1 //
2 // Automated Testing Framework (atf)
3 //
4 // Copyright (c) 2007 The NetBSD Foundation, Inc.
5 // All rights reserved.
6 //
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8 // modification, are permitted provided that the following conditions
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11 //    notice, this list of conditions and the following disclaimer.
12 // 2. Redistributions in binary form must reproduce the above copyright
13 //    notice, this list of conditions and the following disclaimer in the
14 //    documentation and/or other materials provided with the distribution.
15 //
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17 // CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
18 // INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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28 //
29 
30 extern "C" {
31 #include <sys/types.h>
32 #include <sys/stat.h>
33 #include <sys/time.h>
34 
35 #include <fcntl.h>
36 #include <signal.h>
37 #include <unistd.h>
38 }
39 
40 #include <cassert>
41 #include <cerrno>
42 #include <cstdlib>
43 #include <cstring>
44 #include <fstream>
45 #include <iostream>
46 
47 #include "config_file.hpp"
48 #include "env.hpp"
49 #include "fs.hpp"
50 #include "io.hpp"
51 #include "parser.hpp"
52 #include "process.hpp"
53 #include "requirements.hpp"
54 #include "signals.hpp"
55 #include "test-program.hpp"
56 #include "text.hpp"
57 #include "timers.hpp"
58 #include "user.hpp"
59 
60 namespace impl = tools::test_program;
61 namespace detail = tools::test_program::detail;
62 
63 namespace {
64 
65 typedef std::map< std::string, std::string > vars_map;
66 
67 static void
68 check_stream(std::ostream& os)
69 {
70     // If we receive a signal while writing to the stream, the bad bit gets set.
71     // Things seem to behave fine afterwards if we clear such error condition.
72     // However, I'm not sure if it's safe to query errno at this point.
73     if (os.bad()) {
74         if (errno == EINTR)
75             os.clear();
76         else
77             throw std::runtime_error("Failed");
78     }
79 }
80 
81 namespace atf_tp {
82 
83 static const tools::parser::token_type eof_type = 0;
84 static const tools::parser::token_type nl_type = 1;
85 static const tools::parser::token_type text_type = 2;
86 static const tools::parser::token_type colon_type = 3;
87 static const tools::parser::token_type dblquote_type = 4;
88 
89 class tokenizer : public tools::parser::tokenizer< std::istream > {
90 public:
91     tokenizer(std::istream& is, size_t curline) :
92         tools::parser::tokenizer< std::istream >
93             (is, true, eof_type, nl_type, text_type, curline)
94     {
95         add_delim(':', colon_type);
96         add_quote('"', dblquote_type);
97     }
98 };
99 
100 } // namespace atf_tp
101 
102 class metadata_reader : public detail::atf_tp_reader {
103     impl::test_cases_map m_tcs;
104 
105     void got_tc(const std::string& ident, const vars_map& props)
106     {
107         if (m_tcs.find(ident) != m_tcs.end())
108             throw(std::runtime_error("Duplicate test case " + ident +
109                                      " in test program"));
110         m_tcs[ident] = props;
111 
112         if (m_tcs[ident].find("has.cleanup") == m_tcs[ident].end())
113             m_tcs[ident].insert(std::make_pair("has.cleanup", "false"));
114 
115         if (m_tcs[ident].find("timeout") == m_tcs[ident].end())
116             m_tcs[ident].insert(std::make_pair("timeout", "300"));
117     }
118 
119 public:
120     metadata_reader(std::istream& is) :
121         detail::atf_tp_reader(is)
122     {
123     }
124 
125     const impl::test_cases_map&
126     get_tcs(void)
127         const
128     {
129         return m_tcs;
130     }
131 };
132 
133 struct get_metadata_params {
134     const tools::fs::path& executable;
135     const vars_map& config;
136 
137     get_metadata_params(const tools::fs::path& p_executable,
138                         const vars_map& p_config) :
139         executable(p_executable),
140         config(p_config)
141     {
142     }
143 };
144 
145 struct test_case_params {
146     const tools::fs::path& executable;
147     const std::string& test_case_name;
148     const std::string& test_case_part;
149     const vars_map& metadata;
150     const vars_map& config;
151     const tools::fs::path& resfile;
152     const tools::fs::path& workdir;
153 
154     test_case_params(const tools::fs::path& p_executable,
155                      const std::string& p_test_case_name,
156                      const std::string& p_test_case_part,
157                      const vars_map& p_metadata,
158                      const vars_map& p_config,
159                      const tools::fs::path& p_resfile,
