Invent auto_fd, make use of it in fdstreams and process

10 files changed, 209 insertions, 208 deletions

diff --git a/butl/fdstream b/butl/fdstream
index 2d7fae5..9c7274d 100644
--- a/butl/fdstream
+++ b/butl/fdstream
@@ -8,6 +8,7 @@
 #include <string>
 #include <istream>
 #include <ostream>
+#include <utility> // move()
 #include <cstdint> // uint16_t
 
 #include <butl/export>
@@ -17,6 +18,45 @@
 
 namespace butl
 {
+  // RAII type for file descriptors. Note that failure to close the descriptor
+  // is silently ignored by both the destructor and reset() (thought we could
+  // probably provide the close() function that throws).
+  //
+  // The descriptor can be negative. Such a descriptor is treated as unopened
+  // and is not closed.
+  //
+  struct nullfd_t {constexpr explicit nullfd_t (int) {}};
+  constexpr const nullfd_t nullfd (-1);
+
+  class auto_fd
+  {
+  public:
+    auto_fd (nullfd_t = nullfd): fd_ (-1) {}
+
+    explicit
+    auto_fd (int fd) noexcept: fd_ (fd) {}
+
+    auto_fd (auto_fd&& fd) noexcept: fd_ (fd.release ()) {}
+    auto_fd& operator= (auto_fd&&) noexcept;
+
+    auto_fd (const auto_fd&) = delete;
+    auto_fd& operator= (const auto_fd&) = delete;
+
+    ~auto_fd () noexcept {reset ();}
+
+    int
+    get () const noexcept {return fd_;}
+
+    int
+    release () noexcept;
+
+    void
+    reset (int fd = -1) noexcept;
+
+  private:
+    int fd_;
+  };
+
   // An [io]fstream that can be initialized with a file descriptor in addition
   // to a file name and that also by default enables exceptions on badbit and
   // failbit. So instead of a dance like this:
@@ -41,31 +81,26 @@ namespace butl
   // - after catching an exception caused by badbit the stream is no longer
   //   used
   // - not movable, though can be easily supported
-  // - passing to constructor -1 file descriptor is valid and results in the
-  //   creation of an unopened object
+  // - passing to constructor auto_fd with a negative file descriptor is valid
+  //   and results in the creation of an unopened object
   //
   class LIBBUTL_EXPORT fdbuf: public std::basic_streambuf<char>
   {
   public:
-    virtual
-    ~fdbuf ();
     fdbuf () = default;
-    fdbuf (int fd) {if (fd != -1) open (fd);}
-
-    fdbuf (const fdbuf&) = delete;
-    fdbuf& operator= (const fdbuf&) = delete;
+    fdbuf (auto_fd&&);
 
     void
     close ();
 
     void
-    open (int fd);
+    open (auto_fd&&);
 
     bool
-    is_open () const {return fd_ != -1;}
+    is_open () const {return fd_.get () >= 0;}
 
     int
-    fd () const {return fd_;}
+    fd () const {return fd_.get ();}
 
   public:
     using int_type = std::basic_streambuf<char>::int_type;
@@ -101,7 +136,7 @@ namespace butl
     save ();
 
   private:
-    int fd_ = -1;
+    auto_fd fd_;
     char buf_[8192];
     bool non_blocking_ = false;
   };
@@ -164,8 +199,8 @@ namespace butl
   {
   protected:
     fdstream_base () = default;
-    fdstream_base (int fd): buf_ (fd) {}
-    fdstream_base (int, fdstream_mode);
+    fdstream_base (auto_fd&& fd): buf_ (std::move (fd)) {}
+    fdstream_base (auto_fd&&, fdstream_mode);
 
   public:
     int
@@ -191,18 +226,13 @@ namespace butl
   // iofdstream constructors and open() functions that take file path as a
   // const std::string& or const char* may throw the invalid_path exception.
   //
-  // Passing -1 as a file descriptor is valid and results in the creation of
-  // an unopened object.
+  // Passing auto_fd with a negative file descriptor is valid and results in
+  // the creation of an unopened object.
   //
   // Also note that open() and close() functions can be successfully called
   // for an opened and unopened objects respectively. That is in contrast with
   // iofstream that sets failbit in such cases.
   //
-  // @@ Need to make sure performance is on par with fstream on both
-  //    Linux and Windows.
-  //
-  // @@ Do we need to increase default buffer size? Make it customizable?
-  //    Wonder what it is in libstdc++ and MSVC?
 
