1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2020 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 #include <util/strencodings.h>
7 #include <util/string.h>
8
9 #include <tinyformat.h>
10
11 #include <algorithm>
12 #include <cstdlib>
13 #include <cstring>
14 #include <errno.h>
15 #include <limits>
16
17 static const std::string CHARS_ALPHA_NUM = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
18
19 static const std::string SAFE_CHARS[] =
20 {
21 CHARS_ALPHA_NUM + " .,;-_/:?@()", // SAFE_CHARS_DEFAULT
22 CHARS_ALPHA_NUM + " .,;-_?@", // SAFE_CHARS_UA_COMMENT
23 CHARS_ALPHA_NUM + ".-_", // SAFE_CHARS_FILENAME
24 CHARS_ALPHA_NUM + "!*'();:@&=+$,/?#[]-_.~%", // SAFE_CHARS_URI
25 };
26
SanitizeString(const std::string & str,int rule)27 std::string SanitizeString(const std::string& str, int rule)
28 {
29 std::string strResult;
30 for (std::string::size_type i = 0; i < str.size(); i++)
31 {
32 if (SAFE_CHARS[rule].find(str[i]) != std::string::npos)
33 strResult.push_back(str[i]);
34 }
35 return strResult;
36 }
37
38 const signed char p_util_hexdigit[256] =
39 { -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
40 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
41 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
42 0,1,2,3,4,5,6,7,8,9,-1,-1,-1,-1,-1,-1,
43 -1,0xa,0xb,0xc,0xd,0xe,0xf,-1,-1,-1,-1,-1,-1,-1,-1,-1,
44 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
45 -1,0xa,0xb,0xc,0xd,0xe,0xf,-1,-1,-1,-1,-1,-1,-1,-1,-1,
46 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
47 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
48 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
49 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
50 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
51 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
52 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
53 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
54 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, };
55
HexDigit(char c)56 signed char HexDigit(char c)
57 {
58 return p_util_hexdigit[(unsigned char)c];
59 }
60
IsHex(const std::string & str)61 bool IsHex(const std::string& str)
62 {
63 for(std::string::const_iterator it(str.begin()); it != str.end(); ++it)
64 {
65 if (HexDigit(*it) < 0)
66 return false;
67 }
68 return (str.size() > 0) && (str.size()%2 == 0);
69 }
70
IsHexNumber(const std::string & str)71 bool IsHexNumber(const std::string& str)
72 {
73 size_t starting_location = 0;
74 if (str.size() > 2 && *str.begin() == '0' && *(str.begin()+1) == 'x') {
75 starting_location = 2;
76 }
77 for (const char c : str.substr(starting_location)) {
78 if (HexDigit(c) < 0) return false;
79 }
80 // Return false for empty string or "0x".
81 return (str.size() > starting_location);
82 }
83
ParseHex(const char * psz)84 std::vector<unsigned char> ParseHex(const char* psz)
85 {
86 // convert hex dump to vector
87 std::vector<unsigned char> vch;
88 while (true)
89 {
90 while (IsSpace(*psz))
91 psz++;
92 signed char c = HexDigit(*psz++);
93 if (c == (signed char)-1)
94 break;
95 unsigned char n = (c << 4);
96 c = HexDigit(*psz++);
97 if (c == (signed char)-1)
98 break;
99 n |= c;
100 vch.push_back(n);
101 }
102 return vch;
103 }
104
ParseHex(const std::string & str)105 std::vector<unsigned char> ParseHex(const std::string& str)
106 {
107 return ParseHex(str.c_str());
108 }
109
SplitHostPort(std::string in,uint16_t & portOut,std::string & hostOut)110 void SplitHostPort(std::string in, uint16_t& portOut, std::string& hostOut)
111 {
112 size_t colon = in.find_last_of(':');
113 // if a : is found, and it either follows a [...], or no other : is in the string, treat it as port separator
114 bool fHaveColon = colon != in.npos;
115 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
116 bool fMultiColon = fHaveColon && (in.find_last_of(':', colon - 1) != in.npos);
117 if (fHaveColon && (colon == 0 || fBracketed || !fMultiColon)) {
118 uint16_t n;
119 if (ParseUInt16(in.substr(colon + 1), &n)) {
120 in = in.substr(0, colon);
121 portOut = n;
122 }
123 }
124 if (in.size() > 0 && in[0] == '[' && in[in.size() - 1] == ']') {
125 hostOut = in.substr(1, in.size() - 2);
126 } else {
127 hostOut = in;
128 }
129 }
130