160                      const tools::fs::path& p_workdir) :
161         executable(p_executable),
162         test_case_name(p_test_case_name),
163         test_case_part(p_test_case_part),
164         metadata(p_metadata),
165         config(p_config),
166         resfile(p_resfile),
167         workdir(p_workdir)
168     {
169     }
170 };
171 
172 static
173 std::string
174 generate_timestamp(void)
175 {
176     struct timeval tv;
177     if (gettimeofday(&tv, NULL) == -1)
178         return "0.0";
179 
180     char buf[32];
181     const int len = snprintf(buf, sizeof(buf), "%ld.%ld",
182                              static_cast< long >(tv.tv_sec),
183                              static_cast< long >(tv.tv_usec));
184     if (len >= static_cast< int >(sizeof(buf)) || len < 0)
185         return "0.0";
186     else
187         return buf;
188 }
189 
190 static
191 void
192 append_to_vector(std::vector< std::string >& v1,
193                  const std::vector< std::string >& v2)
194 {
195     std::copy(v2.begin(), v2.end(),
196               std::back_insert_iterator< std::vector< std::string > >(v1));
197 }
198 
199 static
200 char**
201 vector_to_argv(const std::vector< std::string >& v)
202 {
203     char** argv = new char*[v.size() + 1];
204     for (std::vector< std::string >::size_type i = 0; i < v.size(); i++) {
205         argv[i] = strdup(v[i].c_str());
206     }
207     argv[v.size()] = NULL;
208     return argv;
209 }
210 
211 static
212 void
213 exec_or_exit(const tools::fs::path& executable,
214              const std::vector< std::string >& argv)
215 {
216     // This leaks memory in case of a failure, but it is OK.  Exiting will
217     // do the necessary cleanup.
218     char* const* native_argv = vector_to_argv(argv);
219 
220     ::execv(executable.c_str(), native_argv);
221 
222     const std::string message = "Failed to execute '" + executable.str() +
223         "': " + std::strerror(errno) + "\n";
224     if (::write(STDERR_FILENO, message.c_str(), message.length()) == -1)
225         std::abort();
226     std::exit(EXIT_FAILURE);
227 }
228 
229 static
230 std::vector< std::string >
231 config_to_args(const vars_map& config)
232 {
233     std::vector< std::string > args;
234 
235     for (vars_map::const_iterator iter = config.begin();
236          iter != config.end(); iter++)
237         args.push_back("-v" + (*iter).first + "=" + (*iter).second);
238 
239     return args;
240 }
241 
242 static
243 void
244 silence_stdin(void)
245 {
246     ::close(STDIN_FILENO);
247     int fd = ::open("/dev/null", O_RDONLY);
248     if (fd == -1)
249         throw std::runtime_error("Could not open /dev/null");
250     assert(fd == STDIN_FILENO);
251 }
252 
253 static
254 void
255 prepare_child(const tools::fs::path& workdir)
256 {
257 #if !defined(NDEBUG) && defined(__minix)
258     const int ret =
259 #endif /* !defined(NDEBUG) && defined(__minix) */
260     	::setpgid(::getpid(), 0);
261     assert(ret != -1);
262 
263     ::umask(S_IWGRP | S_IWOTH);
264 
265     for (int i = 1; i <= tools::signals::last_signo; i++)
266         tools::signals::reset(i);
267 
268     tools::env::set("HOME", workdir.str());
269     tools::env::unset("LANG");
270     tools::env::unset("LC_ALL");
271     tools::env::unset("LC_COLLATE");
272     tools::env::unset("LC_CTYPE");
273     tools::env::unset("LC_MESSAGES");
274     tools::env::unset("LC_MONETARY");
275     tools::env::unset("LC_NUMERIC");
276     tools::env::unset("LC_TIME");
277     tools::env::set("TZ", "UTC");
278 
279     tools::env::set("__RUNNING_INSIDE_ATF_RUN", "internal-yes-value");
280 
281     tools::fs::change_directory(workdir);
282 
283     silence_stdin();
284 }
285 
286 static
287 void
288 get_metadata_child(void* raw_params)
289 {
290     const get_metadata_params* params =
291         static_cast< const get_metadata_params* >(raw_params);
292 
293     std::vector< std::string > argv;
294     argv.push_back(params->executable.leaf_name());
295     argv.push_back("-l");
296     argv.push_back("-s" + params->executable.branch_path().str());
297     append_to_vector(argv, config_to_args(params->config));
298 
299     exec_or_exit(params->executable, argv);
300 }
301 
302 void
303 run_test_case_child(void* raw_params)
304 {
305     const test_case_params* params =
306         static_cast< const test_case_params* >(raw_params);
307 
308     const std::pair< int, int > user = tools::get_required_user(
309         params->metadata, params->config);
310     if (user.first != -1 && user.second != -1)
311         tools::user::drop_privileges(user);
312 
313     // The input 'tp' parameter may be relative and become invalid once
314     // we change the current working directory.
