/*
 * 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.
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <signal.h>
#include <libproc.h>

static  int     stop(char *);
static  int     lwpstop(int *, const lwpstatus_t *, const lwpsinfo_t *);

static  char    *command;
static  const char *lwps;
static  struct  ps_prochandle *P;

int
main(int argc, char **argv)
{
        int rc = 0;

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

        if (argc <= 1) {
                (void) fprintf(stderr, "usage:\t%s pid[/lwps] ...\n", command);
                (void) fprintf(stderr,
                    "  (stop processes or lwps with /proc request)\n");
                return (2);
        }

        while (--argc > 0)
                rc += stop(*++argv);

        return (rc);
}

static int
stop(char *arg)
{
        int gcode;
        int rc = 0;

        if ((P = proc_arg_xgrab(arg, NULL, PR_ARG_PIDS, PGRAB_RETAIN |
            PGRAB_NOSTOP | PGRAB_FORCE, &gcode, &lwps)) == NULL) {
                (void) fprintf(stderr, "%s: cannot control %s: %s\n",
                    command, arg, Pgrab_error(gcode));
                return (1);
        } else if (lwps != NULL) {
                /*
                 * The user has provided an lwp specification.  Let's consider
                 * the lwp specification as a mask.  We iterate over all lwps in
                 * the process and stop every lwp, which matches the mask.  If
                 * there is no lwp matching the mask or an error occured during
                 * the iteration, set the return code to 1 as indication of an
                 * error.
                 */
                int lwpcount = 0;

                (void) Plwp_iter_all(P, (proc_lwp_all_f *)lwpstop, &lwpcount);
                if (lwpcount == 0) {
                        (void) fprintf(stderr, "%s: cannot control %s:"
                            " no matching LWPs found\n", command, arg);
                        rc = 1;
                } else if (lwpcount == -1)
                        rc = 1;
        } else {
                (void) Pdstop(P);       /* Stop the process. */
        }

        /*
         * Prelease could change the tracing flags, use Pfree and unset
         * run-on-last-close flag to prevent the process being set running
         * after detaching from it.
         */
        (void) Punsetflags(P, PR_RLC);
        Pfree(P);
        return (rc);
}

/* ARGSUSED */
static int
lwpstop(int *lwpcount, const lwpstatus_t *status, const lwpsinfo_t *info)
{
        struct ps_lwphandle *L;
        int gcode;

        if (proc_lwp_in_set(lwps, info->pr_lwpid)) {
                /*
                 * There is a race between the callback from the iterator and
                 * grabbing of the lwp.  If the lwp has already exited, Lgrab
                 * will return the error code G_NOPROC.  It's not a real error,
                 * only if there is no lwp matching the specification.
                 */
                if ((L = Lgrab(P, info->pr_lwpid, &gcode)) != NULL) {
                        (void) Ldstop(L);
                        Lfree(L);
                        if (*lwpcount >= 0)
                                (*lwpcount)++;
                } else if (gcode != G_NOPROC) {
                        (void) fprintf(stderr, "%s: cannot control %d/%d: %s\n",
                            command, (int)Pstatus(P)->pr_pid,
                            (int)info->pr_lwpid, Lgrab_error(gcode));
                        *lwpcount = -1;
                }
        }
        return (0);
}