rstudio/src/cpp/core/system/PosixChildProcess.cpp at main · ssh352/rstudio · GitHub

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* PosixChildProcess.cpp

* Unless you have received this program directly from Posit Software pursuant

* to the terms of a commercial license agreement with Posit Software, then

* this program is licensed to you under the terms of version 3 of the

* GNU Affero General Public License. This program is distributed WITHOUT

* ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING THOSE OF NON-INFRINGEMENT,

* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Please refer to the

* AGPL (http://www.gnu.org/licenses/agpl-3.0.txt) for more details.

#include "ChildProcessSubprocPoll.hpp"

#include <atomic>

#include <fcntl.h>

#include <signal.h>

#include <unistd.h>

#ifdef __APPLE__

#include <util.h>

#include <sys/ttycom.h>

#include <sys/ioctl.h>

#elif defined(__linux__)

#include <pty.h>

#include <asm/ioctls.h>

#include <sys/prctl.h>

#endif

#include <sys/wait.h>

#include <sys/types.h>

#include <boost/asio.hpp>

#include <boost/bind/bind.hpp>

#include <shared_core/Error.hpp>

#include <core/Log.hpp>

#include <core/PerformanceTimer.hpp>

#include <core/Thread.hpp>

#include <core/system/PosixChildProcess.hpp>

#include <core/system/PosixSystem.hpp>

#include <core/system/PosixUser.hpp>

#include <core/system/ProcessArgs.hpp>

#include <core/system/ShellUtils.hpp>

using namespace boost::placeholders;

namespace rstudio {

namespace core {

namespace system {

namespace {

// pipe handle indexes

const int READ = 0;

const int WRITE = 1;

const std::size_t READ_ERR = -1;

// how long we keep "saw activity" state at true even if we haven't seen

// new activity

const boost::posix_time::milliseconds kResetRecentDelay =

boost::posix_time::milliseconds(1000);

// how often we update "has subprocesses" flag

const boost::posix_time::milliseconds kCheckSubprocDelay =

boost::posix_time::milliseconds(200);

// how often we query and store current working directory of subprocess

const boost::posix_time::milliseconds kCheckCwdDelay =

boost::posix_time::milliseconds(2000);

int resolveExitStatus(int status)

{

if (WIFEXITED(status))

{

return WEXITSTATUS(status);

}

else if (WIFSIGNALED(status))

{

// return bash-style exit codes for process terminated by a signal

// ex: if killed with SIGTERM, returns 128 + 15 = 143

return 128 + WTERMSIG(status);

}

else

return status;

}

void setPipeNonBlocking(int pipeFd)

{

int flags = ::fcntl(pipeFd, F_GETFL);

if ( (flags != -1) && !(flags & O_NONBLOCK) )

::fcntl(pipeFd, F_SETFL, flags | O_NONBLOCK);

}

void closePipe(int pipeFd, const ErrorLocation& location)

{

safePosixCall<int>(boost::bind(::close, pipeFd), location);

}

void closePipe(int* pipeDescriptors, const ErrorLocation& location)

{

closePipe(pipeDescriptors[READ], location);

closePipe(pipeDescriptors[WRITE], location);

}

Error readPipe(int pipeFd, std::string* pOutput, bool *pEOF = nullptr)

{

// default to not eof

if (pEOF)

*pEOF = false;

// setup and read into buffer

const std::size_t kBufferSize = 512;

char buffer[kBufferSize];

std::size_t bytesRead = posix::posixCall<std::size_t>(

boost::bind(::read, pipeFd, buffer, kBufferSize));

while (true)

{

// check for error

if (bytesRead == READ_ERR)

{

if (errno == EAGAIN) // carve-out for O_NONBLOCK pipes

return Success();

// on linux slave terminals return EIO rather than bytesRead == 0

// to indicate end of file

else if ((errno == EIO) && ::isatty(pipeFd))

{

if (pEOF)

*pEOF = true;

return Success();

}

else

return systemError(errno, ERROR_LOCATION);

}

// check for eof

else if (bytesRead == 0)

{

if (pEOF)

*pEOF = true;

return Success();

}

// append to output

pOutput->append(buffer, bytesRead);

// read more bytes

bytesRead = posix::posixCall<std::size_t>(

boost::bind(::read, pipeFd, buffer, kBufferSize));

}

// keep compiler happy

return Success();