315     const tools::fs::path absolute_executable = params->executable.to_absolute();
316 
317     // Prepare the test program's arguments.  We use dynamic memory and
318     // do not care to release it.  We are going to die anyway very soon,
319     // either due to exec(2) or to exit(3).
320     std::vector< std::string > argv;
321     argv.push_back(absolute_executable.leaf_name());
322     argv.push_back("-r" + params->resfile.str());
323     argv.push_back("-s" + absolute_executable.branch_path().str());
324     append_to_vector(argv, config_to_args(params->config));
325     argv.push_back(params->test_case_name + ":" + params->test_case_part);
326 
327     prepare_child(params->workdir);
328     exec_or_exit(absolute_executable, argv);
329 }
330 
331 static void
332 tokenize_result(const std::string& line, std::string& out_state,
333                 std::string& out_arg, std::string& out_reason)
334 {
335     const std::string::size_type pos = line.find_first_of(":(");
336     if (pos == std::string::npos) {
337         out_state = line;
338         out_arg = "";
339         out_reason = "";
340     } else if (line[pos] == ':') {
341         out_state = line.substr(0, pos);
342         out_arg = "";
343         out_reason = tools::text::trim(line.substr(pos + 1));
344     } else if (line[pos] == '(') {
345         const std::string::size_type pos2 = line.find("):", pos);
346         if (pos2 == std::string::npos)
347             throw std::runtime_error("Invalid test case result '" + line +
348                 "': unclosed optional argument");
349         out_state = line.substr(0, pos);
350         out_arg = line.substr(pos + 1, pos2 - pos - 1);
351         out_reason = tools::text::trim(line.substr(pos2 + 2));
352     } else
353         std::abort();
354 }
355 
356 static impl::test_case_result
357 handle_result(const std::string& state, const std::string& arg,
358               const std::string& reason)
359 {
360     assert(state == "passed");
361 
362     if (!arg.empty() || !reason.empty())
363         throw std::runtime_error("The test case result '" + state + "' cannot "
364             "be accompanied by a reason nor an expected value");
365 
366     return impl::test_case_result(state, -1, reason);
367 }
368 
369 static impl::test_case_result
370 handle_result_with_reason(const std::string& state, const std::string& arg,
371                           const std::string& reason)
372 {
373     assert(state == "expected_death" || state == "expected_failure" ||
374         state == "expected_timeout" || state == "failed" || state == "skipped");
375 
376     if (!arg.empty() || reason.empty())
377         throw std::runtime_error("The test case result '" + state + "' must "
378             "be accompanied by a reason but not by an expected value");
379 
380     return impl::test_case_result(state, -1, reason);
381 }
382 
383 static impl::test_case_result
384 handle_result_with_reason_and_arg(const std::string& state,
385                                   const std::string& arg,
386                                   const std::string& reason)
387 {
388     assert(state == "expected_exit" || state == "expected_signal");
389 
390     if (reason.empty())
391         throw std::runtime_error("The test case result '" + state + "' must "
392             "be accompanied by a reason");
393 
394     int value;
395     if (arg.empty()) {
396         value = -1;
397     } else {
398         try {
399             value = tools::text::to_type< int >(arg);
400         } catch (const std::runtime_error&) {
401             throw std::runtime_error("The value '" + arg + "' passed to the '" +
402                 state + "' state must be an integer");
403         }
404     }
405 
406     return impl::test_case_result(state, value, reason);
407 }
408 
409 } // anonymous namespace
410 
411 detail::atf_tp_reader::atf_tp_reader(std::istream& is) :
412     m_is(is)
413 {
414 }
415 
416 detail::atf_tp_reader::~atf_tp_reader(void)
417 {
418 }
419 
420 void
421 detail::atf_tp_reader::got_tc(
422     const std::string& ident __attribute__((__unused__)),
423     const std::map< std::string, std::string >& md __attribute__((__unused__)))
424 {
425 }
426 
427 void
428 detail::atf_tp_reader::got_eof(void)
429 {
430 }
431 
432 void
433 detail::atf_tp_reader::validate_and_insert(const std::string& name,
434     const std::string& value, const size_t lineno,
435     std::map< std::string, std::string >& md)
436 {
437     using tools::parser::parse_error;
438 
439     if (value.empty())
440         throw parse_error(lineno, "The value for '" + name +"' cannot be "
441                           "empty");
442 
443     const std::string ident_regex = "^[_A-Za-z0-9]+$";
444     const std::string integer_regex = "^[0-9]+$";
445 
446     if (name == "descr") {
447         // Any non-empty value is valid.