   // Note that ifdstream destructor will close an open file descriptor but
   // will ignore any errors. To detect such errors, call close() explicitly.
@@ -219,8 +249,8 @@ namespace butl
   //   {
   //     // In case of exception, skip and close input after output.
   //     //
-  //     ifdstream is (pr.in_ofd, fdstream_mode::skip);
-  //     ofdstream os (pr.out_fd);
+  //     ifdstream is (move (pr.in_ofd), fdstream_mode::skip);
+  //     ofdstream os (move (pr.out_fd));
   //
   //     // Write.
   //
@@ -268,17 +298,14 @@ namespace butl
   class LIBBUTL_EXPORT ifdstream: public fdstream_base, public std::istream
   {
   public:
-    // Create an unopened object with iostate = badbit | failbit (we cannot
-    // have the iostate as an argument since it clashes with int fd) To create
-    // an unopened object with non-default exception mask one can do:
-    //
-    // ifdstream (-1, ...);
+    // Create an unopened object.
     //
-    ifdstream ();
+    explicit
+    ifdstream (iostate e = badbit | failbit);
 
     explicit
-    ifdstream (int fd, iostate e = badbit | failbit);
-    ifdstream (int fd, fdstream_mode m, iostate e = badbit | failbit);
+    ifdstream (auto_fd&&, iostate e = badbit | failbit);
+    ifdstream (auto_fd&&, fdstream_mode m, iostate e = badbit | failbit);
 
     explicit
     ifdstream (const char*,
@@ -328,7 +355,7 @@ namespace butl
     open (const path&, fdopen_mode);
 
     void
-    open (int fd) {buf_.open (fd); clear ();}
+    open (auto_fd&& fd) {buf_.open (std::move (fd)); clear ();}
 
     void close ();
     bool is_open () const {return buf_.is_open ();}
@@ -348,17 +375,14 @@ namespace butl
   class LIBBUTL_EXPORT ofdstream: public fdstream_base, public std::ostream
   {
   public:
-    // Create an unopened object with iostate = badbit | failbit (we cannot
-    // have the iostate as an argument since it clashes with int fd). To create
-    // an unopened object with non-default exception mask one can do:
-    //
-    // ofdstream (-1, ...);
+    // Create an unopened object.
     //
-    ofdstream ();
+    explicit
+    ofdstream (iostate e = badbit | failbit);
 
     explicit
-    ofdstream (int fd, iostate e = badbit | failbit);
-    ofdstream (int fd, fdstream_mode m, iostate e = badbit | failbit);
+    ofdstream (auto_fd&&, iostate e = badbit | failbit);
+    ofdstream (auto_fd&&, fdstream_mode m, iostate e = badbit | failbit);
 
     explicit
     ofdstream (const char*,
@@ -408,7 +432,7 @@ namespace butl
     open (const path&, fdopen_mode);
 
     void
-    open (int fd) {buf_.open (fd); clear ();}
+    open (auto_fd&& fd) {buf_.open (std::move (fd)); clear ();}
 
     void close () {if (is_open ()) flush (); buf_.close ();}
     bool is_open () const {return buf_.is_open ();}
@@ -432,8 +456,8 @@ namespace butl
   LIBBUTL_EXPORT ifdstream&
   getline (ifdstream&, std::string&, char delim = '\n');
 
-  // Open a file returning the file descriptor on success and throwing
-  // ios:failure otherwise.
+  // Open a file returning an auto_fd that holds its file descriptor on
+  // success and throwing ios::failure otherwise.
   //
   // The mode argument should have at least one of the in or out flags set.
   // The append and truncate flags are meaningless in the absense of the out
@@ -448,21 +472,21 @@ namespace butl
   // process' umask, so effective permissions are permissions & ~umask. On
   // Windows permissions other than ru and wu are unlikelly to have effect.
   //
-  LIBBUTL_EXPORT int
+  LIBBUTL_EXPORT auto_fd
   fdopen (const char*,
           fdopen_mode,
           permissions = permissions::ru | permissions::wu |
                         permissions::rg | permissions::wg |
                         permissions::ro | permissions::wo);
 
