arch/um/drivers/stdio_console_user.c

#include <stdio.h>
#include <unistd.h>
#include <signal.h>
#include <sched.h>
#include <errno.h>
#include <termios.h>
#include <fcntl.h>
#include <sys/select.h>
#include <sys/time.h>
#include "stdio_console.h"
#include "user_util.h"
#include "kern_util.h"
#include "user.h"

void stdio_write(int fd, const char *string, int len)
{
  static int need_cr = 0;
  int i;

  for(i=0;i<len;i++){
    if(*string == '\n') need_cr = 1;
    else if(need_cr){
      if(*string != '\r') write(fd, "\r", 1);
      need_cr = 0;
    }
    write(fd, string++, 1);
  }
}

void stdio_rcv_proc(int fd)
{
  int n;
  char ch;

  while((n = read(fd, &ch, sizeof(ch))) == sizeof(ch)){
    stdio_receive_char(fd, ch);
  }
  if((n < 0) && (errno != EAGAIN))
    printk("stdio_rcv_proc read failed, errno = %d\n", errno);
  enable_fd(fd);
}

void setup_fd(int fd)
{
  struct termios tt;
  unsigned long flags;

  flags = fcntl(fd, F_GETFL);
  flags |= O_NONBLOCK;
  flags &= ~O_ASYNC;
  if(fcntl(fd, F_SETFL, flags) < 0){
    perror("fcntl setting flags");
    return;
  }  
  tcgetattr(fd, &tt);
  cfmakeraw(&tt);
  if(tcsetattr(fd, TCSADRAIN, &tt) < 0){
    printk("tcsetattr failed, errno = %d\n", errno);
    panic("stdio receive thread couldn't set fd raw");
  }
}

struct xterm_info {
  char tty[2];
  int fd;
  int console_num;
  int *pid_out;
};

static void xterm_tramp(void *arg)
{
  struct xterm_info *info;
  int pid;
  char title[sizeof("Virtual Console nn\0")], flag[sizeof("Sxxnn\0")];

  info = arg;
  sprintf(flag, "-S%c%c%d", info->tty[0], info->tty[1], info->fd);
  sprintf(title, "Virtual Console %d", info->console_num);
  if((pid = fork()) != 0) *info->pid_out = pid;
  else {
    execlp("xterm", "xterm", flag, "-T", title, NULL);
    exit(1);
  }
}

int open_vt(int n, int *pid_out)
{
  struct xterm_info info;
  int master, slave;
  char dev[] = "/dev/ptyXX", c;

  master = getmaster(dev);
  dev[strlen("/dev/")] = 't';
  slave = open(dev, O_RDWR);
  if(slave != -1){
    info.tty[0] = dev[strlen("/dev/pty")];
    info.tty[1] = dev[strlen("/dev/ptyX")];
    info.fd = master;
    info.console_num = n;
    info.pid_out = pid_out;
    input_cb(xterm_tramp, &info, sizeof(info));
    while((read(slave, &c, sizeof(c)) == sizeof(c)) && (c != '\n')) ;
  }
  setup_fd(slave);
  return(slave);
}