1 //===-- ProcessMonitor.cpp ------------------------------------ -*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
16 #include <sys/ptrace.h>
17 #include <sys/socket.h>
18 #include <sys/types.h>
23 // Other libraries and framework includes
24 #include "lldb/Core/RegisterValue.h"
25 #include "lldb/Core/Scalar.h"
26 #include "lldb/Host/Host.h"
27 #include "lldb/Host/PseudoTerminal.h"
28 #include "lldb/Host/ThreadLauncher.h"
29 #include "lldb/Target/RegisterContext.h"
30 #include "lldb/Target/Thread.h"
31 #include "lldb/Target/UnixSignals.h"
32 #include "lldb/Utility/Status.h"
33 #include "llvm/Support/Errno.h"
35 #include "FreeBSDThread.h"
36 #include "Plugins/Process/POSIX/CrashReason.h"
37 #include "Plugins/Process/POSIX/ProcessPOSIXLog.h"
38 #include "ProcessFreeBSD.h"
39 #include "ProcessMonitor.h"
42 using namespace lldb_private;
44 // We disable the tracing of ptrace calls for integration builds to avoid the
45 // additional indirection and checks.
46 #ifndef LLDB_CONFIGURATION_BUILDANDINTEGRATION
47 // Wrapper for ptrace to catch errors and log calls.
49 const char *Get_PT_IO_OP(int op) {
64 // Wrapper for ptrace to catch errors and log calls. Note that ptrace sets
65 // errno on error because -1 is reserved as a valid result.
66 extern long PtraceWrapper(int req, lldb::pid_t pid, void *addr, int data,
67 const char *reqName, const char *file, int line) {
70 Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PTRACE));
73 log->Printf("ptrace(%s, %" PRIu64 ", %p, %x) called from file %s line %d",
74 reqName, pid, addr, data, file, line);
76 struct ptrace_io_desc *pi = (struct ptrace_io_desc *)addr;
78 log->Printf("PT_IO: op=%s offs=%zx size=%zu", Get_PT_IO_OP(pi->piod_op),
79 (size_t)pi->piod_offs, pi->piod_len);
83 // PtraceDisplayBytes(req, data);
86 result = ptrace(req, pid, (caddr_t)addr, data);
88 // PtraceDisplayBytes(req, data);
90 if (log && errno != 0) {
108 log->Printf("ptrace() failed; errno=%d (%s)", errno, str);
113 if (req == PT_GETREGS) {
114 struct reg *r = (struct reg *)addr;
116 log->Printf("PT_GETREGS: rip=0x%lx rsp=0x%lx rbp=0x%lx rax=0x%lx",
117 r->r_rip, r->r_rsp, r->r_rbp, r->r_rax);
119 if (req == PT_GETDBREGS || req == PT_SETDBREGS) {
120 struct dbreg *r = (struct dbreg *)addr;
121 char setget = (req == PT_GETDBREGS) ? 'G' : 'S';
123 for (int i = 0; i <= 7; i++)
124 log->Printf("PT_%cETDBREGS: dr[%d]=0x%lx", setget, i, r->dr[i]);
132 // Wrapper for ptrace when logging is not required. Sets errno to 0 prior to
134 extern long PtraceWrapper(int req, lldb::pid_t pid, void *addr, int data) {
137 result = ptrace(req, pid, (caddr_t)addr, data);
141 #define PTRACE(req, pid, addr, data) \
142 PtraceWrapper((req), (pid), (addr), (data), #req, __FILE__, __LINE__)
144 PtraceWrapper((req), (pid), (addr), (data))
147 //------------------------------------------------------------------------------
148 // Static implementations of ProcessMonitor::ReadMemory and
149 // ProcessMonitor::WriteMemory. This enables mutual recursion between these
150 // functions without needed to go thru the thread funnel.
152 static size_t DoReadMemory(lldb::pid_t pid, lldb::addr_t vm_addr, void *buf,
153 size_t size, Status &error) {
154 struct ptrace_io_desc pi_desc;
156 pi_desc.piod_op = PIOD_READ_D;
157 pi_desc.piod_offs = (void *)vm_addr;
158 pi_desc.piod_addr = buf;
159 pi_desc.piod_len = size;
161 if (PTRACE(PT_IO, pid, (caddr_t)&pi_desc, 0) < 0) {
162 error.SetErrorToErrno();
165 return pi_desc.piod_len;
168 static size_t DoWriteMemory(lldb::pid_t pid, lldb::addr_t vm_addr,
169 const void *buf, size_t size, Status &error) {
170 struct ptrace_io_desc pi_desc;
172 pi_desc.piod_op = PIOD_WRITE_D;
173 pi_desc.piod_offs = (void *)vm_addr;
174 pi_desc.piod_addr = (void *)buf;
175 pi_desc.piod_len = size;
177 if (PTRACE(PT_IO, pid, (caddr_t)&pi_desc, 0) < 0) {
178 error.SetErrorToErrno();
181 return pi_desc.piod_len;
184 // Simple helper function to ensure flags are enabled on the given file
186 static bool EnsureFDFlags(int fd, int flags, Status &error) {
189 if ((status = fcntl(fd, F_GETFL)) == -1) {
190 error.SetErrorToErrno();
194 if (fcntl(fd, F_SETFL, status | flags) == -1) {
195 error.SetErrorToErrno();
202 //------------------------------------------------------------------------------
204 /// Represents a ProcessMonitor operation.