-  LIBBUTL_EXPORT int
+  LIBBUTL_EXPORT auto_fd
   fdopen (const std::string&,
           fdopen_mode,
           permissions = permissions::ru | permissions::wu |
                         permissions::rg | permissions::wg |
                         permissions::ro | permissions::wo);
 
-  LIBBUTL_EXPORT int
+  LIBBUTL_EXPORT auto_fd
   fdopen (const path&,
           fdopen_mode,
           permissions = permissions::ru | permissions::wu |
@@ -510,6 +534,11 @@ namespace butl
   // closed. One difference, however, would be if you were to both write to
   // and read from the descriptor.
   //
+  // @@ You may have noticed that this interface doesn't match fdopen() (it
+  //    does not throw and return int instead of auto_fd). The reason for this
+  //    is process and its need to translate everything to process_error).
+  //    Once we solve that we can clean this up as well.
+  //
 #ifndef _WIN32
   LIBBUTL_EXPORT int
   fdnull () noexcept;
diff --git a/butl/fdstream.cxx b/butl/fdstream.cxx
index 109b041..dbd7767 100644
--- a/butl/fdstream.cxx
+++ b/butl/fdstream.cxx
@@ -71,19 +71,19 @@ namespace butl
   // fdbuf
   //
   fdbuf::
-  ~fdbuf ()
+  fdbuf (auto_fd&& fd)
   {
-    if (is_open ())
-      fdclose (fd_); // Don't check for an error as not much we can do here.
+    if (fd.get () >= 0)
+      open (move (fd));
   }
 
   void fdbuf::
-  open (int fd)
+  open (auto_fd&& fd)
   {
     close ();
 
 #ifndef _WIN32
-    int flags (fcntl (fd, F_GETFL));
+    int flags (fcntl (fd.get (), F_GETFL));
 
     if (flags == -1)
       throw_ios_failure (errno);
@@ -91,21 +91,22 @@ namespace butl
     non_blocking_ = (flags & O_NONBLOCK) == O_NONBLOCK;
 #endif
 
-    fd_ = fd;
     setg (buf_, buf_, buf_);
     setp (buf_, buf_ + sizeof (buf_) - 1); // Keep space for overflow's char.
+
+    fd_ = move (fd);
   }
 
   void fdbuf::
   close ()
   {
-    if (is_open ())
-    {
-      if (!fdclose (fd_))
-        throw_ios_failure (errno);
-
-      fd_ = -1;
-    }
+    // Before we invented auto_fd into fdstreams we keept fdbuf opened on
+    // faulty close attempt. Now fdbuf is always closed by close() function.
+    // This semantics change seems to be the right one as there is no reason to
+    // expect fdclose() to succeed after it has already failed once.
+    //
+    if (is_open () && !fdclose (fd_.release ()))
+      throw_ios_failure (errno);
   }
 
   streamsize fdbuf::
@@ -122,7 +123,7 @@ namespace butl
 #ifndef _WIN32
     if (non_blocking_)
     {
-      ssize_t n (read (fd_, buf_, sizeof (buf_)));
+      ssize_t n (read (fd_.get (), buf_, sizeof (buf_)));
 
       if (n == -1)
       {
@@ -173,9 +174,9 @@ namespace butl
     assert (!non_blocking_);
 
