lbrycrd/src/utilstrencodings.cpp
2017-09-05 15:05:28 -04:00

735 lines
23 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2016 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 "utilstrencodings.h"
#include "tinyformat.h"
#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 (auto 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 strRet = "";
strRet.reserve((len+2)/3*4);
int mode=0, left=0;
const unsigned char *pchEnd = pch+len;
while (pch<pchEnd)
{
int enc = *(pch++);
switch (mode)
{
case 0: // we have no bits
strRet += pbase64[enc >> 2];
left = (enc & 3) << 4;
mode = 1;
break;
case 1: // we have two bits
strRet += pbase64[left | (enc >> 4)];
left = (enc & 15) << 2;
mode = 2;
break;
case 2: // we have four bits
strRet += pbase64[left | (enc >> 6)];
strRet += pbase64[enc & 63];
mode = 0;
break;
}
}
if (mode)
{
strRet += pbase64[left];
strRet += '=';
if (mode == 1)
strRet += '=';
}
return strRet;
}
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
};
if (pfInvalid)
*pfInvalid = false;
std::vector<unsigned char> vchRet;
vchRet.reserve(strlen(p)*3/4);
int mode = 0;
int left = 0;
while (1)
{
int dec = decode64_table[(unsigned char)*p];
if (dec == -1) break;
p++;
switch (mode)
{
case 0: // we have no bits and get 6
left = dec;
mode = 1;
break;
case 1: // we have 6 bits and keep 4
vchRet.push_back((left<<2) | (dec>>4));
left = dec & 15;
mode = 2;
break;
case 2: // we have 4 bits and get 6, we keep 2
vchRet.push_back((left<<4) | (dec>>2));
left = dec & 3;
mode = 3;
break;
case 3: // we have 2 bits and get 6
vchRet.push_back((left<<6) | dec);
mode = 0;
break;
}
}
if (pfInvalid)
switch (mode)
{
case 0: // 4n base64 characters processed: ok
break;
case 1: // 4n+1 base64 character processed: impossible
*pfInvalid = true;
break;
case 2: // 4n+2 base64 characters processed: require '=='
if (left || p[0] != '=' || p[1] != '=' || decode64_table[(unsigned char)p[2]] != -1)
*pfInvalid = true;
break;
case 3: // 4n+3 base64 characters processed: require '='
if (left || p[0] != '=' || decode64_table[(unsigned char)p[1]] != -1)
*pfInvalid = true;
break;
}
return vchRet;
}
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 strRet="";
strRet.reserve((len+4)/5*8);
int mode=0, left=0;
const unsigned char *pchEnd = pch+len;
while (pch<pchEnd)
{
int enc = *(pch++);
switch (mode)
{
case 0: // we have no bits
strRet += pbase32[enc >> 3];
left = (enc & 7) << 2;
mode = 1;
break;
case 1: // we have three bits
strRet += pbase32[left | (enc >> 6)];
strRet += pbase32[(enc >> 1) & 31];
left = (enc & 1) << 4;
mode = 2;
break;
case 2: // we have one bit
strRet += pbase32[left | (enc >> 4)];
left = (enc & 15) << 1;
mode = 3;
break;
case 3: // we have four bits
strRet += pbase32[left | (enc >> 7)];
strRet += pbase32[(enc >> 2) & 31];
left = (enc & 3) << 3;
mode = 4;
break;
case 4: // we have two bits
strRet += pbase32[left | (enc >> 5)];
strRet += pbase32[enc & 31];
mode = 0;
}
}
static const int nPadding[5] = {0, 6, 4, 3, 1};
if (mode)
{
strRet += pbase32[left];
for (int n=0; n<nPadding[mode]; n++)
strRet += '=';
}
return strRet;
}
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
};
if (pfInvalid)
*pfInvalid = false;
std::vector<unsigned char> vchRet;
vchRet.reserve((strlen(p))*5/8);
int mode = 0;
int left = 0;
while (1)
{
int dec = decode32_table[(unsigned char)*p];
if (dec == -1) break;
p++;
switch (mode)
{
case 0: // we have no bits and get 5
left = dec;
mode = 1;
break;
case 1: // we have 5 bits and keep 2
vchRet.push_back((left<<3) | (dec>>2));
left = dec & 3;
mode = 2;
break;
case 2: // we have 2 bits and keep 7
left = left << 5 | dec;
mode = 3;
break;
case 3: // we have 7 bits and keep 4
vchRet.push_back((left<<1) | (dec>>4));
left = dec & 15;
mode = 4;
break;
case 4: // we have 4 bits, and keep 1
vchRet.push_back((left<<4) | (dec>>1));
left = dec & 1;
mode = 5;
break;
case 5: // we have 1 bit, and keep 6
left = left << 5 | dec;
mode = 6;
break;
case 6: // we have 6 bits, and keep 3
vchRet.push_back((left<<2) | (dec>>3));
left = dec & 7;
mode = 7;
break;
case 7: // we have 3 bits, and keep 0
vchRet.push_back((left<<5) | dec);
mode = 0;
break;
}
}
if (pfInvalid)
switch (mode)
{
case 0: // 8n base32 characters processed: ok
break;
case 1: // 8n+1 base32 characters processed: impossible
case 3: // +3
case 6: // +6
*pfInvalid = true;
break;
case 2: // 8n+2 base32 characters processed: require '======'
if (left || p[0] != '=' || p[1] != '=' || p[2] != '=' || p[3] != '=' || p[4] != '=' || p[5] != '=' || decode32_table[(unsigned char)p[6]] != -1)
*pfInvalid = true;
break;
case 4: // 8n+4 base32 characters processed: require '===='
if (left || p[0] != '=' || p[1] != '=' || p[2] != '=' || p[3] != '=' || decode32_table[(unsigned char)p[4]] != -1)
*pfInvalid = true;
break;
case 5: // 8n+5 base32 characters processed: require '==='
if (left || p[0] != '=' || p[1] != '=' || p[2] != '=' || decode32_table[(unsigned char)p[3]] != -1)
*pfInvalid = true;
break;
case 7: // 8n+7 base32 characters processed: require '='
if (left || p[0] != '=' || decode32_table[(unsigned char)p[1]] != -1)
*pfInvalid = true;
break;
}
return vchRet;
}
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 && val[ptr] >= '0' && val[ptr] <= '9') {
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 && val[ptr] >= '0' && val[ptr] <= '9')
{
while (ptr < end && val[ptr] >= '0' && val[ptr] <= '9') {
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 && val[ptr] >= '0' && val[ptr] <= '9') {
while (ptr < end && val[ptr] >= '0' && val[ptr] <= '9') {
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;
}