206 /// Under FreeBSD, it is not possible to ptrace() from any other thread but
207 /// the one that spawned or attached to the process from the start.
208 /// Therefore, when a ProcessMonitor is asked to deliver or change the state
209 /// of an inferior process the operation must be "funneled" to a specific
210 /// thread to perform the task. The Operation class provides an abstract base
211 /// for all services the ProcessMonitor must perform via the single virtual
212 /// function Execute, thus encapsulating the code that needs to run in the
213 /// privileged context.
216 virtual ~Operation() {}
217 virtual void Execute(ProcessMonitor *monitor) = 0;
220 //------------------------------------------------------------------------------
221 /// @class ReadOperation
222 /// Implements ProcessMonitor::ReadMemory.
223 class ReadOperation : public Operation {
225 ReadOperation(lldb::addr_t addr, void *buff, size_t size, Status &error,
227 : m_addr(addr), m_buff(buff), m_size(size), m_error(error),
230 void Execute(ProcessMonitor *monitor);
240 void ReadOperation::Execute(ProcessMonitor *monitor) {
241 lldb::pid_t pid = monitor->GetPID();
243 m_result = DoReadMemory(pid, m_addr, m_buff, m_size, m_error);
246 //------------------------------------------------------------------------------
247 /// @class WriteOperation
248 /// Implements ProcessMonitor::WriteMemory.
249 class WriteOperation : public Operation {
251 WriteOperation(lldb::addr_t addr, const void *buff, size_t size,
252 Status &error, size_t &result)
253 : m_addr(addr), m_buff(buff), m_size(size), m_error(error),
256 void Execute(ProcessMonitor *monitor);
266 void WriteOperation::Execute(ProcessMonitor *monitor) {
267 lldb::pid_t pid = monitor->GetPID();
269 m_result = DoWriteMemory(pid, m_addr, m_buff, m_size, m_error);
272 //------------------------------------------------------------------------------
273 /// @class ReadRegOperation
274 /// Implements ProcessMonitor::ReadRegisterValue.
275 class ReadRegOperation : public Operation {
277 ReadRegOperation(lldb::tid_t tid, unsigned offset, unsigned size,
278 RegisterValue &value, bool &result)
279 : m_tid(tid), m_offset(offset), m_size(size), m_value(value),
282 void Execute(ProcessMonitor *monitor);
288 RegisterValue &m_value;
292 void ReadRegOperation::Execute(ProcessMonitor *monitor) {
296 if ((rc = PTRACE(PT_GETREGS, m_tid, (caddr_t)®s, 0)) < 0) {
299 // 'struct reg' contains only 32- or 64-bit register values. Punt on
300 // others. Also, not all entries may be uintptr_t sized, such as 32-bit
301 // processes on powerpc64 (probably the same for i386 on amd64)
302 if (m_size == sizeof(uint32_t))
303 m_value = *(uint32_t *)(((caddr_t)®s) + m_offset);
304 else if (m_size == sizeof(uint64_t))
305 m_value = *(uint64_t *)(((caddr_t)®s) + m_offset);
307 memcpy((void *)&m_value, (((caddr_t)®s) + m_offset), m_size);
312 //------------------------------------------------------------------------------
313 /// @class WriteRegOperation
314 /// Implements ProcessMonitor::WriteRegisterValue.
315 class WriteRegOperation : public Operation {
317 WriteRegOperation(lldb::tid_t tid, unsigned offset,
318 const RegisterValue &value, bool &result)
319 : m_tid(tid), m_offset(offset), m_value(value), m_result(result) {}
321 void Execute(ProcessMonitor *monitor);
326 const RegisterValue &m_value;
330 void WriteRegOperation::Execute(ProcessMonitor *monitor) {
333 if (PTRACE(PT_GETREGS, m_tid, (caddr_t)®s, 0) < 0) {
337 *(uintptr_t *)(((caddr_t)®s) + m_offset) =
338 (uintptr_t)m_value.GetAsUInt64();
339 if (PTRACE(PT_SETREGS, m_tid, (caddr_t)®s, 0) < 0)
345 //------------------------------------------------------------------------------
346 /// @class ReadDebugRegOperation
347 /// Implements ProcessMonitor::ReadDebugRegisterValue.
348 class ReadDebugRegOperation : public Operation {
350 ReadDebugRegOperation(lldb::tid_t tid, unsigned offset, unsigned size,
351 RegisterValue &value, bool &result)
352 : m_tid(tid), m_offset(offset), m_size(size), m_value(value),
355 void Execute(ProcessMonitor *monitor);
361 RegisterValue &m_value;
365 void ReadDebugRegOperation::Execute(ProcessMonitor *monitor) {
369 if ((rc = PTRACE(PT_GETDBREGS, m_tid, (caddr_t)®s, 0)) < 0) {
372 if (m_size == sizeof(uintptr_t))
373 m_value = *(uintptr_t *)(((caddr_t)®s) + m_offset);
375 memcpy((void *)&m_value, (((caddr_t)®s) + m_offset), m_size);
380 //------------------------------------------------------------------------------
381 /// @class WriteDebugRegOperation
382 /// Implements ProcessMonitor::WriteDebugRegisterValue.
