| //===- llvm/ADT/StringExtras.h - Useful string functions --------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file contains some functions that are useful when dealing with strings. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_ADT_STRINGEXTRAS_H |
| #define LLVM_ADT_STRINGEXTRAS_H |
| |
| #include "llvm/ADT/ArrayRef.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/StringRef.h" |
| #include <cassert> |
| #include <cstddef> |
| #include <cstdint> |
| #include <cstdlib> |
| #include <cstring> |
| #include <iterator> |
| #include <string> |
| #include <utility> |
| |
| namespace llvm { |
| |
| template<typename T> class SmallVectorImpl; |
| class raw_ostream; |
| |
| /// hexdigit - Return the hexadecimal character for the |
| /// given number \p X (which should be less than 16). |
| static inline char hexdigit(unsigned X, bool LowerCase = false) { |
| const char HexChar = LowerCase ? 'a' : 'A'; |
| return X < 10 ? '0' + X : HexChar + X - 10; |
| } |
| |
| /// Construct a string ref from a boolean. |
| static inline StringRef toStringRef(bool B) { |
| return StringRef(B ? "true" : "false"); |
| } |
| |
| /// Construct a string ref from an array ref of unsigned chars. |
| static inline StringRef toStringRef(ArrayRef<uint8_t> Input) { |
| return StringRef(reinterpret_cast<const char *>(Input.begin()), Input.size()); |
| } |
| |
| /// Interpret the given character \p C as a hexadecimal digit and return its |
| /// value. |
| /// |
| /// If \p C is not a valid hex digit, -1U is returned. |
| static inline unsigned hexDigitValue(char C) { |
| if (C >= '0' && C <= '9') return C-'0'; |
| if (C >= 'a' && C <= 'f') return C-'a'+10U; |
| if (C >= 'A' && C <= 'F') return C-'A'+10U; |
| return -1U; |
| } |
| |
| /// Checks if character \p C is one of the 10 decimal digits. |
| static inline bool isDigit(char C) { return C >= '0' && C <= '9'; } |
| |
| /// Checks if character \p C is a hexadecimal numeric character. |
| static inline bool isHexDigit(char C) { return hexDigitValue(C) != -1U; } |
| |
| /// Checks if character \p C is a valid letter as classified by "C" locale. |
| static inline bool isAlpha(char C) { |
| return ('a' <= C && C <= 'z') || ('A' <= C && C <= 'Z'); |
| } |
| |
| /// Checks whether character \p C is either a decimal digit or an uppercase or |
| /// lowercase letter as classified by "C" locale. |
| static inline bool isAlnum(char C) { return isAlpha(C) || isDigit(C); } |
| |
| static inline std::string utohexstr(uint64_t X, bool LowerCase = false) { |
| char Buffer[17]; |
| char *BufPtr = std::end(Buffer); |
| |
| if (X == 0) *--BufPtr = '0'; |
| |
| while (X) { |
| unsigned char Mod = static_cast<unsigned char>(X) & 15; |
| *--BufPtr = hexdigit(Mod, LowerCase); |
| X >>= 4; |
| } |
| |
| return std::string(BufPtr, std::end(Buffer)); |
| } |
| |
| /// Convert buffer \p Input to its hexadecimal representation. |
| /// The returned string is double the size of \p Input. |
| inline std::string toHex(StringRef Input) { |
| static const char *const LUT = "0123456789ABCDEF"; |
| size_t Length = Input.size(); |
| |
| std::string Output; |
| Output.reserve(2 * Length); |
| for (size_t i = 0; i < Length; ++i) { |
| const unsigned char c = Input[i]; |
| Output.push_back(LUT[c >> 4]); |
| Output.push_back(LUT[c & 15]); |
| } |
| return Output; |
| } |
| |
| inline std::string toHex(ArrayRef<uint8_t> Input) { |
| return toHex(toStringRef(Input)); |
| } |
| |
| static inline uint8_t hexFromNibbles(char MSB, char LSB) { |
| unsigned U1 = hexDigitValue(MSB); |
| unsigned U2 = hexDigitValue(LSB); |
| assert(U1 != -1U && U2 != -1U); |
| |
| return static_cast<uint8_t>((U1 << 4) | U2); |
| } |
| |
| /// Convert hexadecimal string \p Input to its binary representation. |
| /// The return string is half the size of \p Input. |
| static inline std::string fromHex(StringRef Input) { |
| if (Input.empty()) |
| return std::string(); |
| |
| std::string Output; |