EncodeBase64(Span<const unsigned char> input)131 std::string EncodeBase64(Span<const unsigned char> input)
132 {
133 static const char *pbase64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
134
135 std::string str;
136 str.reserve(((input.size() + 2) / 3) * 4);
137 ConvertBits<8, 6, true>([&](int v) { str += pbase64[v]; }, input.begin(), input.end());
138 while (str.size() % 4) str += '=';
139 return str;
140 }
141
EncodeBase64(const std::string & str)142 std::string EncodeBase64(const std::string& str)
143 {
144 return EncodeBase64(MakeUCharSpan(str));
145 }
146
DecodeBase64(const char * p,bool * pf_invalid)147 std::vector<unsigned char> DecodeBase64(const char* p, bool* pf_invalid)
148 {
149 static const int decode64_table[256] =
150 {
151 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
152 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
153 -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1,
154 -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
155 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28,
156 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
157 49, 50, 51, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
158 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
159 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
160 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
161 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
162 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
163 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
164 };
165
166 const char* e = p;
167 std::vector<uint8_t> val;
168 val.reserve(strlen(p));
169 while (*p != 0) {
170 int x = decode64_table[(unsigned char)*p];
171 if (x == -1) break;
172 val.push_back(x);
173 ++p;
174 }
175
176 std::vector<unsigned char> ret;
177 ret.reserve((val.size() * 3) / 4);
178 bool valid = ConvertBits<6, 8, false>([&](unsigned char c) { ret.push_back(c); }, val.begin(), val.end());
179
180 const char* q = p;
181 while (valid && *p != 0) {
182 if (*p != '=') {
183 valid = false;
184 break;
185 }
186 ++p;
187 }
188 valid = valid && (p - e) % 4 == 0 && p - q < 4;
189 if (pf_invalid) *pf_invalid = !valid;
190
191 return ret;
192 }
193
DecodeBase64(const std::string & str,bool * pf_invalid)194 std::string DecodeBase64(const std::string& str, bool* pf_invalid)
195 {
196 if (!ValidAsCString(str)) {
197 if (pf_invalid) {
198 *pf_invalid = true;
199 }
200 return {};
201 }
202 std::vector<unsigned char> vchRet = DecodeBase64(str.c_str(), pf_invalid);
203 return std::string((const char*)vchRet.data(), vchRet.size());
204 }
205
EncodeBase32(Span<const unsigned char> input,bool pad)206 std::string EncodeBase32(Span<const unsigned char> input, bool pad)
207 {
208 static const char *pbase32 = "abcdefghijklmnopqrstuvwxyz234567";
209
210 std::string str;
211 str.reserve(((input.size() + 4) / 5) * 8);
212 ConvertBits<8, 5, true>([&](int v) { str += pbase32[v]; }, input.begin(), input.end());
213 if (pad) {
214 while (str.size() % 8) {
215 str += '=';
216 }
217 }
218 return str;
219 }
220
EncodeBase32(const std::string & str,bool pad)221 std::string EncodeBase32(const std::string& str, bool pad)
222 {
223 return EncodeBase32(MakeUCharSpan(str), pad);
224 }
225
DecodeBase32(const char * p,bool * pf_invalid)226 std::vector<unsigned char> DecodeBase32(const char* p, bool* pf_invalid)
227 {
228 static const int decode32_table[256] =
229 {
230 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
231 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
232 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, -1, -1, -1, -1,
233 -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
234 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 0, 1, 2,
235 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
236 23, 24, 25, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
237 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
238 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
239 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
240 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
241 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
242 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
243 };
244
245 const char* e = p;
246 std::vector<uint8_t> val;
