1 /*
2 * Copyright (c) 2014, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm_io.h"
27 #include "utilities/debug.hpp"
28 #include "utilities/stringUtils.hpp"
29
30 #include <ctype.h>
31 #include <string.h>
32
33 int StringUtils::replace_no_expand(char* string, const char* from, const char* to) {
34 int replace_count = 0;
35 size_t from_len = strlen(from);
36 size_t to_len = strlen(to);
37 assert(from_len >= to_len, "must not expand input");
38
39 for (char* dst = string; *dst && (dst = strstr(dst, from)) != nullptr;) {
40 char* left_over = dst + from_len;
41 memmove(dst, to, to_len); // does not copy trailing 0 of <to>
42 dst += to_len; // skip over the replacement.
43 memmove(dst, left_over, strlen(left_over) + 1); // copies the trailing 0 of <left_over>
44 ++ replace_count;
45 }
46
47 return replace_count;
48 }
49
50 double StringUtils::similarity(const char* str1, size_t len1, const char* str2, size_t len2) {
51 assert(str1 != nullptr && str2 != nullptr, "sanity");
52
53 // filter out zero-length strings else we will underflow on len-1 below
54 if (len1 == 0 || len2 == 0) {
55 return 0.0;
56 }
57
58 size_t total = len1 + len2;
59 size_t hit = 0;
60
61 for (size_t i = 0; i < len1 - 1; i++) {
62 for (size_t j = 0; j < len2 - 1; j++) {
63 if ((str1[i] == str2[j]) && (str1[i+1] == str2[j+1])) {
64 ++hit;
65 break;
66 }
67 }
68 }
69
70 return 2.0 * (double) hit / (double) total;
71 }
72
73 const char* StringUtils::strstr_nocase(const char* haystack, const char* needle) {
74 if (needle[0] == '\0') {
75 return haystack; // empty needle matches with anything
76 }
77 for (size_t i = 0; haystack[i] != '\0'; i++) {
78 bool matches = true;
79 for (size_t j = 0; needle[j] != '\0'; j++) {
80 if (haystack[i + j] == '\0') {
81 return nullptr; // hit end of haystack, abort
82 }
83 if (tolower(haystack[i + j]) != tolower(needle[j])) {
84 matches = false;
85 break; // abort, try next i
86 }
87 }
88 if (matches) {
89 return &haystack[i]; // all j were ok for this i
90 }
91 }
92 return nullptr; // no i was a match
93 }
94
95 bool StringUtils::is_star_match(const char* star_pattern, const char* str) {
96 const int N = 1000;
97 char pattern[N]; // copy pattern into this to ensure null termination
98 jio_snprintf(pattern, N, "%s", star_pattern);// ensures null termination
99 char buf[N]; // copy parts of pattern into this
100 const char* str_idx = str;
101 const char* pattern_idx = pattern;
102 while (strlen(pattern_idx) > 0) {
103 // find next section in pattern
104 const char* pattern_part_end = strstr(pattern_idx, "*");
105 const char* pattern_part = pattern_idx;
106 if (pattern_part_end != nullptr) { // copy part into buffer
107 size_t pattern_part_len = pattern_part_end-pattern_part;
108 strncpy(buf, pattern_part, pattern_part_len);
109 buf[pattern_part_len] = '\0'; // end of string
110 pattern_part = buf;
111 }
112 // find this section in s, case insensitive
113 const char* str_match = strstr_nocase(str_idx, pattern_part);
114 if (str_match == nullptr) {
115 return false; // r_part did not match - abort
116 }
117 size_t match_len = strlen(pattern_part);
118 // advance to match position plus part length
119 str_idx = str_match + match_len;
120 // advance by part length and "*"
121 pattern_idx += match_len + (pattern_part_end == nullptr ? 0 : 1);
122 }
123 return true; // all parts of pattern matched
124 }