1 #include "ares-test.h"
2 #include "dns-proto.h"
3
4 // Include ares internal files for DNS protocol details
5 #include "nameser.h"
6 #include "ares_dns.h"
7
8 #ifdef HAVE_NETDB_H
9 #include <netdb.h>
10 #endif
11 #ifdef HAVE_NETINET_TCP_H
12 #include <netinet/tcp.h>
13 #endif
14 #include <stdio.h>
15 #include <stdlib.h>
16
17 #include <functional>
18 #include <sstream>
19
20 #ifdef WIN32
21 #define BYTE_CAST (char *)
22 #define mkdir_(d, p) mkdir(d)
23 #else
24 #define BYTE_CAST
25 #define mkdir_(d, p) mkdir(d, p)
26 #endif
27
28 namespace ares {
29 namespace test {
30
31 bool verbose = false;
32 int mock_port = 5300;
33
34 const std::vector<int> both_families = {AF_INET, AF_INET6};
35 const std::vector<int> ipv4_family = {AF_INET};
36 const std::vector<int> ipv6_family = {AF_INET6};
37
38 const std::vector<std::pair<int, bool>> both_families_both_modes = {
39 std::make_pair<int, bool>(AF_INET, false),
40 std::make_pair<int, bool>(AF_INET, true),
41 std::make_pair<int, bool>(AF_INET6, false),
42 std::make_pair<int, bool>(AF_INET6, true)
43 };
44 const std::vector<std::pair<int, bool>> ipv4_family_both_modes = {
45 std::make_pair<int, bool>(AF_INET, false),
46 std::make_pair<int, bool>(AF_INET, true)
47 };
48 const std::vector<std::pair<int, bool>> ipv6_family_both_modes = {
49 std::make_pair<int, bool>(AF_INET6, false),
50 std::make_pair<int, bool>(AF_INET6, true)
51 };
52
53 // Which parameters to use in tests
54 std::vector<int> families = both_families;
55 std::vector<std::pair<int, bool>> families_modes = both_families_both_modes;
56
57 unsigned long long LibraryTest::fails_ = 0;
58 std::map<size_t, int> LibraryTest::size_fails_;
59
ProcessWork(ares_channel channel,std::function<std::set<int> ()> get_extrafds,std::function<void (int)> process_extra)60 void ProcessWork(ares_channel channel,
61 std::function<std::set<int>()> get_extrafds,
62 std::function<void(int)> process_extra) {
63 int nfds, count;
64 fd_set readers, writers;
65 struct timeval tv;
66 while (true) {
67 // Retrieve the set of file descriptors that the library wants us to monitor.
68 FD_ZERO(&readers);
69 FD_ZERO(&writers);
70 nfds = ares_fds(channel, &readers, &writers);
71 if (nfds == 0) // no work left to do in the library
72 return;
73
74 // Add in the extra FDs if present.
75 std::set<int> extrafds = get_extrafds();
76 for (int extrafd : extrafds) {
77 FD_SET(extrafd, &readers);
78 if (extrafd >= nfds) {
79 nfds = extrafd + 1;
80 }
81 }
82
83 // Wait for activity or timeout.
84 tv.tv_sec = 0;
85 tv.tv_usec = 100000; // 100ms
86 count = select(nfds, &readers, &writers, nullptr, &tv);
87 if (count < 0) {
88 fprintf(stderr, "select() failed, errno %d\n", errno);
89 return;
90 }
91
92 // Let the library process any activity.
93 ares_process(channel, &readers, &writers);
94
95 // Let the provided callback process any activity on the extra FD.
