/*
 * 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 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <sys/types.h>
#include <sys/wait.h>
#include <sys/ctfs.h>
#include <sys/contract/process.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <libcontract.h>
#include <libcontract_priv.h>
#include <libuutil.h>
#include <poll.h>
#include <port.h>
#include <signal.h>
#include <sys/wait.h>
#include <stdarg.h>

#include <locale.h>
#include <langinfo.h>

struct {
        const char *name;
        int found;
} types[] = {
        { "process", 0 },
        { "device", 0 },
        { NULL }
};

typedef struct watched_fd {
        int wf_fd;
        int wf_type;
} watched_fd_t;

/*
 * usage
 *
 * Educate the user.
 */
static void
usage(void)
{
        (void) fprintf(stderr, gettext(
            "Usage: %s [-f] [-r] [-v] contract-id | contract-type ...\n"),
            uu_getpname());
        exit(UU_EXIT_USAGE);
}

/*
 * sopen
 *
 * Given a format string and a variable number of arguments, create a
 * file name and open it.  Warn with 'permerror' and return -1 if
 * opening the file returned EPERM or EACCES, die with 'error' on all
 * other error conditions.
 */
static int
sopen(const char *format, const char *error, const char *permerror, ...)
{
        char path[PATH_MAX];
        int fd;
        va_list varg;

        va_start(varg, permerror);
        if (vsnprintf(path, PATH_MAX, format, varg) >= PATH_MAX) {
                errno = ENAMETOOLONG;
                uu_vdie(error, varg);
        }

        if ((fd = open64(path, O_RDONLY | O_NONBLOCK)) == -1) {
                if (permerror && (errno == EPERM || errno == EACCES))
                        uu_vwarn(permerror, varg);
                else
                        uu_vdie(error, varg);
        }
        va_end(varg);

        return (fd);
}

/*
 * hdr_event
 *
 * Display the output header.
 */
static void
hdr_event(void)
{
        (void) printf("%-8s%-8s%-5s%-4s%-9s%s\n",
            "CTID", "EVID", "CRIT", "ACK", "CTTYPE", "SUMMARY");
}

/*
 * get_event
 *
 * Read and display a contract event.
 */
static int
get_event(int fd, int type, int verbose)
{
        ct_evthdl_t ev;
        uint_t flags;

        /*
         * Read a contract event.
         */
        if (errno = ct_event_read(fd, &ev)) {
                if (errno == EAGAIN)
                        return (0);
                uu_die(gettext("could not receive contract event"));
        }

        /*
         * Emit a one-line event summary.
         */
        flags = ct_event_get_flags(ev);
        (void) printf("%-8ld%-8lld%-5s%-4s%-9s",
            ct_event_get_ctid(ev),
            ct_event_get_evid(ev),
            (flags & CTE_INFO) ? "info" : (flags & CTE_NEG) ? "neg" : "crit",
            flags & CTE_ACK ? "yes" : "no",
            types[type].name);

        /*
         * Display event details, if requested.
         * (Since this is also needed by ctrun, the common
         * contract_event_dump is found in libcontract.)
         */
        contract_event_dump(stdout, ev, verbose);

        ct_event_free(ev);
        return (1);
}

/*
 * get_type
 *
 * Given a contract type name, return an index into the 'types' array.
 * Exits on failure.
 */
static int
get_type(const char *typestr)
{
        int i;
        for (i = 0; types[i].name; i++)
                if (strcmp(types[i].name, typestr) == 0)
                        return (i);
        uu_die(gettext("invalid contract type: %s\n"), typestr);
        /* NOTREACHED */
}

/*
 * contract_type
 *
 * Given a contract id, return an index into the 'types' array.
 * Returns -1 on failure.
 */
static int
contract_type(ctid_t id)
{
        ct_stathdl_t hdl;
        int type, fd;

        /*
         * This could be faster (e.g. by reading the link itself), but
         * this is the most straightforward implementation.
         */
        if ((fd = contract_open(id, NULL, "status", O_RDONLY)) == -1)
                return (-1);
        if (errno = ct_status_read(fd, CTD_COMMON, &hdl)) {
                (void) close(fd);
                return (-1);
        }
        type = get_type(ct_status_get_type(hdl));
        ct_status_free(hdl);
        (void) close(fd);
        return (type);
}

/*
 * ctid_compar
 *
 * A simple contract ID comparator.
 */
static int
ctid_compar(const void *a1, const void *a2)
{
        ctid_t id1 = *(ctid_t *)a1;
        ctid_t id2 = *(ctid_t *)a2;

        if (id1 > id2)
                return (1);
        if (id2 > id1)
                return (-1);
        return (0);
}

int
main(int argc, char **argv)
{
        int     opt_reliable = 0;
        int     opt_reset = 0;
        int     opt_verbose = 0;
        int     port_fd;
        watched_fd_t *wfd;
        int     i, nfds, nids;
        ctid_t  *ids, last;