 #ifndef _WIN32
-    ssize_t n (read (fd_, buf_, sizeof (buf_)));
+    ssize_t n (read (fd_.get (), buf_, sizeof (buf_)));
 #else
-    int n (_read (fd_, buf_, sizeof (buf_)));
+    int n (_read (fd_.get (), buf_, sizeof (buf_)));
 #endif
 
     if (n == -1)
@@ -242,9 +243,9 @@ namespace butl
       // expected). This is in contrast with VC's _write() and POSIX's write().
       //
 #ifndef _WIN32
-      ssize_t m (write (fd_, buf_, n));
+      ssize_t m (write (fd_.get (), buf_, n));
 #else
-      int m (_write (fd_, buf_, n));
+      int m (_write (fd_.get (), buf_, n));
 #endif
 
       if (m == -1)
@@ -296,10 +297,10 @@ namespace butl
       // Write both buffered and new data with a single system call.
       //
       iovec iov[2] = {{pbase (), bn}, {const_cast<char*> (s), n}};
-      r = writev (fd_, iov, 2);
+      r = writev (fd_.get (), iov, 2);
     }
     else
-      r = write (fd_, s, n);
+      r = write (fd_.get (), s, n);
 
     if (r == -1)
       throw_ios_failure (errno);
@@ -342,7 +343,7 @@ namespace butl
     // Flush the buffer.
     //
     size_t wn (bn + an);
-    int r (wn > 0 ? _write (fd_, buf_, wn) : 0);
+    int r (wn > 0 ? _write (fd_.get (), buf_, wn) : 0);
 
     if (r == -1)
       throw_ios_failure (errno);
@@ -378,7 +379,7 @@ namespace butl
 
     // The data tail doesn't fit the buffer so write it to the file.
     //
-    r = _write (fd_, s, n);
+    r = _write (fd_.get (), s, n);
 
     if (r == -1)
       throw_ios_failure (errno);
@@ -393,15 +394,15 @@ namespace butl
     return (m & flag) == flag;
   }
 
-  inline static int
-  mode (int fd, fdstream_mode m)
+  inline static auto_fd
+  mode (auto_fd fd, fdstream_mode m)
   {
-    if (fd != -1 &&
+    if (fd.get () >= 0 &&
         (flag (m, fdstream_mode::text) ||
          flag (m, fdstream_mode::binary) ||
          flag (m, fdstream_mode::blocking) ||
          flag (m, fdstream_mode::non_blocking)))
-      fdmode (fd, m);
+      fdmode (fd.get (), m);
 
     return fd;
   }
@@ -409,8 +410,8 @@ namespace butl
   // fdstream_base
   //
   fdstream_base::
-  fdstream_base (int fd, fdstream_mode m)
-      : fdstream_base (mode (fd, m)) // Delegate.
+  fdstream_base (auto_fd&& fd, fdstream_mode m)
+      : fdstream_base (mode (move (fd), m)) // Delegate.
   {
   }
 
@@ -582,7 +583,7 @@ namespace butl
 
   // Utility functions
   //
-  int
+  auto_fd
   fdopen (const char* f, fdopen_mode m, permissions p)
   {
     mode_t pf (S_IREAD | S_IWRITE | S_IEXEC);
@@ -714,7 +715,7 @@ namespace butl
       }
     }
 
-    return fd;
+    return auto_fd (fd);
   }
 
 #ifndef _WIN32
@@ -793,7 +794,7 @@ namespace butl
   int
   fdnull (bool temp) noexcept
   {
-    // No need to translate /r/n before sending it to void.
+    // No need to translate \r\n before sending it to void.
     //
     if (!temp)
       return _sopen ("nul", _O_RDWR | _O_BINARY, _SH_DENYNO);
diff --git a/butl/fdstream.ixx b/butl/fdstream.ixx
index c7c329b..5d38d36 100644
--- a/butl/fdstream.ixx
+++ b/butl/fdstream.ixx
@@ -6,26 +6,51 @@
 
 namespace butl
 {
-  // ifdstream
+  // auto_fd
   //
-  inline ifdstream::
-  ifdstream ()
-      : std::istream (&buf_)
+  inline auto_fd& auto_fd::
+  operator= (auto_fd&& fd) noexcept
+  {
+    reset (fd.release ());
+    return *this;
+  }
+
+  inline int auto_fd::
+  release () noexcept
   {
-    exceptions (badbit | failbit);
+    int r (fd_);
+    fd_ = -1;
+    return r;
   }
 