96 for (int extrafd : extrafds) {
97 if (FD_ISSET(extrafd, &readers)) {
98 process_extra(extrafd);
99 }
100 }
101 }
102 }
103
104 // static
SetAllocFail(int nth)105 void LibraryTest::SetAllocFail(int nth) {
106 assert(nth > 0);
107 assert(nth <= (int)(8 * sizeof(fails_)));
108 fails_ |= (1LL << (nth - 1));
109 }
110
111 // static
SetAllocSizeFail(size_t size)112 void LibraryTest::SetAllocSizeFail(size_t size) {
113 size_fails_[size]++;
114 }
115
116 // static
ClearFails()117 void LibraryTest::ClearFails() {
118 fails_ = 0;
119 size_fails_.clear();
120 }
121
122
123 // static
ShouldAllocFail(size_t size)124 bool LibraryTest::ShouldAllocFail(size_t size) {
125 bool fail = (fails_ & 0x01);
126 fails_ >>= 1;
127 if (size_fails_[size] > 0) {
128 size_fails_[size]--;
129 fail = true;
130 }
131 return fail;
132 }
133
134 // static
amalloc(size_t size)135 void* LibraryTest::amalloc(size_t size) {
136 if (ShouldAllocFail(size)) {
137 if (verbose) std::cerr << "Failing malloc(" << size << ") request" << std::endl;
138 return nullptr;
139 } else {
140 return malloc(size);
141 }
142 }
143
144 // static
arealloc(void * ptr,size_t size)145 void* LibraryTest::arealloc(void *ptr, size_t size) {
146 if (ShouldAllocFail(size)) {
147 if (verbose) std::cerr << "Failing realloc(" << ptr << ", " << size << ") request" << std::endl;
148 return nullptr;
149 } else {
150 return realloc(ptr, size);
151 }
152 }
153
154 // static
afree(void * ptr)155 void LibraryTest::afree(void *ptr) {
156 free(ptr);
157 }
158
NoExtraFDs()159 std::set<int> NoExtraFDs() {
160 return std::set<int>();
161 }
162
Process()163 void DefaultChannelTest::Process() {
164 ProcessWork(channel_, NoExtraFDs, nullptr);
165 }
166
Process()167 void DefaultChannelModeTest::Process() {
168 ProcessWork(channel_, NoExtraFDs, nullptr);
169 }
170
MockServer(int family,int port,int tcpport)171 MockServer::MockServer(int family, int port, int tcpport)
172 : udpport_(port), tcpport_(tcpport ? tcpport : udpport_), qid_(-1) {
173 // Create a TCP socket to receive data on.
174 tcpfd_ = socket(family, SOCK_STREAM, 0);
175 EXPECT_NE(-1, tcpfd_);
176 int optval = 1;
177 setsockopt(tcpfd_, SOL_SOCKET, SO_REUSEADDR,
178 BYTE_CAST &optval , sizeof(int));
179 // Send TCP data right away.
180 setsockopt(tcpfd_, IPPROTO_TCP, TCP_NODELAY,
181 BYTE_CAST &optval , sizeof(int));
182
183 // Create a UDP socket to receive data on.
184 udpfd_ = socket(family, SOCK_DGRAM, 0);
185 EXPECT_NE(-1, udpfd_);
186
187 // Bind the sockets to the given port.
