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-rw-r--r--butl/buildfile6
-rw-r--r--butl/fdstream21
-rw-r--r--butl/fdstream.cxx137
-rw-r--r--butl/process-details49
-rw-r--r--butl/process.cxx316
5 files changed, 373 insertions, 156 deletions
diff --git a/butl/buildfile b/butl/buildfile
index 090f9ed..0aa0aae 100644
--- a/butl/buildfile
+++ b/butl/buildfile
@@ -2,7 +2,7 @@
# copyright : Copyright (c) 2014-2017 Code Synthesis Ltd
# license : MIT; see accompanying LICENSE file
-lib{butl}: \
+lib{butl}: \
{hxx cxx}{ base64 } \
{hxx cxx}{ char-scanner } \
{hxx }{ const-ptr } \
@@ -21,6 +21,7 @@ lib{butl}: \
{hxx }{ path-map } \
{hxx txx }{ prefix-map } \
{hxx ixx cxx}{ process } \
+ {hxx }{ process-details } \
{hxx cxx}{ sha256 } \
{hxx }{ small-vector } \
{hxx txx }{ string-table } \
@@ -66,6 +67,9 @@ lib{butl}: cxx.export.poptions = "-I$src_root"
liba{butl}: cxx.export.poptions += -DLIBBUTL_STATIC
libs{butl}: cxx.export.poptions += -DLIBBUTL_SHARED
+if ($cxx.target.class != "windows")
+ cxx.libs += -lpthread
+
# Install into the butl/ subdirectory of, say, /usr/include/.
#
install.include = $install.include/butl/
diff --git a/butl/fdstream b/butl/fdstream
index 8d6385f..6697dd9 100644
--- a/butl/fdstream
+++ b/butl/fdstream
@@ -487,7 +487,9 @@ namespace butl
// Windows permissions other than ru and wu are unlikelly to have effect.
//
// Also note that on POSIX the FD_CLOEXEC flag is set for the file descriptor
- // to prevent its leakage into child processes.
+ // to prevent its leakage into child processes. On Windows, for the same
+ // purpose, the _O_NOINHERIT flag is set. Note that the process class, that
+ // passes such a descriptor to the child, makes it inheritable for a while.
//
LIBBUTL_EXPORT auto_fd
fdopen (const char*,
@@ -516,9 +518,16 @@ namespace butl
// Note that on POSIX the FD_CLOEXEC flag is set for the new descriptor if it
// is present for the source one. That's in contrast to POSIX dup() that
// doesn't copy file descriptor flags. Also note that duplicating descriptor
- // and setting the flag is not an atomic operation.
+ // and setting the flag is not an atomic operation generally, but it is in
+ // regards to child process spawning (to prevent file descriptor leakage into
+ // a child process).
//
- // @@ Should we copy HANDLE_FLAG_INHERIT flag on Windows as well?
+ // Note that on Windows the _O_NOINHERIT flag is set for the new descriptor
+ // if it is present for the source one. That's in contrast to Windows _dup()
+ // that doesn't copy the flag. Also note that duplicating descriptor and
+ // setting the flag is not an atomic operation generally, but it is in
+ // regards to child process spawning (to prevent file descriptor leakage into
+ // a child process).
//
LIBBUTL_EXPORT auto_fd
fddup (int fd);
@@ -608,8 +617,10 @@ namespace butl
// automatically closed by the child process to prevent undesired behaviors
// (such as child deadlock on read from a pipe due to the write-end leakage
// into the child process). Opening pipe and setting the flag is not an
- // atomic operation. Also note that you don't need to reset the flag for a
- // pipe end being passed to the process class ctor.
+ // atomic operation generally, but it is in regards to child process spawning
+ // (to prevent file descriptor leakage into child processes spawned from
+ // other threads). Also note that you don't need to reset the flag for a pipe
+ // end being passed to the process class ctor.
