//===- 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 "llvh/ADT/ArrayRef.h"

#include "llvh/ADT/SmallString.h"

#include "llvh/ADT/StringRef.h"

#include "llvh/ADT/Twine.h"

#include <cassert>

#include <cstddef>

#include <cstdint>

#include <cstdlib>

#include <cstring>

#include <iterator>

#include <string>

#include <utility>

namespace llvh {

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).

inline char hexdigit(unsigned X, bool LowerCase = false) {

  const char HexChar = LowerCase ? 'a' : 'A';

  return X < 10 ? '0' + X : HexChar + X - 10;

}

/// Given an array of c-style strings terminated by a null pointer, construct

/// a vector of StringRefs representing the same strings without the terminating

/// null string.

inline std::vector<StringRef> toStringRefArray(const char *const *Strings) {

  std::vector<StringRef> Result;

  while (*Strings)

    Result.push_back(*Strings++);

  return Result;

}

/// Construct a string ref from a boolean.

inline StringRef toStringRef(bool B) { return StringRef(B ? "true" : "false"); }

/// Construct a string ref from an array ref of unsigned chars.

inline StringRef toStringRef(ArrayRef<uint8_t> Input) {

  return StringRef(reinterpret_cast<const char *>(Input.begin()), Input.size());

}

/// Construct a string ref from an array ref of unsigned chars.

inline ArrayRef<uint8_t> arrayRefFromStringRef(StringRef Input) {

  return {Input.bytes_begin(), Input.bytes_end()};

}

/// 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.

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.

inline bool isDigit(char C) { return C >= '0' && C <= '9'; }

/// Checks if character \p C is a hexadecimal numeric character.

inline bool isHexDigit(char C) { return hexDigitValue(C) != -1U; }

/// Checks if character \p C is a valid letter as classified by "C" locale.

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.

inline bool isAlnum(char C) { return isAlpha(C) || isDigit(C); }

/// Checks whether character \p C is valid ASCII (high bit is zero).

inline bool isASCII(char C) { return static_cast<unsigned char>(C) <= 127; }

/// Checks whether all characters in S are ASCII.

inline bool isASCII(llvh::StringRef S) {

  for (char C : S)

    if (LLVM_UNLIKELY(!isASCII(C)))

      return false;

  return true;

}

/// Checks whether character \p C is printable.

///

/// Locale-independent version of the C standard library isprint whose results

/// may differ on different platforms.

inline bool isPrint(char C) {

  unsigned char UC = static_cast<unsigned char>(C);

  return (0x20 <= UC) && (UC <= 0x7E);

}

/// Returns the corresponding lowercase character if \p x is uppercase.

inline char toLower(char x) {

  if (x >= 'A' && x <= 'Z')

    return x - 'A' + 'a';

  return x;

}

/// Returns the corresponding uppercase character if \p x is lowercase.

inline char toUpper(char x) {

  if (x >= 'a' && x <= 'z')

    return x - 'a' + 'A';

  return x;

}

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, bool LowerCase = false) {

  static const char *const LUT = "0123456789ABCDEF";

  const uint8_t Offset = LowerCase ? 32 : 0;

  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] | Offset);

    Output.push_back(LUT[c & 15] | Offset);

  }

  return Output;

}

inline std::string toHex(ArrayRef<uint8_t> Input, bool LowerCase = false) {

  return toHex(toStringRef(Input), LowerCase);

}

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.

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;

}

/// 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;

}

Unexecuted instantiation: bool llvh::detail::to_float<float>(llvh::Twine const&, float&, float (*)(char const*, char**))

Unexecuted instantiation: bool llvh::detail::to_float<double>(llvh::Twine const&, double&, double (*)(char const*, char**))

Unexecuted instantiation: bool llvh::detail::to_float<long double>(llvh::Twine const&, long double&, long double (*)(char const*, char**))

}

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);

}

#ifndef __ANDROID__

inline bool to_float(const Twine &T, long double &Num) {

  return detail::to_float(T, Num, strtold);

}

#endif

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));

}

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");

/// Returns the English suffix for an ordinal integer (-st, -nd, -rd, -th).

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";

    }

  }

}

/// 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);

/// Print each character of the specified string, escaping HTML special

/// characters.

void printHTMLEscaped(StringRef String, raw_ostream &Out);

/// printLowerCase - Print each character as lowercase if it is uppercase.

void printLowerCase(StringRef String, 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 llvh

#endif // LLVM_ADT_STRINGEXTRAS_H