188 if (family == AF_INET) {
189 struct sockaddr_in addr;
190 memset(&addr, 0, sizeof(addr));
191 addr.sin_family = AF_INET;
192 addr.sin_addr.s_addr = htonl(INADDR_ANY);
193 addr.sin_port = htons(tcpport_);
194 int tcprc = bind(tcpfd_, (struct sockaddr*)&addr, sizeof(addr));
195 EXPECT_EQ(0, tcprc) << "Failed to bind AF_INET to TCP port " << tcpport_;
196 addr.sin_port = htons(udpport_);
197 int udprc = bind(udpfd_, (struct sockaddr*)&addr, sizeof(addr));
198 EXPECT_EQ(0, udprc) << "Failed to bind AF_INET to UDP port " << udpport_;
199 } else {
200 EXPECT_EQ(AF_INET6, family);
201 struct sockaddr_in6 addr;
202 memset(&addr, 0, sizeof(addr));
203 addr.sin6_family = AF_INET6;
204 memset(&addr.sin6_addr, 0, sizeof(addr.sin6_addr)); // in6addr_any
205 addr.sin6_port = htons(tcpport_);
206 int tcprc = bind(tcpfd_, (struct sockaddr*)&addr, sizeof(addr));
207 EXPECT_EQ(0, tcprc) << "Failed to bind AF_INET6 to TCP port " << tcpport_;
208 addr.sin6_port = htons(udpport_);
209 int udprc = bind(udpfd_, (struct sockaddr*)&addr, sizeof(addr));
210 EXPECT_EQ(0, udprc) << "Failed to bind AF_INET6 to UDP port " << udpport_;
211 }
212 if (verbose) std::cerr << "Configured "
213 << (family == AF_INET ? "IPv4" : "IPv6")
214 << " mock server with TCP socket " << tcpfd_
215 << " on port " << tcpport_
216 << " and UDP socket " << udpfd_
217 << " on port " << udpport_ << std::endl;
218
219 // For TCP, also need to listen for connections.
220 EXPECT_EQ(0, listen(tcpfd_, 5)) << "Failed to listen for TCP connections";
221 }
222
~MockServer()223 MockServer::~MockServer() {
224 for (int fd : connfds_) {
225 sclose(fd);
226 }
227 sclose(tcpfd_);
228 sclose(udpfd_);
229 }
230
ProcessFD(int fd)231 void MockServer::ProcessFD(int fd) {
232 if (fd != tcpfd_ && fd != udpfd_ && connfds_.find(fd) == connfds_.end()) {
233 // Not one of our FDs.
234 return;
235 }
236 if (fd == tcpfd_) {
237 int connfd = accept(tcpfd_, NULL, NULL);
238 if (connfd < 0) {
239 std::cerr << "Error accepting connection on fd " << fd << std::endl;
240 } else {
241 connfds_.insert(connfd);
242 }
243 return;
244 }
245
246 // Activity on a data-bearing file descriptor.
247 struct sockaddr_storage addr;
248 socklen_t addrlen = sizeof(addr);
249 byte buffer[2048];
250 int len = recvfrom(fd, BYTE_CAST buffer, sizeof(buffer), 0,
251 (struct sockaddr *)&addr, &addrlen);
252 byte* data = buffer;
253 if (fd != udpfd_) {
254 if (len == 0) {
255 connfds_.erase(std::find(connfds_.begin(), connfds_.end(), fd));
256 sclose(fd);
257 return;
258 }
259 if (len < 2) {
260 std::cerr << "Packet too short (" << len << ")" << std::endl;
261 return;
262 }
263 int tcplen = (data[0] << 8) + data[1];
264 data += 2;
265 len -= 2;
266 if (tcplen != len) {
267 std::cerr << "Warning: TCP length " << tcplen
268 << " doesn't match remaining data length " << len << std::endl;
269 }
270 }
271
272 // Assume the packet is a well-formed DNS request and extract the request
273 // details.