383 class WriteDebugRegOperation : public Operation {
385 WriteDebugRegOperation(lldb::tid_t tid, unsigned offset,
386 const RegisterValue &value, bool &result)
387 : m_tid(tid), m_offset(offset), m_value(value), m_result(result) {}
389 void Execute(ProcessMonitor *monitor);
394 const RegisterValue &m_value;
398 void WriteDebugRegOperation::Execute(ProcessMonitor *monitor) {
401 if (PTRACE(PT_GETDBREGS, m_tid, (caddr_t)®s, 0) < 0) {
405 *(uintptr_t *)(((caddr_t)®s) + m_offset) =
406 (uintptr_t)m_value.GetAsUInt64();
407 if (PTRACE(PT_SETDBREGS, m_tid, (caddr_t)®s, 0) < 0)
413 //------------------------------------------------------------------------------
414 /// @class ReadGPROperation
415 /// Implements ProcessMonitor::ReadGPR.
416 class ReadGPROperation : public Operation {
418 ReadGPROperation(lldb::tid_t tid, void *buf, bool &result)
419 : m_tid(tid), m_buf(buf), m_result(result) {}
421 void Execute(ProcessMonitor *monitor);
429 void ReadGPROperation::Execute(ProcessMonitor *monitor) {
433 rc = PTRACE(PT_GETREGS, m_tid, (caddr_t)m_buf, 0);
440 //------------------------------------------------------------------------------
441 /// @class ReadFPROperation
442 /// Implements ProcessMonitor::ReadFPR.
443 class ReadFPROperation : public Operation {
445 ReadFPROperation(lldb::tid_t tid, void *buf, bool &result)
446 : m_tid(tid), m_buf(buf), m_result(result) {}
448 void Execute(ProcessMonitor *monitor);
456 void ReadFPROperation::Execute(ProcessMonitor *monitor) {
457 if (PTRACE(PT_GETFPREGS, m_tid, (caddr_t)m_buf, 0) < 0)
463 //------------------------------------------------------------------------------
464 /// @class WriteGPROperation
465 /// Implements ProcessMonitor::WriteGPR.
466 class WriteGPROperation : public Operation {
468 WriteGPROperation(lldb::tid_t tid, void *buf, bool &result)
469 : m_tid(tid), m_buf(buf), m_result(result) {}
471 void Execute(ProcessMonitor *monitor);
479 void WriteGPROperation::Execute(ProcessMonitor *monitor) {
480 if (PTRACE(PT_SETREGS, m_tid, (caddr_t)m_buf, 0) < 0)
486 //------------------------------------------------------------------------------
487 /// @class WriteFPROperation
488 /// Implements ProcessMonitor::WriteFPR.
489 class WriteFPROperation : public Operation {
491 WriteFPROperation(lldb::tid_t tid, void *buf, bool &result)
492 : m_tid(tid), m_buf(buf), m_result(result) {}
494 void Execute(ProcessMonitor *monitor);
502 void WriteFPROperation::Execute(ProcessMonitor *monitor) {
503 if (PTRACE(PT_SETFPREGS, m_tid, (caddr_t)m_buf, 0) < 0)
509 //------------------------------------------------------------------------------
510 /// @class ResumeOperation
511 /// Implements ProcessMonitor::Resume.
512 class ResumeOperation : public Operation {
514 ResumeOperation(uint32_t signo, bool &result)
515 : m_signo(signo), m_result(result) {}
517 void Execute(ProcessMonitor *monitor);
524 void ResumeOperation::Execute(ProcessMonitor *monitor) {
525 lldb::pid_t pid = monitor->GetPID();
528 if (m_signo != LLDB_INVALID_SIGNAL_NUMBER)
531 if (PTRACE(PT_CONTINUE, pid, (caddr_t)1, data)) {
532 Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS));
533 LLDB_LOG(log, "ResumeOperation ({0}) failed: {1}", pid,
534 llvm::sys::StrError(errno));
540 //------------------------------------------------------------------------------
541 /// @class SingleStepOperation
542 /// Implements ProcessMonitor::SingleStep.
543 class SingleStepOperation : public Operation {
545 SingleStepOperation(uint32_t signo, bool &result)
546 : m_signo(signo), m_result(result) {}
548 void Execute(ProcessMonitor *monitor);
555 void SingleStepOperation::Execute(ProcessMonitor *monitor) {
556 lldb::pid_t pid = monitor->GetPID();
559 if (m_signo != LLDB_INVALID_SIGNAL_NUMBER)
562 if (PTRACE(PT_STEP, pid, NULL, data))
568 //------------------------------------------------------------------------------
569 /// @class LwpInfoOperation
570 /// Implements ProcessMonitor::GetLwpInfo.
571 class LwpInfoOperation : public Operation {
573 LwpInfoOperation(lldb::tid_t tid, void *info, bool &result, int &ptrace_err)
574 : m_tid(tid), m_info(info), m_result(result), m_err(ptrace_err) {}
576 void Execute(ProcessMonitor *monitor);
585 void LwpInfoOperation::Execute(ProcessMonitor *monitor) {
586 struct ptrace_lwpinfo plwp;
588 if (PTRACE(PT_LWPINFO, m_tid, (caddr_t)&plwp, sizeof(plwp))) {
592 memcpy(m_info, &plwp, sizeof(plwp));
597 //------------------------------------------------------------------------------
598 /// @class ThreadSuspendOperation
599 /// Implements ProcessMonitor::ThreadSuspend.
