slirp_user.c

Go to the documentation of this file.

/*
 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL.
 */

#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/wait.h>
#include <net_user.h>
#include <os.h>
#include "slirp.h"

static int slirp_user_init(void *data, void *dev)
{
    struct slirp_data *pri = data;

    pri->dev = dev;
    return 0;
}

struct slirp_pre_exec_data {
    int stdin;
    int stdout;
};

static void slirp_pre_exec(void *arg)
{
    struct slirp_pre_exec_data *data = arg;

    if (data->stdin != -1)
        dup2(data->stdin, 0);
    if (data->stdout != -1)
        dup2(data->stdout, 1);
}

static int slirp_tramp(char **argv, int fd)
{
    struct slirp_pre_exec_data pe_data;
    int pid;

    pe_data.stdin = fd;
    pe_data.stdout = fd;
    pid = run_helper(slirp_pre_exec, &pe_data, argv);

    return pid;
}

static int slirp_open(void *data)
{
    struct slirp_data *pri = data;
    int fds[2], pid, err;

    err = os_pipe(fds, 1, 1);
    if (err)
        return err;

    err = slirp_tramp(pri->argw.argv, fds[1]);
    if (err < 0) {
        printk(UM_KERN_ERR "slirp_tramp failed - errno = %d\n", -err);
        goto out;
    }
    pid = err;

    pri->slave = fds[1];
    pri->slip.pos = 0;
    pri->slip.esc = 0;
    pri->pid = err;

    return fds[0];
out:
    close(fds[0]);
    close(fds[1]);
    return err;
}

static void slirp_close(int fd, void *data)
{
    struct slirp_data *pri = data;
    int err;

    close(fd);
    close(pri->slave);

    pri->slave = -1;

    if (pri->pid<1) {
        printk(UM_KERN_ERR "slirp_close: no child process to shut "
               "down\n");
        return;
    }

#if 0
    if (kill(pri->pid, SIGHUP)<0) {
        printk(UM_KERN_ERR "slirp_close: sending hangup to %d failed "
               "(%d)\n", pri->pid, errno);
    }
#endif
    err = helper_wait(pri->pid);
    if (err < 0)
        return;

    pri->pid = -1;
}

int slirp_user_read(int fd, void *buf, int len, struct slirp_data *pri)
{
    return slip_proto_read(fd, buf, len, &pri->slip);
}

int slirp_user_write(int fd, void *buf, int len, struct slirp_data *pri)
{
    return slip_proto_write(fd, buf, len, &pri->slip);
}

const struct net_user_info slirp_user_info = {
    .init       = slirp_user_init,
    .open       = slirp_open,
    .close      = slirp_close,
    .remove     = NULL,
    .add_address    = NULL,
    .delete_address = NULL,
    .mtu        = BUF_SIZE,
    .max_packet = BUF_SIZE,
};