}

} // anonymous namespace

struct ChildProcess::Impl

{

Impl() :

pid(-1),

fdStdin(-1),

fdStdout(-1),

fdStderr(-1),

fdMaster(-1),

ctrlC(0x03)

{

}

PidType pid;

int fdStdin;

int fdStdout;

int fdStderr;

// pty related

int fdMaster;

char ctrlC;

void init(PidType pid, int fdStdin, int fdStdout, int fdStderr)

{

this->pid = pid;

this->fdStdin = fdStdin;

this->fdStdout = fdStdout;

this->fdStderr = fdStderr;

this->fdMaster = -1;

}

void init(PidType pid, int fdMaster)

{

this->pid = pid;

this->fdStdin = fdMaster;

this->fdStdout = fdMaster;

this->fdStderr = -1;

this->fdMaster = fdMaster;

}

void closeAll(const ErrorLocation &location)

{

closeAll(true, location);

}

void closeAll(bool clearPid, const ErrorLocation& location)

{

if (clearPid)

pid = -1;

if (fdMaster != -1)

{

closeFD(&fdMaster, location);

fdStdin = -1;

fdStdout = -1;

}

else

{

closeFD(&fdStdin, location);

closeFD(&fdStdout, location);

closeFD(&fdStderr, location);

}

void closeFD(int* pFD, const ErrorLocation& location)

{

if (*pFD >= 0)

{

closePipe(*pFD, location);

*pFD = -1;

}

};

ChildProcess::ChildProcess()

: pImpl_(new Impl())

{

}

void ChildProcess::init(const std::string& exe,

const std::vector<std::string>& args,

const ProcessOptions& options)

{

exe_ = exe;

args_ = args;

options_ = options;

}

void ChildProcess::init(const std::string& command,

const ProcessOptions& options)

{

std::vector<std::string> args;

args.push_back("-c");

std::string realCommand = command;

if (!options.stdOutFile.isEmpty())

realCommand += " > " + shell_utils::escape(options.stdOutFile);

if (!options.stdErrFile.isEmpty())

realCommand += " 2> " + shell_utils::escape(options.stdErrFile);

args.push_back(realCommand);

init("/bin/sh", args, options);

}

// Initialize for an interactive terminal

void ChildProcess::init(const ProcessOptions& options)

{

if (!options.stdOutFile.isEmpty() || !options.stdErrFile.isEmpty())

{

LOG_ERROR_MESSAGE(

"stdOutFile/stdErrFile options cannot be used with interactive terminal");

}

options_ = options;

exe_ = options_.shellPath.getAbsolutePath();

args_ = options_.args;

}

ChildProcess::~ChildProcess()

{

}

Error ChildProcess::writeToStdin(const std::string& input, bool eof)

{

std::size_t written;

Error error = posix::posixCall<std::size_t>(

boost::bind(

::write,

pImpl_->fdStdin,

input.c_str(),

input.length()),

ERROR_LOCATION,

&written);

if (error)

return error;

// close if requested

if (eof)

pImpl_->closeFD(&pImpl_->fdStdin, ERROR_LOCATION);

// check for correct bytes written

if (written != static_cast<std::size_t>(input.length()))

return systemError(boost::system::errc::io_error, ERROR_LOCATION);

// return success

return Success();

}

Error ChildProcess::ptySetSize(int cols, int rows)

{

// verify we are dealing with a pseudoterminal

if (!options().pseudoterminal)

return systemError(boost::system::errc::not_supported, ERROR_LOCATION);

// define winsize structure

struct winsize winp;

winp.ws_col = cols;

winp.ws_row = rows;

winp.ws_xpixel = 0;

winp.ws_ypixel = 0;

// set it

int res = ::ioctl(pImpl_->fdMaster, TIOCSWINSZ, &winp);

if (res == -1)

return systemError(errno, ERROR_LOCATION);

else

return Success();

}

Error ChildProcess::ptyInterrupt()

{

// verify we are dealing with a pseudoterminal

if (!options().pseudoterminal)

return systemError(boost::system::errc::not_supported, ERROR_LOCATION);

// write control-c to the slave

return posix::posixCall<int>(

boost::bind(

::write,

pImpl_->fdMaster,

&pImpl_->ctrlC,

sizeof(pImpl_->ctrlC)),

ERROR_LOCATION);

}

PidType ChildProcess::getPid()

{

return pImpl_->pid;

}

Error ChildProcess::terminate()

{

// only send signal if the process is open

if (pImpl_->pid == -1)

return systemError(ESRCH, ERROR_LOCATION);

// special code path for pseudoterminal

if (options_.pseudoterminal)

{

#ifndef __APPLE__

// On Linux only do this if dealing with a Terminal-pane process.

