// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2018 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
/**
* Utilities for converting data from/to strings.
*/
#ifndef BITCOIN_UTIL_STRENCODINGS_H
#define BITCOIN_UTIL_STRENCODINGS_H
#include <attributes.h>
#include <cstdint>
#include <string>
#include <vector>
#define ARRAYLEN(array) (sizeof(array)/sizeof((array)[0]))
/** Used by SanitizeString() */
enum SafeChars
{
SAFE_CHARS_DEFAULT, //!< The full set of allowed chars
SAFE_CHARS_UA_COMMENT, //!< BIP-0014 subset
SAFE_CHARS_FILENAME, //!< Chars allowed in filenames
SAFE_CHARS_URI, //!< Chars allowed in URIs (RFC 3986)
};
/**
* Remove unsafe chars. Safe chars chosen to allow simple messages/URLs/email
* addresses, but avoid anything even possibly remotely dangerous like & or >
* @param[in] str The string to sanitize
* @param[in] rule The set of safe chars to choose (default: least restrictive)
* @return A new string without unsafe chars
*/
std::string SanitizeString(const std::string& str, int rule = SAFE_CHARS_DEFAULT);
std::vector<unsigned char> ParseHex(const char* psz);
std::vector<unsigned char> ParseHex(const std::string& str);
signed char HexDigit(char c);
/* Returns true if each character in str is a hex character, and has an even
* number of hex digits.*/
bool IsHex(const std::string& str);
/**
* Return true if the string is a hex number, optionally prefixed with "0x"
*/
bool IsHexNumber(const std::string& str);
std::vector<unsigned char> DecodeBase64(const char* p, bool* pf_invalid = nullptr);
std::string DecodeBase64(const std::string& str, bool* pf_invalid = nullptr);
std::string EncodeBase64(const unsigned char* pch, size_t len);
std::string EncodeBase64(const std::string& str);
std::vector<unsigned char> DecodeBase32(const char* p, bool* pf_invalid = nullptr);
std::string DecodeBase32(const std::string& str, bool* pf_invalid = nullptr);
std::string EncodeBase32(const unsigned char* pch, size_t len);
std::string EncodeBase32(const std::string& str);
void SplitHostPort(std::string in, int &portOut, std::string &hostOut);
std::string i64tostr(int64_t n);
std::string itostr(int n);
int64_t atoi64(const char* psz);
int64_t atoi64(const std::string& str);
int atoi(const std::string& str);
/**
* Tests if the given character is a decimal digit.
* @param[in] c character to test
* @return true if the argument is a decimal digit; otherwise false.
*/
constexpr bool IsDigit(char c)
{
return c >= '0' && c <= '9';
}
/**
* Tests if the given character is a whitespace character. The whitespace characters
* are: space, form-feed ('\f'), newline ('\n'), carriage return ('\r'), horizontal
* tab ('\t'), and vertical tab ('\v').
*
* This function is locale independent. Under the C locale this function gives the
* same result as std::isspace.
*
* @param[in] c character to test
* @return true if the argument is a whitespace character; otherwise false
*/
constexpr inline bool IsSpace(char c) noexcept {
return c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v';
}
/**
* Convert string to signed 32-bit integer with strict parse error feedback.
* @returns true if the entire string could be parsed as valid integer,
* false if not the entire string could be parsed or when overflow or underflow occurred.
*/
NODISCARD bool ParseInt32(const std::string& str, int32_t *out);
/**
* Convert string to signed 64-bit integer with strict parse error feedback.
* @returns true if the entire string could be parsed as valid integer,
* false if not the entire string could be parsed or when overflow or underflow occurred.
*/
NODISCARD bool ParseInt64(const std::string& str, int64_t *out);
/**
* Convert decimal string to unsigned 32-bit integer with strict parse error feedback.
* @returns true if the entire string could be parsed as valid integer,
* false if not the entire string could be parsed or when overflow or underflow occurred.
*/
NODISCARD bool ParseUInt32(const std::string& str, uint32_t *out);
/**
* Convert decimal string to unsigned 64-bit integer with strict parse error feedback.
* @returns true if the entire string could be parsed as valid integer,
* false if not the entire string could be parsed or when overflow or underflow occurred.
