linux/arch/um/drivers/xterm_kern.c

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/*
* Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include "linux/errno.h"
#include "linux/slab.h"
#include "linux/signal.h"
#include "linux/interrupt.h"
#include "asm/irq.h"
#include "irq_user.h"
#include "irq_kern.h"
#include "kern_util.h"
#include "os.h"
#include "xterm.h"
struct xterm_wait {
struct completion ready;
int fd;
int pid;
int new_fd;
};
static irqreturn_t xterm_interrupt(int irq, void *data)
{
struct xterm_wait *xterm = data;
int fd;
fd = os_rcv_fd(xterm->fd, &xterm->pid);
if(fd == -EAGAIN)
return(IRQ_NONE);
xterm->new_fd = fd;
complete(&xterm->ready);
return(IRQ_HANDLED);
}
int xterm_fd(int socket, int *pid_out)
{
struct xterm_wait *data;
int err, ret;
data = kmalloc(sizeof(*data), GFP_KERNEL);
if(data == NULL){
printk(KERN_ERR "xterm_fd : failed to allocate xterm_wait\n");
return(-ENOMEM);
}
/* This is a locked semaphore... */
*data = ((struct xterm_wait)
{ .fd = socket,
.pid = -1,
.new_fd = -1 });
init_completion(&data->ready);
err = um_request_irq(XTERM_IRQ, socket, IRQ_READ, xterm_interrupt,
IRQF_DISABLED | IRQF_SHARED | IRQF_SAMPLE_RANDOM,
"xterm", data);
if (err){
printk(KERN_ERR "xterm_fd : failed to get IRQ for xterm, "
"err = %d\n", err);
ret = err;
goto out;
}
/* ... so here we wait for an xterm interrupt.
*
* XXX Note, if the xterm doesn't work for some reason (eg. DISPLAY
* isn't set) this will hang... */
wait_for_completion(&data->ready);
free_irq(XTERM_IRQ, data);
ret = data->new_fd;
*pid_out = data->pid;
out:
kfree(data);
return(ret);
}
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/