// This is to reduce scope of this change for 1.1

// TODO: review post 1.1

if (options().smartTerminal)

{

#endif

// you need to close all of the terminal handles to get

// bash to quit, however some other processes (like svn+ssh

// require the signal)

pImpl_->closeAll(false, ERROR_LOCATION);

#ifndef __APPLE__

}

#endif

if (::killpg(::getpgid(pImpl_->pid), SIGTERM) == -1)

{

if (errno == EPERM) // see note below on carve out for EPERM

return Success();

else

return systemError(errno, ERROR_LOCATION);

}

else

return Success();

}

else

{

// determine target pid (kill just this pid or pid + children)

PidType pid = pImpl_->pid;

if (options_.detachSession || options_.terminateChildren)

{

pid = -pid;

}

// send signal

if (::kill(pid, SIGTERM) == -1)

{

// when killing an entire process group EPERM can be returned if even

// a single one of the subprocesses couldn't be killed. in this case

// the signal is still delivered and other subprocesses may have been

// killed so we don't log an error

if (pid < 0 && errno == EPERM)

return Success();

else if (errno == ESRCH)

return Success();

else

return systemError(errno, ERROR_LOCATION);

}

else

return Success();

}

bool ChildProcess::hasNonIgnoredSubprocess() const

{

// base class doesn't support subprocess-checking; override to implement

return true;

}

bool ChildProcess::hasIgnoredSubprocess() const

{

// base class doesn't support subprocess-checking; override to implement

return false;

}

core::FilePath ChildProcess::getCwd() const

{

// base class doesn't support cwd-tracking; override to implement

return FilePath();

}

bool ChildProcess::hasRecentOutput() const

{

// base class doesn't support output tracking; override to implement

return true;

}

Error ChildProcess::run()

{

// declarations

PidType pid = 0;

int fdInput[2] = {0,0};

int fdOutput[2] = {0,0};

int fdError[2] = {0,0};

int fdCloseFd[2] = {0,0};

int fdMaster = 0;

// build args (on heap so they stay around after exec)

// create set of args to pass (needs to include the cmd)

// this is done before calling fork as it is unsafe to use fork in multithreaded programs

// as any calls to malloc could potentially deadlock the child

std::vector<std::string> args;

args.push_back(exe_);

args.insert(args.end(), args_.begin(), args_.end());

using core::system::ProcessArgs;

ProcessArgs* pProcessArgs = new ProcessArgs(args);

ProcessArgs* pEnvironment = nullptr;

// get rlimit for max files

// in the thread-safe fork approach, this needs to be provided

// to the child to properly close its files in an async-safe way

RLimitType soft, hard;

Error error = core::system::getResourceLimit(core::system::FilesLimit, &soft, &hard);

if (error)

return error;

if (options_.environment)

{

// build env (on heap, see comment above)

std::vector<std::string> env;

const Options& options = options_.environment.get();

for (Options::const_iterator

it = options.begin(); it != options.end(); ++it)

{

env.push_back(it->first + "=" + it->second);

}

pEnvironment = new ProcessArgs(env);

}

boost::optional<uid_t> runAsUser;

if (options_.threadSafe && !options_.runAsUser.empty())

{

// fetch the user to switch to before forking, as the method is not

// async signal safe and could cause lockups

core::system::User user;

if (options_.runAsUser == "root")

error = User::getUserFromIdentifier(0, user);

else

error = User::getUserFromIdentifier(options_.runAsUser, user);

if (error)

return error;

runAsUser = user.getUserId();

}

if (options_.threadSafe && options_.pseudoterminal)

{

return systemError(boost::system::errc::operation_not_supported,

"Usage of threadSafe and pseudoterminal options together is not supported",

ERROR_LOCATION);

}

// pseudoterminal mode: fork using the special forkpty call

if (options_.pseudoterminal)

{

char* nullName = nullptr;

struct termios* nullTermp = nullptr;

struct winsize winSize;

winSize.ws_col = options_.pseudoterminal.get().cols;

winSize.ws_row = options_.pseudoterminal.get().rows;

winSize.ws_xpixel = 0;

winSize.ws_ypixel = 0;

Error error = posix::posixCall<PidType>(

boost::bind(::forkpty, &fdMaster, nullName, nullTermp, &winSize),

ERROR_LOCATION,

&pid);

if (error)

return error;