*/
NODISCARD bool ParseUInt64(const std::string& str, uint64_t *out);
/**
* Convert string to double with strict parse error feedback.
* @returns true if the entire string could be parsed as valid double,
* false if not the entire string could be parsed or when overflow or underflow occurred.
*/
NODISCARD bool ParseDouble(const std::string& str, double *out);
template<typename T>
std::string HexStr(const T itbegin, const T itend, bool fSpaces=false)
{
std::string rv;
static const char hexmap[16] = { '0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
rv.reserve((itend-itbegin)*3);
for(T it = itbegin; it < itend; ++it)
{
unsigned char val = (unsigned char)(*it);
if(fSpaces && it != itbegin)
rv.push_back(' ');
rv.push_back(hexmap[val>>4]);
rv.push_back(hexmap[val&15]);
}
return rv;
}
template<typename T>
inline std::string HexStr(const T& vch, bool fSpaces=false)
{
return HexStr(vch.begin(), vch.end(), fSpaces);
}
/**
* Format a paragraph of text to a fixed width, adding spaces for
* indentation to any added line.
*/
std::string FormatParagraph(const std::string& in, size_t width = 79, size_t indent = 0);
/**
* Timing-attack-resistant comparison.
* Takes time proportional to length
* of first argument.
*/
template <typename T>
bool TimingResistantEqual(const T& a, const T& b)
{
if (b.size() == 0) return a.size() == 0;
size_t accumulator = a.size() ^ b.size();
for (size_t i = 0; i < a.size(); i++)
accumulator |= a[i] ^ b[i%b.size()];
return accumulator == 0;
}
/** Parse number as fixed point according to JSON number syntax.
* See http://json.org/number.gif
* @returns true on success, false on error.
* @note The result must be in the range (-10^18,10^18), otherwise an overflow error will trigger.
*/
NODISCARD bool ParseFixedPoint(const std::string &val, int decimals, int64_t *amount_out);
/** Convert from one power-of-2 number base to another. */
template<int frombits, int tobits, bool pad, typename O, typename I>
bool ConvertBits(const O& outfn, I it, I end) {
size_t acc = 0;
size_t bits = 0;
constexpr size_t maxv = (1 << tobits) - 1;
constexpr size_t max_acc = (1 << (frombits + tobits - 1)) - 1;
while (it != end) {
acc = ((acc << frombits) | *it) & max_acc;
bits += frombits;
while (bits >= tobits) {
bits -= tobits;
outfn((acc >> bits) & maxv);
}
++it;
}
if (pad) {
if (bits) outfn((acc << (tobits - bits)) & maxv);
} else if (bits >= frombits || ((acc << (tobits - bits)) & maxv)) {
return false;
}
return true;
}
/**
* Converts the given character to its lowercase equivalent.
* This function is locale independent. It only converts uppercase
* characters in the standard 7-bit ASCII range.
* @param[in] c the character to convert to lowercase.
* @return the lowercase equivalent of c; or the argument
* if no conversion is possible.
*/
constexpr char ToLower(char c)
{
return (c >= 'A' && c <= 'Z' ? (c - 'A') + 'a' : c);
}
/**
* Converts the given string to its lowercase equivalent.
* This function is locale independent. It only converts uppercase
* characters in the standard 7-bit ASCII range.
* @param[in,out] str the string to convert to lowercase.
*/
void Downcase(std::string& str);
/**
* Converts the given character to its uppercase equivalent.
* This function is locale independent. It only converts lowercase
* characters in the standard 7-bit ASCII range.
* @param[in] c the character to convert to uppercase.
* @return the uppercase equivalent of c; or the argument
* if no conversion is possible.
*/
constexpr char ToUpper(char c)
{
return (c >= 'a' && c <= 'z' ? (c - 'a') + 'A' : c);
}
/**
* Capitalizes the first character of the given string.
* This function is locale independent. It only capitalizes the
* first character of the argument if it has an uppercase equivalent
* in the standard 7-bit ASCII range.
* @param[in] str the string to capitalize.
* @return string with the first letter capitalized.
*/
std::string Capitalize(std::string str);
#endif // BITCOIN_UTIL_STRENCODINGS_H