1 //===-- Host.cpp ------------------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/lldb-python.h"
11 
12 // C includes
13 #include <errno.h>
14 #include <limits.h>
15 #include <stdlib.h>
16 #include <sys/types.h>
17 #ifndef _WIN32
18 #include <unistd.h>
19 #include <dlfcn.h>
20 #include <grp.h>
21 #include <netdb.h>
22 #include <pwd.h>
23 #include <sys/stat.h>
24 #endif
25 
26 #if defined (__APPLE__)
27 #include <mach/mach_port.h>
28 #include <mach/mach_init.h>
29 #include <mach-o/dyld.h>
30 #endif
31 
32 #if defined (__linux__) || defined (__FreeBSD__) || defined (__FreeBSD_kernel__) || defined (__APPLE__) || defined(__NetBSD__)
33 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
34 #include <spawn.h>
35 #endif
36 #include <sys/wait.h>
37 #include <sys/syscall.h>
38 #endif
39 
40 #if defined (__FreeBSD__)
41 #include <pthread_np.h>
42 #endif
43 
44 // C++ includes
45 #include <limits>
46 
47 #include "lldb/Host/FileSystem.h"
48 #include "lldb/Host/Host.h"
49 #include "lldb/Host/HostInfo.h"
50 #include "lldb/Core/ArchSpec.h"
51 #include "lldb/Core/Debugger.h"
52 #include "lldb/Core/Error.h"
53 #include "lldb/Core/Log.h"
54 #include "lldb/Core/Module.h"
55 #include "lldb/Host/FileSpec.h"
56 #include "lldb/Host/HostProcess.h"
57 #include "lldb/Host/MonitoringProcessLauncher.h"
58 #include "lldb/Host/ProcessLauncher.h"
59 #include "lldb/Host/ThreadLauncher.h"
60 #include "lldb/lldb-private-forward.h"
61 #include "lldb/Target/FileAction.h"
62 #include "lldb/Target/ProcessLaunchInfo.h"
63 #include "lldb/Target/TargetList.h"
64 #include "lldb/Utility/CleanUp.h"
65 
66 #if defined(_WIN32)
67 #include "lldb/Host/windows/ProcessLauncherWindows.h"
68 #else
69 #include "lldb/Host/posix/ProcessLauncherPosix.h"
70 #endif
71 
72 #if defined (__APPLE__)
73 #ifndef _POSIX_SPAWN_DISABLE_ASLR
74 #define _POSIX_SPAWN_DISABLE_ASLR       0x0100
75 #endif
76 
77 extern "C"
78 {
79     int __pthread_chdir(const char *path);
80     int __pthread_fchdir (int fildes);
81 }
82 
83 #endif
84 
85 using namespace lldb;
86 using namespace lldb_private;
87 
88 #if !defined (__APPLE__) && !defined (_WIN32)
89 struct MonitorInfo
90 {
91     lldb::pid_t pid;                            // The process ID to monitor
92     Host::MonitorChildProcessCallback callback; // The callback function to call when "pid" exits or signals
93     void *callback_baton;                       // The callback baton for the callback function
94     bool monitor_signals;                       // If true, call the callback when "pid" gets signaled.
95 };
96 
97 static thread_result_t
98 MonitorChildProcessThreadFunction (void *arg);
99 
100 HostThread
101 Host::StartMonitoringChildProcess(Host::MonitorChildProcessCallback callback, void *callback_baton, lldb::pid_t pid, bool monitor_signals)
102 {
103     MonitorInfo * info_ptr = new MonitorInfo();
104 
105     info_ptr->pid = pid;
106     info_ptr->callback = callback;
107     info_ptr->callback_baton = callback_baton;
108     info_ptr->monitor_signals = monitor_signals;
109 
110     char thread_name[256];
111     ::snprintf(thread_name, sizeof(thread_name), "<lldb.host.wait4(pid=%" PRIu64 ")>", pid);
112     return ThreadLauncher::LaunchThread(thread_name, MonitorChildProcessThreadFunction, info_ptr, NULL);
113 }
114 
115 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
116 //------------------------------------------------------------------
117 // Scoped class that will disable thread canceling when it is
118 // constructed, and exception safely restore the previous value it
119 // when it goes out of scope.
120 //------------------------------------------------------------------
121 class ScopedPThreadCancelDisabler
122 {
123 public:
124     ScopedPThreadCancelDisabler()
125     {
126         // Disable the ability for this thread to be cancelled
127         int err = ::pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &m_old_state);
128         if (err != 0)
129             m_old_state = -1;
130     }
131 
132     ~ScopedPThreadCancelDisabler()
133     {
134         // Restore the ability for this thread to be cancelled to what it
135         // previously was.
136         if (m_old_state != -1)
137             ::pthread_setcancelstate (m_old_state, 0);
138     }
139 private:
140     int m_old_state;    // Save the old cancelability state.
