {
+  EXPECT_EQ(EXPECTED_NONINIT, ares_library_initialized());
+  ares_library_cleanup();
+  EXPECT_EQ(EXPECTED_NONINIT, ares_library_initialized());
+}
+
+TEST(LibraryInit, DISABLED_InvalidParam) {
+  // TODO: police flags argument to ares_library_init()
+  EXPECT_EQ(ARES_EBADQUERY, ares_library_init(ARES_LIB_INIT_ALL << 2));
+  EXPECT_EQ(EXPECTED_NONINIT, ares_library_initialized());
+  ares_library_cleanup();
+}
+
+TEST(LibraryInit, Nested) {
+  EXPECT_EQ(EXPECTED_NONINIT, ares_library_initialized());
+  EXPECT_EQ(ARES_SUCCESS, ares_library_init(ARES_LIB_INIT_ALL));
+  EXPECT_EQ(ARES_SUCCESS, ares_library_initialized());
+  EXPECT_EQ(ARES_SUCCESS, ares_library_init(ARES_LIB_INIT_ALL));
+  EXPECT_EQ(ARES_SUCCESS, ares_library_initialized());
+  ares_library_cleanup();
+  EXPECT_EQ(ARES_SUCCESS, ares_library_initialized());
+  ares_library_cleanup();
+  EXPECT_EQ(EXPECTED_NONINIT, ares_library_initialized());
+}
+
+TEST(LibraryInit, BasicChannelInit) {
+  EXPECT_EQ(ARES_SUCCESS, ares_library_init(ARES_LIB_INIT_ALL));
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+  EXPECT_NE(nullptr, channel);
+  ares_destroy(channel);
+  ares_library_cleanup();
+}
+
+TEST_F(LibraryTest, OptionsChannelInit) {
+  struct ares_options opts = {0};
+  int optmask = 0;
+  opts.flags = ARES_FLAG_USEVC | ARES_FLAG_PRIMARY;
+  optmask |= ARES_OPT_FLAGS;
+  opts.timeout = 2000;
+  optmask |= ARES_OPT_TIMEOUTMS;
+  opts.tries = 2;
+  optmask |= ARES_OPT_TRIES;
+  opts.ndots = 4;
+  optmask |= ARES_OPT_NDOTS;
+  opts.udp_port = 54;
+  optmask |= ARES_OPT_UDP_PORT;
+  opts.tcp_port = 54;
+  optmask |= ARES_OPT_TCP_PORT;
+  opts.socket_send_buffer_size = 514;
+  optmask |= ARES_OPT_SOCK_SNDBUF;
+  opts.socket_receive_buffer_size = 514;
+  optmask |= ARES_OPT_SOCK_RCVBUF;
+  opts.ednspsz = 1280;
+  optmask |= ARES_OPT_EDNSPSZ;
+  opts.nservers = 2;
+  opts.servers = (struct in_addr *)malloc(opts.nservers * sizeof(struct in_addr));
+  opts.servers[0].s_addr = htonl(0x01020304);
+  opts.servers[1].s_addr = htonl(0x02030405);
+  optmask |= ARES_OPT_SERVERS;
+  opts.ndomains = 2;
+  opts.domains = (char **)malloc(opts.ndomains * sizeof(char *));
+  opts.domains[0] = strdup("example.com");
+  opts.domains[1] = strdup("example2.com");
+  optmask |= ARES_OPT_DOMAINS;
+  opts.lookups = strdup("b");
+  optmask |= ARES_OPT_LOOKUPS;
+  optmask |= ARES_OPT_ROTATE;
+
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init_options(&channel, &opts, optmask));
+  EXPECT_NE(nullptr, channel);
+
+  ares_channel channel2 = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_dup(&channel2, channel));
+
+  struct ares_options opts2 = {0};
+  int optmask2 = 0;
+  EXPECT_EQ(ARES_SUCCESS, ares_save_options(channel2, &opts2, &optmask2));
+
+  // Note that not all opts-settable fields are saved (e.g.
+  // ednspsz, socket_{send,receive}_buffer_size).
