usr/src/cmd/dfs.cmds/dfshares/dfshares.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 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  23 /*        All Rights Reserved   */
  24
  25
  26 /*
  27  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  28  * Use is subject to license terms.
  29  */
  30
  31 #pragma ident   "%Z%%M% %I%     %E% SMI"
  32
  33 /*
  34  *      generic interface to dfshares, dfmounts.
  35  *
  36  *      usage:  dfshares [-F fstype] [-o fs_options] [-h] [ args ]
  37  *
  38  *      exec's /usr/lib/fs/<fstype>/<cmd>
  39  *      <cmd> is the basename of the command.
  40  *
  41  *      if -F is missing, fstype is the first entry in /etc/dfs/fstypes
  42  */
  43
  44 #include <sys/types.h>
  45 #include <sys/stat.h>
  46 #include <ctype.h>
  47 #include <stdio.h>
  48 #include <dirent.h>
  49 #include <string.h>
  50 #include <errno.h>
  51 #include <unistd.h>
  52 #include <wait.h>
  53 #include <stdlib.h>
  54
  55 #define DFSTYPES        "/etc/dfs/fstypes"              /* dfs list */
  56 #define FSCMD           "/usr/lib/fs/%s/%s"
  57
  58 /*
  59  * non-[arg...] elements in new argv list:
  60  * cmd name, , -h, -o, opts, (char *)0 terminator
  61  */
  62 #define ARGVPAD         5
  63
  64 static char *getfs(FILE *);
  65 static int invalid(const char *, FILE *);
  66
  67 int
  68 main(int argc, char **argv)
  69 {
  70         FILE *dfp;              /* fp for dfs list */
  71         int c, err = 0;
  72         char subcmd[BUFSIZ];    /* fs specific command */
  73         char *cmd;              /* basename of this command */
  74         char *fsname = NULL;    /* file system name */
  75         char *opts = NULL;      /* -o options */
  76         char **nargv;           /* new argv list */
  77         int hflag = 0;
  78         int nargc = 0;          /* new argc */
  79         pid_t pid;              /* pid for fork */
  80         int retval;             /* exit status from exec'd commad */
  81         int showall = (argc <= 1);      /* show all resources */
  82         static char usage[] =
  83                 "usage: %s [-F fstype] [-h] [-o fs_options ] [arg ...]\n";
  84
  85         cmd = strrchr(argv[0], '/');    /* find the basename */
  86         if (cmd)
  87                 ++cmd;
  88         else
  89                 cmd = argv[0];
  90
  91         while ((c = getopt(argc, argv, "hF:o:")) != -1)
  92                 switch (c) {
  93                 case 'h':
  94                         hflag = 1;      /* no header ... pass to subcommand */
  95                         break;
  96                 case 'F':
  97                         err |= (fsname != NULL);        /* at most one -F */
  98                         fsname = optarg;
  99                         break;
 100                 case 'o':               /* fs specific options */
 101                         err |= (opts != NULL);  /* at most one -o */
 102                         opts = optarg;
 103                         break;
 104                 case '?':
 105                         err = 1;
 106                         break;
 107                 }
 108         if (err) {
 109                 (void) fprintf(stderr, usage, cmd);
 110                 exit(1);
 111         }
 112
 113         if ((dfp = fopen(DFSTYPES, "r")) == NULL) {
 114                 (void) fprintf(stderr, "%s: cannot open %s\n", cmd, DFSTYPES);
 115                 exit(1);
 116         }
 117
 118         /* allocate a block for the new argv list */
 119         if (!(nargv = (char **)malloc(sizeof (char *)*(argc-optind+ARGVPAD)))) {
 120                 (void) fprintf(stderr, "%s: malloc failed.\n", cmd);
 121                 exit(1);
 122         }
 123         nargv[nargc++] = cmd;
 124         if (hflag)
 125                 nargv[nargc++] = "-h";
 126         if (opts) {
 127                 nargv[nargc++] = "-o";
 128                 nargv[nargc++] = opts;
 129         }
 130         for (; optind <= argc; ++optind)        /* this copies the last NULL */
 131                 nargv[nargc++] = argv[optind];
 132
 133         if (showall) {          /* command with no args -- show all dfs's */
 134                 while (fsname = getfs(dfp)) {
 135                         (void) snprintf(subcmd, sizeof (subcmd),
