utilstrencodings.cpp

Go to the documentation of this file.

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2014 The Bitcoin developers
// Copyright (c) 2016-2022 The PIVX Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
#include "utilstrencodings.h"
#include "util/string.h"
 
#include "tinyformat.h"
 
#include <algorithm>
#include <cstdlib>
#include <cstring>
#include <errno.h>
#include <limits>
#include <regex>
 
 
 
static const std::string CHARS_ALPHA_NUM = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
 
static const std::string SAFE_CHARS[] =
{
    CHARS_ALPHA_NUM + " .,;-_/:?@()", // SAFE_CHARS_DEFAULT
    CHARS_ALPHA_NUM + " .,;-_?@", // SAFE_CHARS_UA_COMMENT
    CHARS_ALPHA_NUM + ".-_", // SAFE_CHARS_FILENAME
};
 
std::string SanitizeString(const std::string& str, int rule)
{
    std::string strResult;
    for (std::string::size_type i = 0; i < str.size(); i++)
    {
        if (SAFE_CHARS[rule].find(str[i]) != std::string::npos)
            strResult.push_back(str[i]);
    }
    return strResult;
}
 
bool validateURL(const std::string& strURL)
{
    std::string strErr;
    return validateURL(strURL, strErr);
}
 
bool validateURL(const std::string& strURL, std::string& strErr, unsigned int maxSize)
{
    // Check URL size
    if (strURL.size() > maxSize) {
        strErr = strprintf("Invalid URL: %d exceeds limit of %d characters.", strURL.size(), maxSize);
        return false;
    }
 
    // Validate URL
    std::regex url_regex(R"(^(https?)://[^\s/$.?#][^\s]*[^\s/.]\.[^\s/.][^\s]*[^\s.]$)");
    if (!std::regex_match(strURL, url_regex)) {
        strErr = "Invalid URL";
        return false;
    }
 
    return true;
}
 
const signed char p_util_hexdigit[256] =
    {
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1,
        -1, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
};
 
signed char HexDigit(char c)
{
    return p_util_hexdigit[(unsigned char)c];
}
 
bool IsHex(const std::string& str)
{
    for (std::string::const_iterator it(str.begin()); it != str.end(); ++it) {
        if (HexDigit(*it) < 0)
            return false;
    }
    return (str.size() > 0) && (str.size() % 2 == 0);
}
 
std::vector<unsigned char> ParseHex(const char* psz)
{
    // convert hex dump to vector
    std::vector<unsigned char> vch;
    while (true) {
        while (isspace(*psz))
            psz++;
        signed char c = HexDigit(*psz++);
        if (c == (signed char)-1)
            break;
        unsigned char n = (c << 4);
        c = HexDigit(*psz++);
        if (c == (signed char)-1)
            break;
        n |= c;
        vch.push_back(n);
    }
    return vch;
}
 
std::vector<unsigned char> ParseHex(const std::string& str)
{
    return ParseHex(str.c_str());
}
 
std::string EncodeBase64(Span<const unsigned char> input)
{
    static const char *pbase64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
    std::string str;
    str.reserve(((input.size() + 2) / 3) * 4);
    ConvertBits<8, 6, true>([&](int v) { str += pbase64[v]; }, input.begin(), input.end());
    while (str.size() % 4) str += '=';
    return str;
}
 
std::string EncodeBase64(const std::string& str)
{
    return EncodeBase64(MakeUCharSpan(str));
}
 
std::vector<unsigned char> DecodeBase64(const char* p, bool* pfInvalid)
{
    static const int decode64_table[256] =
    {
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1,
        -1, -1, -1, -1, -1,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
        15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28,
        29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
        49, 50, 51, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
    };
 
    const char* e = p;
    std::vector<uint8_t> val;
    val.reserve(strlen(p));
    while (*p != 0) {
        int x = decode64_table[(unsigned char)*p];
        if (x == -1) break;
        val.push_back(x);
        ++p;
    }
 
    std::vector<unsigned char> ret;
    ret.reserve((val.size() * 3) / 4);
    bool valid = ConvertBits<6, 8, false>([&](unsigned char c) { ret.push_back(c); }, val.begin(), val.end());
 
