138 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements the StringExtras.h header10//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 18using namespace llvm;19 20/// StrInStrNoCase - Portable version of strcasestr. Locates the first21/// occurrence of string 's1' in string 's2', ignoring case. Returns22/// the offset of s2 in s1 or npos if s2 cannot be found.23StringRef::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 any34/// leading characters that appear in the Delimiters string, and ending the35/// token at any of the characters that appear in the Delimiters string. If36/// there are no tokens in the source string, an empty string is returned.37/// The function returns a pair containing the extracted token and the38/// remaining tail string.39std::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 {Source.slice(Start, End), Source.substr(End)};48}49 50/// SplitString - Split up the specified string according to the specified51/// delimiters, appending the result fragments to the output list.52void 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 62void llvm::printEscapedString(StringRef Name, raw_ostream &Out) {63 for (unsigned char C : Name) {64 if (C == '\\')65 Out << '\\' << C;66 else if (isPrint(C) && C != '"')67 Out << C;68 else69 Out << '\\' << hexdigit(C >> 4) << hexdigit(C & 0x0F);70 }71}72 73void llvm::printHTMLEscaped(StringRef String, raw_ostream &Out) {74 for (char C : String) {75 if (C == '&')76 Out << "&";77 else if (C == '<')78 Out << "<";79 else if (C == '>')80 Out << ">";81 else if (C == '\"')82 Out << """;83 else if (C == '\'')84 Out << "'";85 else86 Out << C;87 }88}89 90void llvm::printLowerCase(StringRef String, raw_ostream &Out) {91 for (const char C : String)92 Out << toLower(C);93}94 95std::string llvm::convertToSnakeFromCamelCase(StringRef input) {96 if (input.empty())97 return "";98 99 std::string snakeCase;100 snakeCase.reserve(input.size());101 auto check = [&input](size_t j, function_ref<bool(int)> predicate) {102 return j < input.size() && predicate(input[j]);103 };104 for (size_t i = 0; i < input.size(); ++i) {105 snakeCase.push_back(tolower(input[i]));106 // Handles "runs" of capitals, such as in OPName -> op_name.107 if (check(i, isupper) && check(i + 1, isupper) && check(i + 2, islower))108 snakeCase.push_back('_');109 if ((check(i, islower) || check(i, isdigit)) && check(i + 1, isupper))110 snakeCase.push_back('_');111 }112 return snakeCase;113}114 115std::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 else127 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 else134 output.push_back(input[pos]);135 }136 return output;137}138