448     } else if (name == "has.cleanup") {
449         try {
450             (void)tools::text::to_bool(value);
451         } catch (const std::runtime_error&) {
452             throw parse_error(lineno, "The has.cleanup property requires a"
453                               " boolean value");
454         }
455     } else if (name == "ident") {
456         if (!tools::text::match(value, ident_regex))
457             throw parse_error(lineno, "The identifier must match " +
458                               ident_regex + "; was '" + value + "'");
459     } else if (name == "require.arch") {
460     } else if (name == "require.config") {
461     } else if (name == "require.files") {
462     } else if (name == "require.machine") {
463     } else if (name == "require.memory") {
464         try {
465             (void)tools::text::to_bytes(value);
466         } catch (const std::runtime_error&) {
467             throw parse_error(lineno, "The require.memory property requires an "
468                               "integer value representing an amount of bytes");
469         }
470     } else if (name == "require.progs") {
471     } else if (name == "require.user") {
472     } else if (name == "timeout") {
473         if (!tools::text::match(value, integer_regex))
474             throw parse_error(lineno, "The timeout property requires an integer"
475                               " value");
476     } else if (name == "use.fs") {
477         // Deprecated; ignore it.
478     } else if (name.size() > 2 && name[0] == 'X' && name[1] == '-') {
479         // Any non-empty value is valid.
480     } else {
481         throw parse_error(lineno, "Unknown property '" + name + "'");
482     }
483 
484     md.insert(std::make_pair(name, value));
485 }
486 
487 void
488 detail::atf_tp_reader::read(void)
489 {
490     using tools::parser::parse_error;
491     using namespace atf_tp;
492 
493     std::pair< size_t, tools::parser::headers_map > hml =
494         tools::parser::read_headers(m_is, 1);
495     tools::parser::validate_content_type(hml.second,
496         "application/X-atf-tp", 1);
497 
498     tokenizer tkz(m_is, hml.first);
499     tools::parser::parser< tokenizer > p(tkz);
500 
501     try {
502         tools::parser::token t = p.expect(text_type, "property name");
503         if (t.text() != "ident")
504             throw parse_error(t.lineno(), "First property of a test case "
505                               "must be 'ident'");
506 
507         std::map< std::string, std::string > props;
508         do {
509             const std::string name = t.text();
510             t = p.expect(colon_type, "`:'");
511             const std::string value = tools::text::trim(p.rest_of_line());
512             t = p.expect(nl_type, "new line");
513             validate_and_insert(name, value, t.lineno(), props);
514 
515             t = p.expect(eof_type, nl_type, text_type, "property name, new "
516                          "line or eof");
517             if (t.type() == nl_type || t.type() == eof_type) {
518                 const std::map< std::string, std::string >::const_iterator
519                     iter = props.find("ident");
520                 if (iter == props.end())
521                     throw parse_error(t.lineno(), "Test case definition did "
522                                       "not define an 'ident' property");
523                 ATF_PARSER_CALLBACK(p, got_tc((*iter).second, props));
524                 props.clear();
525 
526                 if (t.type() == nl_type) {
527                     t = p.expect(text_type, "property name");
528                     if (t.text() != "ident")
529                         throw parse_error(t.lineno(), "First property of a "
530                                           "test case must be 'ident'");
531                 }
532             }
533         } while (t.type() != eof_type);
534         ATF_PARSER_CALLBACK(p, got_eof());
535     } catch (const parse_error& pe) {
536         p.add_error(pe);
537         p.reset(nl_type);
538     }
539 }
540 
541 impl::test_case_result
542 detail::parse_test_case_result(const std::string& line)
543 {
544     std::string state, arg, reason;
545     tokenize_result(line, state, arg, reason);
546 
547     if (state == "expected_death")
