xref: /openbsd/usr.bin/find/find.c (revision b8a25a12)
1 /*	$OpenBSD: find.c,v 1.23 2018/08/01 06:39:58 tb Exp $	*/
2 
3 /*-
4  * Copyright (c) 1991, 1993
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/types.h>
36 #include <sys/stat.h>
37 
38 #include <err.h>
39 #include <errno.h>
40 #include <fts.h>
41 #include <signal.h>
42 #include <stdio.h>
43 #include <string.h>
44 #include <stdlib.h>
45 #include <unistd.h>
46 
47 int	mayexecve;
48 
49 #include "find.h"
50 
51 /*
52  * find_formplan --
53  *	process the command line and create a "plan" corresponding to the
54  *	command arguments.
55  */
56 PLAN *
find_formplan(char ** argv)57 find_formplan(char **argv)
58 {
59 	PLAN *plan, *tail, *new;
60 
61 	/*
62 	 * for each argument in the command line, determine what kind of node
63 	 * it is, create the appropriate node type and add the new plan node
64 	 * to the end of the existing plan.  The resulting plan is a linked
65 	 * list of plan nodes.  For example, the string:
66 	 *
67 	 *	% find . -name foo -newer bar -print
68 	 *
69 	 * results in the plan:
70 	 *
71 	 *	[-name foo]--> [-newer bar]--> [-print]
72 	 *
73 	 * in this diagram, `[-name foo]' represents the plan node generated
74 	 * by c_name() with an argument of foo and `-->' represents the
75 	 * plan->next pointer.
76 	 */
77 	for (plan = tail = NULL; *argv;) {
78 		if (!(new = find_create(&argv)))
79 			continue;
80 		if (plan == NULL)
81 			tail = plan = new;
82 		else {
83 			tail->next = new;
84 			tail = new;
85 		}
86 	}
87 
88 	/*
89 	 * if the user didn't specify one of -delete, -exec, -execdir,
90 	 * -ls, -ok, -print or -print0, then -print is assumed so we
91 	 * bracket the current expression with parens, if necessary,
92 	 * and add a -print node on the end.
93 	 */
94 	if (!isoutput) {
95 		if (plan == NULL) {
96 			new = c_print(NULL, NULL, 0);
97 			tail = plan = new;
98 		} else {
99 			new = c_openparen(NULL, NULL, 0);
100 			new->next = plan;
101 			plan = new;
102 			new = c_closeparen(NULL, NULL, 0);
103 			tail->next = new;
104 			tail = new;
105 			new = c_print(NULL, NULL, 0);
106 			tail->next = new;
107 			tail = new;
108 		}
109 	}
110 
111 	/*
112 	 * the command line has been completely processed into a search plan
113 	 * except for the (, ), !, and -o operators.  Rearrange the plan so
114 	 * that the portions of the plan which are affected by the operators
115 	 * are moved into operator nodes themselves.  For example:
116 	 *
117 	 *	[!]--> [-name foo]--> [-print]
118 	 *
119 	 * becomes
120 	 *
121 	 *	[! [-name foo] ]--> [-print]
122 	 *
123 	 * and
124 	 *
125 	 *	[(]--> [-depth]--> [-name foo]--> [)]--> [-print]
126 	 *
127 	 * becomes
128 	 *
129 	 *	[expr [-depth]-->[-name foo] ]--> [-print]
130 	 *
131 	 * operators are handled in order of precedence.
132 	 */
133 
134 	plan = paren_squish(plan);		/* ()'s */
135 	plan = not_squish(plan);		/* !'s */
136 	plan = or_squish(plan);			/* -o's */
137 	return (plan);
138 }
139 
140 FTS *tree;			/* pointer to top of FTS hierarchy */
141 
142 /*
143  * find_execute --
144  *	take a search plan and an array of search paths and executes the plan
145  *	over all FTSENT's returned for the given search paths.