141 };
142 #endif // __ANDROID_NDK__
143 
144 static thread_result_t
145 MonitorChildProcessThreadFunction (void *arg)
146 {
147     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
148     const char *function = __FUNCTION__;
149     if (log)
150         log->Printf ("%s (arg = %p) thread starting...", function, arg);
151 
152     MonitorInfo *info = (MonitorInfo *)arg;
153 
154     const Host::MonitorChildProcessCallback callback = info->callback;
155     void * const callback_baton = info->callback_baton;
156     const bool monitor_signals = info->monitor_signals;
157 
158     assert (info->pid <= UINT32_MAX);
159     const ::pid_t pid = monitor_signals ? -1 * getpgid(info->pid) : info->pid;
160 
161     delete info;
162 
163     int status = -1;
164 #if defined (__FreeBSD__) || defined (__FreeBSD_kernel__)
165     #define __WALL 0
166 #endif
167     const int options = __WALL;
168 
169     while (1)
170     {
171         log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS);
172         if (log)
173             log->Printf("%s ::wait_pid (pid = %" PRIi32 ", &status, options = %i)...", function, pid, options);
174 
175         // Wait for all child processes
176 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
177         ::pthread_testcancel ();
178 #endif
179         // Get signals from all children with same process group of pid
180         const ::pid_t wait_pid = ::waitpid (pid, &status, options);
181 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
182         ::pthread_testcancel ();
183 #endif
184         if (wait_pid == -1)
185         {
186             if (errno == EINTR)
187                 continue;
188             else
189             {
190                 if (log)
191                     log->Printf ("%s (arg = %p) thread exiting because waitpid failed (%s)...", __FUNCTION__, arg, strerror(errno));
192                 break;
193             }
194         }
195         else if (wait_pid > 0)
196         {
197             bool exited = false;
198             int signal = 0;
199             int exit_status = 0;
200             const char *status_cstr = NULL;
201             if (WIFSTOPPED(status))
202             {
203                 signal = WSTOPSIG(status);
204                 status_cstr = "STOPPED";
205             }
206             else if (WIFEXITED(status))
207             {
208                 exit_status = WEXITSTATUS(status);
209                 status_cstr = "EXITED";
210                 exited = true;
211             }
212             else if (WIFSIGNALED(status))
213             {
214                 signal = WTERMSIG(status);
215                 status_cstr = "SIGNALED";
216                 if (wait_pid == abs(pid)) {
217                     exited = true;
218                     exit_status = -1;
219                 }
220             }
221             else
222             {
223                 status_cstr = "(\?\?\?)";
224             }
225 
226             // Scope for pthread_cancel_disabler
227             {
228 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
229                 ScopedPThreadCancelDisabler pthread_cancel_disabler;
230 #endif
231 
232                 log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS);
233                 if (log)
234                     log->Printf ("%s ::waitpid (pid = %" PRIi32 ", &status, options = %i) => pid = %" PRIi32 ", status = 0x%8.8x (%s), signal = %i, exit_state = %i",
235                                  function,
236                                  wait_pid,
237                                  options,
238                                  pid,
239                                  status,
240                                  status_cstr,
241                                  signal,
242                                  exit_status);
243 
244                 if (exited || (signal != 0 && monitor_signals))
245                 {
246                     bool callback_return = false;
247                     if (callback)
248                         callback_return = callback (callback_baton, wait_pid, exited, signal, exit_status);
249 
250                     // If our process exited, then this thread should exit
251                     if (exited && wait_pid == abs(pid))
252                     {
253                         if (log)
254                             log->Printf ("%s (arg = %p) thread exiting because pid received exit signal...", __FUNCTION__, arg);
255                         break;
256                     }
257                     // If the callback returns true, it means this process should
258                     // exit
259                     if (callback_return)
260                     {
261                         if (log)
262                             log->Printf ("%s (arg = %p) thread exiting because callback returned true...", __FUNCTION__, arg);
263                         break;
264                     }
265                 }
266             }
267         }
268     }
269 
270     log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS);
271     if (log)
272         log->Printf ("%s (arg = %p) thread exiting...", __FUNCTION__, arg);
273 
274     return NULL;
275 }
276 
277 #endif // #if !defined (__APPLE__) && !defined (_WIN32)
278 
279 #if !defined (__APPLE__)
280 
281 void
282 Host::SystemLog (SystemLogType type, const char *format, va_list args)
283 {
284     vfprintf (stderr, format, args);
285 }
286 
287 #endif
288 
289 void
290 Host::SystemLog (SystemLogType type, const char *format, ...)
291 {
292     va_list args;
293     va_start (args, format);
294     SystemLog (type, format, args);
295     va_end (args);
296 }
297 
298 lldb::pid_t
299 Host::GetCurrentProcessID()
300 {
301     return ::getpid();
302 }
303 
304 #ifndef _WIN32
305 
306 lldb::tid_t
307 Host::GetCurrentThreadID()
308 {
309 #if defined (__APPLE__)
310     // Calling "mach_thread_self()" bumps the reference count on the thread
311     // port, so we need to deallocate it. mach_task_self() doesn't bump the ref
312     // count.
