dgrp_ports_ops.c

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/*
 *
 * Copyright 1999-2000 Digi International (www.digi.com)
 *     James Puzzo <jamesp at digi dot com>
 *
 * 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; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

/*
 *
 *  Filename:
 *
 *     dgrp_ports_ops.c
 *
 *  Description:
 *
 *     Handle the file operations required for the /proc/dgrp/ports/...
 *     devices.  Basically gathers tty status for the node and returns it.
 *
 *  Author:
 *
 *     James A. Puzzo
 *
 */

#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/tty.h>
#include <linux/sched.h>
#include <linux/seq_file.h>

#include "dgrp_common.h"

/* File operation declarations */
static int dgrp_ports_open(struct inode *, struct file *);

static const struct file_operations ports_ops = {
    .owner   = THIS_MODULE,
    .open    = dgrp_ports_open,
    .read    = seq_read,
    .llseek  = seq_lseek,
    .release = seq_release
};

static struct inode_operations ports_inode_ops = {
    .permission = dgrp_inode_permission
};


void dgrp_register_ports_hook(struct proc_dir_entry *de)
{
    struct nd_struct *node = de->data;

    de->proc_iops = &ports_inode_ops;
    de->proc_fops = &ports_ops;
    node->nd_ports_de = de;
}

static void *dgrp_ports_seq_start(struct seq_file *seq, loff_t *pos)
{
    if (*pos == 0)
        seq_puts(seq, "#num tty_open pr_open tot_wait MSTAT  IFLAG  OFLAG  CFLAG  BPS    DIGIFLAGS\n");

    return pos;
}

static void *dgrp_ports_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
    struct nd_struct *nd = seq->private;

    if (*pos >= nd->nd_chan_count)
        return NULL;

    *pos += 1;

    return pos;
}

static void dgrp_ports_seq_stop(struct seq_file *seq, void *v)
{
}

static int dgrp_ports_seq_show(struct seq_file *seq, void *v)
{
    loff_t *pos = v;
    struct nd_struct *nd;
    struct ch_struct *ch;
    struct un_struct *tun, *pun;
    unsigned int totcnt;

    nd = seq->private;
    if (!nd)
        return 0;

    if (*pos >= nd->nd_chan_count)
        return 0;

    ch = &nd->nd_chan[*pos];
    tun = &ch->ch_tun;
    pun = &ch->ch_pun;

    /*
     * If port is not open and no one is waiting to
     * open it, the modem signal values can't be
     * trusted, and will be zeroed.
     */
    totcnt = tun->un_open_count +
        pun->un_open_count +
        ch->ch_wait_count[0] +
        ch->ch_wait_count[1] +
        ch->ch_wait_count[2];

    seq_printf(seq, "%02d      %02d      %02d      %02d     0x%04X 0x%04X 0x%04X 0x%04X %-6d 0x%04X\n",
           (int) *pos,
           tun->un_open_count,
           pun->un_open_count,
           ch->ch_wait_count[0] +
           ch->ch_wait_count[1] +
           ch->ch_wait_count[2],
           (totcnt ? ch->ch_s_mlast : 0),
           ch->ch_s_iflag,
           ch->ch_s_oflag,
           ch->ch_s_cflag,
           (ch->ch_s_brate ? (1843200 / ch->ch_s_brate) : 0),
           ch->ch_digi.digi_flags);

    return 0;
}

static const struct seq_operations ports_seq_ops = {
    .start = dgrp_ports_seq_start,
    .next  = dgrp_ports_seq_next,
    .stop  = dgrp_ports_seq_stop,
    .show  = dgrp_ports_seq_show,
};

static int dgrp_ports_open(struct inode *inode, struct file *file)
{
    struct seq_file *seq;
    int rtn;

    rtn = seq_open(file, &ports_seq_ops);
    if (!rtn) {
        seq = file->private_data;
        seq->private = PDE(inode)->data;
    }

    return rtn;
}