~drizzle-trunk/drizzle/development

/* Copyright (C) 2000 MySQL AB

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program; if not, write to the Free Software

   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/*

  Note that we can't have assertion on file descriptors;  The reason for

  this is that during mysql shutdown, another thread can close a file

  we are working on.  In this case we should just return read errors from

  the file descriptior.

*/

#include "vio_priv.h"

int vio_errno(Vio *vio __attribute__((unused)))

{

  return socket_errno;		/* On Win32 this mapped to WSAGetLastError() */

}

size_t vio_read(Vio * vio, uchar* buf, size_t size)

{

  size_t r;

  /* Ensure nobody uses vio_read_buff and vio_read simultaneously */

  assert(vio->read_end == vio->read_pos);

  r= read(vio->sd, buf, size);

  return r;

}

/*

  Buffered read: if average read size is small it may

  reduce number of syscalls.

*/

size_t vio_read_buff(Vio *vio, uchar* buf, size_t size)

{

  size_t rc;

#define VIO_UNBUFFERED_READ_MIN_SIZE 2048

  if (vio->read_pos < vio->read_end)

  {

    rc= min((size_t) (vio->read_end - vio->read_pos), size);

    memcpy(buf, vio->read_pos, rc);

    vio->read_pos+= rc;

    /*

      Do not try to read from the socket now even if rc < size:

      vio_read can return -1 due to an error or non-blocking mode, and

      the safest way to handle it is to move to a separate branch.

    */

  }

  else if (size < VIO_UNBUFFERED_READ_MIN_SIZE)

  {

    rc= vio_read(vio, (uchar*) vio->read_buffer, VIO_READ_BUFFER_SIZE);

    if (rc != 0 && rc != (size_t) -1)

    {

      if (rc > size)

      {

        vio->read_pos= vio->read_buffer + size;

        vio->read_end= vio->read_buffer + rc;

        rc= size;

      }

      memcpy(buf, vio->read_buffer, rc);

    }

  }

  else

    rc= vio_read(vio, buf, size);

  return rc;

#undef VIO_UNBUFFERED_READ_MIN_SIZE

}

size_t vio_write(Vio * vio, const uchar* buf, size_t size)

{

  size_t r;

  r = write(vio->sd, buf, size);

  return r;

}

int vio_blocking(Vio * vio, bool set_blocking_mode, bool *old_mode)

{

  int r=0;

  *old_mode= test(!(vio->fcntl_mode & O_NONBLOCK));

  if (vio->sd >= 0)

  {

    int old_fcntl=vio->fcntl_mode;

    if (set_blocking_mode)

      vio->fcntl_mode &= ~O_NONBLOCK; /* clear bit */

    else

      vio->fcntl_mode |= O_NONBLOCK; /* set bit */

    if (old_fcntl != vio->fcntl_mode)

    {

      r= fcntl(vio->sd, F_SETFL, vio->fcntl_mode);

      if (r == -1)

      {

        vio->fcntl_mode= old_fcntl;

      }

    }

  }

  return r;

}

bool

vio_is_blocking(Vio * vio)

{

  bool r;

  r = !(vio->fcntl_mode & O_NONBLOCK);

  return r;

}

int vio_fastsend(Vio * vio __attribute__((unused)))

{

  int nodelay = 1;

  int r;

  r= setsockopt(vio->sd, IPPROTO_TCP, TCP_NODELAY,

                &nodelay, sizeof(nodelay));

  assert(r == 0);

  return r;

}

int32_t vio_keepalive(Vio* vio, bool set_keep_alive)

{

  int r= 0;

  uint32_t opt= 0;

  if (set_keep_alive)

    opt= 1;

  r= setsockopt(vio->sd, SOL_SOCKET, SO_KEEPALIVE, (char *) &opt, sizeof(opt));

  return r;

}

bool

vio_should_retry(Vio * vio __attribute__((unused)))

{

  int en = socket_errno;

  return (en == SOCKET_EAGAIN || en == SOCKET_EINTR ||

	  en == SOCKET_EWOULDBLOCK);

}

bool

vio_was_interrupted(Vio *vio __attribute__((unused)))

{

  int en= socket_errno;

  return (en == SOCKET_EAGAIN || en == SOCKET_EINTR ||

	  en == SOCKET_EWOULDBLOCK || en == SOCKET_ETIMEDOUT);

}

int vio_close(Vio * vio)

{

  int r=0;

 if (vio->type != VIO_CLOSED)

  {

    assert(vio->sd >= 0);

    if (shutdown(vio->sd, SHUT_RDWR))

      r= -1;

    if (closesocket(vio->sd))

      r= -1;

  }

  vio->type= VIO_CLOSED;

  vio->sd=   -1;

  return r;

}

const char *vio_description(Vio * vio)

{

  return vio->desc;

}

enum enum_vio_type vio_type(Vio* vio)

{

  return vio->type;

}

my_socket vio_fd(Vio* vio)

{

  return vio->sd;

}

bool vio_peer_addr(Vio *vio, char *buf, uint16_t *port, size_t buflen)

{

  int error;

  char port_buf[NI_MAXSERV];

  socklen_t addrLen = sizeof(vio->remote);

  if (getpeername(vio->sd, (struct sockaddr *) (&vio->remote),

                  &addrLen) != 0)

  {

    return true;

  }

  vio->addrLen= (int)addrLen;

  if ((error= getnameinfo((struct sockaddr *)(&vio->remote), 

                          addrLen,

                          buf, buflen,

                          port_buf, NI_MAXSERV, NI_NUMERICHOST|NI_NUMERICSERV)))

  {

    return true;

  }

  *port= (uint16_t)strtol(port_buf, (char **)NULL, 10);

  return false;

}

/* Return 0 if there is data to be read */

bool vio_poll_read(Vio *vio,uint timeout)

{

  struct pollfd fds;

  int res;

  fds.fd=vio->sd;

  fds.events=POLLIN;

  fds.revents=0;

  if ((res=poll(&fds,1,(int) timeout*1000)) <= 0)

  {

    return res < 0 ? false : true;		/* Don't return 1 on errors */

  }

  return (fds.revents & (POLLIN | POLLERR | POLLHUP) ? false : true);

}

bool vio_peek_read(Vio *vio, uint32_t *bytes)

{

  char buf[1024];

  ssize_t res= recv(vio->sd, &buf, sizeof(buf), MSG_PEEK);

  if (res < 0)

    return true;

  *bytes= (uint32_t)res;

  return false;

}

void vio_timeout(Vio *vio, uint which, uint timeout)

{

  int r;

  /* POSIX specifies time as struct timeval. */

  struct timeval wait_timeout;

  wait_timeout.tv_sec= timeout;

  wait_timeout.tv_usec= 0;

  r= setsockopt(vio->sd, SOL_SOCKET, which ? SO_SNDTIMEO : SO_RCVTIMEO,

                IF_WIN(const char*, const void*)&wait_timeout,

                sizeof(wait_timeout));

  assert(r == 0);

}