313     thread_port_t thread_self = mach_thread_self();
314     mach_port_deallocate(mach_task_self(), thread_self);
315     return thread_self;
316 #elif defined(__FreeBSD__)
317     return lldb::tid_t(pthread_getthreadid_np());
318 #elif defined(__ANDROID_NDK__)
319     return lldb::tid_t(gettid());
320 #elif defined(__linux__)
321     return lldb::tid_t(syscall(SYS_gettid));
322 #else
323     return lldb::tid_t(pthread_self());
324 #endif
325 }
326 
327 lldb::thread_t
328 Host::GetCurrentThread ()
329 {
330     return lldb::thread_t(pthread_self());
331 }
332 
333 const char *
334 Host::GetSignalAsCString (int signo)
335 {
336     switch (signo)
337     {
338     case SIGHUP:    return "SIGHUP";    // 1    hangup
339     case SIGINT:    return "SIGINT";    // 2    interrupt
340     case SIGQUIT:   return "SIGQUIT";   // 3    quit
341     case SIGILL:    return "SIGILL";    // 4    illegal instruction (not reset when caught)
342     case SIGTRAP:   return "SIGTRAP";   // 5    trace trap (not reset when caught)
343     case SIGABRT:   return "SIGABRT";   // 6    abort()
344 #if  defined(SIGPOLL)
345 #if !defined(SIGIO) || (SIGPOLL != SIGIO)
346 // Under some GNU/Linux, SIGPOLL and SIGIO are the same. Causing the build to
347 // fail with 'multiple define cases with same value'
348     case SIGPOLL:   return "SIGPOLL";   // 7    pollable event ([XSR] generated, not supported)
349 #endif
350 #endif
351 #if  defined(SIGEMT)
352     case SIGEMT:    return "SIGEMT";    // 7    EMT instruction
353 #endif
354     case SIGFPE:    return "SIGFPE";    // 8    floating point exception
355     case SIGKILL:   return "SIGKILL";   // 9    kill (cannot be caught or ignored)
356     case SIGBUS:    return "SIGBUS";    // 10    bus error
357     case SIGSEGV:   return "SIGSEGV";   // 11    segmentation violation
358     case SIGSYS:    return "SIGSYS";    // 12    bad argument to system call
359     case SIGPIPE:   return "SIGPIPE";   // 13    write on a pipe with no one to read it
360     case SIGALRM:   return "SIGALRM";   // 14    alarm clock
361     case SIGTERM:   return "SIGTERM";   // 15    software termination signal from kill
362     case SIGURG:    return "SIGURG";    // 16    urgent condition on IO channel
363     case SIGSTOP:   return "SIGSTOP";   // 17    sendable stop signal not from tty
364     case SIGTSTP:   return "SIGTSTP";   // 18    stop signal from tty
365     case SIGCONT:   return "SIGCONT";   // 19    continue a stopped process
366     case SIGCHLD:   return "SIGCHLD";   // 20    to parent on child stop or exit
367     case SIGTTIN:   return "SIGTTIN";   // 21    to readers pgrp upon background tty read
368     case SIGTTOU:   return "SIGTTOU";   // 22    like TTIN for output if (tp->t_local&LTOSTOP)
369 #if  defined(SIGIO)
370     case SIGIO:     return "SIGIO";     // 23    input/output possible signal
371 #endif
372     case SIGXCPU:   return "SIGXCPU";   // 24    exceeded CPU time limit
373     case SIGXFSZ:   return "SIGXFSZ";   // 25    exceeded file size limit
374     case SIGVTALRM: return "SIGVTALRM"; // 26    virtual time alarm
375     case SIGPROF:   return "SIGPROF";   // 27    profiling time alarm
376 #if  defined(SIGWINCH)
377     case SIGWINCH:  return "SIGWINCH";  // 28    window size changes
378 #endif
379 #if  defined(SIGINFO)
380     case SIGINFO:   return "SIGINFO";   // 29    information request
381 #endif
382     case SIGUSR1:   return "SIGUSR1";   // 30    user defined signal 1
383     case SIGUSR2:   return "SIGUSR2";   // 31    user defined signal 2
384     default:
385         break;
386     }
387     return NULL;
388 }
389 
390 #endif
391 
392 void
393 Host::WillTerminate ()
394 {
395 }
396 
397 #if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined (__FreeBSD_kernel__) && !defined (__linux__) // see macosx/Host.mm
398 
399 void
400 Host::Backtrace (Stream &strm, uint32_t max_frames)
401 {
402     // TODO: Is there a way to backtrace the current process on other systems?
403 }
404 
405 size_t
406 Host::GetEnvironment (StringList &env)
407 {
408     // TODO: Is there a way to the host environment for this process on other systems?