//
LIBBUTL_EXPORT fdpipe
fdopen_pipe (fdopen_mode = fdopen_mode::none);
diff --git a/butl/fdstream.cxx b/butl/fdstream.cxx
index bdbfa08..41dd1f5 100644
--- a/butl/fdstream.cxx
+++ b/butl/fdstream.cxx
@@ -12,8 +12,10 @@
# include <sys/stat.h> // S_I*
# include <sys/types.h> // off_t
#else
+# include <butl/win32-utility>
+
# include <io.h> // _close(), _read(), _write(), _setmode(), _sopen(),
- // _lseek(), _dup(), _pipe()
+ // _lseek(), _dup(), _pipe(), _get_osfhandle()
# include <share.h> // _SH_DENYNO
# include <stdio.h> // _fileno(), stdin, stdout, stderr
# include <fcntl.h> // _O_*
@@ -32,8 +34,14 @@
#include <type_traits>
#include <system_error>
+#include <butl/process-details>
+
using namespace std;
+#ifdef _WIN32
+using namespace butl::win32;
+#endif
+
namespace butl
{
// throw_ios_failure
@@ -63,7 +71,7 @@ namespace butl
throw ios_base::failure (m != nullptr ? m : e.message ().c_str ());
}
- inline void
+ static inline void
throw_ios_failure (int ev, const char* m = nullptr)
{
error_code ec (ev, system_category ());
@@ -708,6 +716,10 @@ namespace butl
pass_perm = false;
}
+ // Make sure the file descriptor is not inheritable by default.
+ //
+ of |= _O_NOINHERIT;
+
int fd (pass_perm
? _sopen (f, of, _SH_DENYNO, pf)
: _sopen (f, of, _SH_DENYNO));
@@ -739,35 +751,48 @@ namespace butl
return auto_fd (fd);
}
+#ifndef _WIN32
+
auto_fd
fddup (int fd)
{
-#ifndef _WIN32
- int nfd (dup (fd));
+ // dup() doesn't copy FD_CLOEXEC flag, so we need to do it ourselves. Note
+ // that the new descriptor can leak into child processes before we copy the
+ // flag. To prevent this we will acquire the process_spawn_mutex (see
+ // process-details header) prior to duplicating the descriptor. Also note
+ // there is dup3() (available on Linux and FreeBSD but not on Max OS) that
+ // takes flags, but it's usage tends to be hairy (need to preopen a dummy
+ // file descriptor to pass as a second argument).
+ //
+ auto dup = [fd] () -> auto_fd
+ {
+ auto_fd nfd (::dup (fd));
+ if (nfd.get () == -1)
+ throw_ios_failure (errno);
+
+ return nfd;
+ };
int f (fcntl (fd, F_GETFD));
if (f == -1)
throw_ios_failure (errno);
- if ((f & FD_CLOEXEC) != 0)
- {
- f = fcntl (nfd, F_GETFD);
- if (f == -1 || fcntl (nfd, F_SETFD, f | FD_CLOEXEC) == -1)
- throw_ios_failure (errno);
- }
+ // If the source descriptor has no FD_CLOEXEC flag set then no flag copy is
+ // required (as the duplicate will have no flag by default).
+ //
+ if ((f & FD_CLOEXEC) == 0)
+ return dup ();
-#else
- int nfd (_dup (fd));
-#endif
+ slock l (process_spawn_mutex);
+ auto_fd nfd (dup ());
- if (nfd == -1)
+ f = fcntl (nfd.get (), F_GETFD);
+ if (f == -1 || fcntl (nfd.get (), F_SETFD, f | FD_CLOEXEC) == -1)
throw_ios_failure (errno);
- return auto_fd (nfd);
+ return nfd;
}
-#ifndef _WIN32
-
bool
fdclose (int fd) noexcept
{
@@ -836,10 +861,20 @@ namespace butl
{
assert (m == fdopen_mode::none || m == fdopen_mode::binary);
+ // Note that the pipe file descriptors can leak into child processes before
+ // we set FD_CLOEXEC flag for them. To prevent this we will acquire the
+ // process_spawn_mutex (see process-details header) prior to creating the
+ // pipe. Also note there is pipe2() (available on Linux and FreeBSD but not
+ // on Max OS) that takes flags.
