vcon_stream_impl.h

/*
 * (c) 2010 Alexander Warg <warg@os.inf.tu-dresden.de>
 *     economic rights: Technische Universität Dresden (Germany)
 *
 * License: see LICENSE.spdx (in this directory or the directories above)
 */
 
#include <l4/re/env>
#include <l4/sys/factory>
#include <l4/cxx/minmax>
 
#include "vcon_stream.h"
 
#include <termios.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/ttydefaults.h>
 
namespace L4Re { namespace Core {
Vcon_stream::Vcon_stream(L4::Cap<L4::Vcon> s) noexcept
: Be_file_stream(),
  _s(s), _irq(L4Re::virt_cap_alloc->alloc<L4::Semaphore>()), _irq_bound(false)
{
  // [[maybe_unused]] int res =
  l4_error(L4Re::Env::env()->factory()->create(_irq));
  // (void)res; // handle errors!
}
 
ssize_t
Vcon_stream::readv(const struct iovec *iovec, int iovcnt) noexcept
{
  if (iovcnt < 0)
    return -EINVAL;
 
  if (!_irq_bound)
    {
      bool was_bound = __atomic_exchange_n(&_irq_bound, true, __ATOMIC_SEQ_CST);
      if (!was_bound)
        if (l4_error(_s->bind(0, _irq)) < 0)
          return -EIO;
    }
 
  ssize_t bytes = 0;
  for (; iovcnt > 0; --iovcnt, ++iovec)
    {
      size_t len = cxx::min<size_t>(iovec->iov_len, SSIZE_MAX - bytes);
      if (len == 0)
        continue;
 
      char *buf = static_cast<char *>(iovec->iov_base);
 
      while (1)
        {
          size_t l = cxx::min<size_t>(L4_VCON_READ_SIZE, len);
          int ret = _s->read(buf, l);
 
          if (ret > static_cast<int>(l))
            ret = l;
 
          if (ret < 0)
            return ret;
          else if (ret == 0)
            {
              if (bytes)
                return bytes;
 
              ret = _s->read(buf, l);
              if (ret < 0)
                return ret;
              else if (ret == 0)
                {
                  _irq->down();
                  continue;
                }
            }
 
          bytes += ret;
          len   -= ret;
          buf   += ret;
 
          if (len == 0)
            break;
        }
    }
 
  return bytes;
}
 
ssize_t
Vcon_stream::writev(const struct iovec *iovec, int iovcnt) noexcept
{
  l4_msg_regs_t store;
  l4_msg_regs_t *mr = l4_utcb_mr();
 
  if (iovcnt < 0)
    return -EINVAL;
 
  Vfs_config::memcpy(&store, mr, sizeof(store));
 
  ssize_t written = 0;
  while (iovcnt)
    {
      size_t sl = cxx::min<size_t>(iovec->iov_len, SSIZE_MAX - written);
      char const *b = static_cast<char const *>(iovec->iov_base);
 
      for (; sl > L4_VCON_WRITE_SIZE
           ; sl -= L4_VCON_WRITE_SIZE, b += L4_VCON_WRITE_SIZE,
             written += L4_VCON_WRITE_SIZE)
        _s->send(b, L4_VCON_WRITE_SIZE);
 
      _s->send(b, sl);
 
      written += sl;
 
      ++iovec;
      --iovcnt;
    }
  Vfs_config::memcpy(mr, &store, sizeof(store));
  return written;
}
 
int
Vcon_stream::fstat64(struct stat64 *buf) const noexcept
{
  buf->st_size = 0;
  buf->st_mode = 0666;
  buf->st_dev = _s.cap();
  buf->st_ino = 0;
  return 0;
}
 
int
Vcon_stream::ioctl(unsigned long request, va_list args) noexcept
{
  switch (request) {
    case TCGETS:
        {
          //vt100_tcgetattr(term, (struct termios *)argp);
 
          struct termios *t = va_arg(args, struct termios *);
 
          l4_vcon_attr_t l4a;
          if (!l4_error(_s->get_attr(&l4a)))
            {
              t->c_iflag = l4a.i_flags;
              t->c_oflag = l4a.o_flags; // output flags
              t->c_cflag = 0; // control flags
              t->c_lflag = l4a.l_flags; // local flags
            }
          else
            t->c_iflag = t->c_oflag = t->c_cflag = t->c_lflag = 0;
#if 0
          //t->c_lflag |= ECHO; // if term->echo
          t->c_lflag |= ICANON; // if term->term_mode == VT100MODE_COOKED
#endif
 
          t->c_cc[VEOF]     = CEOF;
          t->c_cc[VEOL]     = _POSIX_VDISABLE;
          t->c_cc[VEOL2]    = _POSIX_VDISABLE;
          t->c_cc[VERASE]   = CERASE;
          t->c_cc[VWERASE]  = CWERASE;
          t->c_cc[VKILL]    = CKILL;
          t->c_cc[VREPRINT] = CREPRINT;
          t->c_cc[VINTR]    = CINTR;
          t->c_cc[VQUIT]    = _POSIX_VDISABLE;
          t->c_cc[VSUSP]    = CSUSP;
          t->c_cc[VSTART]   = CSTART;
          t->c_cc[VSTOP]    = CSTOP;
          t->c_cc[VLNEXT]   = CLNEXT;
          t->c_cc[VDISCARD] = CDISCARD;
          t->c_cc[VMIN]     = CMIN;
          t->c_cc[VTIME]    = 0;
 
        }
 
      return 0;
 
    case TCSETS:
    case TCSETSW:
    case TCSETSF:
        {
          //vt100_tcsetattr(term, (struct termios *)argp);
          struct termios const *t = va_arg(args, struct termios const *);
 
          // XXX: well, we're cheating, get this from the other side!
 
          l4_vcon_attr_t l4a;
          l4a.i_flags = t->c_iflag;
          l4a.o_flags = t->c_oflag; // output flags
          l4a.l_flags = t->c_lflag; // local flags
          _s->set_attr(&l4a);
        }
      return 0;
 
    default:
      break;
  };
  return -ENOTTY;
}
 
}}