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 GPLv2 or later, see file LICENSE in this source tree.
|
---|
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 | # define FAST_FUNC /* nothing */
|
---|
22 | # define PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN /* nothing */
|
---|
23 | # define POP_SAVED_FUNCTION_VISIBILITY /* nothing */
|
---|
24 | #else
|
---|
25 | # include "libbb.h"
|
---|
26 | #endif
|
---|
27 | #include <fnmatch.h>
|
---|
28 | #include "match.h"
|
---|
29 |
|
---|
30 | char* FAST_FUNC scan_and_match(char *string, const char *pattern, unsigned flags)
|
---|
31 | {
|
---|
32 | char *loc;
|
---|
33 | char *end;
|
---|
34 | unsigned len = strlen(string);
|
---|
35 | int early_exit;
|
---|
36 |
|
---|
37 | /* We can stop the scan early only if the string part
|
---|
38 | * we are matching against is shrinking, and the pattern has
|
---|
39 | * an unquoted "star" at the corresponding end. There are two cases.
|
---|
40 | * Case 1:
|
---|
41 | * "qwerty" does not match against pattern "*zy",
|
---|
42 | * no point in trying to match "werty", "erty" etc:
|
---|
43 | */
|
---|
44 | early_exit = (flags == (SCAN_MOVE_FROM_LEFT + SCAN_MATCH_RIGHT_HALF) && pattern[0] == '*');
|
---|
45 |
|
---|
46 | if (flags & SCAN_MOVE_FROM_LEFT) {
|
---|
47 | loc = string;
|
---|
48 | end = string + len + 1;
|
---|
49 | } else {
|
---|
50 | loc = string + len;
|
---|
51 | end = string - 1;
|
---|
52 | if (flags == (SCAN_MOVE_FROM_RIGHT + SCAN_MATCH_LEFT_HALF)) {
|
---|
53 | /* Case 2:
|
---|
54 | * "qwerty" does not match against pattern "qz*",
|
---|
55 | * no point in trying to match "qwert", "qwer" etc:
|
---|
56 | */
|
---|
57 | const char *p = pattern + strlen(pattern);
|
---|
58 | if (--p >= pattern && *p == '*') {
|
---|
59 | early_exit = 1;
|
---|
60 | while (--p >= pattern && *p == '\\')
|
---|
61 | early_exit ^= 1;
|
---|
62 | }
|
---|
63 | }
|
---|
64 | }
|
---|
65 |
|
---|
66 | while (loc != end) {
|
---|
67 | char c;
|
---|
68 | int r;
|
---|
69 |
|
---|
70 | c = *loc;
|
---|
71 | if (flags & SCAN_MATCH_LEFT_HALF) {
|
---|
72 | *loc = '\0';
|
---|
73 | r = fnmatch(pattern, string, 0);
|
---|
74 | *loc = c;
|
---|
75 | } else {
|
---|
76 | r = fnmatch(pattern, loc, 0);
|
---|
77 | }
|
---|
78 | if (r == 0) /* match found */
|
---|
79 | return loc;
|
---|
80 | if (early_exit) {
|
---|
81 | #ifdef STANDALONE
|
---|
82 | printf("(early exit) ");
|
---|
83 | #endif
|
---|
84 | break;
|
---|
85 | }
|
---|
86 |
|
---|
87 | if (flags & SCAN_MOVE_FROM_LEFT) {
|
---|
88 | loc++;
|
---|
89 | } else {
|
---|
90 | loc--;
|
---|
91 | }
|
---|
92 | }
|
---|
93 | return NULL;
|
---|
94 | }
|
---|
95 |
|
---|
96 | #ifdef STANDALONE
|
---|
97 | int main(int argc, char *argv[])
|
---|
98 | {
|
---|
99 | char *string;
|
---|
100 | char *op;
|
---|
101 | char *pattern;
|
---|
102 | char *loc;
|
---|
103 |
|
---|
104 | setvbuf(stdout, NULL, _IONBF, 0);
|
---|
105 |
|
---|
106 | if (!argv[1]) {
|
---|
107 | puts(
|
---|
108 | "Usage: match <test> [test...]\n\n"
|
---|
109 | "Where a <test> is the form: <string><op><match>\n"
|
---|
110 | "This is to test the shell ${var#val} expression type.\n\n"
|
---|
111 | "e.g. `match 'abc#a*'` -> bc"
|
---|
112 | );
|
---|
113 | return 1;
|
---|
114 | }
|
---|
115 |
|
---|
116 | while (*++argv) {
|
---|
117 | size_t off;
|
---|
118 | unsigned scan_flags;
|
---|
119 |
|
---|
120 | string = *argv;
|
---|
121 | off = strcspn(string, "#%");
|
---|
122 | if (!off) {
|
---|
123 | printf("invalid format\n");
|
---|
124 | continue;
|
---|
125 | }
|
---|
126 | op = string + off;
|
---|
127 | scan_flags = pick_scan(op[0], op[1]);
|
---|
128 |
|
---|
129 | printf("'%s': flags:%x, ", string, scan_flags);
|
---|
130 | pattern = op + 1;
|
---|
131 | if (op[0] == op[1])
|
---|
132 | pattern++;
|
---|
133 | op[0] = '\0';
|
---|
134 |
|
---|
135 | loc = scan_and_match(string, pattern, scan_flags);
|
---|
136 |
|
---|
137 | if (scan_flags & SCAN_MATCH_LEFT_HALF) {
|
---|
138 | printf("'%s'\n", loc);
|
---|
139 | } else {
|
---|
140 | if (loc)
|
---|
141 | *loc = '\0';
|
---|
142 | printf("'%s'\n", string);
|
---|
143 | }
|
---|
144 | }
|
---|
145 |
|
---|
146 | return 0;
|
---|
147 | }
|
---|
148 | #endif
|
---|