src/utilstrencodings.h

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2016 The Bitcoin Core developers
   3 // Distributed under the MIT software license, see the accompanying
   4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5
   6 /**
   7  * Utilities for converting data from/to strings.
   8  */
   9 #ifndef BITCOIN_UTILSTRENCODINGS_H
  10 #define BITCOIN_UTILSTRENCODINGS_H
  11
  12 #include <stdint.h>
  13 #include <string>
  14 #include <vector>
  15
  16 #define BEGIN(a)            ((char*)&(a))
  17 #define END(a)              ((char*)&((&(a))[1]))
  18 #define UBEGIN(a)           ((unsigned char*)&(a))
  19 #define UEND(a)             ((unsigned char*)&((&(a))[1]))
  20 #define ARRAYLEN(array)     (sizeof(array)/sizeof((array)[0]))
  21
  22 /** Used by SanitizeString() */
  23 enum SafeChars
  24 {
  25     SAFE_CHARS_DEFAULT, //!< The full set of allowed chars
  26     SAFE_CHARS_UA_COMMENT, //!< BIP-0014 subset
  27     SAFE_CHARS_FILENAME, //!< Chars allowed in filenames
  28 };
  29
  30 /**
  31 * Remove unsafe chars. Safe chars chosen to allow simple messages/URLs/email
  32 * addresses, but avoid anything even possibly remotely dangerous like & or >
  33 * @param[in] str    The string to sanitize
  34 * @param[in] rule   The set of safe chars to choose (default: least restrictive)
  35 * @return           A new string without unsafe chars
  36 */
  37 std::string SanitizeString(const std::string& str, int rule = SAFE_CHARS_DEFAULT);
  38 std::vector<unsigned char> ParseHex(const char* psz);
  39 std::vector<unsigned char> ParseHex(const std::string& str);
  40 signed char HexDigit(char c);
  41 bool IsHex(const std::string& str);
  42 std::vector<unsigned char> DecodeBase64(const char* p, bool* pfInvalid = nullptr);
  43 std::string DecodeBase64(const std::string& str);
  44 std::string EncodeBase64(const unsigned char* pch, size_t len);
  45 std::string EncodeBase64(const std::string& str);
  46 std::vector<unsigned char> DecodeBase32(const char* p, bool* pfInvalid = nullptr);
  47 std::string DecodeBase32(const std::string& str);
  48 std::string EncodeBase32(const unsigned char* pch, size_t len);
  49 std::string EncodeBase32(const std::string& str);
  50
  51 void SplitHostPort(std::string in, int &portOut, std::string &hostOut);
  52 std::string i64tostr(int64_t n);
  53 std::string itostr(int n);
  54 int64_t atoi64(const char* psz);
  55 int64_t atoi64(const std::string& str);
  56 int atoi(const std::string& str);
  57
  58 /**
  59  * Convert string to signed 32-bit integer with strict parse error feedback.
  60  * @returns true if the entire string could be parsed as valid integer,
  61  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  62  */
  63 bool ParseInt32(const std::string& str, int32_t *out);
  64
  65 /**
  66  * Convert string to signed 64-bit integer with strict parse error feedback.
  67  * @returns true if the entire string could be parsed as valid integer,
  68  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  69  */
  70 bool ParseInt64(const std::string& str, int64_t *out);
  71
  72 /**
  73  * Convert decimal string to unsigned 32-bit integer with strict parse error feedback.
  74  * @returns true if the entire string could be parsed as valid integer,
  75  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  76  */
  77 bool ParseUInt32(const std::string& str, uint32_t *out);
  78
  79 /**
  80  * Convert decimal string to unsigned 64-bit integer with strict parse error feedback.
  81  * @returns true if the entire string could be parsed as valid integer,
  82  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  83  */
  84 bool ParseUInt64(const std::string& str, uint64_t *out);
  85
  86 /**
  87  * Convert string to double with strict parse error feedback.
  88  * @returns true if the entire string could be parsed as valid double,
  89  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  90  */
  91 bool ParseDouble(const std::string& str, double *out);
  92
  93 template<typename T>
  94 std::string HexStr(const T itbegin, const T itend, bool fSpaces=false)
  95 {
  96     std::string rv;
  97     static const char hexmap[16] = { '0', '1', '2', '3', '4', '5', '6', '7',
  98                                      '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
  99     rv.reserve((itend-itbegin)*3);
 100     for(T it = itbegin; it < itend; ++it)
 101     {
 102         unsigned char val = (unsigned char)(*it);
 103         if(fSpaces && it != itbegin)
 104             rv.push_back(' ');
 105         rv.push_back(hexmap[val>>4]);
 106         rv.push_back(hexmap[val&15]);
 107     }
 108
 109     return rv;
 110 }
 111
 112 template<typename T>
 113 inline std::string HexStr(const T& vch, bool fSpaces=false)
 114 {
 115     return HexStr(vch.begin(), vch.end(), fSpaces);
 116 }
 117
 118 /**
 119  * Format a paragraph of text to a fixed width, adding spaces for
 120  * indentation to any added line.
 121  */
 122 std::string FormatParagraph(const std::string& in, size_t width = 79, size_t indent = 0);
 123
 124 /**
 125  * Timing-attack-resistant comparison.
 126  * Takes time proportional to length
 127  * of first argument.
 128  */
 129 template <typename T>
 130 bool TimingResistantEqual(const T& a, const T& b)
 131 {
 132     if (b.size() == 0) return a.size() == 0;
 133     size_t accumulator = a.size() ^ b.size();
 134     for (size_t i = 0; i < a.size(); i++)
 135         accumulator |= a[i] ^ b[i%b.size()];
 136     return accumulator == 0;
 137 }
 138
 139 /** Parse number as fixed point according to JSON number syntax.
 140  * See http://json.org/number.gif
 141  * @returns true on success, false on error.
 142  * @note The result must be in the range (-10^18,10^18), otherwise an overflow error will trigger.
 143  */
 144 bool ParseFixedPoint(const std::string &val, int decimals, int64_t *amount_out);
 145
 146 #endif // BITCOIN_UTILSTRENCODINGS_H