xref: /openbsd/usr.bin/find/find.c (revision cca36db2)
1 /*	$OpenBSD: find.c,v 1.16 2012/01/02 23:19:45 pascal 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 
46 #include "find.h"
47 
48 /*
49  * find_formplan --
50  *	process the command line and create a "plan" corresponding to the
51  *	command arguments.
52  */
53 PLAN *
54 find_formplan(char **argv)
55 {
56 	PLAN *plan, *tail, *new;
57 
58 	/*
59 	 * for each argument in the command line, determine what kind of node
60 	 * it is, create the appropriate node type and add the new plan node
61 	 * to the end of the existing plan.  The resulting plan is a linked
62 	 * list of plan nodes.  For example, the string:
63 	 *
64 	 *	% find . -name foo -newer bar -print
65 	 *
66 	 * results in the plan:
67 	 *
68 	 *	[-name foo]--> [-newer bar]--> [-print]
69 	 *
70 	 * in this diagram, `[-name foo]' represents the plan node generated
71 	 * by c_name() with an argument of foo and `-->' represents the
72 	 * plan->next pointer.
73 	 */
74 	for (plan = tail = NULL; *argv;) {
75 		if (!(new = find_create(&argv)))
76 			continue;
77 		if (plan == NULL)
78 			tail = plan = new;
79 		else {
80 			tail->next = new;
81 			tail = new;
82 		}
83 	}
84 
85 	/*
86 	 * if the user didn't specify one of -print, -ok or -exec, then -print
87 	 * is assumed so we bracket the current expression with parens, if
88 	 * necessary, and add a -print node on the end.
89 	 */
90 	if (!isoutput) {
91 		if (plan == NULL) {
92 			new = c_print(NULL, NULL, 0);
93 			tail = plan = new;
94 		} else {
95 			new = c_openparen(NULL, NULL, 0);
96 			new->next = plan;
97 			plan = new;
98 			new = c_closeparen(NULL, NULL, 0);
99 			tail->next = new;
100 			tail = new;
101 			new = c_print(NULL, NULL, 0);
102 			tail->next = new;
103 			tail = new;
104 		}
105 	}
106 
107 	/*
108 	 * the command line has been completely processed into a search plan
109 	 * except for the (, ), !, and -o operators.  Rearrange the plan so
110 	 * that the portions of the plan which are affected by the operators
111 	 * are moved into operator nodes themselves.  For example:
112 	 *
113 	 *	[!]--> [-name foo]--> [-print]
114 	 *
115 	 * becomes
116 	 *
117 	 *	[! [-name foo] ]--> [-print]
118 	 *
119 	 * and
120 	 *
121 	 *	[(]--> [-depth]--> [-name foo]--> [)]--> [-print]
122 	 *
123 	 * becomes
124 	 *
125 	 *	[expr [-depth]-->[-name foo] ]--> [-print]
126 	 *
127 	 * operators are handled in order of precedence.
128 	 */
129 
130 	plan = paren_squish(plan);		/* ()'s */
131 	plan = not_squish(plan);		/* !'s */
132 	plan = or_squish(plan);			/* -o's */
133 	return (plan);
134 }
135 
136 FTS *tree;			/* pointer to top of FTS hierarchy */
137 
138 /*
139  * find_execute --
140  *	take a search plan and an array of search paths and executes the plan
141  *	over all FTSENT's returned for the given search paths.
142  */
143 
144 FTSENT *entry;			/* shared with SIGINFO handler */
145 
146 int
147 find_execute(PLAN *plan,	/* search plan */
148     char **paths)		/* array of pathnames to traverse */
149 {
150 	sigset_t fullset, oset;
151 	int r, rval;
152 	PLAN *p;
153 
154 	rval = 0;
155 
156 	if (!(tree = fts_open(paths, ftsoptions, NULL)))
157 		err(1, "fts_open");
158 
159 	sigfillset(&fullset);
160 	for (;;) {
161 		(void)sigprocmask(SIG_BLOCK, &fullset, &oset);
162 		entry = fts_read(tree);
163 		(void)sigprocmask(SIG_SETMASK, &oset, NULL);
164 		if (entry == NULL) {
165 			if (errno)
166 				err(1, "fts_read");
167 			break;
168 		}
169 
170 		switch (entry->fts_info) {
171 		case FTS_D:
172 			if (isdepth)
173 				continue;
174 			break;
175 		case FTS_DP:
176 			if (!isdepth)
177 				continue;
178 			break;
179 		case FTS_DNR:
180 		case FTS_ERR:
181 		case FTS_NS:
182 			(void)fflush(stdout);
183 			warn("%s", entry->fts_path);
184 			rval = 1;
185 			continue;
186 		}
187 #define	BADCH	" \t\n\\'\""
188 		if (isxargs && strpbrk(entry->fts_path, BADCH)) {
189 			(void)fflush(stdout);
190 			warnx("%s: illegal path", entry->fts_path);
191 			rval = 1;
192 			continue;
193 		}
194 
195 		/*
196 		 * Call all the functions in the execution plan until one is
197 		 * false or all have been executed.  This is where we do all
198 		 * the work specified by the user on the command line.
199 		 */
200 		for (p = plan; p && (p->eval)(p, entry); p = p->next)
201 		    ;
202 	}
203 	(void)fts_close(tree);
204 
205 	/*
206 	 * Cleanup any plans with leftover state.
207 	 * Keep the last non-zero return value.
208 	 */
209 	if ((r = find_traverse(plan, plan_cleanup, NULL)) != 0)
210 		rval = r;
211 	return (rval);
212 }
213 
214 /*
215  * find_traverse --
216  *	traverse the plan tree and execute func() on all plans.  This
217  *	does not evaluate each plan's eval() function; it is intended
218  *	for operations that must run on all plans, such as state
219  *	cleanup.
220  *
221  *	If any func() returns non-zero, then so will find_traverse().
222  */
223 int
224 find_traverse(PLAN *plan, int (*func)(PLAN *, void *), void *arg)
225 {
226 	PLAN *p;
227 	int r, rval;
228 
229 	rval = 0;
230 	for (p = plan; p; p = p->next) {
231 		if ((r = func(p, arg)) != 0)
232 			rval = r;
233 		if (p->type == N_EXPR || p->type == N_OR) {
234 			if (p->p_data[0])
235 				if ((r = find_traverse(p->p_data[0],
236 					    func, arg)) != 0)
237 					rval = r;
238 			if (p->p_data[1])
239 				if ((r = find_traverse(p->p_data[1],
240 					    func, arg)) != 0)
241 					rval = r;
242 		}
243 	}
244 	return rval;
245 }
246