274 if (len < NS_HFIXEDSZ) {
275 std::cerr << "Packet too short (" << len << ")" << std::endl;
276 return;
277 }
278 int qid = DNS_HEADER_QID(data);
279 if (DNS_HEADER_QR(data) != 0) {
280 std::cerr << "Not a request" << std::endl;
281 return;
282 }
283 if (DNS_HEADER_OPCODE(data) != ns_o_query) {
284 std::cerr << "Not a query (opcode " << DNS_HEADER_OPCODE(data)
285 << ")" << std::endl;
286 return;
287 }
288 if (DNS_HEADER_QDCOUNT(data) != 1) {
289 std::cerr << "Unexpected question count (" << DNS_HEADER_QDCOUNT(data)
290 << ")" << std::endl;
291 return;
292 }
293 byte* question = data + 12;
294 int qlen = len - 12;
295
296 char *name = nullptr;
297 long enclen;
298 ares_expand_name(question, data, len, &name, &enclen);
299 if (!name) {
300 std::cerr << "Failed to retrieve name" << std::endl;
301 return;
302 }
303 qlen -= enclen;
304 question += enclen;
305 std::string namestr(name);
306 ares_free_string(name);
307
308 if (qlen < 4) {
309 std::cerr << "Unexpected question size (" << qlen
310 << " bytes after name)" << std::endl;
311 return;
312 }
313 if (DNS_QUESTION_CLASS(question) != ns_c_in) {
314 std::cerr << "Unexpected question class (" << DNS_QUESTION_CLASS(question)
315 << ")" << std::endl;
316 return;
317 }
318 int rrtype = DNS_QUESTION_TYPE(question);
319
320 if (verbose) {
321 std::vector<byte> req(data, data + len);
322 std::cerr << "received " << (fd == udpfd_ ? "UDP" : "TCP") << " request " << PacketToString(req)
323 << " on port " << (fd == udpfd_ ? udpport_ : tcpport_) << std::endl;
324 std::cerr << "ProcessRequest(" << qid << ", '" << namestr
325 << "', " << RRTypeToString(rrtype) << ")" << std::endl;
326 }
327 ProcessRequest(fd, &addr, addrlen, qid, namestr, rrtype);
328 }
329
fds() const330 std::set<int> MockServer::fds() const {
331 std::set<int> result = connfds_;
332 result.insert(tcpfd_);
333 result.insert(udpfd_);
334 return result;
335 }
336
ProcessRequest(int fd,struct sockaddr_storage * addr,int addrlen,int qid,const std::string & name,int rrtype)337 void MockServer::ProcessRequest(int fd, struct sockaddr_storage* addr, int addrlen,
338 int qid, const std::string& name, int rrtype) {
339 // Before processing, let gMock know the request is happening.
340 OnRequest(name, rrtype);
341
342 if (reply_.size() == 0) {
343 return;
344 }
345
346 // Make a local copy of the current pending reply.
347 std::vector<byte> reply = reply_;
348
349 if (qid_ >= 0) {
350 // Use the explicitly specified query ID.
351 qid = qid_;
352 }
353 if (reply.size() >= 2) {
354 // Overwrite the query ID if space to do so.
355 reply[0] = (byte)((qid >> 8) & 0xff);
356 reply[1] = (byte)(qid & 0xff);
357 }
358 if (verbose) std::cerr << "sending reply " << PacketToString(reply)
359 << " on port " << ((fd == udpfd_) ? udpport_ : tcpport_) << std::endl;
360
361 // Prefix with 2-byte length if TCP.
362 if (fd != udpfd_) {
363 int len = reply.size();
364 std::vector<byte> vlen = {(byte)((len & 0xFF00) >> 8), (byte)(len & 0xFF)};
365 reply.insert(reply.begin(), vlen.begin(), vlen.end());
366 // Also, don't bother with the destination address.
367 addr = nullptr;
368 addrlen = 0;
369 }
370
371 int rc = sendto(fd, BYTE_CAST reply.data(), reply.size(), 0,
372 (struct sockaddr *)addr, addrlen);
373 if (rc < static_cast<int>(reply.size())) {
374 std::cerr << "Failed to send full reply, rc=" << rc << std::endl;
375 }
376 }
377
378 // static
BuildServers(int count,int family,int base_port)379 MockChannelOptsTest::NiceMockServers MockChannelOptsTest::BuildServers(int count, int family, int base_port) {
380 NiceMockServers servers;
381 assert(count > 0);
382 for (int ii = 0; ii < count; ii++) {
383 std::unique_ptr<NiceMockServer> server(new NiceMockServer(family, base_port + ii));
384 servers.push_back(std::move(server));
385 }
386 return servers;
387 }
388
MockChannelOptsTest(int count,int family,bool force_tcp,struct ares_options * givenopts,int optmask)389 MockChannelOptsTest::MockChannelOptsTest(int count,
390 int family,
391 bool force_tcp,
392 struct ares_options* givenopts,
393 int optmask)
394 : servers_(BuildServers(count, family, mock_port)),
395 server_(*servers_[0].get()), channel_(nullptr) {
396 // Set up channel options.
