busybox/shell/match.c

/*
 * ##/%% variable matching code ripped out of ash shell for code sharing
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
 *
 * Copyright (c) 1989, 1991, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * Copyright (c) 1997-2005 Herbert Xu <herbert@gondor.apana.org.au>
 * was re-ported from NetBSD and debianized.
 */
#ifdef STANDALONE
# include <stdbool.h>
# include <stdio.h>
# include <stdlib.h>
# include <string.h>
# include <unistd.h>
#else
# include "libbb.h"
#endif
#include <fnmatch.h>
#include "match.h"

#define pmatch(a, b) !fnmatch((a), (b), 0)

char *scanleft(char *string, char *pattern, bool match_at_left)
{
	char c;
	char *loc = string;

	do {
		int match;
		const char *s;

		c = *loc;
		if (match_at_left) {
			*loc = '\0';
			s = string;
		} else
			s = loc;
		match = pmatch(pattern, s);
		*loc = c;

		if (match)
			return loc;

		loc++;
	} while (c);

	return NULL;
}

char *scanright(char *string, char *pattern, bool match_at_left)
{
	char c;
	char *loc = string + strlen(string);

	while (loc >= string) {
		int match;
		const char *s;

		c = *loc;
		if (match_at_left) {
			*loc = '\0';
			s = string;
		} else
			s = loc;
		match = pmatch(pattern, s);
		*loc = c;

		if (match)
			return loc;

		loc--;
	}

	return NULL;
}

#ifdef STANDALONE
int main(int argc, char *argv[])
{
	char *string;
	char *op;
	char *pattern;
	bool match_at_left;
	char *loc;

	int i;

	if (argc == 1) {
		puts(
			"Usage: match <test> [test...]\n\n"
			"Where a <test> is the form: <string><op><match>\n"
			"This is to test the shell ${var#val} expression type.\n\n"
			"e.g. `match 'abc#a*'` -> bc"
		);
		return 1;
	}

	for (i = 1; i < argc; ++i) {
		size_t off;
		scan_t scan;

		printf("'%s': ", argv[i]);

		string = strdup(argv[i]);
		off = strcspn(string, "#%");
		if (!off) {
			printf("invalid format\n");
			free(string);
			continue;
		}
		op = string + off;
		scan = pick_scan(op[0], op[1], &match_at_left);
		pattern = op + 1;
		if (op[0] == op[1])
			op[1] = '\0', ++pattern;
		op[0] = '\0';

		loc = scan(string, pattern, match_at_left);

		if (match_at_left) {
			printf("'%s'\n", loc);
		} else {
			*loc = '\0';
			printf("'%s'\n", string);
		}

		free(string);
	}

	return 0;
}
#endif
1	/*
2	* ##/%% variable matching code ripped out of ash shell for code sharing
3	*
4	* This code is derived from software contributed to Berkeley by
5	* Kenneth Almquist.
6	*
7	* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
8	*
9	* Copyright (c) 1989, 1991, 1993, 1994
10	* The Regents of the University of California. All rights reserved.
11	*
12	* Copyright (c) 1997-2005 Herbert Xu <herbert@gondor.apana.org.au>
13	* was re-ported from NetBSD and debianized.
14	*/
15	#ifdef STANDALONE
16	# include <stdbool.h>
17	# include <stdio.h>
18	# include <stdlib.h>
19	# include <string.h>
20	# include <unistd.h>
21	#else
22	# include "libbb.h"
23	#endif
24	#include <fnmatch.h>
25	#include "match.h"
26
27	#define pmatch(a, b) !fnmatch((a), (b), 0)
28
29	char scanleft(char string, char *pattern, bool match_at_left)
30	{
31	char c;
32	char *loc = string;
33
34	do {
35	int match;
36	const char *s;
37
38	c = *loc;
39	if (match_at_left) {
40	*loc = '\0';
41	s = string;
42	} else
43	s = loc;
44	match = pmatch(pattern, s);
45	*loc = c;
46
47	if (match)
48	return loc;
49
50	loc++;
51	} while (c);
52
53	return NULL;
54	}
55
56	char scanright(char string, char *pattern, bool match_at_left)
57	{
58	char c;
59	char *loc = string + strlen(string);
60
61	while (loc >= string) {
62	int match;
63	const char *s;
64
65	c = *loc;
66	if (match_at_left) {
67	*loc = '\0';
68	s = string;
69	} else
70	s = loc;
71	match = pmatch(pattern, s);
72	*loc = c;
73
74	if (match)
75	return loc;
76
77	loc--;
78	}
79
80	return NULL;
81	}
82
83	#ifdef STANDALONE
84	int main(int argc, char *argv[])
85	{
86	char *string;
87	char *op;
88	char *pattern;
89	bool match_at_left;
90	char *loc;
91
92	int i;
93
94	if (argc == 1) {
95	puts(
96	"Usage: match <test> [test...]\n\n"
97	"Where a <test> is the form: <string><op><match>\n"
98	"This is to test the shell ${var#val} expression type.\n\n"
99	"e.g. `match 'abc#a*'` -> bc"
100	);
101	return 1;
102	}
103
104	for (i = 1; i < argc; ++i) {
105	size_t off;
106	scan_t scan;
107
108	printf("'%s': ", argv[i]);
109
110	string = strdup(argv[i]);
111	off = strcspn(string, "#%");
112	if (!off) {
113	printf("invalid format\n");
114	free(string);
115	continue;
116	}
117	op = string + off;
118	scan = pick_scan(op[0], op[1], &match_at_left);
119	pattern = op + 1;
120	if (op[0] == op[1])
121	op[1] = '\0', ++pattern;
122	op[0] = '\0';
123
124	loc = scan(string, pattern, match_at_left);
125
126	if (match_at_left) {
127	printf("'%s'\n", loc);
128	} else {
129	*loc = '\0';
130	printf("'%s'\n", string);
131	}
132
133	free(string);
134	}
135
136	return 0;
137	}
138	#endif