1 //
2 // Copyright 2017 The Abseil Authors.
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 // https://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16 // -----------------------------------------------------------------------------
17 // File: match.h
18 // -----------------------------------------------------------------------------
19 //
20 // This file contains simple utilities for performing string matching checks.
21 // All of these function parameters are specified as `absl::string_view`,
22 // meaning that these functions can accept `std::string`, `absl::string_view` or
23 // NUL-terminated C-style strings.
24 //
25 // Examples:
26 // std::string s = "foo";
27 // absl::string_view sv = "f";
28 // assert(absl::StrContains(s, sv));
29 //
30 // Note: The order of parameters in these functions is designed to mimic the
31 // order an equivalent member function would exhibit;
32 // e.g. `s.Contains(x)` ==> `absl::StrContains(s, x).
33 #ifndef ABSL_STRINGS_MATCH_H_
34 #define ABSL_STRINGS_MATCH_H_
35
36 #include <cstring>
37
38 #include "absl/strings/string_view.h"
39
40 namespace absl {
41 ABSL_NAMESPACE_BEGIN
42
43 // StrContains()
44 //
45 // Returns whether a given string `haystack` contains the substring `needle`.
StrContains(absl::string_view haystack,absl::string_view needle)46 inline bool StrContains(absl::string_view haystack, absl::string_view needle) {
47 return haystack.find(needle, 0) != haystack.npos;
48 }
49
50 // StartsWith()
51 //
52 // Returns whether a given string `text` begins with `prefix`.
StartsWith(absl::string_view text,absl::string_view prefix)53 inline bool StartsWith(absl::string_view text, absl::string_view prefix) {
54 return prefix.empty() ||
55 (text.size() >= prefix.size() &&
56 memcmp(text.data(), prefix.data(), prefix.size()) == 0);
57 }
58
59 // EndsWith()
60 //
61 // Returns whether a given string `text` ends with `suffix`.
EndsWith(absl::string_view text,absl::string_view suffix)62 inline bool EndsWith(absl::string_view text, absl::string_view suffix) {
63 return suffix.empty() ||
64 (text.size() >= suffix.size() &&
65 memcmp(text.data() + (text.size() - suffix.size()), suffix.data(),
66 suffix.size()) == 0);
67 }
68
69 // EqualsIgnoreCase()
70 //
71 // Returns whether given ASCII strings `piece1` and `piece2` are equal, ignoring
72 // case in the comparison.
73 bool EqualsIgnoreCase(absl::string_view piece1, absl::string_view piece2);
74
75 // StartsWithIgnoreCase()
76 //
77 // Returns whether a given ASCII string `text` starts with `prefix`,
78 // ignoring case in the comparison.
79 bool StartsWithIgnoreCase(absl::string_view text, absl::string_view prefix);
80
81 // EndsWithIgnoreCase()
82 //
83 // Returns whether a given ASCII string `text` ends with `suffix`, ignoring
84 // case in the comparison.
85 bool EndsWithIgnoreCase(absl::string_view text, absl::string_view suffix);
86
87 ABSL_NAMESPACE_END
88 } // namespace absl
89
90 #endif // ABSL_STRINGS_MATCH_H_
91