397 struct ares_options opts;
398 if (givenopts) {
399 memcpy(&opts, givenopts, sizeof(opts));
400 } else {
401 memset(&opts, 0, sizeof(opts));
402 }
403
404 // Point the library at the first mock server by default (overridden below).
405 opts.udp_port = mock_port;
406 optmask |= ARES_OPT_UDP_PORT;
407 opts.tcp_port = mock_port;
408 optmask |= ARES_OPT_TCP_PORT;
409
410 // If not already overridden, set short-ish timeouts.
411 if (!(optmask & (ARES_OPT_TIMEOUTMS|ARES_OPT_TIMEOUT))) {
412 opts.timeout = 1500;
413 optmask |= ARES_OPT_TIMEOUTMS;
414 }
415 // If not already overridden, set 3 retries.
416 if (!(optmask & ARES_OPT_TRIES)) {
417 opts.tries = 3;
418 optmask |= ARES_OPT_TRIES;
419 }
420 // If not already overridden, set search domains.
421 const char *domains[3] = {"first.com", "second.org", "third.gov"};
422 if (!(optmask & ARES_OPT_DOMAINS)) {
423 opts.ndomains = 3;
424 opts.domains = (char**)domains;
425 optmask |= ARES_OPT_DOMAINS;
426 }
427 if (force_tcp) {
428 opts.flags |= ARES_FLAG_USEVC;
429 optmask |= ARES_OPT_FLAGS;
430 }
431
432 EXPECT_EQ(ARES_SUCCESS, ares_init_options(&channel_, &opts, optmask));
433 EXPECT_NE(nullptr, channel_);
434
435 // Set up servers after construction so we can set individual ports
436 struct ares_addr_port_node* prev = nullptr;
437 struct ares_addr_port_node* first = nullptr;
438 for (const auto& server : servers_) {
439 struct ares_addr_port_node* node = (struct ares_addr_port_node*)malloc(sizeof(*node));
440 if (prev) {
441 prev->next = node;
442 } else {
443 first = node;
444 }
445 node->next = nullptr;
446 node->family = family;
447 node->udp_port = server->udpport();
448 node->tcp_port = server->tcpport();
449 if (family == AF_INET) {
450 node->addr.addr4.s_addr = htonl(0x7F000001);
451 } else {
452 memset(&node->addr.addr6, 0, sizeof(node->addr.addr6));
453 node->addr.addr6._S6_un._S6_u8[15] = 1;
454 }
455 prev = node;
456 }
457 EXPECT_EQ(ARES_SUCCESS, ares_set_servers_ports(channel_, first));
458
459 while (first) {
460 prev = first;
461 first = first->next;
462 free(prev);
463 }
464 if (verbose) {
465 std::cerr << "Configured library with servers:";
466 std::vector<std::string> servers = GetNameServers(channel_);
467 for (const auto& server : servers) {
468 std::cerr << " " << server;
469 }
470 std::cerr << std::endl;
471 }
472 }
473
~MockChannelOptsTest()474 MockChannelOptsTest::~MockChannelOptsTest() {
475 if (channel_) {
476 ares_destroy(channel_);
477 }
478 channel_ = nullptr;
479 }
480
fds() const481 std::set<int> MockChannelOptsTest::fds() const {
482 std::set<int> fds;
483 for (const auto& server : servers_) {
484 std::set<int> serverfds = server->fds();
485 fds.insert(serverfds.begin(), serverfds.end());
486 }
487 return fds;
488 }
489
ProcessFD(int fd)490 void MockChannelOptsTest::ProcessFD(int fd) {
491 for (auto& server : servers_) {
492 server->ProcessFD(fd);
493 }
494 }
495
Process()496 void MockChannelOptsTest::Process() {
497 using namespace std::placeholders;
498 ProcessWork(channel_,
499 std::bind(&MockChannelOptsTest::fds, this),
500 std::bind(&MockChannelOptsTest::ProcessFD, this, _1));
501 }
502