+  EXPECT_EQ(opts.flags, opts2.flags);
+  EXPECT_EQ(opts.timeout, opts2.timeout);
+  EXPECT_EQ(opts.tries, opts2.tries);
+  EXPECT_EQ(opts.ndots, opts2.ndots);
+  EXPECT_EQ(opts.udp_port, opts2.udp_port);
+  EXPECT_EQ(opts.tcp_port, opts2.tcp_port);
+  EXPECT_EQ(1, opts2.nservers);  // Truncated by ARES_FLAG_PRIMARY
+  EXPECT_EQ(opts.servers[0].s_addr, opts2.servers[0].s_addr);
+  EXPECT_EQ(opts.ndomains, opts2.ndomains);
+  EXPECT_EQ(std::string(opts.domains[0]), std::string(opts2.domains[0]));
+  EXPECT_EQ(std::string(opts.domains[1]), std::string(opts2.domains[1]));
+  EXPECT_EQ(std::string(opts.lookups), std::string(opts2.lookups));
+
+  ares_destroy_options(&opts);
+  ares_destroy_options(&opts2);
+  ares_destroy(channel);
+  ares_destroy(channel2);
+}
+
+TEST_F(LibraryTest, ChannelAllocFail) {
+  ares_channel channel;
+  for (int ii = 1; ii <= 25; ii++) {
+    ClearFails();
+    SetAllocFail(ii);
+    channel = nullptr;
+    int rc = ares_init(&channel);
+    // The number of allocations depends on local environment, so don't expect ENOMEM.
+    if (rc == ARES_ENOMEM) {
+      EXPECT_EQ(nullptr, channel);
+    } else {
+      ares_destroy(channel);
+    }
+  }
+}
+
+TEST_F(LibraryTest, OptionsChannelAllocFail) {
+  struct ares_options opts = {0};
+  int optmask = 0;
+  opts.flags = ARES_FLAG_USEVC;
+  optmask |= ARES_OPT_FLAGS;
+  opts.timeout = 2;
+  optmask |= ARES_OPT_TIMEOUT;
+  opts.tries = 2;
+  optmask |= ARES_OPT_TRIES;
+  opts.ndots = 4;
+  optmask |= ARES_OPT_NDOTS;
+  opts.udp_port = 54;
+  optmask |= ARES_OPT_UDP_PORT;
+  opts.tcp_port = 54;
+  optmask |= ARES_OPT_TCP_PORT;
+  opts.socket_send_buffer_size = 514;
+  optmask |= ARES_OPT_SOCK_SNDBUF;
+  opts.socket_receive_buffer_size = 514;
+  optmask |= ARES_OPT_SOCK_RCVBUF;
+  opts.ednspsz = 1280;
+  optmask |= ARES_OPT_EDNSPSZ;
+  opts.nservers = 2;
+  opts.servers = (struct in_addr *)malloc(opts.nservers * sizeof(struct in_addr));
+  opts.servers[0].s_addr = htonl(0x01020304);
+  opts.servers[1].s_addr = htonl(0x02030405);
+  optmask |= ARES_OPT_SERVERS;
+  opts.ndomains = 2;
+  opts.domains = (char **)malloc(opts.ndomains * sizeof(char *));
+  opts.domains[0] = strdup("example.com");
+  opts.domains[1] = strdup("example2.com");
+  optmask |= ARES_OPT_DOMAINS;
+  opts.lookups = strdup("b");
+  optmask |= ARES_OPT_LOOKUPS;
+  optmask |= ARES_OPT_ROTATE;
+
+  ares_channel channel = nullptr;
+  for (int ii = 1; ii <= 8; ii++) {
+    ClearFails();
+    SetAllocFail(ii);
+    int rc = ares_init_options(&channel, &opts, optmask);
+    if (rc == ARES_ENOMEM) {
+      EXPECT_EQ(nullptr, channel);
+    } else {
+      EXPECT_EQ(ARES_SUCCESS, rc);
+      ares_destroy(channel);
+      channel = nullptr;
+    }
+  }
+  ClearFails();
+
+  EXPECT_EQ(ARES_SUCCESS, ares_init_options(&channel, &opts, optmask));
+  EXPECT_NE(nullptr, channel);
+
+  // Add some servers and a sortlist for flavour.
+  EXPECT_EQ(ARES_SUCCESS,
+            ares_set_servers_csv(channel, "1.2.3.4,0102:0304:0506:0708:0910:1112:1314:1516,2.3.4.5"));
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel, "1.2.3.4 2.3.4.5"));
+
+  ares_channel channel2 = nullptr;
+  for (int ii = 1; ii <= 18; ii++) {
+    ClearFails();
+    SetAllocFail(ii);
+    EXPECT_EQ(ARES_ENOMEM, ares_dup(&channel2, channel)) << ii;
+    EXPECT_EQ(nullptr, channel2) << ii;
+  }
+
+  struct ares_options opts2;
+  int optmask2 = 0;
+  for (int ii = 1; ii <= 6; ii++) {
+    memset(&opts2, 0, sizeof(opts2));
+    ClearFails();
+    SetAllocFail(ii);
+    EXPECT_EQ(ARES_ENOMEM, ares_save_options(channel, &opts2, &optmask2)) << ii;
+    // May still have allocations even after ARES_ENOMEM return code.
