usr.bin/find/find.c

   1 /*      $NetBSD: find.c,v 1.23 2006/10/11 19:51:10 apb Exp $    */
   2
   3 /*-
   4  * Copyright (c) 1991, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Cimarron D. Taylor of the University of California, Berkeley.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 #ifndef lint
  37 #if 0
  38 static char sccsid[] = "from: @(#)find.c        8.5 (Berkeley) 8/5/94";
  39 #else
  40 __RCSID("$NetBSD: find.c,v 1.23 2006/10/11 19:51:10 apb Exp $");
  41 #endif
  42 #endif /* not lint */
  43
  44 #include <sys/types.h>
  45 #include <sys/stat.h>
  46
  47 #include <err.h>
  48 #include <errno.h>
  49 #include <fts.h>
  50 #include <signal.h>
  51 #include <stdio.h>
  52 #include <string.h>
  53 #include <stdlib.h>
  54
  55 #include "find.h"
  56
  57 static int ftscompare(const FTSENT **, const FTSENT **);
  58
  59 static void sig_lock(sigset_t *);
  60 static void sig_unlock(const sigset_t *);
  61
  62 /*
  63  * find_formplan --
  64  *      process the command line and create a "plan" corresponding to the
  65  *      command arguments.
  66  */
  67 PLAN *
  68 find_formplan(char **argv)
  69 {
  70         PLAN *plan, *tail, *new;
  71
  72         /*
  73          * for each argument in the command line, determine what kind of node
  74          * it is, create the appropriate node type and add the new plan node
  75          * to the end of the existing plan.  The resulting plan is a linked
  76          * list of plan nodes.  For example, the string:
  77          *
  78          *      % find . -name foo -newer bar -print
  79          *
  80          * results in the plan:
  81          *
  82          *      [-name foo]--> [-newer bar]--> [-print]
  83          *
  84          * in this diagram, `[-name foo]' represents the plan node generated
  85          * by c_name() with an argument of foo and `-->' represents the
  86          * plan->next pointer.
  87          */
  88         for (plan = tail = NULL; *argv;) {
  89                 if (!(new = find_create(&argv)))
  90                         continue;
  91                 if (plan == NULL)
  92                         tail = plan = new;
  93                 else {
  94                         tail->next = new;
  95                         tail = new;
  96                 }
  97         }
  98
  99         /*
 100          * if the user didn't specify one of -print, -ok, -fprint, -exec, or
 101          * -exit, then -print is assumed so we bracket the current expression
 102          * with parens, if necessary, and add a -print node on the end.
 103          */
 104         if (!isoutput) {
 105                 if (plan == NULL) {
 106                         new = c_print(NULL, 0);
 107                         tail = plan = new;
 108                 } else {
 109                         new = c_openparen(NULL, 0);
 110                         new->next = plan;
 111                         plan = new;
 112                         new = c_closeparen(NULL, 0);
 113                         tail->next = new;
 114                         tail = new;
 115                         new = c_print(NULL, 0);
 116                         tail->next = new;
 117                         tail = new;
 118                 }
 119         }
 120
 121         /*
 122          * the command line has been completely processed into a search plan
 123          * except for the (, ), !, and -o operators.  Rearrange the plan so
 124          * that the portions of the plan which are affected by the operators
 125          * are moved into operator nodes themselves.  For example:
 126          *
 127          *      [!]--> [-name foo]--> [-print]
 128          *
 129          * becomes
 130          *
 131          *      [! [-name foo] ]--> [-print]
 132          *
 133          * and
 134          *
 135          *      [(]--> [-depth]--> [-name foo]--> [)]--> [-print]
 136          *
 137          * becomes
 138          *
 139          *      [expr [-depth]-->[-name foo] ]--> [-print]
 140          *
 141          * operators are handled in order of precedence.