+  inline void auto_fd::
+  reset (int fd) noexcept
+  {
+    if (fd_ >= 0)
+      fdclose (fd_); // Don't check for an error as not much we can do here.
+
+    fd_ = fd;
+  }
+
+  // ifdstream
+  //
   inline ifdstream::
-  ifdstream (int fd, iostate e)
-      : fdstream_base (fd), std::istream (&buf_)
+  ifdstream (auto_fd&& fd, iostate e)
+      : fdstream_base (std::move (fd)), std::istream (&buf_)
   {
     assert (e & badbit);
     exceptions (e);
   }
 
   inline ifdstream::
-  ifdstream (int fd, fdstream_mode m, iostate e)
-      : fdstream_base (fd, m),
+  ifdstream (iostate e)
+      : ifdstream (auto_fd (), e) // Delegate.
+  {
+  }
+
+  inline ifdstream::
+  ifdstream (auto_fd&& fd, fdstream_mode m, iostate e)
+      : fdstream_base (std::move (fd), m),
         std::istream (&buf_),
         skip_ ((m & fdstream_mode::skip) == fdstream_mode::skip)
   {
@@ -84,23 +109,22 @@ namespace butl
   // ofdstream
   //
   inline ofdstream::
-  ofdstream ()
-      : std::ostream (&buf_)
+  ofdstream (auto_fd&& fd, iostate e)
+      : fdstream_base (std::move (fd)), std::ostream (&buf_)
   {
-    exceptions (badbit | failbit);
+    assert (e & badbit);
+    exceptions (e);
   }
 
   inline ofdstream::
-  ofdstream (int fd, iostate e)
-      : fdstream_base (fd), std::ostream (&buf_)
+  ofdstream (iostate e)
+      : ofdstream (auto_fd (), e) // Delegate.
   {
-    assert (e & badbit);
-    exceptions (e);
   }
 
   inline ofdstream::
-  ofdstream (int fd, fdstream_mode m, iostate e)
-      : fdstream_base (fd, m), std::ostream (&buf_)
+  ofdstream (auto_fd&& fd, fdstream_mode m, iostate e)
+      : fdstream_base (std::move (fd), m), std::ostream (&buf_)
   {
     assert (e & badbit);
     exceptions (e);
@@ -156,13 +180,13 @@ namespace butl
 
   // fdopen()
   //
-  inline int
+  inline auto_fd
   fdopen (const std::string& f, fdopen_mode m, permissions p)
   {
     return fdopen (f.c_str (), m, p);
   }
 
-  inline int
+  inline auto_fd
   fdopen (const path& f, fdopen_mode m, permissions p)
   {
     return fdopen (f.string (), m, p);
diff --git a/butl/optional b/butl/optional
index 0ae7e7b..21d686c 100644
--- a/butl/optional
+++ b/butl/optional
@@ -11,8 +11,8 @@ namespace butl
 {
   // Simple optional class template while waiting for std::optional.
   //
-  struct nullopt_t {constexpr nullopt_t (int) {}};
-  constexpr const nullopt_t nullopt = 1;
+  struct nullopt_t {constexpr explicit nullopt_t (int) {}};
+  constexpr const nullopt_t nullopt (1);
 
   template <typename T>
   class optional
diff --git a/butl/pager.cxx b/butl/pager.cxx
index b154a5c..a03582c 100644
--- a/butl/pager.cxx
+++ b/butl/pager.cxx
@@ -15,6 +15,7 @@
 #endif
 
 #include <cstring>      // strchr()
+#include <utility>      // move()
 #include <system_error>
 