    const char* q = p;
    while (valid && *p != 0) {
        if (*p != '=') {
            valid = false;
            break;
        }
        ++p;
    }
    valid = valid && (p - e) % 4 == 0 && p - q < 4;
    if (pfInvalid) *pfInvalid = !valid;
 
    return ret;
}
 
std::string DecodeBase64(const std::string& str)
{
    std::vector<unsigned char> vchRet = DecodeBase64(str.c_str());
    return std::string((const char*)vchRet.data(), vchRet.size());
}
 
std::string EncodeBase32(Span<const unsigned char> input, bool pad)
{
    static const char *pbase32 = "abcdefghijklmnopqrstuvwxyz234567";
 
    std::string str;
    str.reserve(((input.size() + 4) / 5) * 8);
    ConvertBits<8, 5, true>([&](int v) { str += pbase32[v]; }, input.begin(), input.end());
    if (pad) {
        while (str.size() % 8) {
            str += '=';
        }
    }
    return str;
}
 
std::string EncodeBase32(const std::string& str, bool pad)
{
    return EncodeBase32(MakeUCharSpan(str), pad);
}
 
 
std::vector<unsigned char> DecodeBase32(const char* p, bool* pfInvalid)
{
    static const int decode32_table[256] =
    {
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, -1, -1, -1, -1,
        -1, -1, -1, -1, -1,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
        15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1,  0,  1,  2,
         3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
        23, 24, 25, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
    };
 
    const char* e = p;
    std::vector<uint8_t> val;
    val.reserve(strlen(p));
    while (*p != 0) {
        int x = decode32_table[(unsigned char)*p];
        if (x == -1) break;
        val.push_back(x);
        ++p;
    }
 
    std::vector<unsigned char> ret;
    ret.reserve((val.size() * 5) / 8);
    bool valid = ConvertBits<5, 8, false>([&](unsigned char c) { ret.push_back(c); }, val.begin(), val.end());
 
    const char* q = p;
    while (valid && *p != 0) {
        if (*p != '=') {
            valid = false;
            break;
        }
        ++p;
    }
    valid = valid && (p - e) % 8 == 0 && p - q < 8;
    if (pfInvalid) *pfInvalid = !valid;
 
    return ret;
}
 
std::string DecodeBase32(const std::string& str)
{
    std::vector<unsigned char> vchRet = DecodeBase32(str.c_str());
    return std::string((const char*)vchRet.data(), vchRet.size());
}
 
static bool ParsePrechecks(const std::string& str)
{
    if (str.empty()) // No empty string allowed
        return false;
    if (str.size() >= 1 && (isspace(str[0]) || isspace(str[str.size()-1]))) // No padding allowed
        return false;
    if (!ValidAsCString(str)) // No embedded NUL characters allowed
        return false;
    return true;
}
 
bool ParseInt32(const std::string& str, int32_t *out)
{
    if (!ParsePrechecks(str))
        return false;
    char *endp = nullptr;
    errno = 0; // strtol will not set errno if valid
    long int n = strtol(str.c_str(), &endp, 10);
    if(out) *out = (int32_t)n;
    // Note that strtol returns a *long int*, so even if strtol doesn't report a over/underflow
    // we still have to check that the returned value is within the range of an *int32_t*. On 64-bit
    // platforms the size of these types may be different.
    return endp && *endp == 0 && !errno &&
        n >= std::numeric_limits<int32_t>::min() &&
        n <= std::numeric_limits<int32_t>::max();
}
 
bool ParseInt64(const std::string& str, int64_t *out)
{
    if (!ParsePrechecks(str))
        return false;
    char *endp = nullptr;
    errno = 0; // strtoll will not set errno if valid
    long long int n = strtoll(str.c_str(), &endp, 10);
    if(out) *out = (int64_t)n;
    // Note that strtoll returns a *long long int*, so even if strtol doesn't report a over/underflow
    // we still have to check that the returned value is within the range of an *int64_t*.
    return endp && *endp == 0 && !errno &&
        n >= std::numeric_limits<int64_t>::min() &&
        n <= std::numeric_limits<int64_t>::max();
}
 
bool ParseUInt8(const std::string& str, uint8_t *out)
{
    uint32_t u32;
    if (!ParseUInt32(str, &u32) || u32 > std::numeric_limits<uint8_t>::max()) {
        return false;
    }
    if (out != nullptr) {
        *out = static_cast<uint8_t>(u32);
    }
    return true;
}
 
