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-rw-r--r--src/util/strencodings.cpp599
1 files changed, 599 insertions, 0 deletions
diff --git a/src/util/strencodings.cpp b/src/util/strencodings.cpp
new file mode 100644
index 0000000000..5b8520030b
--- /dev/null
+++ b/src/util/strencodings.cpp
@@ -0,0 +1,599 @@
+// 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.
+
+#include <util/strencodings.h>
+
+#include <tinyformat.h>
+
+#include <algorithm>
+#include <cstdlib>
+#include <cstring>
+#include <errno.h>
+#include <limits>
+
+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;
+}
+
+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);
+}
+
+bool IsHexNumber(const std::string& str)
+{
+ size_t starting_location = 0;
+ if (str.size() > 2 && *str.begin() == '0' && *(str.begin()+1) == 'x') {
+ starting_location = 2;
+ }
+ for (const char c : str.substr(starting_location)) {
+ if (HexDigit(c) < 0) return false;
+ }
+ // Return false for empty string or "0x".
+ return (str.size() > starting_location);
+}
+
+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());
+}
+
+void SplitHostPort(std::string in, int &portOut, std::string &hostOut) {
+ size_t colon = in.find_last_of(':');
+ // if a : is found, and it either follows a [...], or no other : is in the string, treat it as port separator
+ bool fHaveColon = colon != in.npos;
+ bool fBracketed = fHaveColon && (in[0]=='[' && in[colon-1]==']'); // if there is a colon, and in[0]=='[', colon is not 0, so in[colon-1] is safe
+ bool fMultiColon = fHaveColon && (in.find_last_of(':',colon-1) != in.npos);
+ if (fHaveColon && (colon==0 || fBracketed || !fMultiColon)) {
+ int32_t n;
+ if (ParseInt32(in.substr(colon + 1), &n) && n > 0 && n < 0x10000) {
+ in = in.substr(0, colon);
+ portOut = n;
+ }
+ }
+ if (in.size()>0 && in[0] == '[' && in[in.size()-1] == ']')
+ hostOut = in.substr(1, in.size()-2);
+ else
+ hostOut = in;
+}
+
+std::string EncodeBase64(const unsigned char* pch, size_t len)
+{
+ static const char *pbase64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+ std::string str;
+ str.reserve(((len + 2) / 3) * 4);
+ ConvertBits<8, 6, true>([&](int v) { str += pbase64[v]; }, pch, pch + len);
+ while (str.size() % 4) str += '=';
+ return str;
+}
+
+std::string EncodeBase64(const std::string& str)
+{
+ return EncodeBase64((const unsigned char*)str.c_str(), str.size());
+}
+
+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(const unsigned char* pch, size_t len)
+{
+ static const char *pbase32 = "abcdefghijklmnopqrstuvwxyz234567";
+
+ std::string str;
+ str.reserve(((len + 4) / 5) * 8);
+ ConvertBits<8, 5, true>([&](int v) { str += pbase32[v]; }, pch, pch + len);
+ while (str.size() % 8) str += '=';
+ return str;
+}
+
+std::string EncodeBase32(const std::string& str)
+{
+ return EncodeBase32((const unsigned char*)str.c_str(), str.size());
+}
+
+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 (str.size() != strlen(str.c_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 an 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 an 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 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 ParseUInt64(const std::string& str, uint64_t *out)
+{
+ if (!ParsePrechecks(str))
+ return false;
+ if (str.size() >= 1 && str[0] == '-') // Reject negative values, unfortunately strtoull accepts these by default if they fit in the range
+ return false;
+ char *endp = nullptr;
+ errno = 0; // strtoull will not set errno if valid
+ unsigned long long int n = strtoull(str.c_str(), &endp, 10);
+ if(out) *out = (uint64_t)n;
+ // Note that strtoull returns a *unsigned long 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 *uint64_t*.
+ return endp && *endp == 0 && !errno &&
+ n <= std::numeric_limits<uint64_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 ptr = 0;
+ size_t indented = 0;
+ while (ptr < in.size())
+ {
+ size_t lineend = in.find_first_of('\n', ptr);
+ if (lineend == std::string::npos) {
+ lineend = in.size();
+ }
+ const size_t linelen = lineend - ptr;
+ const size_t rem_width = width - indented;
+ if (linelen <= rem_width) {
+ out << in.substr(ptr, linelen + 1);
+ ptr = lineend + 1;
+ indented = 0;
+ } else {
+ size_t finalspace = in.find_last_of(" \n", ptr + rem_width);
+ if (finalspace == std::string::npos || finalspace < ptr) {
+ // No place to break; just include the entire word and move on
+ finalspace = in.find_first_of("\n ", ptr);
+ if (finalspace == std::string::npos) {
+ // End of the string, just add it and break
+ out << in.substr(ptr);
+ break;
+ }
+ }
+ out << in.substr(ptr, finalspace - ptr) << "\n";
+ if (in[finalspace] == '\n') {
+ indented = 0;
+ } else if (indent) {
+ out << std::string(indent, ' ');
+ indented = indent;
+ }
+ ptr = finalspace + 1;
+ }
+ }
+ 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());
+}
+
+/** Upper bound for mantissa.
+ * 10^18-1 is the largest arbitrary decimal that will fit in a signed 64-bit integer.
+ * Larger integers cannot consist of arbitrary combinations of 0-9:
+ *
+ * 999999999999999999 1^18-1
+ * 9223372036854775807 (1<<63)-1 (max int64_t)
+ * 9999999999999999999 1^19-1 (would overflow)
+ */
+static const int64_t UPPER_BOUND = 1000000000000000000LL - 1LL;
+
+/** Helper function for ParseFixedPoint */
+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;
+}
+
+bool ParseHDKeypath(const std::string& keypath_str, std::vector<uint32_t>& keypath)
+{
+ std::stringstream ss(keypath_str);
+ std::string item;
+ bool first = true;
+ while (std::getline(ss, item, '/')) {
+ if (item.compare("m") == 0) {
+ if (first) {
+ first = false;
+ continue;
+ }
+ return false;
+ }
+ // Finds whether it is hardened
+ uint32_t path = 0;
+ size_t pos = item.find("'");
+ if (pos != std::string::npos) {
+ // The hardened tick can only be in the last index of the string
+ if (pos != item.size() - 1) {
+ return false;
+ }
+ path |= 0x80000000;
+ item = item.substr(0, item.size() - 1); // Drop the last character which is the hardened tick
+ }
+
+ // Ensure this is only numbers
+ if (item.find_first_not_of( "0123456789" ) != std::string::npos) {
+ return false;
+ }
+ uint32_t number;
+ if (!ParseUInt32(item, &number)) {
+ return false;
+ }
+ path |= number;
+
+ keypath.push_back(path);
+ first = false;
+ }
+ return true;
+}
+
+void Downcase(std::string& str)
+{
+ std::transform(str.begin(), str.end(), str.begin(), [](unsigned char c){return ToLower(c);});
+}
+
+std::string Capitalize(std::string str)
+{
+ if (str.empty()) return str;
+ str[0] = ToUpper(str.front());
+ return str;
+}