 #include <butl/fdstream> // fdclose()
@@ -134,13 +135,13 @@ namespace butl
       bool r;
       if (p_.try_wait (r))
       {
-        fdclose (p_.out_fd);
+        p_.out_fd.reset ();
 
         if (pager != nullptr)
           throw system_error (ECHILD, system_category ());
       }
       else
-        os_.open (p_.out_fd);
+        os_.open (move (p_.out_fd));
     }
     catch (const process_error& e)
     {
diff --git a/butl/process b/butl/process
index c69c306..e98e367 100644
--- a/butl/process
+++ b/butl/process
@@ -17,6 +17,7 @@
 #include <butl/path>
 #include <butl/export>
 #include <butl/optional>
+#include <butl/fdstream> // auto_fd
 
 namespace butl
 {
@@ -134,7 +135,7 @@ namespace butl
     // the child process. When reading in the text mode the sequence of 0xD,
     // 0xA characters is translated into the single OxA character and 0x1A is
     // interpreted as EOF. When writing in the text mode the OxA character is
-    // translated into the 0xD, 0xA sequence. Use the _setmode() function to
+    // translated into the 0xD, 0xA sequence. Use the fdmode() function to
     // change the mode, if required.
     //
     // Instead of passing -1, -2 or the default value, you can also pass your
@@ -216,8 +217,6 @@ namespace butl
     // Create an empty or "already terminated" process. By default the
     // termination status is abnormal but you can change that.
     //
-    // @@ Need to audit all calls (__attribute__((deprecated))).
-    //
     explicit
     process (optional<status_type> status = nullopt);
 
@@ -295,9 +294,12 @@ namespace butl
     handle_type handle;
     optional<status_type> status; // Absence means terminated abnormally.
 
-    int out_fd; // Write to this fd to send to the new process' stdin.
-    int in_ofd; // Read from this fd to receive from the new process' stdout.
-    int in_efd; // Read from this fd to receive from the new process' stderr.
+    // Use the following file descriptors to communicate with the new process's
+    // standard streams.
+    //
+    auto_fd out_fd; // Write to it to send to stdin.
+    auto_fd in_ofd; // Read from it to receive from stdout.
+    auto_fd in_efd; // Read from it to receive from stderr.
   };
 }
 
diff --git a/butl/process.cxx b/butl/process.cxx
index 3af42cf..d8b10be 100644
--- a/butl/process.cxx
+++ b/butl/process.cxx
@@ -37,10 +37,11 @@
 #include <cassert>
 #include <cstddef> // size_t
 #include <cstring> // strlen(), strchr()
+#include <utility> // move()
 #include <ostream>
 
 #include <butl/utility>  // casecmp()
-#include <butl/fdstream> // fdnull(), fdclose()
+#include <butl/fdstream> // fdnull()
 
 using namespace std;
 
@@ -50,49 +51,6 @@ using namespace butl::win32;
 
 namespace butl
 {
-  class auto_fd
-  {
-  public:
-    explicit
-    auto_fd (int fd = -1) noexcept: fd_ (fd) {}
-
-    auto_fd (const auto_fd&) = delete;
-    auto_fd& operator= (const auto_fd&) = delete;
-
-    ~auto_fd () noexcept {reset ();}
-
-    int
-    get () const noexcept {return fd_;}
-
-    int
-    release () noexcept
-    {
-      int r (fd_);
-      fd_ = -1;
-      return r;
-    }
-
-    void
-    reset (int fd = -1) noexcept
-    {
-      if (fd_ != -1)
-      {
-        bool r (fdclose (fd_));
-
-        // The valid file descriptor that has no IO operations being
-        // performed on it should close successfully, unless something is
-        // severely damaged.
-        //
-        assert (r);
-      }
-
-      fd_ = fd;
-    }
-
-  private:
-    int fd_;
-  };
-
   static process_path
   path_search (const char*, const dir_path&);
 
@@ -158,6 +116,16 @@ namespace butl
     } while (*p != nullptr);
   }
 
+  process::
+  process (const char* cwd,
+           const process_path& pp, const char* args[],
+           process& in, int out, int err)
+      : process (cwd, pp, args, in.in_ofd.get (), out, err)
+  {
+    assert (in.in_ofd.get () != -1); // Should be a pipe.
+    in.in_ofd.reset (); // Close it on our side.
+  }
+
 #ifndef _WIN32
 
   static process_path
@@ -365,19 +333,9 @@ namespace butl
 
     assert (handle != 0); // Shouldn't get here unless in the parent process.
 