548         return handle_result_with_reason(state, arg, reason);
549     else if (state.compare(0, 13, "expected_exit") == 0)
550         return handle_result_with_reason_and_arg(state, arg, reason);
551     else if (state.compare(0, 16, "expected_failure") == 0)
552         return handle_result_with_reason(state, arg, reason);
553     else if (state.compare(0, 15, "expected_signal") == 0)
554         return handle_result_with_reason_and_arg(state, arg, reason);
555     else if (state.compare(0, 16, "expected_timeout") == 0)
556         return handle_result_with_reason(state, arg, reason);
557     else if (state == "failed")
558         return handle_result_with_reason(state, arg, reason);
559     else if (state == "passed")
560         return handle_result(state, arg, reason);
561     else if (state == "skipped")
562         return handle_result_with_reason(state, arg, reason);
563     else
564         throw std::runtime_error("Unknown test case result type in: " + line);
565 }
566 
567 impl::atf_tps_writer::atf_tps_writer(std::ostream& os) :
568     m_os(os)
569 {
570     tools::parser::headers_map hm;
571     tools::parser::attrs_map ct_attrs;
572     ct_attrs["version"] = "3";
573     hm["Content-Type"] =
574         tools::parser::header_entry("Content-Type", "application/X-atf-tps",
575                                   ct_attrs);
576     tools::parser::write_headers(hm, m_os);
577 }
578 
579 void
580 impl::atf_tps_writer::info(const std::string& what, const std::string& val)
581 {
582     m_os << "info: " << what << ", " << val << "\n";
583     m_os.flush();
584 }
585 
586 void
587 impl::atf_tps_writer::ntps(size_t p_ntps)
588 {
589     m_os << "tps-count: " << p_ntps << "\n";
590     m_os.flush();
591 }
592 
593 void
594 impl::atf_tps_writer::start_tp(const std::string& tp, size_t ntcs)
595 {
596     m_tpname = tp;
597     m_os << "tp-start: " << generate_timestamp() << ", " << tp << ", "
598          << ntcs << "\n";
599     m_os.flush();
600 }
601 
602 void
603 impl::atf_tps_writer::end_tp(const std::string& reason)
604 {
605     assert(reason.find('\n') == std::string::npos);
606     if (reason.empty())
607         m_os << "tp-end: " << generate_timestamp() << ", " << m_tpname << "\n";
608     else
609         m_os << "tp-end: " << generate_timestamp() << ", " << m_tpname
610              << ", " << reason << "\n";
611     m_os.flush();
612 }
613 
614 void
615 impl::atf_tps_writer::start_tc(const std::string& tcname)
616 {
617     m_tcname = tcname;
618     m_os << "tc-start: " << generate_timestamp() << ", " << tcname << "\n";
619     m_os.flush();
620 }
621 
622 void
623 impl::atf_tps_writer::stdout_tc(const std::string& line)
624 {
625     m_os << "tc-so:" << line << "\n";
626     check_stream(m_os);
627     m_os.flush();
628     check_stream(m_os);
629 }
630 
631 void
632 impl::atf_tps_writer::stderr_tc(const std::string& line)
633 {
634     m_os << "tc-se:" << line << "\n";
635     check_stream(m_os);
636     m_os.flush();
637     check_stream(m_os);
638 }
639 
640 void
641 impl::atf_tps_writer::end_tc(const std::string& state,
642                              const std::string& reason)
643 {
644     std::string str =  ", " + m_tcname + ", " + state;
645     if (!reason.empty())
646         str += ", " + reason;
647     m_os << "tc-end: " << generate_timestamp() << str << "\n";
648     m_os.flush();
649 }
650 
651 impl::metadata
652 impl::get_metadata(const tools::fs::path& executable,
653                    const vars_map& config)
654 {
655     get_metadata_params params(executable, config);
656     tools::process::child child =
657         tools::process::fork(get_metadata_child,
658                            tools::process::stream_capture(),
659                            tools::process::stream_inherit(),
660                            static_cast< void * >(&params));
661 
662     tools::io::pistream outin(child.stdout_fd());
663 
664     metadata_reader parser(outin);
665     parser.read();
666 
667     const tools::process::status status = child.wait();
668     if (!status.exited() || status.exitstatus() != EXIT_SUCCESS)
669         throw tools::parser::format_error("Test program returned failure "
670                                         "exit status for test case list");
671 