409     return 0;
410 }
411 
412 #endif // #if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined (__FreeBSD_kernel__) && !defined (__linux__)
413 
414 #ifndef _WIN32
415 
416 lldb::thread_key_t
417 Host::ThreadLocalStorageCreate(ThreadLocalStorageCleanupCallback callback)
418 {
419     pthread_key_t key;
420     ::pthread_key_create (&key, callback);
421     return key;
422 }
423 
424 void*
425 Host::ThreadLocalStorageGet(lldb::thread_key_t key)
426 {
427     return ::pthread_getspecific (key);
428 }
429 
430 void
431 Host::ThreadLocalStorageSet(lldb::thread_key_t key, void *value)
432 {
433    ::pthread_setspecific (key, value);
434 }
435 
436 #endif
437 
438 #if !defined (__APPLE__) // see Host.mm
439 
440 bool
441 Host::GetBundleDirectory (const FileSpec &file, FileSpec &bundle)
442 {
443     bundle.Clear();
444     return false;
445 }
446 
447 bool
448 Host::ResolveExecutableInBundle (FileSpec &file)
449 {
450     return false;
451 }
452 #endif
453 
454 #ifndef _WIN32
455 
456 FileSpec
457 Host::GetModuleFileSpecForHostAddress (const void *host_addr)
458 {
459     FileSpec module_filespec;
460 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
461     Dl_info info;
462     if (::dladdr (host_addr, &info))
463     {
464         if (info.dli_fname)
465             module_filespec.SetFile(info.dli_fname, true);
466     }
467 #else
468     assert(false && "dladdr() not supported on Android");
469 #endif
470     return module_filespec;
471 }
472 
473 #endif
474 
475 #if !defined(__linux__)
476 bool
477 Host::FindProcessThreads (const lldb::pid_t pid, TidMap &tids_to_attach)
478 {
479     return false;
480 }
481 #endif
482 
483 struct ShellInfo
484 {
485     ShellInfo () :
486         process_reaped (false),
487         can_delete (false),
488         pid (LLDB_INVALID_PROCESS_ID),
489         signo(-1),
490         status(-1)
491     {
492     }
493 
494     lldb_private::Predicate<bool> process_reaped;
495     lldb_private::Predicate<bool> can_delete;
496     lldb::pid_t pid;
497     int signo;
498     int status;
499 };
500 
501 static bool
502 MonitorShellCommand (void *callback_baton,
503                      lldb::pid_t pid,
504                      bool exited,       // True if the process did exit
505                      int signo,         // Zero for no signal
506                      int status)   // Exit value of process if signal is zero
507 {
508     ShellInfo *shell_info = (ShellInfo *)callback_baton;
509     shell_info->pid = pid;
510     shell_info->signo = signo;
511     shell_info->status = status;
512     // Let the thread running Host::RunShellCommand() know that the process
513     // exited and that ShellInfo has been filled in by broadcasting to it
514     shell_info->process_reaped.SetValue(1, eBroadcastAlways);
515     // Now wait for a handshake back from that thread running Host::RunShellCommand
516     // so we know that we can delete shell_info_ptr
517     shell_info->can_delete.WaitForValueEqualTo(true);
518     // Sleep a bit to allow the shell_info->can_delete.SetValue() to complete...
519     usleep(1000);
520     // Now delete the shell info that was passed into this function
521     delete shell_info;
522     return true;
523 }
524 
525 Error
526 Host::RunShellCommand (const char *command,
527                        const char *working_dir,
528                        int *status_ptr,
529                        int *signo_ptr,
530                        std::string *command_output_ptr,
531                        uint32_t timeout_sec,
532                        bool run_in_default_shell)
533 {
534     Error error;
535     ProcessLaunchInfo launch_info;
536     launch_info.SetArchitecture(HostInfo::GetArchitecture());
537     if (run_in_default_shell)
538     {
539         // Run the command in a shell
540         launch_info.SetShell(HostInfo::GetDefaultShell());
541         launch_info.GetArguments().AppendArgument(command);
542         const bool localhost = true;
543         const bool will_debug = false;
544         const bool first_arg_is_full_shell_command = true;
545         launch_info.ConvertArgumentsForLaunchingInShell (error,
546                                                          localhost,
547                                                          will_debug,
548                                                          first_arg_is_full_shell_command,
549                                                          0);
550     }
551     else
552     {
553         // No shell, just run it
554         Args args (command);
555         const bool first_arg_is_executable = true;
556         launch_info.SetArguments(args, first_arg_is_executable);
557     }
558 
559     if (working_dir)
560         launch_info.SetWorkingDirectory(working_dir);
561     llvm::SmallString<PATH_MAX> output_file_path;
562 
563     if (command_output_ptr)
564     {
565         // Create a temporary file to get the stdout/stderr and redirect the
566         // output of the command into this file. We will later read this file
567         // if all goes well and fill the data into "command_output_ptr"
568         FileSpec tmpdir_file_spec;
569         if (HostInfo::GetLLDBPath(ePathTypeLLDBTempSystemDir, tmpdir_file_spec))
570         {
571             tmpdir_file_spec.AppendPathComponent("lldb-shell-output.%%%%%%");
572             llvm::sys::fs::createUniqueFile(tmpdir_file_spec.GetPath().c_str(), output_file_path);
573         }
574         else
575         {
576             llvm::sys::fs::createTemporaryFile("lldb-shell-output.%%%%%%", "", output_file_path);
577         }
578     }
579 
580     launch_info.AppendSuppressFileAction (STDIN_FILENO, true, false);
581     if (!output_file_path.empty())
582     {
583         launch_info.AppendOpenFileAction(STDOUT_FILENO, output_file_path.c_str(), false, true);
584         launch_info.AppendDuplicateFileAction(STDOUT_FILENO, STDERR_FILENO);
585     }
586     else
587     {
588         launch_info.AppendSuppressFileAction (STDOUT_FILENO, false, true);
589         launch_info.AppendSuppressFileAction (STDERR_FILENO, false, true);
590     }
591 
592     // The process monitor callback will delete the 'shell_info_ptr' below...