-    this->out_fd = out_fd[1].release ();
-    this->in_ofd = in_ofd[0].release ();
-    this->in_efd = in_efd[0].release ();
-  }
-
-  process::
-  process (const char* cwd,
-           const process_path& pp, const char* args[],
-           process& in, int out, int err)
-      : process (cwd, pp, args, in.in_ofd, out, err)
-  {
-    assert (in.in_ofd != -1); // Should be a pipe.
-    close (in.in_ofd); // Close it on our side.
+    this->out_fd = move (out_fd[1]);
+    this->in_ofd = move (in_ofd[0]);
+    this->in_efd = move (in_efd[0]);
   }
 
   bool process::
@@ -849,13 +807,9 @@ namespace butl
       return fd;
     };
 
-    auto_fd out_fd (in == -1 ? open_osfhandle (out_h[1]) : -1);
-    auto_fd in_ofd (out == -1 ? open_osfhandle (in_oh[0]) : -1);
-    auto_fd in_efd (err == -1 ? open_osfhandle (in_eh[0]) : -1);
-
-    this->out_fd = out_fd.release ();
-    this->in_ofd = in_ofd.release ();
-    this->in_efd = in_efd.release ();
+    this->out_fd.reset (in  == -1 ? open_osfhandle (out_h[1]) : -1);
+    this->in_ofd.reset (out == -1 ? open_osfhandle (in_oh[0]) : -1);
+    this->in_efd.reset (err == -1 ? open_osfhandle (in_eh[0]) : -1);
 
     this->handle = process.release ();
 
@@ -864,16 +818,6 @@ namespace butl
     assert (this->handle != 0 && this->handle != INVALID_HANDLE_VALUE);
   }
 
-  process::
-  process (const char* cwd,
-           const process_path& pp, const char* args[],
-           process& in, int out, int err)
-      : process (cwd, pp, args, in.in_ofd, out, err)
-  {
-    assert (in.in_ofd != -1); // Should be a pipe.
-    _close (in.in_ofd); // Close it on our side.
-  }
-
   bool process::
   wait (bool ie)
   {
diff --git a/butl/process.ixx b/butl/process.ixx
index 6d4dd2f..1bc259c 100644
--- a/butl/process.ixx
+++ b/butl/process.ixx
@@ -139,9 +139,9 @@ namespace butl
   process (process&& p)
       : handle (p.handle),
         status (p.status),
-        out_fd (p.out_fd),
-        in_ofd (p.in_ofd),
-        in_efd (p.in_efd)
+        out_fd (std::move (p.out_fd)),
+        in_ofd (std::move (p.in_ofd)),
+        in_efd (std::move (p.in_efd))
   {
     p.handle = 0;
   }
@@ -156,9 +156,9 @@ namespace butl
 
       handle = p.handle;
       status = std::move (p.status);
-      out_fd = p.out_fd;
-      in_ofd = p.in_ofd;
-      in_efd = p.in_efd;
+      out_fd = std::move (p.out_fd);
+      in_ofd = std::move (p.in_ofd);
+      in_efd = std::move (p.in_efd);
 
       p.handle = 0;
     }
diff --git a/tests/fdstream/driver.cxx b/tests/fdstream/driver.cxx
index f77e2d5..4d72284 100644
--- a/tests/fdstream/driver.cxx
+++ b/tests/fdstream/driver.cxx
@@ -14,6 +14,7 @@
 #include <cassert>
 #include <sstream>
 #include <fstream>
+#include <utility>   // move()
 #include <iostream>
 #include <exception>
 
@@ -134,8 +135,8 @@ main (int argc, const char* argv[])
       cout.flush ();
 
       // @@ MINGW GCC 4.9 doesn't implement this_thread. If ifdstream
-      //    non-blocking read will ever be implemented use Win32 Sleep()
-      //    instead.
+      //    non-blocking read will ever be implemented on Windows use Win32
+      //    Sleep() instead.
       //
 #ifndef _WIN32
       this_thread::sleep_for (chrono::milliseconds (50));
@@ -250,7 +251,7 @@ main (int argc, const char* argv[])
   to_file (f, "", fdopen_mode::truncate);
 