}

// standard mode: use conventional fork + stream redirection

else

{

// standard input

Error error = posix::posixCall<int>(boost::bind(::pipe, fdInput), ERROR_LOCATION);

if (error)

return error;

// standard output

error = posix::posixCall<int>(boost::bind(::pipe, fdOutput), ERROR_LOCATION);

if (error)

{

closePipe(fdInput, ERROR_LOCATION);

return error;

}

// standard error

error = posix::posixCall<int>(boost::bind(::pipe, fdError), ERROR_LOCATION);

if (error)

{

closePipe(fdInput, ERROR_LOCATION);

closePipe(fdOutput, ERROR_LOCATION);

return error;

}

// close fd communication channel - only used in threadsafe mode

if (options_.threadSafe)

{

error = posix::posixCall<int>(boost::bind(::pipe, fdCloseFd), ERROR_LOCATION);

if (error)

{

closePipe(fdInput, ERROR_LOCATION);

closePipe(fdOutput, ERROR_LOCATION);

closePipe(fdError, ERROR_LOCATION);

return error;

}

// fork

error = posix::posixCall<PidType>(::fork, ERROR_LOCATION, &pid);

if (error)

{

closePipe(fdInput, ERROR_LOCATION);

closePipe(fdOutput, ERROR_LOCATION);

closePipe(fdError, ERROR_LOCATION);

return error;

}

// child

if (pid == 0)

{

// NOTE: within the child we want to make sure in all cases that

// we call ::execv to execute the program. as a result if any

// errors occur while we are setting up for the ::execv we log

// and continue rather than calling ::exit (we do this to avoid

// strange error conditions related to global c++ objects being

// torn down in a non-standard sequence).

if (!options_.threadSafe)

{

// note: forking is dangerous in a multithreaded environment

// the following code uses functions that are not async signal-safe

// (see http://man7.org/linux/man-pages/man7/signal-safety.7.html)

// if you spawn children within a multithreaded process, you MUST

// set threadSafe to true on process options, which provides much less

// functionality but guarantees that the child will not hang

// change user here if requested

if (!options_.runAsUser.empty())

{

// restore root

Error error = core::system::restorePriv();

if (error)

LOG_ERROR(error);

if (options_.runAsUser != "root")

{

// switch user if not root

error = core::system::permanentlyDropPriv(options_.runAsUser);

if (error)

LOG_ERROR(error);

}

// check for an onAfterFork function

if (options_.onAfterFork)

options_.onAfterFork();

// if we didn't create a pseudoterminal then check the detachSession

// and terminateChildren options to see whether we need to setsid

// or setpgid(0,0). we skip the check for pseudoterminals because

// forkpty calls setsid internally

if (!options_.pseudoterminal)

{

// If options.detachSession is requested then separate.

if (options_.detachSession)

{

if (::setsid() == -1)

{

LOG_ERROR(systemError(errno, ERROR_LOCATION));

// intentionally fail forward (see note above)

}

else if (options_.terminateChildren)

{

// No need to call ::setpgid(0,0) if ::setsid() was already called

// if options.terminateChildren is requested then obtain a new

// process group (using our own process id). this enables terminate

// to specify -pid to kill which will kill this process and all of

// its children. note that another side-effect is that this process

// will not automatically die with its parent, so the parent

// may want to kill all children from the processSupervisor on exit

if (::setpgid(0,0) == -1)

{

LOG_ERROR(systemError(errno, ERROR_LOCATION));

// intentionally fail forward (see note above)

}

// clear the child signal mask

Error error = core::system::clearSignalMask();

if (error)

{

LOG_ERROR(error);

// intentionally fail forward (see note above)

}

// pseudoterminal mode: file descriptor work is already handled

// by forkpty, all we need to do is configure terminal behavior

if (options_.pseudoterminal)

{

// get current attributes

struct termios termp;

Error error = posix::posixCall<int>(

boost::bind(::tcgetattr, STDIN_FILENO, &termp),

ERROR_LOCATION);

if (!error)

{

if (!options_.smartTerminal)

{

// Specify raw mode; not doing this for terminal (versus dumb

// shell) because on Linux, it broke things like "passwd"

// command's ability to collect passwords).