247 val.reserve(strlen(p));
248 while (*p != 0) {
249 int x = decode32_table[(unsigned char)*p];
250 if (x == -1) break;
251 val.push_back(x);
252 ++p;
253 }
254
255 std::vector<unsigned char> ret;
256 ret.reserve((val.size() * 5) / 8);
257 bool valid = ConvertBits<5, 8, false>([&](unsigned char c) { ret.push_back(c); }, val.begin(), val.end());
258
259 const char* q = p;
260 while (valid && *p != 0) {
261 if (*p != '=') {
262 valid = false;
263 break;
264 }
265 ++p;
266 }
267 valid = valid && (p - e) % 8 == 0 && p - q < 8;
268 if (pf_invalid) *pf_invalid = !valid;
269
270 return ret;
271 }
272
DecodeBase32(const std::string & str,bool * pf_invalid)273 std::string DecodeBase32(const std::string& str, bool* pf_invalid)
274 {
275 if (!ValidAsCString(str)) {
276 if (pf_invalid) {
277 *pf_invalid = true;
278 }
279 return {};
280 }
281 std::vector<unsigned char> vchRet = DecodeBase32(str.c_str(), pf_invalid);
282 return std::string((const char*)vchRet.data(), vchRet.size());
283 }
284
ParsePrechecks(const std::string & str)285 [[nodiscard]] static bool ParsePrechecks(const std::string& str)
286 {
287 if (str.empty()) // No empty string allowed
288 return false;
289 if (str.size() >= 1 && (IsSpace(str[0]) || IsSpace(str[str.size()-1]))) // No padding allowed
290 return false;
291 if (!ValidAsCString(str)) // No embedded NUL characters allowed
292 return false;
293 return true;
294 }
295
ParseInt32(const std::string & str,int32_t * out)296 bool ParseInt32(const std::string& str, int32_t *out)
297 {
298 if (!ParsePrechecks(str))
299 return false;
300 char *endp = nullptr;
301 errno = 0; // strtol will not set errno if valid
302 long int n = strtol(str.c_str(), &endp, 10);
303 if(out) *out = (int32_t)n;
304 // Note that strtol returns a *long int*, so even if strtol doesn't report an over/underflow
305 // we still have to check that the returned value is within the range of an *int32_t*. On 64-bit
306 // platforms the size of these types may be different.
307 return endp && *endp == 0 && !errno &&
308 n >= std::numeric_limits<int32_t>::min() &&
309 n <= std::numeric_limits<int32_t>::max();
310 }
311
ParseInt64(const std::string & str,int64_t * out)312 bool ParseInt64(const std::string& str, int64_t *out)
313 {
314 if (!ParsePrechecks(str))
315 return false;
316 char *endp = nullptr;
317 errno = 0; // strtoll will not set errno if valid
318 long long int n = strtoll(str.c_str(), &endp, 10);
319 if(out) *out = (int64_t)n;
320 // Note that strtoll returns a *long long int*, so even if strtol doesn't report an over/underflow
321 // we still have to check that the returned value is within the range of an *int64_t*.
322 return endp && *endp == 0 && !errno &&
323 n >= std::numeric_limits<int64_t>::min() &&
324 n <= std::numeric_limits<int64_t>::max();
325 }
326
ParseUInt8(const std::string & str,uint8_t * out)327 bool ParseUInt8(const std::string& str, uint8_t *out)
328 {
329 uint32_t u32;
330 if (!ParseUInt32(str, &u32) || u32 > std::numeric_limits<uint8_t>::max()) {
331 return false;
332 }
333 if (out != nullptr) {
334 *out = static_cast<uint8_t>(u32);
335 }
336 return true;
337 }
338
ParseUInt16(const std::string & str,uint16_t * out)339 bool ParseUInt16(const std::string& str, uint16_t* out)
340 {
341 uint32_t u32;
342 if (!ParseUInt32(str, &u32) || u32 > std::numeric_limits<uint16_t>::max()) {
343 return false;
344 }
345 if (out != nullptr) {
346 *out = static_cast<uint16_t>(u32);
347 }
348 return true;
349 }
350
ParseUInt32(const std::string & str,uint32_t * out)351 bool ParseUInt32(const std::string& str, uint32_t *out)
352 {
353 if (!ParsePrechecks(str))
354 return false;
355 if (str.size() >= 1 && str[0] == '-') // Reject negative values, unfortunately strtoul accepts these by default if they fit in the range
356 return false;
357 char *endp = nullptr;
358 errno = 0; // strtoul will not set errno if valid
359 unsigned long int n = strtoul(str.c_str(), &endp, 10);
360 if(out) *out = (uint32_t)n;
361 // Note that strtoul returns a *unsigned long int*, so even if it doesn't report an over/underflow
362 // we still have to check that the returned value is within the range of an *uint32_t*. On 64-bit
363 // platforms the size of these types may be different.