600 class ThreadSuspendOperation : public Operation {
602 ThreadSuspendOperation(lldb::tid_t tid, bool suspend, bool &result)
603 : m_tid(tid), m_suspend(suspend), m_result(result) {}
605 void Execute(ProcessMonitor *monitor);
613 void ThreadSuspendOperation::Execute(ProcessMonitor *monitor) {
614 m_result = !PTRACE(m_suspend ? PT_SUSPEND : PT_RESUME, m_tid, NULL, 0);
617 //------------------------------------------------------------------------------
618 /// @class EventMessageOperation
619 /// Implements ProcessMonitor::GetEventMessage.
620 class EventMessageOperation : public Operation {
622 EventMessageOperation(lldb::tid_t tid, unsigned long *message, bool &result)
623 : m_tid(tid), m_message(message), m_result(result) {}
625 void Execute(ProcessMonitor *monitor);
629 unsigned long *m_message;
633 void EventMessageOperation::Execute(ProcessMonitor *monitor) {
634 struct ptrace_lwpinfo plwp;
636 if (PTRACE(PT_LWPINFO, m_tid, (caddr_t)&plwp, sizeof(plwp)))
639 if (plwp.pl_flags & PL_FLAG_FORKED) {
640 *m_message = plwp.pl_child_pid;
647 //------------------------------------------------------------------------------
648 /// @class KillOperation
649 /// Implements ProcessMonitor::Kill.
650 class KillOperation : public Operation {
652 KillOperation(bool &result) : m_result(result) {}
654 void Execute(ProcessMonitor *monitor);
660 void KillOperation::Execute(ProcessMonitor *monitor) {
661 lldb::pid_t pid = monitor->GetPID();
663 if (PTRACE(PT_KILL, pid, NULL, 0))
669 //------------------------------------------------------------------------------
670 /// @class DetachOperation
671 /// Implements ProcessMonitor::Detach.
672 class DetachOperation : public Operation {
674 DetachOperation(Status &result) : m_error(result) {}
676 void Execute(ProcessMonitor *monitor);
682 void DetachOperation::Execute(ProcessMonitor *monitor) {
683 lldb::pid_t pid = monitor->GetPID();
685 if (PTRACE(PT_DETACH, pid, NULL, 0) < 0)
686 m_error.SetErrorToErrno();
689 ProcessMonitor::OperationArgs::OperationArgs(ProcessMonitor *monitor)
690 : m_monitor(monitor) {
691 sem_init(&m_semaphore, 0, 0);
694 ProcessMonitor::OperationArgs::~OperationArgs() { sem_destroy(&m_semaphore); }
696 ProcessMonitor::LaunchArgs::LaunchArgs(ProcessMonitor *monitor,
697 lldb_private::Module *module,
698 char const **argv, Environment env,
699 const FileSpec &stdin_file_spec,
700 const FileSpec &stdout_file_spec,
701 const FileSpec &stderr_file_spec,
702 const FileSpec &working_dir)
703 : OperationArgs(monitor), m_module(module), m_argv(argv),
704 m_env(std::move(env)), m_stdin_file_spec(stdin_file_spec),
705 m_stdout_file_spec(stdout_file_spec),
706 m_stderr_file_spec(stderr_file_spec), m_working_dir(working_dir) {}
708 ProcessMonitor::LaunchArgs::~LaunchArgs() {}
710 ProcessMonitor::AttachArgs::AttachArgs(ProcessMonitor *monitor, lldb::pid_t pid)
711 : OperationArgs(monitor), m_pid(pid) {}
713 ProcessMonitor::AttachArgs::~AttachArgs() {}
715 //------------------------------------------------------------------------------
716 /// The basic design of the ProcessMonitor is built around two threads.
718 /// One thread (@see SignalThread) simply blocks on a call to waitpid()
719 /// looking for changes in the debugee state. When a change is detected a
720 /// ProcessMessage is sent to the associated ProcessFreeBSD instance. This
721 /// thread "drives" state changes in the debugger.
723 /// The second thread (@see OperationThread) is responsible for two things 1)
724 /// launching or attaching to the inferior process, and then 2) servicing
725 /// operations such as register reads/writes, stepping, etc. See the comments
726 /// on the Operation class for more info as to why this is needed.
727 ProcessMonitor::ProcessMonitor(
728 ProcessFreeBSD *process, Module *module, const char *argv[],
729 Environment env, const FileSpec &stdin_file_spec,
730 const FileSpec &stdout_file_spec, const FileSpec &stderr_file_spec,
731 const FileSpec &working_dir,
732 const lldb_private::ProcessLaunchInfo & /* launch_info */,
733 lldb_private::Status &error)
734 : m_process(static_cast<ProcessFreeBSD *>(process)),
735 m_pid(LLDB_INVALID_PROCESS_ID), m_terminal_fd(-1), m_operation(0) {
736 using namespace std::placeholders;
738 std::unique_ptr<LaunchArgs> args(
739 new LaunchArgs(this, module, argv, std::move(env), stdin_file_spec,
740 stdout_file_spec, stderr_file_spec, working_dir));
742 sem_init(&m_operation_pending, 0, 0);
743 sem_init(&m_operation_done, 0, 0);
745 StartLaunchOpThread(args.get(), error);
746 if (!error.Success())
749 if (llvm::sys::RetryAfterSignal(-1, sem_wait, &args->m_semaphore) == -1) {
750 error.SetErrorToErrno();
754 // Check that the launch was a success.