| Output.reserve((Input.size() + 1) / 2); |
| if (Input.size() % 2 == 1) { |
| Output.push_back(hexFromNibbles('0', Input.front())); |
| Input = Input.drop_front(); |
| } |
| |
| assert(Input.size() % 2 == 0); |
| while (!Input.empty()) { |
| uint8_t Hex = hexFromNibbles(Input[0], Input[1]); |
| Output.push_back(Hex); |
| Input = Input.drop_front(2); |
| } |
| return Output; |
| } |
| |
| /// \brief Convert the string \p S to an integer of the specified type using |
| /// the radix \p Base. If \p Base is 0, auto-detects the radix. |
| /// Returns true if the number was successfully converted, false otherwise. |
| template <typename N> bool to_integer(StringRef S, N &Num, unsigned Base = 0) { |
| return !S.getAsInteger(Base, Num); |
| } |
| |
| namespace detail { |
| template <typename N> |
| inline bool to_float(const Twine &T, N &Num, N (*StrTo)(const char *, char **)) { |
| SmallString<32> Storage; |
| StringRef S = T.toNullTerminatedStringRef(Storage); |
| char *End; |
| N Temp = StrTo(S.data(), &End); |
| if (*End != '\0') |
| return false; |
| Num = Temp; |
| return true; |
| } |
| } |
| |
| inline bool to_float(const Twine &T, float &Num) { |
| return detail::to_float(T, Num, strtof); |
| } |
| |
| inline bool to_float(const Twine &T, double &Num) { |
| return detail::to_float(T, Num, strtod); |
| } |
| |
| inline bool to_float(const Twine &T, long double &Num) { |
| return detail::to_float(T, Num, strtold); |
| } |
| |
| static inline std::string utostr(uint64_t X, bool isNeg = false) { |
| char Buffer[21]; |
| char *BufPtr = std::end(Buffer); |
| |
| if (X == 0) *--BufPtr = '0'; // Handle special case... |
| |
| while (X) { |
| *--BufPtr = '0' + char(X % 10); |
| X /= 10; |
| } |
| |
| if (isNeg) *--BufPtr = '-'; // Add negative sign... |
| return std::string(BufPtr, std::end(Buffer)); |
| } |
| |
| static inline std::string itostr(int64_t X) { |
| if (X < 0) |
| return utostr(static_cast<uint64_t>(-X), true); |
| else |
| return utostr(static_cast<uint64_t>(X)); |
| } |
| |
| /// StrInStrNoCase - Portable version of strcasestr. Locates the first |
| /// occurrence of string 's1' in string 's2', ignoring case. Returns |
| /// the offset of s2 in s1 or npos if s2 cannot be found. |
| StringRef::size_type StrInStrNoCase(StringRef s1, StringRef s2); |
| |
| /// getToken - This function extracts one token from source, ignoring any |
| /// leading characters that appear in the Delimiters string, and ending the |
| /// token at any of the characters that appear in the Delimiters string. If |
| /// there are no tokens in the source string, an empty string is returned. |
| /// The function returns a pair containing the extracted token and the |
| /// remaining tail string. |
| std::pair<StringRef, StringRef> getToken(StringRef Source, |
| StringRef Delimiters = " \t\n\v\f\r"); |
| |
| /// SplitString - Split up the specified string according to the specified |
| /// delimiters, appending the result fragments to the output list. |
| void SplitString(StringRef Source, |
| SmallVectorImpl<StringRef> &OutFragments, |
| StringRef Delimiters = " \t\n\v\f\r"); |
| |
| /// HashString - Hash function for strings. |
| /// |
| /// This is the Bernstein hash function. |
| // |
| // FIXME: Investigate whether a modified bernstein hash function performs |
| // better: http://eternallyconfuzzled.com/tuts/algorithms/jsw_tut_hashing.aspx |
| // X*33+c -> X*33^c |
| static inline unsigned HashString(StringRef Str, unsigned Result = 0) { |
| for (StringRef::size_type i = 0, e = Str.size(); i != e; ++i) |
| Result = Result * 33 + (unsigned char)Str[i]; |
| return Result; |
| } |
| |
| /// Returns the English suffix for an ordinal integer (-st, -nd, -rd, -th). |
| static inline StringRef getOrdinalSuffix(unsigned Val) { |
| // It is critically important that we do this perfectly for |
| // user-written sequences with over 100 elements. |
| switch (Val % 100) { |
| case 11: |
