locate/updatedb.c

   1 /*
   2    updatedb -- build a locate pathname database
   3
   4    Copyright (C) 2007 Free Software Foundation, Inc.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  19    USA.
  20
  21    csh original by James Woods; sh conversion by David MacKenzie.
  22    Rewrite in C by Leslie P. Polzer based on a proposal by James Youngman.
  23
  24 */
  25
  26 #define STR(a) printf("STR: %s=%s\n", #a, a); /* FIXME: debug */
  27
  28 #include "locatedb.h"
  29
  30 //#include <sys/types.h>
  31 #include <sys/wait.h>
  32
  33 #include <stdlib.h>
  34 #include <stdio.h>
  35 #include <stdarg.h>
  36
  37 #include <getopt.h>
  38
  39 #include "../gnulib/lib/tempname.h"
  40 #include "../gnulib/lib/error.h"
  41
  42 /*
  43  * 1. find
  44  * 2. sort
  45  * 3. encode
  46  * 4. write
  47  *
  48  * we need to be very portable, so use several approaches varying in
  49  * performance.
  50  *
  51  * in order of preference:
  52  *
  53  *      - use pthreads or clone(), exec() and a shared piece of memory that
  54  *        naturally comes with them.  do as many things as possible in memory
  55  *        while waiting on disk i/o generated by ``find''.
  56  *
  57  *      - use fork(), exec() and a shared memory area obtained with shmget()
  58  *
  59  *      - vfork is avoided as we can't rely on it.
  60  *
  61  *      - use temporary files for everything as in the original updatedb shell
  62  *        script
  63  *
  64  * the following environment variables and command-line arguments affect this
  65  * program:
  66  *
  67  *      - FINDOPTIONS
  68  *      - SHELL
  69  *      - SEARCHPATHS
  70  *      - NETPATHS
  71  *      - PRUNEPATHS
  72  *      - PRUNEREGEX
  73  *      - PRUNEFS
  74  *      - LOCATE_DB
  75  *      - NETUSER
  76  *      - LIBEXECDIR
  77  *      - BINDIR
  78  *
  79  * TODO:
  80  *
  81  *      * remember temporary files and subprocesses and clean them
  82  *        up on signal/exit
  83  *
  84  *      * give up root privileges whenever possible (see seteuid(3),
  85  *        probably POSIX capabilities).  see locate.c.
  86  *
  87  *      * updatedb needs to be callable by an ordinary user
  88  *        without issues
  89  *
  90  *      * -q switch for only serious errors
  91  *
  92  *      (* -q -q switch for not even serious errors)
  93  *
  94  *
  95  * Configuration system:
  96  *
  97  *      1. command-line arguments
  98  *      2. environment variables
  99  *      3. defaults
 100  *
 101  *      strategy: we fill in 1) with getopt. then we fill in the empty
 102  *      strings with stuff from the env. after that, still empty strings
 103  *      get filled with their defaults.
 104  */
 105
 106 struct map
 107 {
 108     char *key;
 109     char *value;
 110 };
 111
 112 static struct map DEFAULTS[] =
 113 {
 114     { "PRUNEFS", "/proc" },
 115     { "LOCATE_DB", "/etc/locatedb"},
 116     NULL
 117 };
 118
 119 struct config
 120 {
 121     char *findoptions;
 122     char *shell;
 123     char *searchpaths;
 124     char *netpaths;
 125     char *prunepaths;
 126     char *pruneregex;
 127     char *prunefs;
 128     char *locate_db;
 129     char *netuser;
 130     char *libexecdir;
 131     char *bindir;
 132     char *tmpdir;
 133
 134     char *changeto;
 135
 136     int old_format;
 137 };
 138
 139 static struct config CFG =
 140 {
 141     "", /* findoptions */
 142     "/bin/sh", /* shell */
 143     "", /* searchpaths */
 144     "", /* netpaths */
 145     "/tmp /usr/tmp /var/tmp /afs /amd /sfs /proc", /* prunepaths */
 146     "", /* pruneregex */
 147     "nfs NFS proc afs proc smbfs autofs iso9660 ncpfs coda devpts ftpfs devfs mfs sysfs shfs", /* prunefs */
 148     LOCATE_DB, /* locate_db */
 149     "daemon", /* netuser */
 150     LIBEXECDIR, /* libexecdir */
 151     BINDIR /* bindir */
 152     "", /* tmpdir */
 153     "/", /* changeto */
 154     0 /* old_format */
 155 };
 156
 157
 158
 159 #define xgetenv(var, default) \
 160         (getenv(var) != NULL ? getenv(var) : default)
 161
 162 static char*
 163 sprintf_alloc(char *target, const char *fmt, ...)
