/*      $NetBSD: find.c,v 1.30 2016/06/13 00:04:40 pgoyette Exp $       */

/*-
* Copyright (c) 1991, 1993, 1994
*      The Regents of the University of California.  All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Cimarron D. Taylor of the University of California, Berkeley.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "from: @(#)find.c        8.5 (Berkeley) 8/5/94";
#else
__RCSID("$NetBSD: find.c,v 1.30 2016/06/13 00:04:40 pgoyette Exp $");
#endif
#endif /* not lint */

#include <sys/types.h>
#include <sys/stat.h>

#include <err.h>
#include <errno.h>
#include <fts.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
#include <unistd.h>

#include "find.h"

static int ftscompare(const FTSENT **, const FTSENT **);

/*
* find_formplan --
*      process the command line and create a "plan" corresponding to the
*      command arguments.
*/
PLAN *
find_formplan(char **argv)
{
       PLAN *plan, *tail, *new;

       /*
        * for each argument in the command line, determine what kind of node
        * it is, create the appropriate node type and add the new plan node
        * to the end of the existing plan.  The resulting plan is a linked
        * list of plan nodes.  For example, the string:
        *
        *      % find . -name foo -newer bar -print
        *
        * results in the plan:
        *
        *      [-name foo]--> [-newer bar]--> [-print]
        *
        * in this diagram, `[-name foo]' represents the plan node generated
        * by c_name() with an argument of foo and `-->' represents the
        * plan->next pointer.
        */
       for (plan = tail = NULL; *argv;) {
               if (!(new = find_create(&argv)))
                       continue;
               if (plan == NULL)
                       tail = plan = new;
               else {
                       tail->next = new;
                       tail = new;
               }
       }

       /*
        * if the user didn't specify one of -print, -ok, -fprint, -exec, or
        * -exit, then -print is assumed so we bracket the current expression
        * with parens, if necessary, and add a -print node on the end.
        */
       if (!isoutput) {
               if (plan == NULL) {
                       new = c_print(NULL, 0, NULL);
                       tail = plan = new;
               } else {
                       new = c_openparen(NULL, 0, NULL);
                       new->next = plan;
                       plan = new;
                       new = c_closeparen(NULL, 0, NULL);
                       tail->next = new;
                       tail = new;
                       new = c_print(NULL, 0, NULL);
                       tail->next = new;
                       tail = new;
               }
       }

       /*
        * the command line has been completely processed into a search plan
        * except for the (, ), !, and -o operators.  Rearrange the plan so
        * that the portions of the plan which are affected by the operators
        * are moved into operator nodes themselves.  For example:
        *
        *      [!]--> [-name foo]--> [-print]
        *
        * becomes
        *
        *      [! [-name foo] ]--> [-print]
        *
        * and
        *
        *      [(]--> [-depth]--> [-name foo]--> [)]--> [-print]
        *
        * becomes
        *
        *      [expr [-depth]-->[-name foo] ]--> [-print]
        *
        * operators are handled in order of precedence.
        */

       plan = paren_squish(plan);              /* ()'s */
       plan = not_squish(plan);                /* !'s */
       plan = or_squish(plan);                 /* -o's */
       return (plan);
}

static int
ftscompare(const FTSENT **e1, const FTSENT **e2)
{

       return (strcoll((*e1)->fts_name, (*e2)->fts_name));
}

static sigset_t ss;
static bool notty;

static __inline void
sig_init(void)
{
       struct sigaction sa;
       notty = !(isatty(STDIN_FILENO) || isatty(STDOUT_FILENO) ||
           isatty(STDERR_FILENO));
       if (notty)
               return;
       sigemptyset(&ss);
       sigaddset(&ss, SIGINFO); /* block SIGINFO */

       memset(&sa, 0, sizeof(sa));
       sa.sa_flags = SA_RESTART;
       sa.sa_handler = show_path;
       (void)sigaction(SIGINFO, &sa, NULL);

}

static __inline void
sig_lock(sigset_t *s)
{
       if (notty)
               return;
       sigprocmask(SIG_BLOCK, &ss, s);
}

static __inline void
sig_unlock(const sigset_t *s)
{
       if (notty)
               return;
       sigprocmask(SIG_SETMASK, s, NULL);
}

FTS *tree;                      /* pointer to top of FTS hierarchy */
FTSENT *g_entry;                /* shared with SIGINFO handler */

/*
* find_execute --
*      take a search plan and an array of search paths and executes the plan
*      over all FTSENT's returned for the given search paths.
*/
int
find_execute(PLAN *plan, char **paths)
{
       PLAN *p;
       int r, rval, cval;
       sigset_t s;

       cval = 1;

       if (!(tree = fts_open(paths, ftsoptions, issort ? ftscompare : NULL)))
               err(1, "ftsopen");

       sig_init();
       sig_lock(&s);
       for (rval = 0; cval && (g_entry = fts_read(tree)) != NULL;) {
               switch (g_entry->fts_info) {
               case FTS_D:
                       if (isdepth)
                               continue;
                       break;
               case FTS_DP:
                       if (!isdepth)
                               continue;
                       break;
               case FTS_DNR:
               case FTS_ERR:
               case FTS_NS:
                       sig_unlock(&s);
                       (void)fflush(stdout);
                       warnx("%s: %s",
                           g_entry->fts_path, strerror(g_entry->fts_errno));
                       rval = 1;
                       sig_lock(&s);
                       continue;
               }
#define BADCH   " \t\n\\'\""
               if (isxargs && strpbrk(g_entry->fts_path, BADCH)) {
                       sig_unlock(&s);
                       (void)fflush(stdout);
                       warnx("%s: illegal path", g_entry->fts_path);
                       rval = 1;
                       sig_lock(&s);
                       continue;
               }

               /*
                * Call all the functions in the execution plan until one is
                * false or all have been executed.  This is where we do all
                * the work specified by the user on the command line.
                */
               sig_unlock(&s);
               for (p = plan; p && (p->eval)(p, g_entry); p = p->next)
                       if (p->type == N_EXIT) {
                               rval = p->exit_val;
                               cval = 0;
                       }
               sig_lock(&s);
       }

       sig_unlock(&s);
       if (g_entry == NULL && errno)
               err(1, "fts_read");
       (void)fts_close(tree);

       /*
        * Cleanup any plans with leftover state.
        * Keep the last non-zero return value.
        */
       if ((r = find_traverse(plan, plan_cleanup, NULL)) != 0)
               rval = r;

       return (rval);
}

/*
* find_traverse --
*      traverse the plan tree and execute func() on all plans.  This
*      does not evaluate each plan's eval() function; it is intended
*      for operations that must run on all plans, such as state
*      cleanup.
*
*      If any func() returns non-zero, then so will find_traverse().
*/
int
find_traverse(PLAN *plan, int (*func)(PLAN *, void *), void *arg)
{
       PLAN *p;
       int r, rval;

       rval = 0;
       for (p = plan; p; p = p->next) {
               if ((r = func(p, arg)) != 0)
                       rval = r;
               if (p->type == N_EXPR || p->type == N_OR) {
                       if (p->p_data[0])
                               if ((r = find_traverse(p->p_data[0],
                                           func, arg)) != 0)
                                       rval = r;
                       if (p->p_data[1])
                               if ((r = find_traverse(p->p_data[1],
                                           func, arg)) != 0)
                                       rval = r;
               }
       }
       return rval;
}