   {
-    ifdstream ifs (-1, ifdstream::badbit);
+    ifdstream ifs (ifdstream::badbit);
     ifs.open (f);
 
     string s;
@@ -258,7 +259,7 @@ main (int argc, const char* argv[])
   }
 
   {
-    ifdstream ifs (-1, fdstream_mode::text, ifdstream::badbit);
+    ifdstream ifs (nullfd, fdstream_mode::text, ifdstream::badbit);
     ifs.open (f);
 
     string s;
@@ -268,7 +269,7 @@ main (int argc, const char* argv[])
   // Check creating unopened ofdstream with a non-default exception mask.
   //
   {
-    ofdstream ofs (-1, ifdstream::badbit);
+    ofdstream ofs (ifdstream::badbit);
     ofs.open (f);
 
     istringstream is;
@@ -277,7 +278,7 @@ main (int argc, const char* argv[])
   }
 
   {
-    ofdstream ofs (-1, fdstream_mode::binary, ifdstream::badbit);
+    ofdstream ofs (nullfd, fdstream_mode::binary, ifdstream::badbit);
     ofs.open (f);
 
     istringstream is;
@@ -406,8 +407,8 @@ main (int argc, const char* argv[])
     const char* args[] = {argv[0], "-c", nullptr};
     process pr (args, -1, -1);
 
-    ofdstream os (pr.out_fd);
-    ifdstream is (pr.in_ofd, fdstream_mode::non_blocking);
+    ofdstream os (move (pr.out_fd));
+    ifdstream is (move (pr.in_ofd), fdstream_mode::non_blocking);
 
     const string s (
       "0123456789\nABCDEFGHIJKLMNOPQRSTUVWXYZ\nabcdefghijklmnopqrstuvwxyz");
diff --git a/tests/process/driver.cxx b/tests/process/driver.cxx
index d59b1a7..bc75cc2 100644
--- a/tests/process/driver.cxx
+++ b/tests/process/driver.cxx
@@ -65,15 +65,15 @@ exec (const path& p,
         bool s;
         r = !pr.try_wait (s); // Couldn't exit as waiting for the input.
 
-        auto bin_mode = [bin](int fd) -> int
-          {
-            if (bin)
-              fdmode (fd, fdstream_mode::binary);
+        auto bin_mode = [bin](auto_fd fd) -> auto_fd
+        {
+          if (bin)
+            fdmode (fd.get (), fdstream_mode::binary);
 
-            return fd;
-          };
+          return fd;
+        };
 
-        ofdstream os (bin_mode (pr.out_fd));
+        ofdstream os (bin_mode (move (pr.out_fd)));
         copy (in.begin (), in.end (), ostream_iterator<char> (os));
         os.close ();
 
@@ -89,12 +89,11 @@ exec (const path& p,
             // overall pipeline looks like 'os -> pr -> pr2 -> pr3 -> is'.
             //
             process pr3 (cwd, args.data (), -1, -1, -2);
-            process pr2 (cwd, args.data (), pr, bin_mode (pr3.out_fd), -2);
 
-            bool cr (fdclose (pr3.out_fd));
-            assert (cr);
+            process pr2 (
+              cwd, args.data (), pr, bin_mode (move (pr3.out_fd)).get (), -2);
 
-            ifdstream is (bin_mode (pr3.in_ofd));
+            ifdstream is (bin_mode (move (pr3.in_ofd)));
 
             o = vector<char> (
               (istreambuf_iterator<char> (is)), istreambuf_iterator<char> ());
@@ -104,7 +103,7 @@ exec (const path& p,
           }
           else
           {
-            ifdstream is (bin_mode (pr.in_ofd));
+            ifdstream is (bin_mode (move (pr.in_ofd)));
 
             o = vector<char> (
               (istreambuf_iterator<char> (is)), istreambuf_iterator<char> ());
@@ -125,7 +124,7 @@ exec (const path& p,
 
         if (err && !out)
         {
-          ifdstream is (bin_mode (pr.in_efd));
+          ifdstream is (bin_mode (move (pr.in_efd)));
 
           vector<char> e
             ((istreambuf_iterator<char> (is)), istreambuf_iterator<char> ());