1 //===-- StringExtras.cpp - Implement the StringExtras header --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements the StringExtras.h header
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "llvm/ADT/StringExtras.h"
14 #include "llvm/ADT/SmallVector.h"
15 #include "llvm/Support/raw_ostream.h"
16 #include <cctype>
17
18 using namespace llvm;
19
20 /// StrInStrNoCase - Portable version of strcasestr. Locates the first
21 /// occurrence of string 's1' in string 's2', ignoring case. Returns
22 /// the offset of s2 in s1 or npos if s2 cannot be found.
StrInStrNoCase(StringRef s1,StringRef s2)23 StringRef::size_type llvm::StrInStrNoCase(StringRef s1, StringRef s2) {
24 size_t N = s2.size(), M = s1.size();
25 if (N > M)
26 return StringRef::npos;
27 for (size_t i = 0, e = M - N + 1; i != e; ++i)
28 if (s1.substr(i, N).equals_insensitive(s2))
29 return i;
30 return StringRef::npos;
31 }
32
33 /// getToken - This function extracts one token from source, ignoring any
34 /// leading characters that appear in the Delimiters string, and ending the
35 /// token at any of the characters that appear in the Delimiters string. If
36 /// there are no tokens in the source string, an empty string is returned.
37 /// The function returns a pair containing the extracted token and the
38 /// remaining tail string.
getToken(StringRef Source,StringRef Delimiters)39 std::pair<StringRef, StringRef> llvm::getToken(StringRef Source,
40 StringRef Delimiters) {
41 // Figure out where the token starts.
42 StringRef::size_type Start = Source.find_first_not_of(Delimiters);
43
44 // Find the next occurrence of the delimiter.
45 StringRef::size_type End = Source.find_first_of(Delimiters, Start);
46
47 return std::make_pair(Source.slice(Start, End), Source.substr(End));
48 }
49
50 /// SplitString - Split up the specified string according to the specified
51 /// delimiters, appending the result fragments to the output list.
SplitString(StringRef Source,SmallVectorImpl<StringRef> & OutFragments,StringRef Delimiters)52 void llvm::SplitString(StringRef Source,
53 SmallVectorImpl<StringRef> &OutFragments,
54 StringRef Delimiters) {
55 std::pair<StringRef, StringRef> S = getToken(Source, Delimiters);
56 while (!S.first.empty()) {
57 OutFragments.push_back(S.first);
58 S = getToken(S.second, Delimiters);
59 }
60 }
61
printEscapedString(StringRef Name,raw_ostream & Out)62 void llvm::printEscapedString(StringRef Name, raw_ostream &Out) {
63 for (unsigned i = 0, e = Name.size(); i != e; ++i) {
64 unsigned char C = Name[i];
65 if (C == '\\')
66 Out << '\\' << C;
67 else if (isPrint(C) && C != '"')
68 Out << C;
69 else
70 Out << '\\' << hexdigit(C >> 4) << hexdigit(C & 0x0F);
71 }
72 }
73
printHTMLEscaped(StringRef String,raw_ostream & Out)74 void llvm::printHTMLEscaped(StringRef String, raw_ostream &Out) {
75 for (char C : String) {
76 if (C == '&')
77 Out << "&";
78 else if (C == '<')
79 Out << "<";
80 else if (C == '>')
81 Out << ">";
82 else if (C == '\"')
83 Out << """;
84 else if (C == '\'')
85 Out << "'";
86 else
87 Out << C;
88 }
89 }
90
printLowerCase(StringRef String,raw_ostream & Out)91 void llvm::printLowerCase(StringRef String, raw_ostream &Out) {
92 for (const char C : String)
93 Out << toLower(C);
94 }
95
convertToSnakeFromCamelCase(StringRef input)96 std::string llvm::convertToSnakeFromCamelCase(StringRef input) {
97 if (input.empty())
98 return "";
99
100 std::string snakeCase;
101 snakeCase.reserve(input.size());
102 for (char c : input) {
103 if (!std::isupper(c)) {
104 snakeCase.push_back(c);
105 continue;
106 }
107
108 if (!snakeCase.empty() && snakeCase.back() != '_')
109 snakeCase.push_back('_');
110 snakeCase.push_back(llvm::toLower(c));
111 }
112 return snakeCase;
113 }
114
convertToCamelFromSnakeCase(StringRef input,bool capitalizeFirst)115 std::string llvm::convertToCamelFromSnakeCase(StringRef input,
116 bool capitalizeFirst) {
117 if (input.empty())
118 return "";
119
120 std::string output;
121 output.reserve(input.size());
122
123 // Push the first character, capatilizing if necessary.
124 if (capitalizeFirst && std::islower(input.front()))
125 output.push_back(llvm::toUpper(input.front()));
126 else
127 output.push_back(input.front());
128
129 // Walk the input converting any `*_[a-z]` snake case into `*[A-Z]` camelCase.
130 for (size_t pos = 1, e = input.size(); pos < e; ++pos) {
131 if (input[pos] == '_' && pos != (e - 1) && std::islower(input[pos + 1]))
132 output.push_back(llvm::toUpper(input[++pos]));
133 else
134 output.push_back(input[pos]);
135 }
136 return output;
137 }
138