+    ares_destroy_options(&opts2);
+  }
+  ares_destroy_options(&opts);
+  ares_destroy(channel);
+}
+
+TEST_F(LibraryTest, FailChannelInit) {
+  EXPECT_EQ(ARES_SUCCESS,
+            ares_library_init_mem(ARES_LIB_INIT_ALL,
+                                  &LibraryTest::amalloc,
+                                  &LibraryTest::afree,
+                                  &LibraryTest::arealloc));
+  SetAllocFail(1);
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_ENOMEM, ares_init(&channel));
+  EXPECT_EQ(nullptr, channel);
+  ares_library_cleanup();
+}
+
+#ifndef WIN32
+TEST_F(LibraryTest, EnvInit) {
+  ares_channel channel = nullptr;
+  EnvValue v1("LOCALDOMAIN", "this.is.local");
+  EnvValue v2("RES_OPTIONS", "options debug ndots:3 retry:3 rotate retrans:2");
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+  ares_destroy(channel);
+}
+
+TEST_F(LibraryTest, EnvInitAllocFail) {
+  ares_channel channel;
+  EnvValue v1("LOCALDOMAIN", "this.is.local");
+  EnvValue v2("RES_OPTIONS", "options debug ndots:3 retry:3 rotate retrans:2");
+  for (int ii = 1; ii <= 10; ii++) {
+    ClearFails();
+    SetAllocFail(ii);
+    channel = nullptr;
+    int rc = ares_init(&channel);
+    if (rc == ARES_SUCCESS) {
+      ares_destroy(channel);
+    } else {
+      EXPECT_EQ(ARES_ENOMEM, rc);
+    }
+  }
+}
+#endif
+
+TEST_F(DefaultChannelTest, SetAddresses) {
+  ares_set_local_ip4(channel_, 0x01020304);
+  byte addr6[16] = {0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
+                    0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10};
+  ares_set_local_ip6(channel_, addr6);
+  ares_set_local_dev(channel_, "dummy");
+}
+
+TEST_F(DefaultChannelTest, SetSortlistFailures) {
+  EXPECT_EQ(ARES_ENODATA, ares_set_sortlist(nullptr, "1.2.3.4"));
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "xyzzy ; lwk"));
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "xyzzy ; 0x123"));
+}
+
+TEST_F(DefaultChannelTest, SetSortlistVariants) {
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "1.2.3.4"));
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "1.2.3.4 ; 2.3.4.5"));
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "129.1.1.1"));
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "192.1.1.1"));
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "224.1.1.1"));
+  EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "225.1.1.1"));
+}
+
+TEST_F(DefaultChannelTest, SetSortlistAllocFail) {
+  for (int ii = 1; ii <= 3; ii++) {
+    ClearFails();
+    SetAllocFail(ii);
+    EXPECT_EQ(ARES_ENOMEM, ares_set_sortlist(channel_, "12.13.0.0/16 1234::5678/40 1.2.3.4")) << ii;
+  }
+}
+
+#ifdef USE_WINSOCK
+TEST(Init, NoLibraryInit) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_ENOTINITIALIZED, ares_init(&channel));
+}
+#endif
+
+#ifdef HAVE_CONTAINER
+// These tests rely on the ability of non-root users to create a chroot
+// using Linux namespaces.