364 return endp && *endp == 0 && !errno &&
365 n <= std::numeric_limits<uint32_t>::max();
366 }
367
ParseUInt64(const std::string & str,uint64_t * out)368 bool ParseUInt64(const std::string& str, uint64_t *out)
369 {
370 if (!ParsePrechecks(str))
371 return false;
372 if (str.size() >= 1 && str[0] == '-') // Reject negative values, unfortunately strtoull accepts these by default if they fit in the range
373 return false;
374 char *endp = nullptr;
375 errno = 0; // strtoull will not set errno if valid
376 unsigned long long int n = strtoull(str.c_str(), &endp, 10);
377 if(out) *out = (uint64_t)n;
378 // Note that strtoull returns a *unsigned long long int*, so even if it doesn't report an over/underflow
379 // we still have to check that the returned value is within the range of an *uint64_t*.
380 return endp && *endp == 0 && !errno &&
381 n <= std::numeric_limits<uint64_t>::max();
382 }
383
384
ParseDouble(const std::string & str,double * out)385 bool ParseDouble(const std::string& str, double *out)
386 {
387 if (!ParsePrechecks(str))
388 return false;
389 if (str.size() >= 2 && str[0] == '0' && str[1] == 'x') // No hexadecimal floats allowed
390 return false;
391 std::istringstream text(str);
392 text.imbue(std::locale::classic());
393 double result;
394 text >> result;
395 if(out) *out = result;
396 return text.eof() && !text.fail();
397 }
398
FormatParagraph(const std::string & in,size_t width,size_t indent)399 std::string FormatParagraph(const std::string& in, size_t width, size_t indent)
400 {
401 std::stringstream out;
402 size_t ptr = 0;
403 size_t indented = 0;
404 while (ptr < in.size())
405 {
406 size_t lineend = in.find_first_of('\n', ptr);
407 if (lineend == std::string::npos) {
408 lineend = in.size();
409 }
410 const size_t linelen = lineend - ptr;
411 const size_t rem_width = width - indented;
412 if (linelen <= rem_width) {
413 out << in.substr(ptr, linelen + 1);
414 ptr = lineend + 1;
415 indented = 0;
416 } else {
417 size_t finalspace = in.find_last_of(" \n", ptr + rem_width);
418 if (finalspace == std::string::npos || finalspace < ptr) {
419 // No place to break; just include the entire word and move on
420 finalspace = in.find_first_of("\n ", ptr);
421 if (finalspace == std::string::npos) {
422 // End of the string, just add it and break
423 out << in.substr(ptr);
424 break;
425 }
426 }
427 out << in.substr(ptr, finalspace - ptr) << "\n";
428 if (in[finalspace] == '\n') {
429 indented = 0;
430 } else if (indent) {
431 out << std::string(indent, ' ');
432 indented = indent;
433 }
434 ptr = finalspace + 1;
435 }
436 }
437 return out.str();
438 }
439
atoi64(const std::string & str)440 int64_t atoi64(const std::string& str)
441 {
442 #ifdef _MSC_VER
443 return _atoi64(str.c_str());
444 #else
445 return strtoll(str.c_str(), nullptr, 10);
446 #endif
447 }
448
atoi(const std::string & str)449 int atoi(const std::string& str)
450 {
451 return atoi(str.c_str());
452 }
453
454 /** Upper bound for mantissa.
455 * 10^18-1 is the largest arbitrary decimal that will fit in a signed 64-bit integer.