 142          */
 143
 144         plan = paren_squish(plan);              /* ()'s */
 145         plan = not_squish(plan);                /* !'s */
 146         plan = or_squish(plan);                 /* -o's */
 147         return (plan);
 148 }
 149
 150 static int
 151 ftscompare(const FTSENT **e1, const FTSENT **e2)
 152 {
 153
 154         return (strcoll((*e1)->fts_name, (*e2)->fts_name));
 155 }
 156
 157 static void
 158 sig_lock(sigset_t *s)
 159 {
 160         sigset_t new;
 161
 162         sigemptyset(&new);
 163         sigaddset(&new, SIGINFO); /* block SIGINFO */
 164         sigprocmask(SIG_BLOCK, &new, s);
 165 }
 166
 167 static void
 168 sig_unlock(const sigset_t *s)
 169 {
 170
 171         sigprocmask(SIG_SETMASK, s, NULL);
 172 }
 173
 174 FTS *tree;                      /* pointer to top of FTS hierarchy */
 175 FTSENT *g_entry;                /* shared with SIGINFO handler */
 176
 177 /*
 178  * find_execute --
 179  *      take a search plan and an array of search paths and executes the plan
 180  *      over all FTSENT's returned for the given search paths.
 181  */
 182 int
 183 find_execute(PLAN *plan, char **paths)
 184 {
 185         PLAN *p;
 186         int r, rval, cval;
 187         sigset_t s;
 188
 189         cval = 1;
 190
 191         if (!(tree = fts_open(paths, ftsoptions, issort ? ftscompare : NULL)))
 192                 err(1, "ftsopen");
 193
 194         sig_lock(&s);
 195         for (rval = 0; cval && (g_entry = fts_read(tree)) != NULL; sig_lock(&s)) {
 196                 sig_unlock(&s);
 197                 switch (g_entry->fts_info) {
 198                 case FTS_D:
 199                         if (isdepth)
 200                                 continue;
 201                         break;
 202                 case FTS_DP:
 203                         if (!isdepth)
 204                                 continue;
 205                         break;
 206                 case FTS_DNR:
 207                 case FTS_ERR:
 208                 case FTS_NS:
 209                         (void)fflush(stdout);
 210                         warnx("%s: %s",
 211                             g_entry->fts_path, strerror(g_entry->fts_errno));
 212                         rval = 1;
 213                         continue;
 214                 }
 215 #define BADCH   " \t\n\\'\""
 216                 if (isxargs && strpbrk(g_entry->fts_path, BADCH)) {
 217                         (void)fflush(stdout);
 218                         warnx("%s: illegal path", g_entry->fts_path);
 219                         rval = 1;
 220                         continue;
 221                 }
 222
 223                 /*
 224                  * Call all the functions in the execution plan until one is
 225                  * false or all have been executed.  This is where we do all
 226                  * the work specified by the user on the command line.
 227                  */
 228                 for (p = plan; p && (p->eval)(p, g_entry); p = p->next)
 229                         if (p->type == N_EXIT) {
 230                                 rval = p->exit_val;
 231                                 cval = 0;
 232                         }
 233         }
 234
 235         sig_unlock(&s);
 236         if (errno)
 237                 err(1, "fts_read");
 238         (void)fts_close(tree);
 239
 240         /*
 241          * Cleanup any plans with leftover state.
 242          * Keep the last non-zero return value.
 243          */
 244         if ((r = find_traverse(plan, plan_cleanup, NULL)) != 0)
 245                 rval = r;
 246
 247         return (rval);
 248 }
 249
 250 /*
 251  * find_traverse --
 252  *      traverse the plan tree and execute func() on all plans.  This
 253  *      does not evaluate each plan's eval() function; it is intended
 254  *      for operations that must run on all plans, such as state
 255  *      cleanup.
 256  *
 257  *      If any func() returns non-zero, then so will find_traverse().
 258  */
 259 int
 260 find_traverse(plan, func, arg)
 261         PLAN *plan;
 262         int (*func)(PLAN *, void *);
 263         void *arg;
 264 {
 265         PLAN *p;
 266         int r, rval;
 267
 268         rval = 0;
 269         for (p = plan; p; p = p->next) {
 270                 if ((r = func(p, arg)) != 0)
 271                         rval = r;
 272                 if (p->type == N_EXPR || p->type == N_OR) {
 273                         if (p->p_data[0])
 274                                 if ((r = find_traverse(p->p_data[0],
 275                                             func, arg)) != 0)
 276                                         rval = r;
 277                         if (p->p_data[1])
 278                                 if ((r = find_traverse(p->p_data[1],
 279                                             func, arg)) != 0)
 280                                         rval = r;
 281                 }
 282         }
 283         return rval;
 284 }