+ //
+ slock l (process_spawn_mutex);
+
int pd[2];
if (pipe (pd) == -1)
throw_ios_failure (errno);
+ fdpipe r {auto_fd (pd[0]), auto_fd (pd[1])};
+
for (size_t i (0); i < 2; ++i)
{
int f (fcntl (pd[i], F_GETFD));
@@ -847,11 +882,62 @@ namespace butl
throw_ios_failure (errno);
}
- return {auto_fd (pd[0]), auto_fd (pd[1])};
+ return r;
}
#else
+ auto_fd
+ fddup (int fd)
+ {
+ // _dup() doesn't copy _O_NOINHERIT flag, so we need to do it ourselves.
+ // Note that the new descriptor can leak into child processes before we
+ // copy the flag. To prevent this we will acquire the process_spawn_mutex
+ // (see process-details header) prior to duplicating the descriptor.
+ //
+ // We can not ammend file descriptors directly (nor obtain the flag value),
+ // so need to resolve them to Windows HANDLE first. Such handles are closed
+ // either when CloseHandle() is called for them or when _close() is called
+ // for the associated file descriptors. Make sure that either the original
+ // file descriptor or the resulting HANDLE is closed but not both of them.
+ //
+ auto handle = [] (int fd) -> HANDLE
+ {
+ HANDLE h (reinterpret_cast<HANDLE> (_get_osfhandle (fd)));
+ if (h == INVALID_HANDLE_VALUE)
+ throw_ios_failure (EIO, "unable to obtain file handle");
+
+ return h;
+ };
+
+ auto dup = [fd] () -> auto_fd
+ {
+ auto_fd nfd (_dup (fd));
+ if (nfd.get () == -1)
+ throw_ios_failure (errno);
+
+ return nfd;
+ };
+
+ DWORD f;
+ if (!GetHandleInformation (handle (fd), &f))
+ throw_ios_failure (EIO, last_error_msg ().c_str ());
+
+ // If the source handle is inheritable then no flag copy is required (as
+ // the duplicate handle will be inheritable by default).
+ //
+ if (f & HANDLE_FLAG_INHERIT)
+ return dup ();
+
+ slock l (process_spawn_mutex);
+
+ auto_fd nfd (dup ());
+ if (!SetHandleInformation (handle (nfd.get ()), HANDLE_FLAG_INHERIT, 0))
+ throw_ios_failure (EIO, last_error_msg ().c_str ());
+
+ return nfd;
+ }
+
bool
fdclose (int fd) noexcept
{
@@ -864,7 +950,7 @@ namespace butl
// No need to translate \r\n before sending it to void.
//
if (!temp)
- return _sopen ("nul", _O_RDWR | _O_BINARY, _SH_DENYNO);
+ return _sopen ("nul", _O_RDWR | _O_BINARY | _O_NOINHERIT, _SH_DENYNO);
try
{
@@ -873,11 +959,12 @@ namespace butl
//
path p (path::temp_path ("null")); // Can throw.
return _sopen (p.string ().c_str (),
- (_O_CREAT |
- _O_RDWR |
- _O_BINARY | // Don't translate.
- _O_TEMPORARY | // Remove on close.
- _O_SHORT_LIVED), // Don't flush to disk.
+ (_O_CREAT |
+ _O_RDWR |
+ _O_BINARY | // Don't translate.
+ _O_TEMPORARY | // Remove on close.
+ _O_SHORT_LIVED | // Don't flush to disk.
+ _O_NOINHERIT), // Don't inherit by child process.
_SH_DENYNO,
_S_IREAD | _S_IWRITE);
}
@@ -908,6 +995,8 @@ namespace butl
if (m != fdstream_mode::binary && m != fdstream_mode::text)
throw invalid_argument ("invalid translation mode");
+ // Note that _setmode() preserves the _O_NOINHERIT flag value.