146  */
147 
148 FTSENT *entry;			/* shared with SIGINFO handler */
149 
150 int
find_execute(PLAN * plan,char ** paths)151 find_execute(PLAN *plan,	/* search plan */
152     char **paths)		/* array of pathnames to traverse */
153 {
154 	sigset_t fullset, oset;
155 	int r, rval;
156 	PLAN *p;
157 
158 	if (mayexecve == 0) {
159 		if (isdelete) {
160 			if (pledge("stdio rpath cpath getpw", NULL) == -1)
161 				err(1, "pledge");
162 		} else {
163 			if (pledge("stdio rpath getpw", NULL) == -1)
164 				err(1, "pledge");
165 		}
166 	} else {
167 		if (isdelete) {
168 			if (pledge("stdio rpath cpath getpw proc exec", NULL)
169 			    == -1)
170 				err(1, "pledge");
171 		} else {
172 			if (pledge("stdio rpath getpw proc exec", NULL) == -1)
173 				err(1, "pledge");
174 		}
175 	}
176 
177 	rval = 0;
178 
179 	if (!(tree = fts_open(paths, ftsoptions, NULL)))
180 		err(1, "fts_open");
181 
182 	sigfillset(&fullset);
183 	for (;;) {
184 		(void)sigprocmask(SIG_BLOCK, &fullset, &oset);
185 		entry = fts_read(tree);
186 		(void)sigprocmask(SIG_SETMASK, &oset, NULL);
187 		if (entry == NULL) {
188 			if (errno)
189 				err(1, "fts_read");
190 			break;
191 		}
192 
193 		switch (entry->fts_info) {
194 		case FTS_D:
195 			if (isdepth)
196 				continue;
197 			break;
198 		case FTS_DP:
199 			if (!isdepth)
200 				continue;
201 			break;
202 		case FTS_DNR:
203 		case FTS_ERR:
204 		case FTS_NS:
205 			(void)fflush(stdout);
206 			warnc(entry->fts_errno, "%s", entry->fts_path);
207 			rval = 1;
208 			continue;
209 		}
210 #define	BADCH	" \t\n\\'\""
211 		if (isxargs && strpbrk(entry->fts_path, BADCH)) {
212 			(void)fflush(stdout);
213 			warnx("%s: illegal path", entry->fts_path);
214 			rval = 1;
215 			continue;
216 		}
217 
218 		/*
219 		 * Call all the functions in the execution plan until one is
220 		 * false or all have been executed.  This is where we do all
221 		 * the work specified by the user on the command line.
222 		 */
223 		for (p = plan; p && (p->eval)(p, entry); p = p->next)
224 		    ;
225 	}
226 	(void)fts_close(tree);
227 
228 	/*
229 	 * Cleanup any plans with leftover state.
230 	 * Keep the last non-zero return value.
231 	 */
232 	if ((r = find_traverse(plan, plan_cleanup, NULL)) != 0)
233 		rval = r;
234 	return (rval);
235 }
236 
237 /*
238  * find_traverse --
239  *	traverse the plan tree and execute func() on all plans.  This
240  *	does not evaluate each plan's eval() function; it is intended
241  *	for operations that must run on all plans, such as state
242  *	cleanup.
243  *
244  *	If any func() returns non-zero, then so will find_traverse().
245  */
246 int
find_traverse(PLAN * plan,int (* func)(PLAN *,void *),void * arg)247 find_traverse(PLAN *plan, int (*func)(PLAN *, void *), void *arg)
248 {
249 	PLAN *p;
250 	int r, rval;
251 
252 	rval = 0;
253 	for (p = plan; p; p = p->next) {
254 		if ((r = func(p, arg)) != 0)
255 			rval = r;
256 		if (p->type == N_EXPR || p->type == N_OR) {
257 			if (p->p_data[0])
258 				if ((r = find_traverse(p->p_data[0],
259 					    func, arg)) != 0)
260 					rval = r;
261 			if (p->p_data[1])
262 				if ((r = find_traverse(p->p_data[1],
263 					    func, arg)) != 0)
264 					rval = r;
265 		}
266 	}
267 	return rval;
268 }
269