usr/src/cmd/streams/strcmd/strconf.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22
  23 /*
  24  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  25  * Use is subject to license terms.
  26  */
  27
  28 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  29 /*        All Rights Reserved   */
  30
  31 #pragma ident   "%Z%%M% %I%     %E% SMI"        /* SVr4.0 1.5   */
  32
  33 /*
  34  * Streams Command strconf:     display the configuration of the
  35  *                              stream associated with stdin.
  36  *
  37  * USAGE:       strconf
  38  *    or:       strconf -m module
  39  *    or:       strconf -t
  40  *
  41  * strconf with no options lists the modules on the stream.
  42  * -m module    echos "yes" and returns 0 if the module is on the stream.
  43  *              echos "no" and returns 2 if not.
  44  * -t           lists only the topmost module.  returns 0 if there is a
  45  *              module, 2 if not.
  46  *
  47  * RETURNS:
  48  *      0       SUCCESS         it works
  49  *      1       ERR_USAGE       bad invocation
  50  *      2       ERR_MODULE      module not there
  51  *      3       ERR_STDIN       an ioctl on the stdin stream failed
  52  *      4       ERR_MEM         couldn't allocate memory
  53  */
  54
  55 #include        <stdio.h>
  56 #include        <sys/stropts.h>
  57 #include        <string.h>
  58 #include        <stdlib.h>
  59 #include        <unistd.h>
  60
  61 #define OPTLIST         "m:t"
  62 #define USAGE           "USAGE: %s [ -m module | -t ]\n"
  63
  64 #define SUCCESS         0
  65 #define FAILURE         1
  66
  67 #define ERR_USAGE       1       /* bad invocation                       */
  68 #define ERR_MODULE      2       /* module not there                     */
  69 #define ERR_STDIN       3       /* an ioctl on the stdin stream failed  */
  70 #define ERR_MEM         4       /* couldn't allocate memory             */
  71
  72 #define NMODULES        16      /* "reasonable" # of modules on a stream  */
  73                                 /*      (there can be more)               */
  74 #define MAXMODULES      2048    /* max # of modules                       */
  75
  76 static char     *Cmd_namep;             /* how was it invoked?  */
  77 static int      more_modules(struct str_list *, int);
  78
  79 int
  80 main(int argc, char **argv)
  81 {
  82         char            *modp;          /* ptr to module name           */
  83         int             i;              /* loop var & junk (what else?) */
  84         boolean_t       mod_present;    /* B_TRUE if -m module          */
  85         boolean_t       topmost;        /* B_TRUE if -t                 */
  86         struct str_mlist mlist[NMODULES]; /* modlist for strlist        */
  87         struct str_list strlist;        /* mods on stream               */
  88
  89         /*
  90          *      init
  91          */
  92         Cmd_namep = argv[0];
  93         mod_present = topmost = B_FALSE;
  94         strlist.sl_nmods = NMODULES;
  95         strlist.sl_modlist = mlist;
  96
  97         /*
  98          *      parse args
  99          */
 100         if (argc > 1) {
 101                 while ((i = getopt(argc, argv, OPTLIST)) != -1) {
 102                         switch (i) {
 103                         case 'm':       /* module present ? */
 104                                 modp = optarg;
 105                                 mod_present = B_TRUE;
 106                                 break;
 107
 108                         case 't':       /* list topmost */
 109                                 topmost = B_TRUE;
 110                                 break;
 111
 112                         default:
 113                                 (void) fprintf(stderr, USAGE, Cmd_namep);
 114                                 return (ERR_USAGE);
 115                         }
 116                 }
 117
 118                 if (optind < argc) {
 119                         (void) fprintf(stderr, USAGE, Cmd_namep);
 120                         return (ERR_USAGE);
 121                 }
 122         }
 123
 124         if (topmost && mod_present) {
 125                 (void) fprintf(stderr,
 126                     "%s: [-t] and [-m] options cannot be used together\n",
 127                     Cmd_namep);
 128                 (void) fprintf(stderr, USAGE, Cmd_namep);
 129                 return (ERR_USAGE);
 130         }
 131
 132         /*
 133          * get number of modules on stream
 134          * allocate more room if needed
 135          */
 136         if ((i = ioctl(STDIN_FILENO, I_LIST, NULL)) < 0) {
 137                 perror("I_LIST");
 138                 (void) fprintf(stderr,
 139                         "%s: I_LIST ioctl failed\n", Cmd_namep);
 140                 return (ERR_STDIN);
 141         }
 142         if (i > strlist.sl_nmods)
 143                 if (more_modules(&strlist, i) != SUCCESS)
 144                         return (ERR_MEM);
 145
 146         /*
 147          *      get list of modules on stream
 148          */
 149         strlist.sl_nmods = i;
 150         if (ioctl(STDIN_FILENO, I_LIST, &strlist) < 0) {
 151                 perror("I_LIST");
 152                 (void) fprintf(stderr, "%s: I_LIST ioctl failed\n", Cmd_namep);
 153                 return (ERR_STDIN);
 154         }
 155
 156         /*
 157          *      list topmost module
 158          */
 159         if (topmost) {
 160                 if (strlist.sl_nmods >= 2) {
 161                         (void) puts(strlist.sl_modlist[0].l_name);
 162                         return (SUCCESS);
 163                 }
 164                 return (ERR_MODULE);
 165         }
 166
 167         /*
 168          *      check if module is present
 169          */
 170         if (mod_present) {
 171                 for (i = 0; i < strlist.sl_nmods; i++) {
 172                         if (strncmp(modp, strlist.sl_modlist[i].l_name,
 173                             FMNAMESZ) == 0) {
 174                                 (void) puts("yes");
 175                                 return (SUCCESS);
 176                         }
 177                 }
 178                 (void) puts("no");
 179                 return (ERR_MODULE);
 180         }
 181
 182         /*
 183          *      print names of all modules and topmost driver on stream
 184          */
 185         for (i = 0; i < strlist.sl_nmods; i++)
 186                 (void) puts(strlist.sl_modlist[i].l_name);
 187         return (SUCCESS);
 188 }
 189
 190 /*
 191  * more_modules(listp, n)       allocate space for 'n' modules in 'listp'
 192  *
 193  * returns:     SUCCESS or FAILURE
 194  */
 195
 196 static int
 197 more_modules(struct str_list *listp, int n)
 198 {
 199         int                     i;
 200         struct str_mlist        *modp;
 201
 202         if (n > MAXMODULES) {
 203                 (void) fprintf(stderr,
 204                     "%s: too many modules (%d) -- max is %d\n",
 205                     Cmd_namep, n, MAXMODULES);
 206                 return (FAILURE);
 207         }
 208
 209         if ((modp = calloc(n, sizeof (struct str_mlist))) == NULL) {
 210                 perror("calloc");
 211                 (void) fprintf(stderr,
 212                     "%s: failed to allocate space for module list\n",
 213                     Cmd_namep);
 214                 return (FAILURE);
 215         }
 216
 217         for (i = 0; i < listp->sl_nmods; ++i)
 218                 (void) strncpy(modp[i].l_name, listp->sl_modlist[i].l_name,
 219                     FMNAMESZ);
 220         listp->sl_nmods = n;
 221         listp->sl_modlist = modp;
 222         return (SUCCESS);
 223 }