 136                             FSCMD, fsname, cmd);
 137                         switch (pid = fork()) {         /* do the subcommand */
 138                         case 0:
 139                                 (void) execvp(subcmd, nargv);
 140                                 if (errno != ENOENT)
 141                                         perror(subcmd);
 142                                 _exit(1);
 143                                 /*NOTREACHED*/
 144                         default:
 145                                 while (wait(&retval) != pid)
 146                                         ;
 147                                 /* take exit status into account */
 148                                 err |= (retval & 0xff00) >> 8;
 149                                 break;
 150                         case -1:
 151                                 (void) fprintf(stderr,
 152                                         "%s: fork failed - try again later.\n",
 153                                         cmd);
 154                                 exit(1);
 155                         }
 156                 }
 157                 (void) fclose(dfp);
 158                 if (pid == 0) {         /* we never got into the loop! */
 159                         (void) fprintf(stderr,
 160                                     "%s: no file systems in %s\n",
 161                                     cmd, DFSTYPES);
 162                         (void) fprintf(stderr, usage, cmd);
 163                         exit(1);
 164                 }
 165                 else
 166                         exit(err);
 167         }
 168
 169         if (fsname) {           /* generate fs specific command name */
 170                 if (invalid(fsname, dfp)) {     /* valid ? */
 171                         (void) fprintf(stderr,
 172                                     "%s: invalid file system name\n", cmd);
 173                         (void) fprintf(stderr, usage, cmd);
 174                         exit(1);
 175                 }
 176                 else
 177                         (void) snprintf(subcmd, sizeof (subcmd),
 178                             FSCMD, fsname, cmd);
 179         } else if (fsname = getfs(dfp))         /* use 1st line in dfstypes */
 180                 (void) snprintf(subcmd, sizeof (subcmd), FSCMD, fsname, cmd);
 181         else {
 182                 (void) fprintf(stderr,
 183                             "%s: no file systems in %s\n", cmd, DFSTYPES);
 184                 (void) fprintf(stderr, usage, cmd);
 185                 exit(1);
 186         }
 187
 188         (void) execvp(subcmd, nargv);
 189         perror(subcmd);                         /* execvp failed */
 190         return (1);
 191 }
 192
 193
 194 /*
 195  *      invalid(name, f)  -  return non-zero if name is not in
 196  *                           the list of fs names in file f
 197  */
 198
 199 static int
 200 invalid(const char *name,       /* file system name */
 201         FILE *f)                /* file of list of file system types */
 202 {
 203         char *s;
 204
 205         while (s = getfs(f))    /* while there's still hope ... */
 206                 if (strcmp(s, name) == 0)
 207                         return (0);     /* we got it! */
 208         return (1);
 209 }
 210
 211
 212 /*
 213  *   getfs(fp) - get the next file system name from fp
 214  *               ignoring lines starting with a #.
 215  *               All leading whitespace is discarded.
 216  */
 217
 218 static char buf[BUFSIZ];
 219
 220 static char *
 221 getfs(FILE *fp)
 222 {
 223         register char *s;
 224
 225         while (s = fgets(buf, BUFSIZ, fp)) {
 226                 while (isspace(*s))     /* leading whitespace doesn't count */
 227                         ++s;
 228                 if (*s != '#') {        /* not a comment */
 229                         char *t = s;
 230
 231                         while (!isspace(*t))    /* get the token */
 232                                 ++t;
 233                         *t = '\0';              /* ignore rest of line */
 234                         return (s);
 235                 }
 236         }
 237         return (NULL);  /* that's all, folks! */
 238 }