1//===-- llvm/ADT/StringExtras.h - Useful string functions -------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file contains some functions that are useful when dealing with strings. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef LLVM_ADT_STRINGEXTRAS_H 15#define LLVM_ADT_STRINGEXTRAS_H 16 17#include "llvm/Support/DataTypes.h" 18#include "llvm/ADT/APFloat.h" 19#include "llvm/ADT/DenseMapInfo.h" 20#include "llvm/ADT/StringRef.h" 21#include <cctype> 22#include <cstdio> 23#include <string> 24 25namespace llvm { 26template<typename T> class SmallVectorImpl; 27 28/// hexdigit - Return the hexadecimal character for the 29/// given number \arg X (which should be less than 16). 30static inline char hexdigit(unsigned X, bool LowerCase = false) { 31 const char HexChar = LowerCase ? 'a' : 'A'; 32 return X < 10 ? '0' + X : HexChar + X - 10; 33} 34 35/// utohex_buffer - Emit the specified number into the buffer specified by 36/// BufferEnd, returning a pointer to the start of the string. This can be used 37/// like this: (note that the buffer must be large enough to handle any number): 38/// char Buffer[40]; 39/// printf("0x%s", utohex_buffer(X, Buffer+40)); 40/// 41/// This should only be used with unsigned types. 42/// 43template<typename IntTy> 44static inline char *utohex_buffer(IntTy X, char *BufferEnd) { 45 char *BufPtr = BufferEnd; 46 *--BufPtr = 0; // Null terminate buffer. 47 if (X == 0) { 48 *--BufPtr = '0'; // Handle special case. 49 return BufPtr; 50 } 51 52 while (X) { 53 unsigned char Mod = static_cast<unsigned char>(X) & 15; 54 *--BufPtr = hexdigit(Mod); 55 X >>= 4; 56 } 57 return BufPtr; 58} 59 60static inline std::string utohexstr(uint64_t X) { 61 char Buffer[17]; 62 return utohex_buffer(X, Buffer+17); 63} 64 65static inline std::string utostr_32(uint32_t X, bool isNeg = false) { 66 char Buffer[11]; 67 char *BufPtr = Buffer+11; 68 69 if (X == 0) *--BufPtr = '0'; // Handle special case... 70 71 while (X) { 72 *--BufPtr = '0' + char(X % 10); 73 X /= 10; 74 } 75 76 if (isNeg) *--BufPtr = '-'; // Add negative sign... 77 78 return std::string(BufPtr, Buffer+11); 79} 80 81static inline std::string utostr(uint64_t X, bool isNeg = false) { 82 char Buffer[21]; 83 char *BufPtr = Buffer+21; 84 85 if (X == 0) *--BufPtr = '0'; // Handle special case... 86 87 while (X) { 88 *--BufPtr = '0' + char(X % 10); 89 X /= 10; 90 } 91 92 if (isNeg) *--BufPtr = '-'; // Add negative sign... 93 return std::string(BufPtr, Buffer+21); 94} 95 96 97static inline std::string itostr(int64_t X) { 98 if (X < 0) 99 return utostr(static_cast<uint64_t>(-X), true); 100 else 101 return utostr(static_cast<uint64_t>(X)); 102} 103 104static inline std::string ftostr(double V) { 105 char Buffer[200]; 106 sprintf(Buffer, "%20.6e", V); 107 char *B = Buffer; 108 while (*B == ' ') ++B; 109 return B; 110} 111 112static inline std::string ftostr(const APFloat& V) { 113 if (&V.getSemantics() == &APFloat::IEEEdouble) 114 return ftostr(V.convertToDouble()); 115 else if (&V.getSemantics() == &APFloat::IEEEsingle) 116 return ftostr((double)V.convertToFloat()); 117 return "<unknown format in ftostr>"; // error 118} 119 120static inline std::string LowercaseString(const std::string &S) { 121 std::string result(S); 122 for (unsigned i = 0; i < S.length(); ++i) 123 if (isupper(result[i])) 124 result[i] = char(tolower(result[i])); 125 return result; 126} 127 128static inline std::string UppercaseString(const std::string &S) { 129 std::string result(S); 130 for (unsigned i = 0; i < S.length(); ++i) 131 if (islower(result[i])) 132 result[i] = char(toupper(result[i])); 133 return result; 134} 135 136/// StrInStrNoCase - Portable version of strcasestr. Locates the first 137/// occurrence of string 's1' in string 's2', ignoring case. Returns 138/// the offset of s2 in s1 or npos if s2 cannot be found. 139StringRef::size_type StrInStrNoCase(StringRef s1, StringRef s2); 140 141/// getToken - This function extracts one token from source, ignoring any 142/// leading characters that appear in the Delimiters string, and ending the 143/// token at any of the characters that appear in the Delimiters string. If 144/// there are no tokens in the source string, an empty string is returned. 145/// The function returns a pair containing the extracted token and the 146/// remaining tail string. 147std::pair<StringRef, StringRef> getToken(StringRef Source, 148 StringRef Delimiters = " \t\n\v\f\r"); 149 150/// SplitString - Split up the specified string according to the specified 151/// delimiters, appending the result fragments to the output list. 152void SplitString(StringRef Source, 153 SmallVectorImpl<StringRef> &OutFragments, 154 StringRef Delimiters = " \t\n\v\f\r"); 155 156/// HashString - Hash function for strings. 157/// 158/// This is the Bernstein hash function. 159// 160// FIXME: Investigate whether a modified bernstein hash function performs 161// better: http://eternallyconfuzzled.com/tuts/algorithms/jsw_tut_hashing.aspx 162// X*33+c -> X*33^c 163static inline unsigned HashString(StringRef Str, unsigned Result = 0) { 164 for (unsigned i = 0, e = Str.size(); i != e; ++i) 165 Result = Result * 33 + Str[i]; 166 return Result; 167} 168 169} // End llvm namespace 170 171#endif 172