/* xsh_ns.c  - xsh_ns */

#include 
#include 

/*------------------------------------------------------------------------
 * xsh_ns - shell command to print info from the device switch table
 *------------------------------------------------------------------------
 */
shellcmd xsh_ns (
         int    nargs,                  /* Number of arguments          */
         char   *args[]                 /* List of arguments            */
        )
{
        int32   i;                      /* Walks through the namespace  */
        struct  nmentry *nptr;          /* Pointer to a namespace entry */
        char    *pptr;                  /* Pointer to a prefix          */
        char    *rptr;                  /* Pointer to a replacement     */
        char    nullstr[] = "NULLSTR";  /* Used when an item is ""      */
        char    repname[NM_MAXLEN];     /* Buffer to hold a mapped name */
        did32   dev;                    /* Device for a mapped name     */
        int32   slen;                   /* Length of an argument        */
        int32   cpylen;                 /* Bytes to copy                */
        int32   d;                      /* Walks through devtab         */

        char    err[] = "invalid arguments - type  --help for details";
        char    *use[] = {
        "With no arguments, ns prints the namespace.  Arguments are",
        "interpreted as follows:",
        "    --help         displays this message.",
        "    -d prefix      removes the prefix from the namspace",
        "    -m ppp rrr ddd mount a namespace entry with prefix ppp,",
        "                     repalcement rrr and device name ddd",
        "    xxx           causes ns to map file name xxx through",
        "                    the namspace and display the result."
        };

        if ( (nargs == 4) || (nargs > 5) ) {

                return 1;
        }

        /* Handle no arguments by dumping the namespace */

        if (nargs == 1) {
                if (nnames <= 0) {
                        fprintf(stderr, "namespace is empty!\n");
                        return 1;
                }
                printf("%s  %s  %s\n",
                        "       Prefix          ",
                        "    Replacement        ",
                        "      Device       ");
                printf("%s  %s  %s\n",
                        "-----------------------",
                        "-----------------------",
                        "-------------------");
                /* Walk through the namespace */
                for (i=0; inprefix;
                        if (*pptr == NULLCH) {
                                pptr = nullstr;
                        }
                        rptr = nptr->nreplace;
                        if (*rptr == NULLCH) {
                                rptr = nullstr;
                        }
                        printf("%-24s %-24s %s\n", pptr, rptr,
                                devtab[nptr->ndevice].dvname);
                }
                return 0;
        }

        /* Handle the case of one argument by mapping the name */

        if (nargs == 2) {

                if (strncmp(args[1], "--help", 7) == 0) {
                        fprintf(stderr, "use:\n  %s\n  %s\n  %s\n  ",
                                use[0], use[1], use[2]);
                        fprintf(stderr,"%s\n  %s\n  %s\n\n",
                                use[3], use[4], use[5]);
                        return 0;
                }
                if (args[1][0] == NULLCH) {
                        fprintf(stderr, "%s\n", err);
                        return 1;
                }
                dev = namrepl(args[1], repname);
                printf(" %s becomes %s on device %d\n",
                                args[1], repname, dev);
                return 0;
        }

        /* Handle the -d option */

        if (nargs == 3) {

                if (strncmp(args[1], "-d", 3) != 0) {
                        fprintf(stderr, "%s\n", err);
                        return 1;
                }
                slen = strlen(args[2]) + 1;
                for (i=0; inprefix, slen)
                                                                == 0) {
                            cpylen = (nnames-i-1)*sizeof(struct nmentry);
                            if (cpylen > 0) {
                                memcpy((void *)nptr,(void *)&nametab[i+1],
                                        cpylen);
                            }
                            nnames--;
                            return 0;
                        }
                }
                fprintf(stderr, "No such entry in the namepace\n");
                return 1;
        }

        /* Handle the -m option */
        if ( strncmp(args[1], "-m", 2) != 0 ) {
                fprintf(stderr, "%s\n", err);
                return 1;
        }
        slen = strlen(args[4]);
        for (d=0; d < NDEVS; d++) {
                if (strncmp(args[4], devtab[d].dvname, slen) == 0) {
                        mount(args[2], args[3], d);
                        return 0;
                }
        }
        fprintf(stderr, "invalid device name\n");
        return 1;
}