593     std::unique_ptr<ShellInfo> shell_info_ap (new ShellInfo());
594 
595     const bool monitor_signals = false;
596     launch_info.SetMonitorProcessCallback(MonitorShellCommand, shell_info_ap.get(), monitor_signals);
597 
598     error = LaunchProcess (launch_info);
599     const lldb::pid_t pid = launch_info.GetProcessID();
600 
601     if (error.Success() && pid == LLDB_INVALID_PROCESS_ID)
602         error.SetErrorString("failed to get process ID");
603 
604     if (error.Success())
605     {
606         // The process successfully launched, so we can defer ownership of
607         // "shell_info" to the MonitorShellCommand callback function that will
608         // get called when the process dies. We release the unique pointer as it
609         // doesn't need to delete the ShellInfo anymore.
610         ShellInfo *shell_info = shell_info_ap.release();
611         TimeValue *timeout_ptr = nullptr;
612         TimeValue timeout_time(TimeValue::Now());
613         if (timeout_sec > 0) {
614             timeout_time.OffsetWithSeconds(timeout_sec);
615             timeout_ptr = &timeout_time;
616         }
617         bool timed_out = false;
618         shell_info->process_reaped.WaitForValueEqualTo(true, timeout_ptr, &timed_out);
619         if (timed_out)
620         {
621             error.SetErrorString("timed out waiting for shell command to complete");
622 
623             // Kill the process since it didn't complete within the timeout specified
624             Kill (pid, SIGKILL);
625             // Wait for the monitor callback to get the message
626             timeout_time = TimeValue::Now();
627             timeout_time.OffsetWithSeconds(1);
628             timed_out = false;
629             shell_info->process_reaped.WaitForValueEqualTo(true, &timeout_time, &timed_out);
630         }
631         else
632         {
633             if (status_ptr)
634                 *status_ptr = shell_info->status;
635 
636             if (signo_ptr)
637                 *signo_ptr = shell_info->signo;
638 
639             if (command_output_ptr)
640             {
641                 command_output_ptr->clear();
642                 FileSpec file_spec(output_file_path.c_str(), File::eOpenOptionRead);
643                 uint64_t file_size = file_spec.GetByteSize();
644                 if (file_size > 0)
645                 {
646                     if (file_size > command_output_ptr->max_size())
647                     {
648                         error.SetErrorStringWithFormat("shell command output is too large to fit into a std::string");
649                     }
650                     else
651                     {
652                         command_output_ptr->resize(file_size);
653                         file_spec.ReadFileContents(0, &((*command_output_ptr)[0]), command_output_ptr->size(), &error);
654                     }
655                 }
656             }
657         }
658         shell_info->can_delete.SetValue(true, eBroadcastAlways);
659     }
660 
661     FileSpec output_file_spec(output_file_path.c_str(), false);
662     if (FileSystem::GetFileExists(output_file_spec))
663         FileSystem::Unlink(output_file_path.c_str());
664     // Handshake with the monitor thread, or just let it know in advance that
665     // it can delete "shell_info" in case we timed out and were not able to kill
666     // the process...
667     return error;
668 }
669 
670 
671 // LaunchProcessPosixSpawn for Apple, Linux, FreeBSD and other GLIBC
672 // systems
673 
674 #if defined (__APPLE__) || defined (__linux__) || defined (__FreeBSD__) || defined (__GLIBC__) || defined(__NetBSD__)
675 // this method needs to be visible to macosx/Host.cpp and
676 // common/Host.cpp.
677 
678 short
679 Host::GetPosixspawnFlags(const ProcessLaunchInfo &launch_info)
680 {
681 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
682     short flags = POSIX_SPAWN_SETSIGDEF | POSIX_SPAWN_SETSIGMASK;
683 
684 #if defined (__APPLE__)
685     if (launch_info.GetFlags().Test (eLaunchFlagExec))
686         flags |= POSIX_SPAWN_SETEXEC;           // Darwin specific posix_spawn flag
687 
688     if (launch_info.GetFlags().Test (eLaunchFlagDebug))
689         flags |= POSIX_SPAWN_START_SUSPENDED;   // Darwin specific posix_spawn flag
690 
691     if (launch_info.GetFlags().Test (eLaunchFlagDisableASLR))
692         flags |= _POSIX_SPAWN_DISABLE_ASLR;     // Darwin specific posix_spawn flag
693 
694     if (launch_info.GetLaunchInSeparateProcessGroup())
695         flags |= POSIX_SPAWN_SETPGROUP;
696 
697 #ifdef POSIX_SPAWN_CLOEXEC_DEFAULT
698 #if defined (__APPLE__) && (defined (__x86_64__) || defined (__i386__))
699     static LazyBool g_use_close_on_exec_flag = eLazyBoolCalculate;
700     if (g_use_close_on_exec_flag == eLazyBoolCalculate)
701     {
702         g_use_close_on_exec_flag = eLazyBoolNo;
703 
704         uint32_t major, minor, update;
705         if (HostInfo::GetOSVersion(major, minor, update))
706         {
707             // Kernel panic if we use the POSIX_SPAWN_CLOEXEC_DEFAULT on 10.7 or earlier
708             if (major > 10 || (major == 10 && minor > 7))
709             {
710                 // Only enable for 10.8 and later OS versions
711                 g_use_close_on_exec_flag = eLazyBoolYes;
712             }
713         }
714     }
715 #else
716     static LazyBool g_use_close_on_exec_flag = eLazyBoolYes;
717 #endif
718     // Close all files exception those with file actions if this is supported.