operator <<(std::ostream & os,const HostResult & result)503 std::ostream& operator<<(std::ostream& os, const HostResult& result) {
504 os << '{';
505 if (result.done_) {
506 os << StatusToString(result.status_) << " " << result.host_;
507 } else {
508 os << "(incomplete)";
509 }
510 os << '}';
511 return os;
512 }
513
HostEnt(const struct hostent * hostent)514 HostEnt::HostEnt(const struct hostent *hostent) : addrtype_(-1) {
515 if (!hostent)
516 return;
517 if (hostent->h_name)
518 name_ = hostent->h_name;
519 if (hostent->h_aliases) {
520 char** palias = hostent->h_aliases;
521 while (*palias != nullptr) {
522 aliases_.push_back(*palias);
523 palias++;
524 }
525 }
526 addrtype_ = hostent->h_addrtype;
527 if (hostent->h_addr_list) {
528 char** paddr = hostent->h_addr_list;
529 while (*paddr != nullptr) {
530 std::string addr = AddressToString(*paddr, hostent->h_length);
531 addrs_.push_back(addr);
532 paddr++;
533 }
534 }
535 }
536
operator <<(std::ostream & os,const HostEnt & host)537 std::ostream& operator<<(std::ostream& os, const HostEnt& host) {
538 os << '{';
539 os << "'" << host.name_ << "' "
540 << "aliases=[";
541 for (size_t ii = 0; ii < host.aliases_.size(); ii++) {
542 if (ii > 0) os << ", ";
543 os << host.aliases_[ii];
544 }
545 os << "] ";
546 os << "addrs=[";
547 for (size_t ii = 0; ii < host.addrs_.size(); ii++) {
548 if (ii > 0) os << ", ";
549 os << host.addrs_[ii];
550 }
551 os << "]";
552 os << '}';
553 return os;
554 }
555
HostCallback(void * data,int status,int timeouts,struct hostent * hostent)556 void HostCallback(void *data, int status, int timeouts,
557 struct hostent *hostent) {
558 EXPECT_NE(nullptr, data);
559 HostResult* result = reinterpret_cast<HostResult*>(data);
560 result->done_ = true;
561 result->status_ = status;
562 result->timeouts_ = timeouts;
563 result->host_ = HostEnt(hostent);
564 if (verbose) std::cerr << "HostCallback(" << *result << ")" << std::endl;
565 }
566
operator <<(std::ostream & os,const SearchResult & result)567 std::ostream& operator<<(std::ostream& os, const SearchResult& result) {
568 os << '{';
569 if (result.done_) {
570 os << StatusToString(result.status_) << " " << PacketToString(result.data_);
571 } else {
572 os << "(incomplete)";
573 }
574 os << '}';
575 return os;
576 }
577
SearchCallback(void * data,int status,int timeouts,unsigned char * abuf,int alen)578 void SearchCallback(void *data, int status, int timeouts,
579 unsigned char *abuf, int alen) {
580 EXPECT_NE(nullptr, data);
581 SearchResult* result = reinterpret_cast<SearchResult*>(data);
582 result->done_ = true;
583 result->status_ = status;
584 result->timeouts_ = timeouts;
585 result->data_.assign(abuf, abuf + alen);
586 if (verbose) std::cerr << "SearchCallback(" << *result << ")" << std::endl;
587 }
588
operator <<(std::ostream & os,const NameInfoResult & result)589 std::ostream& operator<<(std::ostream& os, const NameInfoResult& result) {
590 os << '{';
591 if (result.done_) {
592 os << StatusToString(result.status_) << " " << result.node_ << " " << result.service_;
593 } else {
594 os << "(incomplete)";
595 }
596 os << '}';
597 return os;
598 }
599
NameInfoCallback(void * data,int status,int timeouts,char * node,char * service)600 void NameInfoCallback(void *data, int status, int timeouts,