| case 12: |
| case 13: |
| return "th"; |
| default: |
| switch (Val % 10) { |
| case 1: return "st"; |
| case 2: return "nd"; |
| case 3: return "rd"; |
| default: return "th"; |
| } |
| } |
| } |
| |
| /// PrintEscapedString - Print each character of the specified string, escaping |
| /// it if it is not printable or if it is an escape char. |
| void PrintEscapedString(StringRef Name, raw_ostream &Out); |
| |
| namespace detail { |
| |
| template <typename IteratorT> |
| inline std::string join_impl(IteratorT Begin, IteratorT End, |
| StringRef Separator, std::input_iterator_tag) { |
| std::string S; |
| if (Begin == End) |
| return S; |
| |
| S += (*Begin); |
| while (++Begin != End) { |
| S += Separator; |
| S += (*Begin); |
| } |
| return S; |
| } |
| |
| template <typename IteratorT> |
| inline std::string join_impl(IteratorT Begin, IteratorT End, |
| StringRef Separator, std::forward_iterator_tag) { |
| std::string S; |
| if (Begin == End) |
| return S; |
| |
| size_t Len = (std::distance(Begin, End) - 1) * Separator.size(); |
| for (IteratorT I = Begin; I != End; ++I) |
| Len += (*Begin).size(); |
| S.reserve(Len); |
| S += (*Begin); |
| while (++Begin != End) { |
| S += Separator; |
| S += (*Begin); |
| } |
| return S; |
| } |
| |
| template <typename Sep> |
| inline void join_items_impl(std::string &Result, Sep Separator) {} |
| |
| template <typename Sep, typename Arg> |
| inline void join_items_impl(std::string &Result, Sep Separator, |
| const Arg &Item) { |
| Result += Item; |
| } |
| |
| template <typename Sep, typename Arg1, typename... Args> |
| inline void join_items_impl(std::string &Result, Sep Separator, const Arg1 &A1, |
| Args &&... Items) { |
| Result += A1; |
| Result += Separator; |
| join_items_impl(Result, Separator, std::forward<Args>(Items)...); |
| } |
| |
| inline size_t join_one_item_size(char C) { return 1; } |
| inline size_t join_one_item_size(const char *S) { return S ? ::strlen(S) : 0; } |
| |
| template <typename T> inline size_t join_one_item_size(const T &Str) { |
| return Str.size(); |
| } |
| |
| inline size_t join_items_size() { return 0; } |
| |
| template <typename A1> inline size_t join_items_size(const A1 &A) { |
| return join_one_item_size(A); |
| } |
| template <typename A1, typename... Args> |
| inline size_t join_items_size(const A1 &A, Args &&... Items) { |
| return join_one_item_size(A) + join_items_size(std::forward<Args>(Items)...); |
| } |
| |
| } // end namespace detail |
| |
| /// Joins the strings in the range [Begin, End), adding Separator between |
| /// the elements. |
| template <typename IteratorT> |
| inline std::string join(IteratorT Begin, IteratorT End, StringRef Separator) { |
| using tag = typename std::iterator_traits<IteratorT>::iterator_category; |
| return detail::join_impl(Begin, End, Separator, tag()); |
| } |
| |
| /// Joins the strings in the range [R.begin(), R.end()), adding Separator |
| /// between the elements. |
| template <typename Range> |
| inline std::string join(Range &&R, StringRef Separator) { |
| return join(R.begin(), R.end(), Separator); |
| } |
| |
| /// Joins the strings in the parameter pack \p Items, adding \p Separator |
| /// between the elements. All arguments must be implicitly convertible to |
| /// std::string, or there should be an overload of std::string::operator+=() |
| /// that accepts the argument explicitly. |
| template <typename Sep, typename... Args> |
| inline std::string join_items(Sep Separator, Args &&... Items) { |
| std::string Result; |
| if (sizeof...(Items) == 0) |
| return Result; |
| |
| size_t NS = detail::join_one_item_size(Separator); |
| size_t NI = detail::join_items_size(std::forward<Args>(Items)...); |
| Result.reserve(NI + (sizeof...(Items) - 1) * NS + 1); |
| detail::join_items_impl(Result, Separator, std::forward<Args>(Items)...); |
| return Result; |
| } |
| |
| } // end namespace llvm |
| |
| #endif // LLVM_ADT_STRINGEXTRAS_H |