719     if (g_use_close_on_exec_flag == eLazyBoolYes)
720         flags |= POSIX_SPAWN_CLOEXEC_DEFAULT;
721 #endif
722 #endif // #if defined (__APPLE__)
723     return flags;
724 #else
725     assert(false && "Host::GetPosixspawnFlags() not supported on Android");
726     return 0;
727 #endif
728 }
729 
730 Error
731 Host::LaunchProcessPosixSpawn(const char *exe_path, const ProcessLaunchInfo &launch_info, lldb::pid_t &pid)
732 {
733     Error error;
734 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
735     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_HOST | LIBLLDB_LOG_PROCESS));
736 
737     posix_spawnattr_t attr;
738     error.SetError( ::posix_spawnattr_init (&attr), eErrorTypePOSIX);
739 
740     if (error.Fail() || log)
741         error.PutToLog(log, "::posix_spawnattr_init ( &attr )");
742     if (error.Fail())
743         return error;
744 
745     // Make a quick class that will cleanup the posix spawn attributes in case
746     // we return in the middle of this function.
747     lldb_utility::CleanUp <posix_spawnattr_t *, int> posix_spawnattr_cleanup(&attr, posix_spawnattr_destroy);
748 
749     sigset_t no_signals;
750     sigset_t all_signals;
751     sigemptyset (&no_signals);
752     sigfillset (&all_signals);
753     ::posix_spawnattr_setsigmask(&attr, &no_signals);
754 #if defined (__linux__)  || defined (__FreeBSD__)
755     ::posix_spawnattr_setsigdefault(&attr, &no_signals);
756 #else
757     ::posix_spawnattr_setsigdefault(&attr, &all_signals);
758 #endif
759 
760     short flags = GetPosixspawnFlags(launch_info);
761 
762     error.SetError( ::posix_spawnattr_setflags (&attr, flags), eErrorTypePOSIX);
763     if (error.Fail() || log)
764         error.PutToLog(log, "::posix_spawnattr_setflags ( &attr, flags=0x%8.8x )", flags);
765     if (error.Fail())
766         return error;
767 
768     // posix_spawnattr_setbinpref_np appears to be an Apple extension per:
769     // http://www.unix.com/man-page/OSX/3/posix_spawnattr_setbinpref_np/
770 #if defined (__APPLE__) && !defined (__arm__)
771 
772     // Don't set the binpref if a shell was provided.  After all, that's only going to affect what version of the shell
773     // is launched, not what fork of the binary is launched.  We insert "arch --arch <ARCH> as part of the shell invocation
774     // to do that job on OSX.
775 
776     if (launch_info.GetShell() == nullptr)
777     {
778         // We don't need to do this for ARM, and we really shouldn't now that we
779         // have multiple CPU subtypes and no posix_spawnattr call that allows us
780         // to set which CPU subtype to launch...
781         const ArchSpec &arch_spec = launch_info.GetArchitecture();
782         cpu_type_t cpu = arch_spec.GetMachOCPUType();
783         cpu_type_t sub = arch_spec.GetMachOCPUSubType();
784         if (cpu != 0 &&
785             cpu != static_cast<cpu_type_t>(UINT32_MAX) &&
786             cpu != static_cast<cpu_type_t>(LLDB_INVALID_CPUTYPE) &&
787             !(cpu == 0x01000007 && sub == 8)) // If haswell is specified, don't try to set the CPU type or we will fail
788         {
789             size_t ocount = 0;
790             error.SetError( ::posix_spawnattr_setbinpref_np (&attr, 1, &cpu, &ocount), eErrorTypePOSIX);
791             if (error.Fail() || log)
792                 error.PutToLog(log, "::posix_spawnattr_setbinpref_np ( &attr, 1, cpu_type = 0x%8.8x, count => %llu )", cpu, (uint64_t)ocount);
793 
794             if (error.Fail() || ocount != 1)
795                 return error;
796         }
797     }
798 
799 #endif
800 
801     const char *tmp_argv[2];
802     char * const *argv = (char * const*)launch_info.GetArguments().GetConstArgumentVector();
803     char * const *envp = (char * const*)launch_info.GetEnvironmentEntries().GetConstArgumentVector();
804     if (argv == NULL)
805     {
806         // posix_spawn gets very unhappy if it doesn't have at least the program
807         // name in argv[0]. One of the side affects I have noticed is the environment
808         // variables don't make it into the child process if "argv == NULL"!!!
