/Users/mourrain/Devel/mmx/basix/src/posix_port.cpp

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/******************************************************************************
* MODULE     : posix_port.cpp
* DESCRIPTION: Ports from file descriptors
* COPYRIGHT  : (C) 2010  Joris van der Hoeven
*******************************************************************************
* This software falls under the GNU general public license and comes WITHOUT
* ANY WARRANTY WHATSOEVER. See the file $TEXMACS_PATH/LICENSE for more details.
* If you don't have this file, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
******************************************************************************/

#include <basix/posix_port.hpp>
#include <sys/types.h>
#include <sys/select.h>
#include <sys/wait.h>
#include <unistd.h>


namespace mmx {

/******************************************************************************
* Constructor and destructor
******************************************************************************/

extern table<int,int> out_count;
extern table<int,int> in_count;

posix_port_rep::posix_port_rep (int kind2, int fd2):
  kind (kind2), fd (fd2),
  buffer (""), pos (0), alive (true)
{
  if ((kind & 1) != 0) out_count[fd]= out_count[fd] + 1;
  if ((kind & 2) != 0) in_count [fd]= in_count [fd] + 1;
}

posix_port_rep::~posix_port_rep () {
  if ((kind & 1) != 0) {
    out_count[fd]= out_count[fd] - 1;
    if (out_count[fd] == 0) reset (out_count, fd);
  }
  if ((kind & 2) != 0) {
    in_count [fd]= in_count [fd] - 1;
    if (in_count[fd] == 0) reset (in_count, fd);
  }
}

/******************************************************************************
* Default reimplementations of virtual routines
******************************************************************************/

void
posix_port_rep::send (const char* s, nat n) {
  if (alive) {
    int err= ::write (fd, s, n);
    (void) err;
  }
}

void
posix_port_rep::feed () {
  while (alive && wait (0)) {
    int r;
    char tempout[1024];
    r = ::read (fd, tempout, 1024);
    if (r == -1) {
      ::wait (NULL);
      ERROR ("read failed");
    }
    else if (r == 0) alive= false;
    else buffer << string (tempout, r);
  }
}

bool
posix_port_rep::wait (int msecs) {
  //mmout << "Wait " << msecs << " ms on " << expression () << "\n";
  if ((kind & 2) == 0 || !alive) return false;
  fd_set in_fds;
  FD_ZERO (&in_fds);
  FD_SET (fd, &in_fds);
  
  nat nr;
  struct timeval tv;
  tv.tv_sec  = msecs / 1000;
  tv.tv_usec = 1000 * (msecs % 1000);
  if (msecs < 0) nr= select (fd + 1, &in_fds, NULL, NULL, NULL);
  else nr= select (fd + 1, &in_fds, NULL, NULL, &tv);
  //mmout << "Received " << nr << " on " << fd << "\n";
  return nr > 0;
}

/******************************************************************************
* Global select
******************************************************************************/

nat
wait_port_event (int msecs) {
  //mmout << "Global wait " << msecs << " ms\n";
  int max_fd= 0;

  fd_set in_fds;
  FD_ZERO (&in_fds);
  for (iterator<int> it= entries (in_count); busy (it); ++it) {
    //mmout << "  Setting " << (*it) << "\n";
    FD_SET (*it, &in_fds);
    max_fd= max (max_fd, (*it) + 1);
  }
  
  nat nr;
  struct timeval tv;
  tv.tv_sec  = msecs / 1000;
  tv.tv_usec = 1000 * (msecs % 1000);
  if (msecs < 0) nr= select (max_fd, &in_fds, NULL, NULL, NULL);
  else nr= select (max_fd, &in_fds, NULL, NULL, &tv);
  //mmout << "Received " << nr << "\n";
  return nr;
}

} // namespace mmx