::cfmakeraw(&termp);

}

else

{

// for smart terminals we need to echo back the user input

termp.c_lflag |= ECHO;

termp.c_oflag |= OPOST|ONLCR;

// Turn off XON/XOFF flow control so Ctrl+S can be used by

// the shell command-line editing instead of suspending output.

termp.c_iflag &= ~(IXON|IXOFF);

}

// Don't ignore signals -- this is done

// so we can send Ctrl-C for interrupts

termp.c_lflag |= ISIG;

// set attribs

safePosixCall<int>(

boost::bind(::tcsetattr, STDIN_FILENO, TCSANOW, &termp),

ERROR_LOCATION);

// save the VINTR character

pImpl_->ctrlC = termp.c_cc[VINTR];

}

else

{

LOG_ERROR(error);

}

// standard mode: close/redirect pipes

else

{

// close unused pipes -- intentionally fail forward (see note above)

closePipe(fdInput[WRITE], ERROR_LOCATION);

closePipe(fdOutput[READ], ERROR_LOCATION);

closePipe(fdError[READ], ERROR_LOCATION);

// wire standard streams (intentionally fail forward)

safePosixCall<int>(boost::bind(::dup2, fdInput[READ], STDIN_FILENO),

ERROR_LOCATION);

safePosixCall<int>(boost::bind(::dup2, fdOutput[WRITE], STDOUT_FILENO),

ERROR_LOCATION);

safePosixCall<int>(

boost::bind(::dup2,

options_.redirectStdErrToStdOut ? fdOutput[WRITE]

: fdError[WRITE],

STDERR_FILENO),

ERROR_LOCATION);

}

// close all open file descriptors other than std streams

error = core::system::closeNonStdFileDescriptors();

if (error)

{

LOG_ERROR(error);

// intentionally fail forward (see note above)

}

if (!options_.workingDir.isEmpty())

{

if (::chdir(options_.workingDir.getAbsolutePath().c_str()))

{

std::string message = "Error changing directory: '";

message += options_.workingDir.getAbsolutePath().c_str();

message += "'";

LOG_ERROR(systemError(errno, message.c_str(), ERROR_LOCATION));

}

else

{

// note: forking is dangerous in a multithreaded environment (see note above)

// this block must ONLY use async signal-safe functions and CANNOT

// dynamically allocate ANY memory or take locks of any kind

// if an error occurs, we exit immediately as this is a critical error

// we use the form of exit, _exit, which forcefully tears down the process

// and does not attempt to run c++ cleanup code (as noted problematic above)

if (runAsUser)

{

if (signal_safe::permanentlyDropPriv(runAsUser.get()) == -1)

::_exit(errno);

}

if (options_.detachSession)

{

if (::setsid() == -1)

::_exit(errno);

}

else if (options_.terminateChildren)

{

if (::setpgid(0,0) == -1)

::_exit(errno);

}

// clear signal mask so that child process does not unintentionally

// block any signals that our parent is blocking

if (signal_safe::clearSignalMask() != 0)

::_exit(errno);

// close pipe end that we do not need

// this is not critical and as such, is best effort

// no error checking is done as a result

::close(fdInput[WRITE]);

::close(fdOutput[READ]);

::close(fdError[READ]);

::close(fdCloseFd[WRITE]);

// wire standard streams

int result = ::dup2(fdInput[READ], STDIN_FILENO);

if (result == -1)

::_exit(errno);

result = ::dup2(fdOutput[WRITE], STDOUT_FILENO);

if (result == -1)

::_exit(errno);

result = ::dup2(options_.redirectStdErrToStdOut ? fdOutput[WRITE] : fdError[WRITE], STDERR_FILENO);

if (result == -1)

::_exit(errno);

// close inherited file descriptors - this prevents

// the child from clobbering the parent's FDs

// and actually prevents potential missed child exits caused by

// clobbering of FDs affecting epoll calls

signal_safe::closeFileDescriptorsFromParent(fdCloseFd[READ], STDERR_FILENO+1, hard);

::close(fdCloseFd[READ]);

}

if (options_.exitWithParent)

{

#ifndef __APPLE__

// set a bit indicating we want to die when our parent dies

if (::prctl(PR_SET_PDEATHSIG, SIGTERM) == -1)

LOG_ERROR(systemError(errno, ERROR_LOCATION));

#endif

}

if (options_.environment)

{

// execute

::execve(exe_.c_str(), pProcessArgs->args(), pEnvironment->args());

}

else

{

// execute

::execv(exe_.c_str(), pProcessArgs->args());

}

if (!options_.threadSafe)