+
+
+// The library uses a variety of information sources to initialize a channel,
+// in particular to determine:
+//  - search: the search domains to use
+//  - servers: the name servers to use
+//  - lookup: whether to check files or DNS or both (e.g. "fb")
+//  - options: various resolver options
+//  - sortlist: the order of preference for IP addresses
+//
+// The first source from the following list is used:
+//  - init_by_options(): explicitly specified values in struct ares_options
+//  - init_by_environment(): values from the environment:
+//     - LOCALDOMAIN -> search (single value)
+//     - RES_OPTIONS -> options
+//  - init_by_resolv_conf(): values from various config files:
+//     - /etc/resolv.conf -> search, lookup, servers, sortlist, options
+//     - /etc/nsswitch.conf -> lookup
+//     - /etc/host.conf -> lookup
+//     - /etc/svc.conf -> lookup
+//  - init_by_defaults(): fallback values:
+//     - gethostname(3) -> domain
+//     - "fb" -> lookup
+
+NameContentList filelist = {
+  {"/etc/resolv.conf", "nameserver 1.2.3.4\n"
+                       "sortlist 1.2.3.4/16 2.3.4.5\n"
+                       "search first.com second.com\n"},
+  {"/etc/hosts", "3.4.5.6 ahostname.com\n"},
+  {"/etc/nsswitch.conf", "hosts: files\n"}};
+CONTAINED_TEST_F(LibraryTest, ContainerChannelInit,
+                 "myhostname", "mydomainname.org", filelist) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+  std::vector<std::string> actual = GetNameServers(channel);
+  std::vector<std::string> expected = {"1.2.3.4"};
+  EXPECT_EQ(expected, actual);
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(2, opts.ndomains);
+  EXPECT_EQ(std::string("first.com"), std::string(opts.domains[0]));
+  EXPECT_EQ(std::string("second.com"), std::string(opts.domains[1]));
+  ares_destroy_options(&opts);
+
+  HostResult result;
+  ares_gethostbyname(channel, "ahostname.com", AF_INET, HostCallback, &result);
+  ProcessWork(channel, NoExtraFDs, nullptr);
+  EXPECT_TRUE(result.done_);
+  std::stringstream ss;
+  ss << result.host_;
+  EXPECT_EQ("{'ahostname.com' aliases=[] addrs=[3.4.5.6]}", ss.str());
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+CONTAINED_TEST_F(LibraryTest, ContainerSortlistOptionInit,
+                 "myhostname", "mydomainname.org", filelist) {
+  ares_channel channel = nullptr;
+  struct ares_options opts = {0};
+  int optmask = 0;
+  optmask |= ARES_OPT_SORTLIST;
+  opts.nsort = 0;
+  // Explicitly specifying an empty sortlist in the options should override the
+  // environment.
+  EXPECT_EQ(ARES_SUCCESS, ares_init_options(&channel, &opts, optmask));
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(0, opts.nsort);
+  EXPECT_EQ(nullptr, opts.sortlist);
+  EXPECT_EQ(ARES_OPT_SORTLIST, (optmask & ARES_OPT_SORTLIST));
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+NameContentList fullresolv = {
+  {"/etc/resolv.conf", " nameserver   1.2.3.4 \n"
+                       "search   first.com second.com\n"
+                       "lookup bind\n"
+                       "options debug ndots:5\n"
+                       "sortlist 1.2.3.4/16 2.3.4.5\n"}};
+CONTAINED_TEST_F(LibraryTest, ContainerFullResolvInit,
+                 "myhostname", "mydomainname.org", fullresolv) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(std::string("b"), std::string(opts.lookups));
+  EXPECT_EQ(5, opts.ndots);
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+NameContentList hostconf = {
+  {"/etc/resolv.conf", "nameserver 1.2.3.4\n"
+                       "sortlist1.2.3.4\n"  // malformed line
+                       "search first.com second.com\n"},
+  {"/etc/host.conf", "order bind hosts\n"}};
+CONTAINED_TEST_F(LibraryTest, ContainerHostConfInit,
+                 "myhostname", "mydomainname.org", hostconf) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(std::string("bf"), std::string(opts.lookups));
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+NameContentList svcconf = {
+  {"/etc/resolv.conf", "nameserver 1.2.3.4\n"
+                       "search first.com second.com\n"},
+  {"/etc/svc.conf", "hosts= bind\n"}};
+CONTAINED_TEST_F(LibraryTest, ContainerSvcConfInit,
+                 "myhostname", "mydomainname.org", svcconf) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(std::string("b"), std::string(opts.lookups));
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+// Failures when expected config filenames are inaccessible.