755 if (!args->m_error.Success()) {
757 error = args->m_error;
761 // Finally, start monitoring the child process for change in state.
762 m_monitor_thread = Host::StartMonitoringChildProcess(
763 std::bind(&ProcessMonitor::MonitorCallback, this, _1, _2, _3, _4),
765 if (!m_monitor_thread.IsJoinable()) {
766 error.SetErrorToGenericError();
767 error.SetErrorString("Process launch failed.");
772 ProcessMonitor::ProcessMonitor(ProcessFreeBSD *process, lldb::pid_t pid,
773 lldb_private::Status &error)
774 : m_process(static_cast<ProcessFreeBSD *>(process)), m_pid(pid),
775 m_terminal_fd(-1), m_operation(0) {
776 using namespace std::placeholders;
778 sem_init(&m_operation_pending, 0, 0);
779 sem_init(&m_operation_done, 0, 0);
781 std::unique_ptr<AttachArgs> args(new AttachArgs(this, pid));
783 StartAttachOpThread(args.get(), error);
784 if (!error.Success())
787 if (llvm::sys::RetryAfterSignal(-1, sem_wait, &args->m_semaphore) == -1) {
788 error.SetErrorToErrno();
792 // Check that the attach was a success.
793 if (!args->m_error.Success()) {
795 error = args->m_error;
799 // Finally, start monitoring the child process for change in state.
800 m_monitor_thread = Host::StartMonitoringChildProcess(
801 std::bind(&ProcessMonitor::MonitorCallback, this, _1, _2, _3, _4),
803 if (!m_monitor_thread.IsJoinable()) {
804 error.SetErrorToGenericError();
805 error.SetErrorString("Process attach failed.");
810 ProcessMonitor::~ProcessMonitor() { StopMonitor(); }
812 //------------------------------------------------------------------------------
813 // Thread setup and tear down.
814 void ProcessMonitor::StartLaunchOpThread(LaunchArgs *args, Status &error) {
815 static const char *g_thread_name = "lldb.process.freebsd.operation";
817 if (m_operation_thread.IsJoinable())
821 ThreadLauncher::LaunchThread(g_thread_name, LaunchOpThread, args, &error);
824 void *ProcessMonitor::LaunchOpThread(void *arg) {
825 LaunchArgs *args = static_cast<LaunchArgs *>(arg);
828 sem_post(&args->m_semaphore);
832 ServeOperation(args);
836 bool ProcessMonitor::Launch(LaunchArgs *args) {
837 ProcessMonitor *monitor = args->m_monitor;
838 ProcessFreeBSD &process = monitor->GetProcess();
839 const char **argv = args->m_argv;
840 const FileSpec &stdin_file_spec = args->m_stdin_file_spec;
841 const FileSpec &stdout_file_spec = args->m_stdout_file_spec;
842 const FileSpec &stderr_file_spec = args->m_stderr_file_spec;
843 const FileSpec &working_dir = args->m_working_dir;
845 PseudoTerminal terminal;
846 const size_t err_len = 1024;
847 char err_str[err_len];
850 // Propagate the environment if one is not supplied.
851 Environment::Envp envp =
852 (args->m_env.empty() ? Host::GetEnvironment() : args->m_env).getEnvp();
854 if ((pid = terminal.Fork(err_str, err_len)) == -1) {
855 args->m_error.SetErrorToGenericError();
856 args->m_error.SetErrorString("Process fork failed.");
860 // Recognized child exit status codes.
873 // Trace this process.
874 if (PTRACE(PT_TRACE_ME, 0, NULL, 0) < 0)
877 // terminal has already dupped the tty descriptors to stdin/out/err. This
878 // closes original fd from which they were copied (and avoids leaking
879 // descriptors to the debugged process.
880 terminal.CloseSlaveFileDescriptor();
882 // Do not inherit setgid powers.
883 if (setgid(getgid()) != 0)
886 // Let us have our own process group.
889 // Dup file descriptors if needed.
891 // FIXME: If two or more of the paths are the same we needlessly open
892 // the same file multiple times.
894 if (!DupDescriptor(stdin_file_spec, STDIN_FILENO, O_RDONLY))
895 exit(eDupStdinFailed);
897 if (stdout_file_spec)
898 if (!DupDescriptor(stdout_file_spec, STDOUT_FILENO, O_WRONLY | O_CREAT))
899 exit(eDupStdoutFailed);
901 if (stderr_file_spec)
902 if (!DupDescriptor(stderr_file_spec, STDERR_FILENO, O_WRONLY | O_CREAT))
903 exit(eDupStderrFailed);
905 // Change working directory
906 if (working_dir && 0 != ::chdir(working_dir.GetCString()))
909 // Execute. We should never return.