{

// in the normal case control should never return from execv (it starts

// anew at main of the process pointed to by path). therefore, if we get

// here then there was an error

Error error = systemError(errno, ERROR_LOCATION);

error.addProperty("exe", exe_);

LOG_ERROR(error);

::exit(EXIT_FAILURE);

}

else

::_exit(errno);

}

// parent

else

{

// pseudoterminal mode: wire input/output streams to fdMaster

// returned from forkpty

if (options_.pseudoterminal)

{

// record masterFd as our handles

pImpl_->init(pid, fdMaster);

}

// standard mode: close unused pipes & wire streams to appropriate fds

else

{

// close unused pipes

closePipe(fdInput[READ], ERROR_LOCATION);

closePipe(fdOutput[WRITE], ERROR_LOCATION);

closePipe(fdError[WRITE], ERROR_LOCATION);

if (options_.threadSafe)

{

closePipe(fdCloseFd[READ], ERROR_LOCATION);

}

// record pipe handles

pImpl_->init(pid, fdInput[WRITE], fdOutput[READ], fdError[READ]);

}

delete pProcessArgs;

delete pEnvironment;

if (options_.threadSafe)

{

// send the list of the child proc's fds to the child so

// it can properly close its unneeded fds in a fast manner

Error error = closeChildFileDescriptorsFrom(pid, fdCloseFd[WRITE], STDERR_FILENO+1);

if (error)

{

// we simply log the error instead of returning it because it did not prevent

// us from spawning the process

LOG_ERROR(error);

}

closePipe(fdCloseFd[WRITE], ERROR_LOCATION);

}

return Success();

}

// keep compiler happy

return Success();

}

Error SyncChildProcess::readStdOut(std::string* pOutput)

{

return readPipe(pImpl_->fdStdout, pOutput);

}

Error SyncChildProcess::readStdErr(std::string* pOutput)

{

return readPipe(pImpl_->fdStderr, pOutput);

}

Error SyncChildProcess::waitForExit(int* pExitStatus)

{

// blocking wait for exit

int status;

PidType result = posix::posixCall<PidType>(

boost::bind(::waitpid, pImpl_->pid, &status, 0));

// always close all of the pipes

pImpl_->closeAll(ERROR_LOCATION);

// check result

if (result == -1)

{

*pExitStatus = -1;

if (errno == ECHILD) // carve out for child already reaped

return Success();

else

return systemError(errno, ERROR_LOCATION);

}

else

{

*pExitStatus = resolveExitStatus(status);

return Success();

}

struct AsyncChildProcess::AsyncImpl

{

AsyncImpl()

: calledOnStarted_(false),

finishedStdout_(false),

finishedStderr_(false),

exited_(false)

{

}

bool calledOnStarted_;

bool finishedStdout_;

bool finishedStderr_;

bool exited_;

boost::scoped_ptr<ChildProcessSubprocPoll> pSubprocPoll_;

};

AsyncChildProcess::AsyncChildProcess(const std::string& exe,

const std::vector<std::string>& args,

const ProcessOptions& options)

: ChildProcess(), pAsyncImpl_(new AsyncImpl())

{

init(exe, args, options);

if (!options.stdOutFile.isEmpty() || !options.stdErrFile.isEmpty())

{

LOG_WARNING_MESSAGE(

"stdOutFile/stdErrFile options cannot be used with runProgram");

}

AsyncChildProcess::AsyncChildProcess(const std::string& command,

const ProcessOptions& options)

: ChildProcess(), pAsyncImpl_(new AsyncImpl())

{

init(command, options);

}

AsyncChildProcess::AsyncChildProcess(const ProcessOptions& options)

: ChildProcess(), pAsyncImpl_(new AsyncImpl())

{

init(options);

}

AsyncChildProcess::~AsyncChildProcess()

{

}

Error AsyncChildProcess::terminate()

{

#ifndef __APPLE__

// On Linux only do this if dealing with a Terminal-pane process.

// This is to reduce scope of this change for 1.1

// TODO: review post 1.1

if (options().smartTerminal)

{

#endif

if (options().pseudoterminal)

{

pAsyncImpl_->finishedStderr_ = true;

pAsyncImpl_->finishedStdout_ = true;

}

#ifndef __APPLE__

}

#endif

return ChildProcess::terminate();

}

bool AsyncChildProcess::hasNonIgnoredSubprocess() const

{

if (pAsyncImpl_->pSubprocPoll_)

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rstudio/src/cpp/core/system/PosixChildProcess.cpp at main · ssh352/rstudio · GitHub

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