ptools/pwait/pwait.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

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

#include <stdio.h>
#include <stdio_ext.h>
#include <ctype.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <dirent.h>
#include <errno.h>
#include <sys/types.h>
#include <stropts.h>
#include <poll.h>
#include <procfs.h>
#include <sys/resource.h>

static int count_my_files();
static char *command;

/* slop to account for extra file descriptors opened by libraries we call */
#define SLOP    5

int
main(int argc, char **argv)
{
    unsigned long remain = 0;
    struct pollfd *pollfd;
    struct pollfd *pfd;
    struct rlimit rlim;
    char *arg;
    unsigned i;
    int verbose = 0;

    if ((command = strrchr(argv[0], '/')) != NULL)
        command++;
    else
        command = argv[0];

    argc--;
    argv++;

    if (argc > 0 && strcmp(argv[0], "-v") == 0) {
        verbose = 1;
        argc--;
        argv++;
    }

    if (argc <= 0) {
        (void) fprintf(stderr, "usage:\t%s [-v] pid ...\n", command);
        (void) fprintf(stderr, "  (wait for processes to terminate)\n");
        (void) fprintf(stderr,
            "  -v: verbose; report terminations to standard out\n");
        return (2);
    }

    /* make sure we have enough file descriptors */
    if (getrlimit(RLIMIT_NOFILE, &rlim) == 0) {
        int nfiles = count_my_files();

        if (rlim.rlim_cur < argc + nfiles + SLOP) {
            rlim.rlim_cur = argc + nfiles + SLOP;
            if (setrlimit(RLIMIT_NOFILE, &rlim) != 0) {
                (void) fprintf(stderr,
                    "%s: insufficient file descriptors\n",
                    command);
                return (2);
            }
        }
        (void) enable_extended_FILE_stdio(-1, -1);
    }

    pollfd = (struct pollfd *)malloc(argc*sizeof (struct pollfd));
    if (pollfd == NULL) {
        perror("malloc");
        return (2);
    }

    for (i = 0; i < argc; i++) {
        char psinfofile[100];

        arg = argv[i];
        if (strchr(arg, '/') != NULL)
            (void) strncpy(psinfofile, arg, sizeof (psinfofile));
        else {
            (void) strcpy(psinfofile, "/proc/");
            (void) strncat(psinfofile, arg, sizeof (psinfofile)-6);
        }
        (void) strncat(psinfofile, "/psinfo",
            sizeof (psinfofile)-strlen(psinfofile));

        pfd = &pollfd[i];
        if ((pfd->fd = open(psinfofile, O_RDONLY)) >= 0) {
            remain++;
            /*
             * We set POLLPRI to detect system processes.
             * We will get POLLNVAL below for a POLLPRI
             * requested event on a system process.
             */
            pfd->events = POLLPRI;
            pfd->revents = 0;
        } else if (errno == ENOENT) {
            (void) fprintf(stderr, "%s: no such process: %s\n",
                command, arg);
        } else {
            perror(arg);
        }
    }

    while (remain != 0) {
        while (poll(pollfd, argc, INFTIM) < 0) {
            if (errno != EAGAIN) {
                perror("poll");
                return (2);
            }
            (void) sleep(2);
        }
        for (i = 0; i < argc; i++) {
            pfd = &pollfd[i];
            if (pfd->fd < 0 || (pfd->revents & ~POLLPRI) == 0) {
                /*
                 * We don't care if a non-system process
                 * stopped.  Don't check for that again.
                 */
                pfd->events = 0;
                pfd->revents = 0;
                continue;
            }

            if (verbose) {
                arg = argv[i];
                if (pfd->revents & POLLHUP) {
                    psinfo_t psinfo;

                    if (pread(pfd->fd, &psinfo,
                        sizeof (psinfo), (off_t)0)
                        == sizeof (psinfo)) {
                        (void) printf(
                    "%s: terminated, wait status 0x%.4x\n",
                            arg, psinfo.pr_wstat);
                    } else {
                        (void) printf(
                            "%s: terminated\n", arg);
                    }
                }
                if (pfd->revents & POLLNVAL)
                    (void) printf("%s: system process\n",
                        arg);
                if (pfd->revents & ~(POLLPRI|POLLHUP|POLLNVAL))
                    (void) printf("%s: unknown error\n",
                        arg);
            }

            (void) close(pfd->fd);
            pfd->fd = -1;
            remain--;
        }
    }

    return (0);
}

/* ARGSUSED1 */
static int
do_count(void *nofilesp, int fd)
{
    (*(int *)nofilesp)++;
    return (0);
}

static int
count_my_files()
{
    int nofiles = 0;

    (void) fdwalk(do_count, &nofiles);
    return (nofiles);
}