xref: /netbsd-src/usr.bin/xlint/lint1/ckgetopt.c (revision d7b3b0431942747a82214a2bcb5f237506d570fe)
1 /* $NetBSD: ckgetopt.c,v 1.27 2024/03/19 23:19:03 rillig Exp $ */
2 
3 /*-
4  * Copyright (c) 2021 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Roland Illig <rillig@NetBSD.org>.
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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #if HAVE_NBTOOL_CONFIG_H
33 #include "nbtool_config.h"
34 #endif
35 
36 #include <sys/cdefs.h>
37 #if defined(__RCSID)
38 __RCSID("$NetBSD: ckgetopt.c,v 1.27 2024/03/19 23:19:03 rillig Exp $");
39 #endif
40 
41 #include <stdbool.h>
42 #include <stdlib.h>
43 #include <string.h>
44 
45 #include "lint1.h"
46 
47 /*
48  * In a typical while loop for parsing getopt options, ensure that each
49  * option from the options string is handled, and that each handled option
50  * is listed in the options string.
51  */
52 
53 static struct {
54 	/*-
55 	 * 0	means outside a while loop with a getopt call.
56 	 * 1	means directly inside a while loop with a getopt call.
57 	 * > 1	means in a nested while loop; this is used for finishing the
58 	 *	check at the correct point.
59 	 */
60 	int while_level;
61 
62 	/*
63 	 * The options string from the getopt call.  Whenever an option is
64 	 * handled by a case label, it is set to ' '.  In the end, only ' ' and
65 	 * ':' should remain.
66 	 */
67 	pos_t options_pos;
68 	char *options;
69 
70 	/*
71 	 * The nesting level of switch statements, is only modified if
72 	 * while_level > 0.  Only the case labels at switch_level == 1 are
73 	 * relevant, all nested case labels are ignored.
74 	 */
75 	int switch_level;
76 } ck;
77 
78 /* Return whether tn has the form '(c = getopt(argc, argv, "str")) != -1'. */
79 static bool
is_getopt_condition(const tnode_t * tn,char ** out_options)80 is_getopt_condition(const tnode_t *tn, char **out_options)
81 {
82 	const function_call *call;
83 	const tnode_t *last_arg;
84 	const buffer *str;
85 
86 	if (tn != NULL
87 	    && tn->tn_op == NE
88 
89 	    && tn->u.ops.right->tn_op == CON
90 	    && tn->u.ops.right->u.value.v_tspec == INT
91 	    && tn->u.ops.right->u.value.u.integer == -1
92 
93 	    && tn->u.ops.left->tn_op == ASSIGN
94 	    && tn->u.ops.left->u.ops.right->tn_op == CALL
95 	    && (call = tn->u.ops.left->u.ops.right->u.call)->func->tn_op == ADDR
96 	    && call->func->u.ops.left->tn_op == NAME
97 	    && strcmp(call->func->u.ops.left->u.sym->s_name, "getopt") == 0
98 	    && call->args_len == 3
99 	    && (last_arg = call->args[2]) != NULL
100 	    && last_arg->tn_op == CVT
101 	    && last_arg->u.ops.left->tn_op == ADDR
102 	    && last_arg->u.ops.left->u.ops.left->tn_op == STRING
103 	    && (str = last_arg->u.ops.left->u.ops.left->u.str_literals)->data != NULL) {
104 		buffer buf;
105 		buf_init(&buf);
106 		quoted_iterator it = { .end = 0 };
107 		while (quoted_next(str, &it))
108 			buf_add_char(&buf, (char)it.value);
109 		*out_options = buf.data;
110 		return true;
111 	}
112 	return false;
113 }
114 
115 static void
check_unlisted_option(char opt)116 check_unlisted_option(char opt)
117 {
118 	if (opt == ':' && ck.options[0] != ':')
119 		goto warn;
120 
121 	char *optptr = strchr(ck.options, opt);
122 	if (optptr != NULL)
123 		*optptr = ' ';
124 	else if (opt != '?')
125 	warn:
126 		/* option '%c' should be listed in the options string */
127 		warning(339, opt);
128 }
129 
130 static void
check_unhandled_option(void)131 check_unhandled_option(void)
132 {
133 	for (const char *opt = ck.options; *opt != '\0'; opt++) {
134 		if (*opt == ' ' || *opt == ':')
135 			continue;
136 
137 		/* option '%c' should be handled in the switch */
138 		warning_at(338, &ck.options_pos, *opt);
139 	}
140 }
141 
142 
143 void
check_getopt_begin_while(const tnode_t * tn)144 check_getopt_begin_while(const tnode_t *tn)
145 {
146 	if (ck.while_level == 0) {
147 		if (!is_getopt_condition(tn, &ck.options))
148 			return;
149 		ck.options_pos = curr_pos;
150 	}
151 	ck.while_level++;
152 }
153 
154 void
check_getopt_begin_switch(void)155 check_getopt_begin_switch(void)
156 {
157 	if (ck.while_level > 0)
158 		ck.switch_level++;
159 }
160 
161 void
check_getopt_case_label(int64_t value)162 check_getopt_case_label(int64_t value)
163 {
164 	if (ck.switch_level == 1 && value == (char)value)
165 		check_unlisted_option((char)value);
166 }
167 
168 void
check_getopt_end_switch(void)169 check_getopt_end_switch(void)
170 {
171 	if (ck.switch_level == 0)
172 		return;
173 
174 	ck.switch_level--;
175 	if (ck.switch_level == 0)
176 		check_unhandled_option();
177 }
178 
179 void
check_getopt_end_while(void)180 check_getopt_end_while(void)
181 {
182 	if (ck.while_level == 0)
183 		return;
184 
185 	ck.while_level--;
186 	if (ck.while_level != 0)
187 		return;
188 
189 	free(ck.options);
190 	ck.options = NULL;
191 }
192