source: MondoRescue/trunk/mindi-busybox/util-linux/ipcrm.c@ 956

/*
 * ipcrm.c -- utility to allow removal of IPC objects and data structures.
 *
 * 01 Sept 2004 - Rodney Radford <rradford@mindspring.com>
 * Adapted for busybox from util-linux-2.12a.
 *
 * 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 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * --- Pre-busybox history from util-linux-2.12a ------------------------
 *
 * 1999-04-02 frank zago
 * - can now remove several id's in the same call
 *
 * 1999-02-22 Arkadiusz Miÿkiewicz <misiek@pld.ORG.PL>
 * - added Native Language Support
 *
 * Original author - krishna balasubramanian 1993
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/msg.h>
#include <sys/sem.h>

/* X/OPEN tells us to use <sys/{types,ipc,sem}.h> for semctl() */
/* X/OPEN tells us to use <sys/{types,ipc,msg}.h> for msgctl() */
/* for getopt */
#include <unistd.h>

/* for tolower and isupper */
#include <ctype.h>

#include "busybox.h"

#if defined (__GNU_LIBRARY__) && !defined(_SEM_SEMUN_UNDEFINED)
/* union semun is defined by including <sys/sem.h> */
#else
/* according to X/OPEN we have to define it ourselves */
union semun {
    int val;
    struct semid_ds *buf;
    unsigned short int *array;
    struct seminfo *__buf;
};
#endif

typedef enum type_id {
    SHM,
    SEM,
    MSG
} type_id;

static int
remove_ids(type_id type, int argc, char **argv) {
    int id;
    int ret = 0;        /* for gcc */
    char *end;
    int nb_errors = 0;
    union semun arg;

    arg.val = 0;

    while(argc) {

        id = strtoul(argv[0], &end, 10);

        if (*end != 0) {
            bb_printf ("invalid id: %s\n", argv[0]);
            nb_errors ++;
        } else {
            switch(type) {
            case SEM:
                ret = semctl (id, 0, IPC_RMID, arg);
                break;

            case MSG:
                ret = msgctl (id, IPC_RMID, NULL);
                break;

            case SHM:
                ret = shmctl (id, IPC_RMID, NULL);
                break;
            }

            if (ret) {
                bb_printf ("cannot remove id %s (%s)\n",
                    argv[0], strerror(errno));
                nb_errors ++;
            }
        }
        argc--;
        argv++;
    }

    return(nb_errors);
}

static int deprecated_main(int argc, char **argv)
{
    if (argc < 3) {
        bb_show_usage();
        bb_fflush_stdout_and_exit(1);
    }

    if (!strcmp(argv[1], "shm")) {
        if (remove_ids(SHM, argc-2, &argv[2]))
            bb_fflush_stdout_and_exit(1);
    }
    else if (!strcmp(argv[1], "msg")) {
        if (remove_ids(MSG, argc-2, &argv[2]))
            bb_fflush_stdout_and_exit(1);
    }
    else if (!strcmp(argv[1], "sem")) {
        if (remove_ids(SEM, argc-2, &argv[2]))
            bb_fflush_stdout_and_exit(1);
    }
    else {
        bb_printf ("unknown resource type: %s\n", argv[1]);
        bb_show_usage();
        bb_fflush_stdout_and_exit(1);
    }

    bb_printf ("resource(s) deleted\n");
    return 0;
}


int ipcrm_main(int argc, char **argv)
{
    int   c;
    int   error = 0;
    char *prog = argv[0];

    /* if the command is executed without parameters, do nothing */
    if (argc == 1)
        return 0;

    /* check to see if the command is being invoked in the old way if so
       then run the old code */
    if (strcmp(argv[1], "shm") == 0 ||
        strcmp(argv[1], "msg") == 0 ||
        strcmp(argv[1], "sem") == 0)
        return deprecated_main(argc, argv);

    /* process new syntax to conform with SYSV ipcrm */
    while ((c = getopt(argc, argv, "q:m:s:Q:M:S:h?")) != -1) {
        int result;
        int id = 0;
        int iskey = isupper(c);

        /* needed to delete semaphores */
        union semun arg;
        arg.val = 0;

        if ((c == '?') || (c == 'h'))
        {
            bb_show_usage();
            return 0;
        }

        /* we don't need case information any more */
        c = tolower(c);

        /* make sure the option is in range */
        if (c != 'q' && c != 'm' && c != 's') {
            bb_show_usage();
            error++;
            return error;
        }

        if (iskey) {
            /* keys are in hex or decimal */
            key_t key = strtoul(optarg, NULL, 0);
            if (key == IPC_PRIVATE) {
                error++;
                bb_fprintf(stderr, "%s: illegal key (%s)\n",
                    prog, optarg);
                continue;
            }

            /* convert key to id */
            id = ((c == 'q') ? msgget(key, 0) :
                  (c == 'm') ? shmget(key, 0, 0) :
                  semget(key, 0, 0));

            if (id < 0) {
                char *errmsg;
                error++;
                switch(errno) {
                case EACCES:
                    errmsg = "permission denied for key";
                    break;
                case EIDRM:
                    errmsg = "already removed key";
                    break;
                case ENOENT:
                    errmsg = "invalid key";
                    break;
                default:
                    errmsg = "unknown error in key";
                    break;
                }
                bb_fprintf(stderr, "%s: %s (%s)\n",
                    prog, errmsg, optarg);
                continue;
            }
        } else {
            /* ids are in decimal */
            id = strtoul(optarg, NULL, 10);
        }

        result = ((c == 'q') ? msgctl(id, IPC_RMID, NULL) :
              (c == 'm') ? shmctl(id, IPC_RMID, NULL) :
              semctl(id, 0, IPC_RMID, arg));

        if (result < 0) {
            char *errmsg;
            error++;
            switch(errno) {
            case EACCES:
            case EPERM:
                errmsg = iskey
                    ? "permission denied for key"
                    : "permission denied for id";
                break;
            case EINVAL:
                errmsg = iskey
                    ? "invalid key"
                    : "invalid id";
                break;
            case EIDRM:
                errmsg = iskey
                    ? "already removed key"
                    : "already removed id";
                break;
            default:
                errmsg = iskey
                    ? "unknown error in key"
                    : "unknown error in id";
                break;
            }
            bb_fprintf(stderr, "%s: %s (%s)\n",
                prog, errmsg, optarg);
            continue;
        }
    }

    /* print usage if we still have some arguments left over */
    if (optind != argc) {
        bb_show_usage();
    }

    /* exit value reflects the number of errors encountered */
    return error;
}