910 execve(argv[0], const_cast<char *const *>(argv), envp);
914 // Wait for the child process to to trap on its call to execve.
917 if ((wpid = waitpid(pid, &status, 0)) < 0) {
918 args->m_error.SetErrorToErrno();
920 } else if (WIFEXITED(status)) {
921 // open, dup or execve likely failed for some reason.
922 args->m_error.SetErrorToGenericError();
923 switch (WEXITSTATUS(status)) {
925 args->m_error.SetErrorString("Child ptrace failed.");
927 case eDupStdinFailed:
928 args->m_error.SetErrorString("Child open stdin failed.");
930 case eDupStdoutFailed:
931 args->m_error.SetErrorString("Child open stdout failed.");
933 case eDupStderrFailed:
934 args->m_error.SetErrorString("Child open stderr failed.");
937 args->m_error.SetErrorString("Child failed to set working directory.");
940 args->m_error.SetErrorString("Child exec failed.");
943 args->m_error.SetErrorString("Child setgid failed.");
946 args->m_error.SetErrorString("Child returned unknown exit status.");
951 assert(WIFSTOPPED(status) && wpid == (::pid_t)pid &&
952 "Could not sync with inferior process.");
955 // Have the child raise an event on exit. This is used to keep the child in
956 // limbo until it is destroyed.
957 if (PTRACE(PTRACE_SETOPTIONS, pid, NULL, PTRACE_O_TRACEEXIT) < 0) {
958 args->m_error.SetErrorToErrno();
962 // Release the master terminal descriptor and pass it off to the
963 // ProcessMonitor instance. Similarly stash the inferior pid.
964 monitor->m_terminal_fd = terminal.ReleaseMasterFileDescriptor();
965 monitor->m_pid = pid;
967 // Set the terminal fd to be in non blocking mode (it simplifies the
968 // implementation of ProcessFreeBSD::GetSTDOUT to have a non-blocking
969 // descriptor to read from).
970 if (!EnsureFDFlags(monitor->m_terminal_fd, O_NONBLOCK, args->m_error))
973 process.SendMessage(ProcessMessage::Attach(pid));
976 return args->m_error.Success();
979 void ProcessMonitor::StartAttachOpThread(AttachArgs *args,
980 lldb_private::Status &error) {
981 static const char *g_thread_name = "lldb.process.freebsd.operation";
983 if (m_operation_thread.IsJoinable())
987 ThreadLauncher::LaunchThread(g_thread_name, AttachOpThread, args, &error);
990 void *ProcessMonitor::AttachOpThread(void *arg) {
991 AttachArgs *args = static_cast<AttachArgs *>(arg);
995 ServeOperation(args);
999 void ProcessMonitor::Attach(AttachArgs *args) {
1000 lldb::pid_t pid = args->m_pid;
1002 ProcessMonitor *monitor = args->m_monitor;
1003 ProcessFreeBSD &process = monitor->GetProcess();
1006 args->m_error.SetErrorToGenericError();
1007 args->m_error.SetErrorString("Attaching to process 1 is not allowed.");
1011 // Attach to the requested process.
1012 if (PTRACE(PT_ATTACH, pid, NULL, 0) < 0) {
1013 args->m_error.SetErrorToErrno();
1018 if ((status = waitpid(pid, NULL, 0)) < 0) {
1019 args->m_error.SetErrorToErrno();
1023 process.SendMessage(ProcessMessage::Attach(pid));
1027 ProcessMonitor::GetCurrentThreadIDs(std::vector<lldb::tid_t> &thread_ids) {
1033 tdcnt = PTRACE(PT_GETNUMLWPS, m_pid, NULL, 0);
1036 tids = (lwpid_t *)malloc(tdcnt * sizeof(*tids));
1039 if (PTRACE(PT_GETLWPLIST, m_pid, (void *)tids, tdcnt) < 0) {
1043 thread_ids = std::vector<lldb::tid_t>(tids, tids + tdcnt);
1045 return thread_ids.size();
1048 bool ProcessMonitor::MonitorCallback(ProcessMonitor *monitor, lldb::pid_t pid,
1049 bool exited, int signal, int status) {
1050 ProcessMessage message;
1051 ProcessFreeBSD *process = monitor->m_process;
1053 bool stop_monitoring;
1054 struct ptrace_lwpinfo plwp;
1057 Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS));
1061 log->Printf("ProcessMonitor::%s() got exit signal, tid = %" PRIu64,
1063 message = ProcessMessage::Exit(pid, status);
1064 process->SendMessage(message);
1065 return pid == process->GetID();
1068 if (!monitor->GetLwpInfo(pid, &plwp, ptrace_err))
1069 stop_monitoring = true; // pid is gone. Bail.