bool ParseUInt32(const std::string& str, uint32_t *out)
{
    if (!ParsePrechecks(str))
        return false;
    if (str.size() >= 1 && str[0] == '-') // Reject negative values, unfortunately strtoul accepts these by default if they fit in the range
        return false;
    char *endp = nullptr;
    errno = 0; // strtoul will not set errno if valid
    unsigned long int n = strtoul(str.c_str(), &endp, 10);
    if(out) *out = (uint32_t)n;
    // Note that strtoul returns a *unsigned long int*, so even if it doesn't report an over/underflow
    // we still have to check that the returned value is within the range of an *uint32_t*. On 64-bit
    // platforms the size of these types may be different.
    return endp && *endp == 0 && !errno &&
           n <= std::numeric_limits<uint32_t>::max();
}
 
bool ParseDouble(const std::string& str, double *out)
{
    if (!ParsePrechecks(str))
        return false;
    if (str.size() >= 2 && str[0] == '0' && str[1] == 'x') // No hexadecimal floats allowed
        return false;
    std::istringstream text(str);
    text.imbue(std::locale::classic());
    double result;
    text >> result;
    if(out) *out = result;
    return text.eof() && !text.fail();
}
 
std::string FormatParagraph(const std::string in, size_t width, size_t indent)
{
    std::stringstream out;
    size_t col = 0;
    size_t ptr = 0;
    while (ptr < in.size()) {
        // Find beginning of next word
        ptr = in.find_first_not_of(' ', ptr);
        if (ptr == std::string::npos)
            break;
        // Find end of next word
        size_t endword = in.find_first_of(' ', ptr);
        if (endword == std::string::npos)
            endword = in.size();
        // Add newline and indentation if this wraps over the allowed width
        if (col > 0) {
            if ((col + endword - ptr) > width) {
                out << '\n';
                for (size_t i = 0; i < indent; ++i)
                    out << ' ';
                col = 0;
            } else
                out << ' ';
        }
        // Append word
        out << in.substr(ptr, endword - ptr);
        col += endword - ptr + 1;
        ptr = endword;
    }
    return out.str();
}
 
std::string i64tostr(int64_t n)
{
    return strprintf("%d", n);
}
 
std::string itostr(int n)
{
    return strprintf("%d", n);
}
 
int64_t atoi64(const char* psz)
{
#ifdef _MSC_VER
    return _atoi64(psz);
#else
    return strtoll(psz, nullptr, 10);
#endif
}
 
int64_t atoi64(const std::string& str)
{
#ifdef _MSC_VER
    return _atoi64(str.c_str());
#else
    return strtoll(str.c_str(), nullptr, 10);
#endif
}
 
int atoi(const std::string& str)
{
    return atoi(str.c_str());
}
 
 
static const int64_t UPPER_BOUND = 1000000000000000000LL - 1LL;
 
static inline bool ProcessMantissaDigit(char ch, int64_t &mantissa, int &mantissa_tzeros)
{
    if(ch == '0')
        ++mantissa_tzeros;
    else {
        for (int i=0; i<=mantissa_tzeros; ++i) {
            if (mantissa > (UPPER_BOUND / 10LL))
                return false; /* overflow */
            mantissa *= 10;
        }
        mantissa += ch - '0';
        mantissa_tzeros = 0;
    }
    return true;
}
 
bool ParseFixedPoint(const std::string &val, int decimals, int64_t *amount_out)
{
    int64_t mantissa = 0;
    int64_t exponent = 0;
    int mantissa_tzeros = 0;
    bool mantissa_sign = false;
    bool exponent_sign = false;
    int ptr = 0;
    int end = val.size();
    int point_ofs = 0;
 