        (void) setlocale(LC_ALL, "");
        (void) textdomain(TEXT_DOMAIN);

        (void) uu_setpname(argv[0]);

        while ((i = getopt(argc, argv, "rfv")) !=  EOF) {
                switch (i) {
                case 'r':
                        opt_reliable = 1;
                        break;
                case 'f':
                        opt_reset = 1;
                        break;
                case 'v':
                        opt_verbose = 1;
                        break;
                default:
                        usage();
                }
        }

        argc -= optind;
        argv += optind;

        if (argc <= 0)
                usage();

        wfd = calloc(argc, sizeof (struct pollfd));
        if (wfd == NULL)
                uu_die("calloc");
        ids = calloc(argc, sizeof (ctid_t));
        if (ids == NULL)
                uu_die("calloc");

        /*
         * Scan our operands for contract ids and types.
         */
        nfds = 0;
        nids = 0;
        for (i = 0; i < argc; i++) {
                int id;
                if (strchr(argv[i], '/') != NULL)
                        uu_die(gettext("invalid contract type: %s\n"), argv[i]);

                /*
                 * If argument isn't a number between 0 and INT_MAX,
                 * treat it as a contract type.
                 */
                if (uu_strtoint(argv[i], &id, sizeof (id), 10, 1, INT_MAX)) {
                        int type;
                        wfd[nfds].wf_fd =
                            sopen(CTFS_ROOT "/%s/bundle",
                            gettext("invalid contract type: %s\n"), NULL,
                            argv[i]);
                        wfd[nfds].wf_type = type = get_type(argv[i]);
                        if (types[type].found) {
                                (void) close(wfd[nfds].wf_fd);
                                continue;
                        }
                        types[type].found = 1;
                        nfds++;
                } else {
                        ids[nids++] = id;
                }
        }

        /*
         * Eliminate those contract ids which are represented by
         * contract types, so we don't get duplicate event reports from
         * them.
         *
         * Sorting the array first allows us to efficiently skip
         * duplicate ids.  We know that the array only contains
         * integers [0, INT_MAX].
         */
        qsort(ids, nids, sizeof (ctid_t), ctid_compar);
        last = -1;
        for (i = 0; i < nids; i++) {
                int type, fd;

                if (ids[i] == last)
                        continue;
                last = ids[i];

                fd = sopen(CTFS_ROOT "/all/%d/events",
                    gettext("invalid contract id: %d\n"),
                    gettext("could not access contract id %d\n"), ids[i]);
                if (fd == -1)
                        continue;
                if ((type = contract_type(ids[i])) == -1) {
                        (void) close(fd);
                        uu_warn(gettext("could not access contract id %d\n"),
                            ids[i]);
                        continue;
                }
                if (types[type].found) {
                        (void) close(fd);
                        continue;
                }
                wfd[nfds].wf_fd = fd;
                wfd[nfds].wf_type = type;
                nfds++;
        }
        free(ids);

        if (nfds == 0)
                uu_die(gettext("no contracts to watch\n"));

        /*
         * Handle options.
         */
        if (opt_reliable)
                for (i = 0; i < nfds; i++)
                        if (ioctl(wfd[i].wf_fd, CT_ERELIABLE, NULL) == -1) {
                                uu_warn("could not request reliable events");
                                break;
                        }

        if (opt_reset)
                for (i = 0; i < nfds; i++)
                        (void) ioctl(wfd[i].wf_fd, CT_ERESET, NULL);


        /*
         * Allocate an event point, and associate all our endpoint file
         * descriptors with it.
         */
        if ((port_fd = port_create()) == -1)
                goto port_error;
        for (i = 0; i < nfds; i++)
                if (port_associate(port_fd, PORT_SOURCE_FD, wfd[i].wf_fd,
                    POLLIN, &wfd[i]) == -1)
                        goto port_error;

        /*
         * Loop waiting for and displaying events.
         */
        hdr_event();
        for (;;) {
                port_event_t pe;
                watched_fd_t *w;
                if (port_get(port_fd, &pe, NULL) == -1) {
                        if (errno == EINTR)
                                continue;
                        goto port_error;
                }
                w = pe.portev_user;
                while (get_event(pe.portev_object, w->wf_type, opt_verbose))
                        ;
                if (port_associate(port_fd, PORT_SOURCE_FD, pe.portev_object,
                    POLLIN, pe.portev_user) == -1)
                        goto port_error;
        }

port_error:
        uu_die(gettext("error waiting for contract events"));

        return (1);     /* placate cc */
}