1071 switch (plwp.pl_siginfo.si_signo) {
1073 message = MonitorSIGTRAP(monitor, &plwp.pl_siginfo, plwp.pl_lwpid);
1077 message = MonitorSignal(monitor, &plwp.pl_siginfo, plwp.pl_lwpid);
1081 process->SendMessage(message);
1082 stop_monitoring = message.GetKind() == ProcessMessage::eExitMessage;
1085 return stop_monitoring;
1088 ProcessMessage ProcessMonitor::MonitorSIGTRAP(ProcessMonitor *monitor,
1089 const siginfo_t *info,
1091 ProcessMessage message;
1093 Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS));
1096 assert(info && info->si_signo == SIGTRAP && "Unexpected child signal!");
1098 switch (info->si_code) {
1100 assert(false && "Unexpected SIGTRAP code!");
1103 case (SIGTRAP /* | (PTRACE_EVENT_EXIT << 8) */): {
1104 // The inferior process is about to exit. Maintain the process in a state
1105 // of "limbo" until we are explicitly commanded to detach, destroy, resume,
1107 unsigned long data = 0;
1108 if (!monitor->GetEventMessage(tid, &data))
1111 log->Printf("ProcessMonitor::%s() received exit? event, data = %lx, tid "
1113 __FUNCTION__, data, tid);
1114 message = ProcessMessage::Limbo(tid, (data >> 8));
1121 // Map TRAP_CAP to a trace trap in the absense of a more specific handler.
1125 log->Printf("ProcessMonitor::%s() received trace event, tid = %" PRIu64
1127 __FUNCTION__, tid, info->si_code);
1128 message = ProcessMessage::Trace(tid);
1133 if (monitor->m_process->IsSoftwareStepBreakpoint(tid)) {
1135 log->Printf("ProcessMonitor::%s() received sw single step breakpoint "
1136 "event, tid = %" PRIu64,
1138 message = ProcessMessage::Trace(tid);
1142 "ProcessMonitor::%s() received breakpoint event, tid = %" PRIu64,
1144 message = ProcessMessage::Break(tid);
1152 ProcessMessage ProcessMonitor::MonitorSignal(ProcessMonitor *monitor,
1153 const siginfo_t *info,
1155 ProcessMessage message;
1156 int signo = info->si_signo;
1158 Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS));
1160 // POSIX says that process behaviour is undefined after it ignores a SIGFPE,
1161 // SIGILL, SIGSEGV, or SIGBUS *unless* that signal was generated by a kill(2)
1162 // or raise(3). Similarly for tgkill(2) on FreeBSD.
1164 // IOW, user generated signals never generate what we consider to be a
1167 // Similarly, ACK signals generated by this monitor.
1168 if (info->si_code == SI_USER) {
1171 "ProcessMonitor::%s() received signal %s with code %s, pid = %d",
1173 monitor->m_process->GetUnixSignals()->GetSignalAsCString(signo),
1174 "SI_USER", info->si_pid);
1175 if (info->si_pid == getpid())
1176 return ProcessMessage::SignalDelivered(tid, signo);
1178 return ProcessMessage::Signal(tid, signo);
1183 "ProcessMonitor::%s() received signal %s", __FUNCTION__,
1184 monitor->m_process->GetUnixSignals()->GetSignalAsCString(signo));
1191 lldb::addr_t fault_addr = reinterpret_cast<lldb::addr_t>(info->si_addr);
1192 const auto reason = GetCrashReason(*info);
1193 if (reason != CrashReason::eInvalidCrashReason) {
1194 return ProcessMessage::Crash(tid, reason, signo, fault_addr);
1195 } // else; Use atleast si_signo info for other si_code
1198 // Everything else is "normal" and does not require any special action on our
1200 return ProcessMessage::Signal(tid, signo);
1203 void ProcessMonitor::ServeOperation(OperationArgs *args) {
1204 ProcessMonitor *monitor = args->m_monitor;
1206 // We are finised with the arguments and are ready to go. Sync with the
1207 // parent thread and start serving operations on the inferior.
1208 sem_post(&args->m_semaphore);
1211 // wait for next pending operation
1212 sem_wait(&monitor->m_operation_pending);
1214 monitor->m_operation->Execute(monitor);
1216 // notify calling thread that operation is complete
1217 sem_post(&monitor->m_operation_done);
1221 void ProcessMonitor::DoOperation(Operation *op) {
1222 std::lock_guard<std::mutex> guard(m_operation_mutex);
1226 // notify operation thread that an operation is ready to be processed
1227 sem_post(&m_operation_pending);
1229 // wait for operation to complete
1230 sem_wait(&m_operation_done);
1233 size_t ProcessMonitor::ReadMemory(lldb::addr_t vm_addr, void *buf, size_t size,
1236 ReadOperation op(vm_addr, buf, size, error, result);
1241 size_t ProcessMonitor::WriteMemory(lldb::addr_t vm_addr, const void *buf,
1242 size_t size, lldb_private::Status &error) {
1244 WriteOperation op(vm_addr, buf, size, error, result);
1249 bool ProcessMonitor::ReadRegisterValue(lldb::tid_t tid, unsigned offset,
1250 const char *reg_name, unsigned size,
1251 RegisterValue &value) {
1253 ReadRegOperation op(tid, offset, size, value, result);
1258 bool ProcessMonitor::WriteRegisterValue(lldb::tid_t tid, unsigned offset,