+ //
int r (_setmode (fd, m == fdstream_mode::binary ? _O_BINARY : _O_TEXT));
if (r == -1)
throw_ios_failure (errno);
diff --git a/butl/process-details b/butl/process-details
new file mode 100644
index 0000000..b07ceff
--- /dev/null
+++ b/butl/process-details
@@ -0,0 +1,49 @@
+// file : butl/process-details -*- C++ -*-
+// copyright : Copyright (c) 2014-2017 Code Synthesis Ltd
+// license : MIT; see accompanying LICENSE file
+
+#ifndef BUTL_PROCESS_DETAILS
+#define BUTL_PROCESS_DETAILS
+
+#include <mutex>
+
+#include <butl/ft/shared_mutex>
+#if defined(__cpp_lib_shared_mutex) || defined(__cpp_lib_shared_timed_mutex)
+# include <shared_mutex>
+#endif
+
+namespace butl
+{
+#if defined(__cpp_lib_shared_mutex)
+ using shared_mutex = std::shared_mutex;
+ using ulock = std::unique_lock<shared_mutex>;
+ using slock = std::shared_lock<shared_mutex>;
+#elif defined(__cpp_lib_shared_timed_mutex)
+ using shared_mutex = std::shared_timed_mutex;
+ using ulock = std::unique_lock<shared_mutex>;
+ using slock = std::shared_lock<shared_mutex>;
+#else
+ // Because we have this fallback, we need to be careful not to create
+ // multiple shared locks in the same thread.
+ //
+ struct shared_mutex: std::mutex
+ {
+ using mutex::mutex;
+
+ void lock_shared () { lock (); }
+ void try_lock_shared () { try_lock (); }
+ void unlock_shared () { unlock (); }
+ };
+
+ using ulock = std::unique_lock<shared_mutex>;
+ using slock = ulock;
+#endif
+
+ // Mutex that is acquired to make a sequence of operations atomic in regards
+ // to child process spawning. Must be aquired for exclusive access for child
+ // process startup, and for shared access otherwise. Defined in process.cxx.
+ //
+ extern shared_mutex process_spawn_mutex;
+}
+
+#endif // BUTL_PROCESS_DETAILS
diff --git a/butl/process.cxx b/butl/process.cxx
index 892e930..189d1ee 100644
--- a/butl/process.cxx
+++ b/butl/process.cxx
@@ -27,7 +27,7 @@
# include <cstdlib> // __argv[]
-# include <butl/win32-utility>
+# include <butl/small-vector>
#endif
#include <errno.h>
@@ -39,8 +39,9 @@
#include <utility> // move()
#include <ostream>
-#include <butl/utility> // casecmp()
-#include <butl/fdstream> // fdnull()
+#include <butl/utility> // casecmp()
+#include <butl/fdstream> // fdnull()
+#include <butl/process-details>
using namespace std;
@@ -50,6 +51,8 @@ using namespace butl::win32;
namespace butl
{
+ shared_mutex process_spawn_mutex;
+
// process
//
static process_path
@@ -256,7 +259,7 @@ namespace butl
fdpipe in_ofd;
fdpipe in_efd;
- auto fail = [](bool child) {throw process_error (errno, child);};
+ auto fail = [] (bool child) {throw process_error (errno, child);};
auto open_pipe = [] () -> fdpipe
{
@@ -303,65 +306,68 @@ namespace butl
else if (err == -2)
in_efd.out = open_null ();
- handle = fork ();
+ {
+ ulock l (process_spawn_mutex); // Will not be released in child.
+ handle = fork ();
- if (handle == -1)
- fail (false);
+ if (handle == -1)
+ fail (false);
- if (handle == 0)
- {
- // Child.
