cmd/prstat/prfile.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 1999 by Sun Microsystems, Inc.
 * All rights reserved.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <strings.h>

#include "prtable.h"
#include "prutil.h"
#include "prfile.h"

#define FDS_TABLE_SIZE  1024

static fd_t *fd_tbl = NULL;
static int fd_max;
static int fd_cnt;
static int fd_cnt_cur;
static int fd_cnt_old;
static fds_t *fds_tbl[FDS_TABLE_SIZE];

void
fd_init(int n)
{
    fd_max = n;
    fd_cnt = fd_cnt_cur = fd_cnt_old = 0;
    fd_tbl = Zalloc(sizeof (fd_t) * n);
    (void) memset(fds_tbl, 0, sizeof (fds_t *) * FDS_TABLE_SIZE);
}

void
fd_exit()
{
    if (fd_tbl)
        free(fd_tbl);
}

void
fd_close(fd_t *fdp)
{
    if (fdp) {
        if (fdp->fd_fd >= 0 && fdp->fd_name[0] != '\0') {
            (void) close(fdp->fd_fd);
            fd_cnt--;
        }

        (void) memset(fdp, 0, sizeof (fd_t));
        fdp->fd_fd = -1;
    }
}

void
fd_closeall()
{
    fd_t *fdp = fd_tbl;
    int i;

    for (i = 0; i < fd_max; i++) {
        fd_close(fdp);
        fdp++;
    }
}

static void
fd_recycle()
{
    fd_t *fdp = fd_tbl;
    int counter;
    int i;

    counter = abs(fd_cnt_old - fd_cnt) + NUM_RESERVED_FD;

    for (i = 0; i < fd_max; i++, fdp++) {

        if (fdp->fd_fd == -1)
            continue;   /* skip recycled ones */

        if (fdp->fd_name[0] != '\0') {  /* file has name */
            (void) close(fdp->fd_fd);
            fd_cnt--;
            counter--;
            fdp->fd_fd = -1;
        }

        if (counter == 0)
            break;
    }
}

fd_t *
fd_open(char *name, int flags, fd_t *fdp)
{
    fd_t *fdp_new;
    int fd;

    if (fd_cnt > fd_max - NUM_RESERVED_FD)
        fd_recycle();

    if (fdp != NULL) {
        if ((strcmp(fdp->fd_name, name) == 0) && (fdp->fd_fd >= 0)) {
            fd_cnt_cur++;
            return (fdp);
        }
    }

again:  fd = open(name, flags);

    if (fd == -1) {
        if ((errno == EMFILE) || (errno == ENFILE)) {
            fd_recycle();
            goto again;
        }
        fdp_new = NULL;
    } else {
        fdp_new = &fd_tbl[fd];
        fdp_new->fd_fd = fd;
        fdp_new->fd_flags = flags;
        (void) strcpy(fdp_new->fd_name, name);
        fd_cnt++;
        fd_cnt_cur++;
    }
    return (fdp_new);
}

int
fd_getfd(fd_t *fdp)
{
    return (fdp->fd_fd);
}

void
fd_update()
{
    fd_cnt_old = fd_cnt_cur;
    fd_cnt_cur = 0;
}

fds_t *
fds_get(pid_t pid)
{
    fds_t *fdsp;
    int hash = pid % FDS_TABLE_SIZE;

    for (fdsp = fds_tbl[hash]; fdsp; fdsp = fdsp->fds_next)
        if (fdsp->fds_pid == pid)   /* searching for pid */
            return (fdsp);

    fdsp = Zalloc(sizeof (fds_t));  /* adding new if pid was not found */
    fdsp->fds_pid = pid;
    fdsp->fds_next = fds_tbl[hash];
    fds_tbl[hash] = fdsp;
    return (fdsp);
}

void
fds_rm(pid_t pid)
{
    fds_t *fds;
    fds_t *fds_prev = NULL;
    int hash = pid % FDS_TABLE_SIZE;

    for (fds = fds_tbl[hash]; fds && fds->fds_pid != pid;
        fds = fds->fds_next)    /* finding pid */
        fds_prev = fds;

    if (fds) {          /* if pid was found */

        fd_close(fds->fds_psinfo);
        fd_close(fds->fds_usage);
        fd_close(fds->fds_lpsinfo);
        fd_close(fds->fds_lusage);

        if (fds_prev)
            fds_prev->fds_next = fds->fds_next;
        else
            fds_tbl[hash] = fds->fds_next;

        free(fds);
    }
}