601 char *node, char *service) {
602 EXPECT_NE(nullptr, data);
603 NameInfoResult* result = reinterpret_cast<NameInfoResult*>(data);
604 result->done_ = true;
605 result->status_ = status;
606 result->timeouts_ = timeouts;
607 result->node_ = std::string(node ? node : "");
608 result->service_ = std::string(service ? service : "");
609 if (verbose) std::cerr << "NameInfoCallback(" << *result << ")" << std::endl;
610 }
611
GetNameServers(ares_channel channel)612 std::vector<std::string> GetNameServers(ares_channel channel) {
613 struct ares_addr_port_node* servers = nullptr;
614 EXPECT_EQ(ARES_SUCCESS, ares_get_servers_ports(channel, &servers));
615 struct ares_addr_port_node* server = servers;
616 std::vector<std::string> results;
617 while (server) {
618 std::stringstream ss;
619 switch (server->family) {
620 case AF_INET:
621 ss << AddressToString((char*)&server->addr.addr4, 4);
622 break;
623 case AF_INET6:
624 if (server->udp_port != 0) {
625 ss << '[';
626 }
627 ss << AddressToString((char*)&server->addr.addr6, 16);
628 if (server->udp_port != 0) {
629 ss << ']';
630 }
631 break;
632 default:
633 results.push_back("<unknown family>");
634 break;
635 }
636 if (server->udp_port != 0) {
637 ss << ":" << server->udp_port;
638 }
639 results.push_back(ss.str());
640 server = server->next;
641 }
642 if (servers) ares_free_data(servers);
643 return results;
644 }
645
TransientDir(const std::string & dirname)646 TransientDir::TransientDir(const std::string& dirname) : dirname_(dirname) {
647 if (mkdir_(dirname_.c_str(), 0755) != 0) {
648 std::cerr << "Failed to create subdirectory '" << dirname_ << "'" << std::endl;
649 }
650 }
651
~TransientDir()652 TransientDir::~TransientDir() {
653 rmdir(dirname_.c_str());
654 }
655
TransientFile(const std::string & filename,const std::string & contents)656 TransientFile::TransientFile(const std::string& filename,
657 const std::string& contents)
658 : filename_(filename) {
659 FILE *f = fopen(filename.c_str(), "w");
660 if (f == nullptr) {
661 std::cerr << "Error: failed to create '" << filename << "'" << std::endl;
662 return;
663 }
664 int rc = fwrite(contents.data(), 1, contents.size(), f);
665 if (rc != (int)contents.size()) {
666 std::cerr << "Error: failed to write contents of '" << filename << "'" << std::endl;
667 }
668 fclose(f);
669 }
670
~TransientFile()671 TransientFile::~TransientFile() {
672 unlink(filename_.c_str());
673 }
674
TempNam(const char * dir,const char * prefix)675 std::string TempNam(const char *dir, const char *prefix) {
676 char *p = tempnam(dir, prefix);
677 std::string result(p);
678 free(p);
679 return result;
680 }
681
TempFile(const std::string & contents)682 TempFile::TempFile(const std::string& contents)
683 : TransientFile(TempNam(nullptr, "ares"), contents) {
684
685 }
686
VirtualizeIO(ares_channel c)687 VirtualizeIO::VirtualizeIO(ares_channel c)
688 : channel_(c)
689 {
690 ares_set_socket_functions(channel_, &default_functions, 0);
691 }
692
~VirtualizeIO()693 VirtualizeIO::~VirtualizeIO() {
694 ares_set_socket_functions(channel_, 0, 0);
695 }
696
697 } // namespace test
698 } // namespace ares
699