+class MakeUnreadable {
+ public:
+  explicit MakeUnreadable(const std::string& filename)
+    : filename_(filename) {
+    chmod(filename_.c_str(), 0000);
+  }
+  ~MakeUnreadable() { chmod(filename_.c_str(), 0644); }
+ private:
+  std::string filename_;
+};
+
+CONTAINED_TEST_F(LibraryTest, ContainerResolvConfNotReadable,
+                 "myhostname", "mydomainname.org", filelist) {
+  ares_channel channel = nullptr;
+  MakeUnreadable hide("/etc/resolv.conf");
+  // Unavailable /etc/resolv.conf falls back to defaults
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+  return HasFailure();
+}
+CONTAINED_TEST_F(LibraryTest, ContainerNsswitchConfNotReadable,
+                 "myhostname", "mydomainname.org", filelist) {
+  ares_channel channel = nullptr;
+  // Unavailable /etc/nsswitch.conf falls back to defaults.
+  MakeUnreadable hide("/etc/nsswitch.conf");
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(std::string("fb"), std::string(opts.lookups));
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+CONTAINED_TEST_F(LibraryTest, ContainerHostConfNotReadable,
+                 "myhostname", "mydomainname.org", hostconf) {
+  ares_channel channel = nullptr;
+  // Unavailable /etc/host.conf falls back to defaults.
+  MakeUnreadable hide("/etc/host.conf");
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+  ares_destroy(channel);
+  return HasFailure();
+}
+CONTAINED_TEST_F(LibraryTest, ContainerSvcConfNotReadable,
+                 "myhostname", "mydomainname.org", svcconf) {
+  ares_channel channel = nullptr;
+  // Unavailable /etc/svc.conf falls back to defaults.
+  MakeUnreadable hide("/etc/svc.conf");
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+NameContentList rotateenv = {
+  {"/etc/resolv.conf", "nameserver 1.2.3.4\n"
+                       "search first.com second.com\n"
+                       "options rotate\n"}};
+CONTAINED_TEST_F(LibraryTest, ContainerRotateInit,
+                 "myhostname", "mydomainname.org", rotateenv) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(ARES_OPT_ROTATE, (optmask & ARES_OPT_ROTATE));
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+CONTAINED_TEST_F(LibraryTest, ContainerRotateOverride,
+                 "myhostname", "mydomainname.org", rotateenv) {
+  ares_channel channel = nullptr;
+  struct ares_options opts = {0};
+  int optmask = ARES_OPT_NOROTATE;
+  EXPECT_EQ(ARES_SUCCESS, ares_init_options(&channel, &opts, optmask));
+
+  optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(ARES_OPT_NOROTATE, (optmask & ARES_OPT_NOROTATE));
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+NameContentList multiresolv = {
+  {"/etc/resolv.conf", " nameserver 1::2 ;  ;;\n"
+                       " domain first.com\n"},
+  {"/etc/nsswitch.conf", "hosts: files\n"}};
+CONTAINED_TEST_F(LibraryTest, ContainerMultiResolvInit,
+                 "myhostname", "mydomainname.org", multiresolv) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+  std::vector<std::string> actual = GetNameServers(channel);
+  std::vector<std::string> expected = {"0001:0000:0000:0000:0000:0000:0000:0002"};
+  EXPECT_EQ(expected, actual);
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(1, opts.ndomains);
+  EXPECT_EQ(std::string("first.com"), std::string(opts.domains[0]));
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+NameContentList systemdresolv = {
+  {"/etc/resolv.conf", "nameserver 1.2.3.4\n"
+                       "domain first.com\n"},
+  {"/etc/nsswitch.conf", "hosts: junk resolve files\n"}};
+CONTAINED_TEST_F(LibraryTest, ContainerSystemdResolvInit,
+                 "myhostname", "mydomainname.org", systemdresolv) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(std::string("bf"), std::string(opts.lookups));
+  ares_destroy_options(&opts);
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+NameContentList empty = {};  // no files
+CONTAINED_TEST_F(LibraryTest, ContainerEmptyInit,
+                 "host.domain.org", "domain.org", empty) {
+  ares_channel channel = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_init(&channel));
+  std::vector<std::string> actual = GetNameServers(channel);
+  std::vector<std::string> expected = {"127.0.0.1"};
+  EXPECT_EQ(expected, actual);
+
+  struct ares_options opts;
+  int optmask = 0;
+  ares_save_options(channel, &opts, &optmask);
+  EXPECT_EQ(1, opts.ndomains);
+  EXPECT_EQ(std::string("domain.org"), std::string(opts.domains[0]));
+  EXPECT_EQ(std::string("fb"), std::string(opts.lookups));
+  ares_destroy_options(&opts);
+
+
+  ares_destroy(channel);
+  return HasFailure();
+}
+
+#endif
+
+}  // namespace test
+}  // namespace ares