- //
- // Duplicate the user-supplied (fd > -1) or the created pipe descriptor
- // to the standard stream descriptor (read end for STDIN_FILENO, write
- // end otherwise). Close the the pipe afterwards.
- //
- auto duplicate = [&fail](int sd, int fd, fdpipe& pd)
+ if (handle == 0)
{
- if (fd == -1 || fd == -2)
- fd = (sd == STDIN_FILENO ? pd.in : pd.out).get ();
+ // Child.
+ //
+ // Duplicate the user-supplied (fd > -1) or the created pipe descriptor
+ // to the standard stream descriptor (read end for STDIN_FILENO, write
+ // end otherwise). Close the the pipe afterwards.
+ //
+ auto duplicate = [&fail] (int sd, int fd, fdpipe& pd)
+ {
+ if (fd == -1 || fd == -2)
+ fd = (sd == STDIN_FILENO ? pd.in : pd.out).get ();
- assert (fd > -1);
- if (dup2 (fd, sd) == -1)
- fail (true);
+ assert (fd > -1);
+ if (dup2 (fd, sd) == -1)
+ fail (true);
- pd.in.reset (); // Silently close.
- pd.out.reset (); // Silently close.
- };
+ pd.in.reset (); // Silently close.
+ pd.out.reset (); // Silently close.
+ };
- if (in != STDIN_FILENO)
- duplicate (STDIN_FILENO, in, out_fd);
+ if (in != STDIN_FILENO)
+ duplicate (STDIN_FILENO, in, out_fd);
- // If stdout is redirected to stderr (out == 2) we need to duplicate it
- // after duplicating stderr to pickup the proper fd. Otherwise keep the
- // "natual" order of duplicate() calls, so if stderr is redirected to
- // stdout it picks up the proper fd as well.
- //
- if (out == STDERR_FILENO)
- {
- if (err != STDERR_FILENO)
- duplicate (STDERR_FILENO, err, in_efd);
+ // If stdout is redirected to stderr (out == 2) we need to duplicate it
+ // after duplicating stderr to pickup the proper fd. Otherwise keep the
+ // "natual" order of duplicate() calls, so if stderr is redirected to
+ // stdout it picks up the proper fd as well.
+ //
+ if (out == STDERR_FILENO)
+ {
+ if (err != STDERR_FILENO)
+ duplicate (STDERR_FILENO, err, in_efd);
- if (out != STDOUT_FILENO)
- duplicate (STDOUT_FILENO, out, in_ofd);
- }
- else
- {
- if (out != STDOUT_FILENO)
- duplicate (STDOUT_FILENO, out, in_ofd);
+ if (out != STDOUT_FILENO)
+ duplicate (STDOUT_FILENO, out, in_ofd);
+ }
+ else
+ {
+ if (out != STDOUT_FILENO)
+ duplicate (STDOUT_FILENO, out, in_ofd);
- if (err != STDERR_FILENO)
- duplicate (STDERR_FILENO, err, in_efd);
- }
+ if (err != STDERR_FILENO)
+ duplicate (STDERR_FILENO, err, in_efd);
+ }
- // Change current working directory if requested.
- //
- if (cwd != nullptr && *cwd != '\0' && chdir (cwd) != 0)
- fail (true);
+ // Change current working directory if requested.
+ //
+ if (cwd != nullptr && *cwd != '\0' && chdir (cwd) != 0)
+ fail (true);
- if (execv (pp.effect_string (), const_cast<char**> (&args[0])) == -1)
- fail (true);
- }
+ if (execv (pp.effect_string (), const_cast<char**> (&args[0])) == -1)
+ fail (true);
+ }
+ } // Release the lock in parent.
assert (handle != 0); // Shouldn't get here unless in the parent process.
@@ -798,6 +804,61 @@ namespace butl
HANDLE handle_;
};
+ // Make handles inheritable. The process_spawn_mutex must be pre-acquired for
+ // exclusive access. Revert handles inheritability state in destructor.