809         tmp_argv[0] = exe_path;
810         tmp_argv[1] = NULL;
811         argv = (char * const*)tmp_argv;
812     }
813 
814 #if !defined (__APPLE__)
815     // manage the working directory
816     char current_dir[PATH_MAX];
817     current_dir[0] = '\0';
818 #endif
819 
820     const char *working_dir = launch_info.GetWorkingDirectory();
821     if (working_dir)
822     {
823 #if defined (__APPLE__)
824         // Set the working directory on this thread only
825         if (__pthread_chdir (working_dir) < 0) {
826             if (errno == ENOENT) {
827                 error.SetErrorStringWithFormat("No such file or directory: %s", working_dir);
828             } else if (errno == ENOTDIR) {
829                 error.SetErrorStringWithFormat("Path doesn't name a directory: %s", working_dir);
830             } else {
831                 error.SetErrorStringWithFormat("An unknown error occurred when changing directory for process execution.");
832             }
833             return error;
834         }
835 #else
836         if (::getcwd(current_dir, sizeof(current_dir)) == NULL)
837         {
838             error.SetError(errno, eErrorTypePOSIX);
839             error.LogIfError(log, "unable to save the current directory");
840             return error;
841         }
842 
843         if (::chdir(working_dir) == -1)
844         {
845             error.SetError(errno, eErrorTypePOSIX);
846             error.LogIfError(log, "unable to change working directory to %s", working_dir);
847             return error;
848         }
849 #endif
850     }
851 
852     ::pid_t result_pid = LLDB_INVALID_PROCESS_ID;
853     const size_t num_file_actions = launch_info.GetNumFileActions ();
854     if (num_file_actions > 0)
855     {
856         posix_spawn_file_actions_t file_actions;
857         error.SetError( ::posix_spawn_file_actions_init (&file_actions), eErrorTypePOSIX);
858         if (error.Fail() || log)
859             error.PutToLog(log, "::posix_spawn_file_actions_init ( &file_actions )");
860         if (error.Fail())
861             return error;
862 
863         // Make a quick class that will cleanup the posix spawn attributes in case
864         // we return in the middle of this function.
865         lldb_utility::CleanUp <posix_spawn_file_actions_t *, int> posix_spawn_file_actions_cleanup (&file_actions, posix_spawn_file_actions_destroy);
866 
867         for (size_t i=0; i<num_file_actions; ++i)
868         {
869             const FileAction *launch_file_action = launch_info.GetFileActionAtIndex(i);
870             if (launch_file_action)
871             {
872                 if (!AddPosixSpawnFileAction(&file_actions, launch_file_action, log, error))
873                     return error;
874             }
875         }
876 
877         error.SetError(::posix_spawnp(&result_pid, exe_path, &file_actions, &attr, argv, envp), eErrorTypePOSIX);
878 
879         if (error.Fail() || log)
880         {
881             error.PutToLog(log, "::posix_spawnp ( pid => %i, path = '%s', file_actions = %p, attr = %p, argv = %p, envp = %p )", result_pid,
882                            exe_path, static_cast<void *>(&file_actions), static_cast<void *>(&attr), reinterpret_cast<const void *>(argv),
883                            reinterpret_cast<const void *>(envp));
884             if (log)
885             {
886                 for (int ii=0; argv[ii]; ++ii)
887                     log->Printf("argv[%i] = '%s'", ii, argv[ii]);
888             }
889         }
890 
891     }
892     else
893     {
894         error.SetError(::posix_spawnp(&result_pid, exe_path, NULL, &attr, argv, envp), eErrorTypePOSIX);
895 
896         if (error.Fail() || log)
897         {
898             error.PutToLog(log, "::posix_spawnp ( pid => %i, path = '%s', file_actions = NULL, attr = %p, argv = %p, envp = %p )",
899                            result_pid, exe_path, static_cast<void *>(&attr), reinterpret_cast<const void *>(argv),
900                            reinterpret_cast<const void *>(envp));
901             if (log)
902             {
903                 for (int ii=0; argv[ii]; ++ii)
904                     log->Printf("argv[%i] = '%s'", ii, argv[ii]);
905             }
906         }
907     }
908     pid = result_pid;
909 
910     if (working_dir)
911     {
912 #if defined (__APPLE__)
913         // No more thread specific current working directory
914         __pthread_fchdir (-1);
915 #else
916         if (::chdir(current_dir) == -1 && error.Success())
917         {
918             error.SetError(errno, eErrorTypePOSIX);
919             error.LogIfError(log, "unable to change current directory back to %s",
920                     current_dir);
921         }
922 #endif
923     }
924 #else
925     error.SetErrorString("Host::LaunchProcessPosixSpawn() not supported on Android");
926 #endif
927 
928     return error;
929 }
930 
931 bool
932 Host::AddPosixSpawnFileAction(void *_file_actions, const FileAction *info, Log *log, Error &error)
933 {
934 #if !defined(__ANDROID__) && !defined(__ANDROID_NDK__)
935     if (info == NULL)