 164 {
 165 }
 166
 167
 168 static void
 169 xsystem(char *cmd)
 170 {
 171     int r = system(cmd);
 172
 173     if (r == -1)
 174         error(1, 0, "failed to fork");
 175     else
 176         printf("exit status of %s: %d\n", cmd, WEXITSTATUS(r));
 177
 178     return;
 179 }
 180
 181
 182 static char*
 183 get_default(char *key)
 184 {
 185     struct map *m = DEFAULTS;
 186
 187     while (m)
 188     {
 189         if (strcmp(m->key, key) == 0)
 190             return m->value;
 191         m++;
 192     }
 193
 194     return ""; /* no default */
 195 }
 196
 197
 198 static void
 199 updatedb_dumb()
 200 {
 201 /* XXX temporary defines */
 202 #if 0
 203 #define BINDIR "/usr/bin"
 204     char *tmp_find = strdup("updatedb.find.XXXXXX");
 205     char *tmp_sort = strdup("updatedb.sort.XXXXXX");
 206     char *tmp_frcode = strdup("updatedb.frcode.XXXXXX");
 207     char *bindir = xgetenv("BINDIR", BINDIR);
 208     char *find_command;
 209     char *find_invocation = malloc(MAC2048);
 210
 211     find_command = malloc(strlen(BINDIR) + 4 + 1);
 212     strcpy(find_command, bindir);
 213     strcat(find_command, "/find");
 214 #ifdef SORT_SUPPORTS_Z
 215     strcat(find_command, " -print0");
 216 #endif
 217
 218     gen_tempname(tmp_find, GT_NOCREATE);
 219     xsystem("find /home/sky/tmp/TESTDIR -print0 > /tmp/tmp.find");
 220
 221     gen_tempname(tmp_sort, GT_NOCREATE);
 222     xsystem("sort -f -z /tmp/tmp.find > /tmp/tmp.sort");
 223
 224     gen_tempname(tmp_frcode, GT_NOCREATE);
 225     xsystem("/usr/libexec/frcode < /tmp/tmp.sort > /tmp/tmp.frcode");
 226
 227 #endif
 228     return;
 229 }
 230
 231 static void
 232 usage(FILE* out)
 233 {
 234     fprintf(out,
 235         "Usage: updatedb [--findoptions='-option1 -option2...']\n"
 236        "\t[--localpaths='dir1 dir2...'] [--netpaths='dir1 dir2...']\n"
 237        "\t[--prunepaths='dir1 dir2...'] [--prunefs='fs1 fs2...']\n"
 238        "\t[--output=dbfile] [--netuser=user] [--localuser=user]\n"
 239        "\t[--old-format] [--version] [--help]\n"
 240        "\n"
 241        "Report bugs to <bug-findutils@gnu.org>.");
 242
 243     return;
 244 }
 245
 246 static void
 247 parse_options(int* ac, char*** av)
 248 {
 249     enum option_ids /* return values for getopt_long */
 250     {
 251         OPT_FINDOPTIONS,
 252         OPT_SHELL,
 253         OPT_SEARCHPATHS,
 254         OPT_NETPATHS,
 255         OPT_PRUNEPATHS,
 256         OPT_PRUNEREGEX,
 257         OPT_PRUNEFS,
 258         OPT_LOCATE_DB,
 259         OPT_NETUSER,
 260         OPT_LIBEXECDIR,
 261         OPT_BINDIR,
 262         OPT_CHANGECWD
 263     };
 264
 265     static struct option const longopts[] =
 266     {
 267       {"findoptions", required_argument, NULL, OPT_FINDOPTIONS},
 268       {"shell", required_argument, NULL, OPT_SHELL},
 269       {"localpaths", required_argument, NULL, OPT_SEARCHPATHS},
 270       {"netpaths", required_argument, NULL, OPT_NETPATHS},
 271       {"prunepaths", required_argument, NULL, OPT_PRUNEPATHS},
 272       {"pruneregex", required_argument, NULL, OPT_PRUNEREGEX},
 273       {"prunefs", required_argument, NULL, OPT_PRUNEFS},
 274       {"output", required_argument, NULL, OPT_LOCATE_DB},
 275       {"netuser", required_argument, NULL, OPT_NETUSER},
 276       {"libexecdir", required_argument, NULL, OPT_LIBEXECDIR},
 277       {"bindir", required_argument, NULL, OPT_BINDIR},
 278       {"changecwd", required_argument, NULL, OPT_CHANGECWD},
 279
 280       {"old-format", no_argument, &CFG.old_format, 1},
 281
 282       {"help", required_argument, NULL, 'h'},
 283       {"version", required_argument, NULL, 'v'},
 284
 285       {NULL, no_argument, NULL, 0}
 286     };
 287
 288     int optc;
 289
 290     while ((optc = getopt_long (*ac, *av, "h", longopts, (int *) 0)) != -1)
 291         switch (optc)
 292         {
 293             case 'h':
 294                 usage(stdout);
 295                 exit(EXIT_SUCCESS);
 296                 break;
 297
 298             case 'v':
 299
 300             case OPT_FINDOPTIONS:
 301                 break;
 302
 303             case OPT_SHELL:
 304                 break;
 305
 306             case OPT_SEARCHPATHS:
 307                 break;
 308
 309             case OPT_NETPATHS:
 310                 break;
 311
 312             case OPT_PRUNEPATHS:
 313                 break;
 314
 315             case OPT_PRUNEREGEX:
 316                 break;
 317
 318             case OPT_PRUNEFS:
 319                 break;
 320
 321             case OPT_LOCATE_DB:
 322                 break;
 323
 324             case OPT_NETUSER:
 325                 break;
 326
 327             case OPT_LIBEXECDIR:
 328                 break;
 329
 330             case OPT_BINDIR:
 331                 break;
 332
 333             case OPT_CHANGECWD:
 334                 break;
 335
 336             default:
 337                 usage(stderr);
 338                 exit(EXIT_FAILURE);
 339         }
 340
 341 }
 342
 343 static void
 344 build_config()
 345 {
 346 }
 347
 348
 349
 350
 351 int
 352 main (int argc, char **argv)
 353 {
 354     updatedb_dumb();
 355
 356     printf("%s\n", get_default("PRUNEFS"));
 357
 358     parse_options (&argc, &argv);
 359
 360     return 0;
 361 }
 362