+ //
+ // There is a period of time when the process ctor makes file handles it
+ // passes to the child to be inheritable, that otherwise are not inheritable
+ // by default. During this time these handles can also be inherited by other
+ // (irrelevant) child processed spawned from other threads. That can lead to
+ // some unwanted consequences, such as inability to delete a file
+ // corresponding to such a handle until all childs, that the handle leaked
+ // into, terminate. To prevent this behavior the specific sequence of steps
+ // (that involves making handles inheritable, spawning process and reverting
+ // handles to non-inheritable state back) will be performed after aquiring
+ // the process_spawn_mutex (that is released afterwards).
+ //
+ class inheritability_guard
+ {
+ public:
+ // Require the proof that the mutex is pre-acquired for exclusive access.
+ //
+ inheritability_guard (const ulock&) {}
+
+ ~inheritability_guard ()
+ {
+ for (auto h: handles_)
+ inheritable (h, false); // Can't throw.
+ }
+
+ void
+ inheritable (HANDLE h)
+ {
+ inheritable (h, true); // Can throw.
+ handles_.push_back (h);
+ }
+
+ private:
+ void
+ inheritable (HANDLE h, bool state)
+ {
+ if (!SetHandleInformation (
+ h, HANDLE_FLAG_INHERIT, state ? HANDLE_FLAG_INHERIT : 0))
+ {
+ if (state)
+ throw process_error (last_error_msg ());
+
+ // We should be able to successfully reset the HANDLE_FLAG_INHERIT flag
+ // that we successfully set, unless something is severely damaged.
+ //
+ assert (false);
+ }
+ }
+
+ private:
+ small_vector<HANDLE, 3> handles_;
+ };
+
process::
process (const char* cwd,
const process_path& pp, const char* args[],
@@ -862,35 +923,6 @@ namespace butl
else if (err == -2)
in_efd.out = open_null ();
- // Resolve file descriptor to HANDLE and make sure it is inherited. Note
- // that the handle is closed either when CloseHandle() is called for it or
- // when _close() is called for the associated file descriptor. Make sure
- // that either the original file descriptor or the resulting HANDLE is
- // closed but not both of them.
- //
- auto get_osfhandle = [&fail](int fd) -> HANDLE
- {
- HANDLE h (reinterpret_cast<HANDLE> (_get_osfhandle (fd)));
- if (h == INVALID_HANDLE_VALUE)
- fail ("unable to obtain file handle");
-
- // Make the handle inheritable by the child unless it is already
- // inheritable.
- //
- DWORD f;
- if (!GetHandleInformation (h, &f))
- fail ();
-
- // Note that the flag check is essential as SetHandleInformation() fails
- // for standard handles and their duplicates.
- //
- if ((f & HANDLE_FLAG_INHERIT) == 0 &&
- !SetHandleInformation (h, HANDLE_FLAG_INHERIT, HANDLE_FLAG_INHERIT))
- fail ();
-
- return h;
- };
-
// Create the process.
//
@@ -934,58 +966,90 @@ namespace butl
si.cb = sizeof (STARTUPINFO);
si.dwFlags |= STARTF_USESTDHANDLES;
- si.hStdInput = in == -1 || in == -2
- ? get_osfhandle (out_fd.in.get ())
- : in == STDIN_FILENO
- ? GetStdHandle (STD_INPUT_HANDLE)
- : get_osfhandle (in);
-
- si.hStdOutput = out == -1 || out == -2
- ? get_osfhandle (in_ofd.out.get ())
- : out == STDOUT_FILENO
- ? GetStdHandle (STD_OUTPUT_HANDLE)
- : get_osfhandle (out);
-
- si.hStdError = err == -1 || err == -2
- ? get_osfhandle (in_efd.out.get ())
- : err == STDERR_FILENO
- ? GetStdHandle (STD_ERROR_HANDLE)
- : get_osfhandle (err);
-
- // Perform standard stream redirection if requested.