936         return false;
937 
938     posix_spawn_file_actions_t *file_actions = reinterpret_cast<posix_spawn_file_actions_t *>(_file_actions);
939 
940     switch (info->GetAction())
941     {
942         case FileAction::eFileActionNone:
943             error.Clear();
944             break;
945 
946         case FileAction::eFileActionClose:
947             if (info->GetFD() == -1)
948                 error.SetErrorString("invalid fd for posix_spawn_file_actions_addclose(...)");
949             else
950             {
951                 error.SetError(::posix_spawn_file_actions_addclose(file_actions, info->GetFD()), eErrorTypePOSIX);
952                 if (log && (error.Fail() || log))
953                     error.PutToLog(log, "posix_spawn_file_actions_addclose (action=%p, fd=%i)",
954                                    static_cast<void *>(file_actions), info->GetFD());
955             }
956             break;
957 
958         case FileAction::eFileActionDuplicate:
959             if (info->GetFD() == -1)
960                 error.SetErrorString("invalid fd for posix_spawn_file_actions_adddup2(...)");
961             else if (info->GetActionArgument() == -1)
962                 error.SetErrorString("invalid duplicate fd for posix_spawn_file_actions_adddup2(...)");
963             else
964             {
965                 error.SetError(
966                     ::posix_spawn_file_actions_adddup2(file_actions, info->GetFD(), info->GetActionArgument()),
967                     eErrorTypePOSIX);
968                 if (log && (error.Fail() || log))
969                     error.PutToLog(log, "posix_spawn_file_actions_adddup2 (action=%p, fd=%i, dup_fd=%i)",
970                                    static_cast<void *>(file_actions), info->GetFD(), info->GetActionArgument());
971             }
972             break;
973 
974         case FileAction::eFileActionOpen:
975             if (info->GetFD() == -1)
976                 error.SetErrorString("invalid fd in posix_spawn_file_actions_addopen(...)");
977             else
978             {
979                 int oflag = info->GetActionArgument();
980 
981                 mode_t mode = 0;
982 
983                 if (oflag & O_CREAT)
984                     mode = 0640;
985 
986                 error.SetError(
987                     ::posix_spawn_file_actions_addopen(file_actions, info->GetFD(), info->GetPath(), oflag, mode),
988                     eErrorTypePOSIX);
989                 if (error.Fail() || log)
990                     error.PutToLog(log,
991                                    "posix_spawn_file_actions_addopen (action=%p, fd=%i, path='%s', oflag=%i, mode=%i)",
992                                    static_cast<void *>(file_actions), info->GetFD(), info->GetPath(), oflag, mode);
993             }
994             break;
995     }
996     return error.Success();
997 #else
998     error.SetErrorString("Host::AddPosixSpawnFileAction() not supported on Android");
999     return false;
1000 #endif
1001 }
1002 #endif // LaunchProcedssPosixSpawn: Apple, Linux, FreeBSD and other GLIBC systems
1003 
1004 #if defined(__linux__) || defined(__FreeBSD__) || defined(__GLIBC__) || defined(__NetBSD__) || defined(_WIN32)
1005 // The functions below implement process launching via posix_spawn() for Linux,
1006 // FreeBSD and NetBSD.
1007 
1008 Error
1009 Host::LaunchProcess (ProcessLaunchInfo &launch_info)
1010 {
1011     std::unique_ptr<ProcessLauncher> delegate_launcher;
1012 #if defined(_WIN32)
1013     delegate_launcher.reset(new ProcessLauncherWindows());
1014 #else
1015     delegate_launcher.reset(new ProcessLauncherPosix());
1016 #endif
1017     MonitoringProcessLauncher launcher(std::move(delegate_launcher));
1018 
1019     Error error;
1020     HostProcess process = launcher.LaunchProcess(launch_info, error);
1021 
1022     // TODO(zturner): It would be better if the entire HostProcess were returned instead of writing
1023     // it into this structure.
1024     launch_info.SetProcessID(process.GetProcessId());
1025 
1026     return error;
1027 }
1028 #endif // defined(__linux__) || defined(__FreeBSD__) || defined(__NetBSD__)
1029 
1030 #ifndef _WIN32
1031 void
1032 Host::Kill(lldb::pid_t pid, int signo)
1033 {
1034     ::kill(pid, signo);
1035 }
1036 
1037 #endif
1038 
1039 #if !defined (__APPLE__)
1040 bool
1041 Host::OpenFileInExternalEditor (const FileSpec &file_spec, uint32_t line_no)
1042 {
1043     return false;
1044 }
1045 
1046 void
1047 Host::SetCrashDescriptionWithFormat (const char *format, ...)
1048 {
1049 }
1050 
1051 void
1052 Host::SetCrashDescription (const char *description)
1053 {
1054 }
1055 
1056 lldb::pid_t
1057 Host::LaunchApplication (const FileSpec &app_file_spec)
1058 {
1059     return LLDB_INVALID_PROCESS_ID;
1060 }
1061 
1062 #endif
1063 
1064 #if !defined (__linux__) && !defined (__FreeBSD__) && !defined (__NetBSD__)
1065 
1066 const lldb_private::UnixSignalsSP&
1067 Host::GetUnixSignals ()
1068 {
1069     static UnixSignalsSP s_unix_signals_sp (new UnixSignals ());
1070     return s_unix_signals_sp;
1071 }
1072 
1073 #endif
1074