    if (ptr < end && val[ptr] == '-') {
        mantissa_sign = true;
        ++ptr;
    }
    if (ptr < end)
    {
        if (val[ptr] == '0') {
            /* pass single 0 */
            ++ptr;
        } else if (val[ptr] >= '1' && val[ptr] <= '9') {
            while (ptr < end && IsDigit(val[ptr])) {
                if (!ProcessMantissaDigit(val[ptr], mantissa, mantissa_tzeros))
                    return false; /* overflow */
                ++ptr;
            }
        } else return false; /* missing expected digit */
    } else return false; /* empty string or loose '-' */
    if (ptr < end && val[ptr] == '.')
    {
        ++ptr;
        if (ptr < end && IsDigit(val[ptr]))
        {
            while (ptr < end && IsDigit(val[ptr])) {
                if (!ProcessMantissaDigit(val[ptr], mantissa, mantissa_tzeros))
                    return false; /* overflow */
                ++ptr;
                ++point_ofs;
            }
        } else return false; /* missing expected digit */
    }
    if (ptr < end && (val[ptr] == 'e' || val[ptr] == 'E'))
    {
        ++ptr;
        if (ptr < end && val[ptr] == '+')
            ++ptr;
        else if (ptr < end && val[ptr] == '-') {
            exponent_sign = true;
            ++ptr;
        }
        if (ptr < end && IsDigit(val[ptr])) {
            while (ptr < end && IsDigit(val[ptr])) {
                if (exponent > (UPPER_BOUND / 10LL))
                    return false; /* overflow */
                exponent = exponent * 10 + val[ptr] - '0';
                ++ptr;
            }
        } else return false; /* missing expected digit */
    }
    if (ptr != end)
        return false; /* trailing garbage */
 
    /* finalize exponent */
    if (exponent_sign)
        exponent = -exponent;
    exponent = exponent - point_ofs + mantissa_tzeros;
 
    /* finalize mantissa */
    if (mantissa_sign)
        mantissa = -mantissa;
 
    /* convert to one 64-bit fixed-point value */
    exponent += decimals;
    if (exponent < 0)
        return false; /* cannot represent values smaller than 10^-decimals */
    if (exponent >= 18)
        return false; /* cannot represent values larger than or equal to 10^(18-decimals) */
 
    for (int i=0; i < exponent; ++i) {
        if (mantissa > (UPPER_BOUND / 10LL) || mantissa < -(UPPER_BOUND / 10LL))
            return false; /* overflow */
        mantissa *= 10;
    }
    if (mantissa > UPPER_BOUND || mantissa < -UPPER_BOUND)
        return false; /* overflow */
 
    if (amount_out)
        *amount_out = mantissa;
 
    return true;
}
 
void Downcase(std::string& str)
{
    std::transform(str.begin(), str.end(), str.begin(), [](unsigned char c){return ToLower(c);});
}
 
std::string ToLower(const std::string& str)
{
    std::string r;
    for (auto ch : str) r += ToLower((unsigned char)ch);
    return r;
}
 
std::string ToUpper(const std::string& str)
{
    std::string r;
    for (auto ch : str) r += ToUpper((unsigned char)ch);
    return r;
}
 
std::string Capitalize(std::string str)
{
    if (str.empty()) return str;
    str[0] = ToUpper(str.front());
    return str;
}
 
std::string HexStr(const Span<const uint8_t> s)
{
    std::string rv;
    static constexpr char hexmap[16] = { '0', '1', '2', '3', '4', '5', '6', '7',
                                         '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
    rv.reserve(s.size() * 2);
    for (uint8_t v: s) {
        rv.push_back(hexmap[v >> 4]);
        rv.push_back(hexmap[v & 15]);
    }
    return rv;
}
 
// Based on http://www.zedwood.com/article/cpp-is-valid-utf8-string-function
bool IsValidUTF8(const std::string& str)
{
    const unsigned int strLen = str.length();
    int c,n;
    for (unsigned i = 0; i < strLen; i++) {
        c = (unsigned char) str[i];
        if (0x00 <= c && c <= 0x7f)     n=0;      // 0bbbbbbb (ASCII)
        else if ((c & 0xE0) == 0xC0)    n=1;      // 110bbbbb
        else if ( c == 0xED && i < (strLen - 1) && ((unsigned char)str[i+1] & 0xA0) == 0xA0)
            return false;                         //U+d800 to U+dfff
        else if ((c & 0xF0) == 0xE0)    n=2;      // 1110bbbb
        else if ((c & 0xF8) == 0xF0)    n=3;      // 11110bbb
        else return false;
        for (int j=0; j < n && i < strLen; j++) { // n bytes matching 10bbbbbb follow ?
            if ((++i == strLen) || (( (unsigned char)str[i] & 0xC0) != 0x80))
                return false;
        }
    }
    return true;
}