- //
- if (err == STDOUT_FILENO)
- si.hStdError = si.hStdOutput;
- else if (out == STDERR_FILENO)
- si.hStdOutput = si.hStdError;
-
- if (err == STDIN_FILENO ||
- out == STDIN_FILENO ||
- in == STDOUT_FILENO ||
- in == STDERR_FILENO)
- fail ("invalid file descriptor");
-
- if (!CreateProcess (
- pp.effect_string (),
- const_cast<char*> (cmd_line.c_str ()),
- 0, // Process security attributes.
- 0, // Primary thread security attributes.
- true, // Inherit handles.
- 0, // Creation flags.
- 0, // Use our environment.
- cwd != nullptr && *cwd != '\0' ? cwd : nullptr,
- &si,
- &pi))
- fail ();
+ {
+ ulock l (process_spawn_mutex);
+ inheritability_guard ig (l);
+
+ // Resolve file descriptor to HANDLE and make sure it is inherited. Note
+ // that the handle is closed either when CloseHandle() is called for it
+ // or when _close() is called for the associated file descriptor. Make
+ // sure that either the original file descriptor or the resulting HANDLE
+ // is closed but not both of them.
+ //
+ auto get_osfhandle = [&fail, &ig] (int fd) -> HANDLE
+ {
+ HANDLE h (reinterpret_cast<HANDLE> (_get_osfhandle (fd)));
+ if (h == INVALID_HANDLE_VALUE)
+ fail ("unable to obtain file handle");
+
+ // Make the handle inheritable by the child unless it is already
+ // inheritable.
+ //
+ DWORD f;
+ if (!GetHandleInformation (h, &f))
+ fail ();
+
+ // Note that the flag check is essential as SetHandleInformation()
+ // fails for standard handles and their duplicates.
+ //
+ if ((f & HANDLE_FLAG_INHERIT) == 0)
+ ig.inheritable (h);
+
+ return h;
+ };
+
+ si.hStdInput = in == -1 || in == -2
+ ? get_osfhandle (out_fd.in.get ())
+ : (in == STDIN_FILENO
+ ? GetStdHandle (STD_INPUT_HANDLE)
+ : get_osfhandle (in));
+
+ si.hStdOutput = out == -1 || out == -2
+ ? get_osfhandle (in_ofd.out.get ())
+ : (out == STDOUT_FILENO
+ ? GetStdHandle (STD_OUTPUT_HANDLE)
+ : get_osfhandle (out));
+
+ si.hStdError = err == -1 || err == -2
+ ? get_osfhandle (in_efd.out.get ())
+ : (err == STDERR_FILENO
+ ? GetStdHandle (STD_ERROR_HANDLE)
+ : get_osfhandle (err));
+
+ // Perform standard stream redirection if requested.
+ //
+ if (err == STDOUT_FILENO)
+ si.hStdError = si.hStdOutput;
+ else if (out == STDERR_FILENO)
+ si.hStdOutput = si.hStdError;
+
+ if (err == STDIN_FILENO ||
+ out == STDIN_FILENO ||
+ in == STDOUT_FILENO ||
+ in == STDERR_FILENO)
+ fail ("invalid file descriptor");
+
+ if (!CreateProcess (
+ pp.effect_string (),
+ const_cast<char*> (cmd_line.c_str ()),
+ 0, // Process security attributes.
+ 0, // Primary thread security attributes.
+ true, // Inherit handles.
+ 0, // Creation flags.
+ 0, // Use our environment.
+ cwd != nullptr && *cwd != '\0' ? cwd : nullptr,
+ &si,
+ &pi))
+ fail ();
+ } // Revert handled back to non-inheritable and release the lock.
auto_handle (pi.hThread).reset (); // Close.
- auto_handle process (pi.hProcess);
this->out_fd = move (out_fd.out);
this->in_ofd = move (in_ofd.in);
this->in_efd = move (in_efd.in);
- this->handle = process.release ();
+ this->handle = pi.hProcess;
// 0 has a special meaning denoting a terminated process handle.
//