672     return metadata(parser.get_tcs());
673 }
674 
675 impl::test_case_result
676 impl::read_test_case_result(const tools::fs::path& results_path)
677 {
678     std::ifstream results_file(results_path.c_str());
679     if (!results_file)
680         throw std::runtime_error("Failed to open " + results_path.str());
681 
682     std::string line, extra_line;
683     std::getline(results_file, line);
684     if (!results_file.good())
685         throw std::runtime_error("Results file is empty");
686 
687     while (std::getline(results_file, extra_line).good())
688         line += "<<NEWLINE UNEXPECTED>>" + extra_line;
689 
690     results_file.close();
691 
692     return detail::parse_test_case_result(line);
693 }
694 
695 namespace {
696 
697 static volatile bool terminate_poll;
698 
699 static void
700 sigchld_handler(const int signo __attribute__((__unused__)))
701 {
702     terminate_poll = true;
703 }
704 
705 class child_muxer : public tools::io::muxer {
706     impl::atf_tps_writer& m_writer;
707 
708     void
709     line_callback(const size_t index, const std::string& line)
710     {
711         switch (index) {
712         case 0: m_writer.stdout_tc(line); break;
713         case 1: m_writer.stderr_tc(line); break;
714         default: std::abort();
715         }
716     }
717 
718 public:
719     child_muxer(const int* fds, const size_t nfds,
720                 impl::atf_tps_writer& writer) :
721         muxer(fds, nfds),
722         m_writer(writer)
723     {
724     }
725 };
726 
727 } // anonymous namespace
728 
729 std::pair< std::string, tools::process::status >
730 impl::run_test_case(const tools::fs::path& executable,
731                     const std::string& test_case_name,
732                     const std::string& test_case_part,
733                     const vars_map& metadata,
734                     const vars_map& config,
735                     const tools::fs::path& resfile,
736                     const tools::fs::path& workdir,
737                     atf_tps_writer& writer)
738 {
739     // TODO: Capture termination signals and deliver them to the subprocess
740     // instead.  Or maybe do something else; think about it.
741 
742     test_case_params params(executable, test_case_name, test_case_part,
743                             metadata, config, resfile, workdir);
744     tools::process::child child =
745         tools::process::fork(run_test_case_child,
746                            tools::process::stream_capture(),
747                            tools::process::stream_capture(),
748                            static_cast< void * >(&params));
749 
750     terminate_poll = false;
751 
752     const vars_map::const_iterator iter = metadata.find("timeout");
753     assert(iter != metadata.end());
754     const unsigned int timeout =
755         tools::text::to_type< unsigned int >((*iter).second);
756     const pid_t child_pid = child.pid();
757 
758     // Get the input stream of stdout and stderr.
759     tools::io::file_handle outfh = child.stdout_fd();
760     tools::io::file_handle errfh = child.stderr_fd();
761 
762     bool timed_out = false;
763 
764     // Process the test case's output and multiplex it into our output
765     // stream as we read it.
766     int fds[2] = {outfh.get(), errfh.get()};
767     child_muxer mux(fds, 2, writer);
768     try {
769         timers::child_timer timeout_timer(timeout, child_pid, terminate_poll);
770         signals::signal_programmer sigchld(SIGCHLD, sigchld_handler);
771         mux.mux(terminate_poll);
772         timed_out = timeout_timer.fired();
773     } catch (...) {
774         std::abort();
775     }
776 
777     ::killpg(child_pid, SIGKILL);
778     mux.flush();
779     tools::process::status status = child.wait();
780 
781     std::string reason;
782 
783     if (timed_out) {
784         // Don't assume the child process has been signaled due to the timeout
785         // expiration as older versions did.  The child process may have exited
786         // but we may have timed out due to a subchild process getting stuck.
787         reason = "Test case timed out after " + tools::text::to_string(timeout) +
788             " " + (timeout == 1 ? "second" : "seconds");
789     }
790 
791     return std::make_pair(reason, status);
792 }
793