1259 const char *reg_name,
1260 const RegisterValue &value) {
1262 WriteRegOperation op(tid, offset, value, result);
1267 bool ProcessMonitor::ReadDebugRegisterValue(
1268 lldb::tid_t tid, unsigned offset, const char *reg_name, unsigned size,
1269 lldb_private::RegisterValue &value) {
1271 ReadDebugRegOperation op(tid, offset, size, value, result);
1276 bool ProcessMonitor::WriteDebugRegisterValue(
1277 lldb::tid_t tid, unsigned offset, const char *reg_name,
1278 const lldb_private::RegisterValue &value) {
1280 WriteDebugRegOperation op(tid, offset, value, result);
1285 bool ProcessMonitor::ReadGPR(lldb::tid_t tid, void *buf, size_t buf_size) {
1287 ReadGPROperation op(tid, buf, result);
1292 bool ProcessMonitor::ReadFPR(lldb::tid_t tid, void *buf, size_t buf_size) {
1294 ReadFPROperation op(tid, buf, result);
1299 bool ProcessMonitor::ReadRegisterSet(lldb::tid_t tid, void *buf,
1300 size_t buf_size, unsigned int regset) {
1304 bool ProcessMonitor::WriteGPR(lldb::tid_t tid, void *buf, size_t buf_size) {
1306 WriteGPROperation op(tid, buf, result);
1311 bool ProcessMonitor::WriteFPR(lldb::tid_t tid, void *buf, size_t buf_size) {
1313 WriteFPROperation op(tid, buf, result);
1318 bool ProcessMonitor::WriteRegisterSet(lldb::tid_t tid, void *buf,
1319 size_t buf_size, unsigned int regset) {
1323 bool ProcessMonitor::ReadThreadPointer(lldb::tid_t tid, lldb::addr_t &value) {
1327 bool ProcessMonitor::Resume(lldb::tid_t unused, uint32_t signo) {
1329 Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS));
1332 const char *signame =
1333 m_process->GetUnixSignals()->GetSignalAsCString(signo);
1334 if (signame == nullptr)
1336 log->Printf("ProcessMonitor::%s() resuming pid %" PRIu64 " with signal %s",
1337 __FUNCTION__, GetPID(), signame);
1339 ResumeOperation op(signo, result);
1342 log->Printf("ProcessMonitor::%s() resuming result = %s", __FUNCTION__,
1343 result ? "true" : "false");
1347 bool ProcessMonitor::SingleStep(lldb::tid_t unused, uint32_t signo) {
1349 SingleStepOperation op(signo, result);
1354 bool ProcessMonitor::Kill() {
1356 KillOperation op(result);
1361 bool ProcessMonitor::GetLwpInfo(lldb::tid_t tid, void *lwpinfo,
1364 LwpInfoOperation op(tid, lwpinfo, result, ptrace_err);
1369 bool ProcessMonitor::ThreadSuspend(lldb::tid_t tid, bool suspend) {
1371 ThreadSuspendOperation op(tid, suspend, result);
1376 bool ProcessMonitor::GetEventMessage(lldb::tid_t tid, unsigned long *message) {
1378 EventMessageOperation op(tid, message, result);
1383 lldb_private::Status ProcessMonitor::Detach(lldb::tid_t tid) {
1384 lldb_private::Status error;
1385 if (tid != LLDB_INVALID_THREAD_ID) {
1386 DetachOperation op(error);
1392 bool ProcessMonitor::DupDescriptor(const FileSpec &file_spec, int fd,
1394 int target_fd = open(file_spec.GetCString(), flags, 0666);
1396 if (target_fd == -1)
1399 if (dup2(target_fd, fd) == -1)
1402 return (close(target_fd) == -1) ? false : true;
1405 void ProcessMonitor::StopMonitoringChildProcess() {
1406 if (m_monitor_thread.IsJoinable()) {
1407 m_monitor_thread.Cancel();
1408 m_monitor_thread.Join(nullptr);
1409 m_monitor_thread.Reset();
1413 void ProcessMonitor::StopMonitor() {
1414 StopMonitoringChildProcess();
1416 sem_destroy(&m_operation_pending);
1417 sem_destroy(&m_operation_done);
1418 if (m_terminal_fd >= 0) {
1419 close(m_terminal_fd);
1424 // FIXME: On Linux, when a new thread is created, we receive to notifications,
1425 // (1) a SIGTRAP|PTRACE_EVENT_CLONE from the main process thread with the child
1426 // thread id as additional information, and (2) a SIGSTOP|SI_USER from the new
1427 // child thread indicating that it has is stopped because we attached. We have
1428 // no guarantee of the order in which these arrive, but we need both before we
1429 // are ready to proceed. We currently keep a list of threads which have sent
1430 // the initial SIGSTOP|SI_USER event. Then when we receive the
1431 // SIGTRAP|PTRACE_EVENT_CLONE notification, if the initial stop has not
1432 // occurred we call ProcessMonitor::WaitForInitialTIDStop() to wait for it.
1434 // Right now, the above logic is in ProcessPOSIX, so we need a definition of
1435 // this function in the FreeBSD ProcessMonitor implementation even if it isn't
1436 // logically needed.
1438 // We really should figure out what actually happens on FreeBSD and move the
1439 // Linux-specific logic out of ProcessPOSIX as needed.
1441 bool ProcessMonitor::WaitForInitialTIDStop(lldb::tid_t tid) { return true; }
1443 void ProcessMonitor::StopOpThread() {
1444 if (!m_operation_thread.IsJoinable())
1447 m_operation_thread.Cancel();
1448 m_operation_thread.Join(nullptr);
1449 m_operation_thread.Reset();