Bug Summary

File:src/usr.bin/find/find.c
Warning:line 107, column 4
Value stored to 'tail' is never read

Annotated Source Code

Press '?' to see keyboard shortcuts

clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name find.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 1 -pic-is-pie -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -target-feature +retpoline-indirect-calls -target-feature +retpoline-indirect-branches -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/usr.bin/find/obj -resource-dir /usr/local/lib/clang/13.0.0 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -fdebug-compilation-dir=/usr/src/usr.bin/find/obj -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c /usr/src/usr.bin/find/find.c
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(*__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
47int 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 */
56PLAN *
57find_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((void *)0); *argv;) {
78 if (!(new = find_create(&argv)))
79 continue;
80 if (plan == NULL((void *)0))
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((void *)0)) {
96 new = c_print(NULL((void *)0), NULL((void *)0), 0);
97 tail = plan = new;
98 } else {
99 new = c_openparen(NULL((void *)0), NULL((void *)0), 0);
100 new->next = plan;
101 plan = new;
102 new = c_closeparen(NULL((void *)0), NULL((void *)0), 0);
103 tail->next = new;
104 tail = new;
105 new = c_print(NULL((void *)0), NULL((void *)0), 0);
106 tail->next = new;
107 tail = new;
Value stored to 'tail' is never read
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
140FTS *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
148FTSENT *entry; /* shared with SIGINFO handler */
149
150int
151find_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((void *)0)) == -1)
161 err(1, "pledge");
162 } else {
163 if (pledge("stdio rpath getpw", NULL((void *)0)) == -1)
164 err(1, "pledge");
165 }
166 } else {
167 if (isdelete) {
168 if (pledge("stdio rpath cpath getpw proc exec", NULL((void *)0))
169 == -1)
170 err(1, "pledge");
171 } else {
172 if (pledge("stdio rpath getpw proc exec", NULL((void *)0)) == -1)
173 err(1, "pledge");
174 }
175 }
176
177 rval = 0;
178
179 if (!(tree = fts_open(paths, ftsoptions, NULL((void *)0))))
180 err(1, "fts_open");
181
182 sigfillset(&fullset);
183 for (;;) {
184 (void)sigprocmask(SIG_BLOCK1, &fullset, &oset);
185 entry = fts_read(tree);
186 (void)sigprocmask(SIG_SETMASK3, &oset, NULL((void *)0));
187 if (entry == NULL((void *)0)) {
188 if (errno(*__errno()))
189 err(1, "fts_read");
190 break;
191 }
192
193 switch (entry->fts_info) {
194 case FTS_D1:
195 if (isdepth)
196 continue;
197 break;
198 case FTS_DP6:
199 if (!isdepth)
200 continue;
201 break;
202 case FTS_DNR4:
203 case FTS_ERR7:
204 case FTS_NS10:
205 (void)fflush(stdout(&__sF[1]));
206 warnc(entry->fts_errno, "%s", entry->fts_path);
207 rval = 1;
208 continue;
209 }
210#define BADCH" \t\n\\'\"" " \t\n\\'\""
211 if (isxargs && strpbrk(entry->fts_path, BADCH" \t\n\\'\"")) {
212 (void)fflush(stdout(&__sF[1]));
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((void *)0))) != 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 */
246int
247find_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_datap_un._p_data[0])
258 if ((r = find_traverse(p->p_datap_un._p_data[0],
259 func, arg)) != 0)
260 rval = r;
261 if (p->p_datap_un._p_data[1])
262 if ((r = find_traverse(p->p_datap_un._p_data[1],
263 func, arg)) != 0)
264 rval = r;
265 }
266 }
267 return rval;
268}