456 * Larger integers cannot consist of arbitrary combinations of 0-9:
457 *
458 * 999999999999999999 1^18-1
459 * 9223372036854775807 (1<<63)-1 (max int64_t)
460 * 9999999999999999999 1^19-1 (would overflow)
461 */
462 static const int64_t UPPER_BOUND = 1000000000000000000LL - 1LL;
463
464 /** Helper function for ParseFixedPoint */
ProcessMantissaDigit(char ch,int64_t & mantissa,int & mantissa_tzeros)465 static inline bool ProcessMantissaDigit(char ch, int64_t &mantissa, int &mantissa_tzeros)
466 {
467 if(ch == '0')
468 ++mantissa_tzeros;
469 else {
470 for (int i=0; i<=mantissa_tzeros; ++i) {
471 if (mantissa > (UPPER_BOUND / 10LL))
472 return false; /* overflow */
473 mantissa *= 10;
474 }
475 mantissa += ch - '0';
476 mantissa_tzeros = 0;
477 }
478 return true;
479 }
480
ParseFixedPoint(const std::string & val,int decimals,int64_t * amount_out)481 bool ParseFixedPoint(const std::string &val, int decimals, int64_t *amount_out)
482 {
483 int64_t mantissa = 0;
484 int64_t exponent = 0;
485 int mantissa_tzeros = 0;
486 bool mantissa_sign = false;
487 bool exponent_sign = false;
488 int ptr = 0;
489 int end = val.size();
490 int point_ofs = 0;
491
492 if (ptr < end && val[ptr] == '-') {
493 mantissa_sign = true;
494 ++ptr;
495 }
496 if (ptr < end)
497 {
498 if (val[ptr] == '0') {
499 /* pass single 0 */
500 ++ptr;
501 } else if (val[ptr] >= '1' && val[ptr] <= '9') {
502 while (ptr < end && IsDigit(val[ptr])) {
503 if (!ProcessMantissaDigit(val[ptr], mantissa, mantissa_tzeros))
504 return false; /* overflow */
505 ++ptr;
506 }
507 } else return false; /* missing expected digit */
508 } else return false; /* empty string or loose '-' */
509 if (ptr < end && val[ptr] == '.')
510 {
511 ++ptr;
512 if (ptr < end && IsDigit(val[ptr]))
513 {
514 while (ptr < end && IsDigit(val[ptr])) {
515 if (!ProcessMantissaDigit(val[ptr], mantissa, mantissa_tzeros))
516 return false; /* overflow */
517 ++ptr;
518 ++point_ofs;
519 }
520 } else return false; /* missing expected digit */
521 }
522 if (ptr < end && (val[ptr] == 'e' || val[ptr] == 'E'))
523 {
524 ++ptr;
525 if (ptr < end && val[ptr] == '+')
526 ++ptr;
527 else if (ptr < end && val[ptr] == '-') {
528 exponent_sign = true;
529 ++ptr;
530 }
531 if (ptr < end && IsDigit(val[ptr])) {
532 while (ptr < end && IsDigit(val[ptr])) {
533 if (exponent > (UPPER_BOUND / 10LL))
534 return false; /* overflow */
535 exponent = exponent * 10 + val[ptr] - '0';
536 ++ptr;
537 }
538 } else return false; /* missing expected digit */
539 }
540 if (ptr != end)
541 return false; /* trailing garbage */
542
543 /* finalize exponent */
544 if (exponent_sign)
545 exponent = -exponent;
546 exponent = exponent - point_ofs + mantissa_tzeros;
547
548 /* finalize mantissa */
549 if (mantissa_sign)
550 mantissa = -mantissa;
551
552 /* convert to one 64-bit fixed-point value */
553 exponent += decimals;
554 if (exponent < 0)
555 return false; /* cannot represent values smaller than 10^-decimals */
556 if (exponent >= 18)
557 return false; /* cannot represent values larger than or equal to 10^(18-decimals) */
558
559 for (int i=0; i < exponent; ++i) {
560 if (mantissa > (UPPER_BOUND / 10LL) || mantissa < -(UPPER_BOUND / 10LL))
561 return false; /* overflow */
562 mantissa *= 10;
563 }
564 if (mantissa > UPPER_BOUND || mantissa < -UPPER_BOUND)
565 return false; /* overflow */
566
567 if (amount_out)
568 *amount_out = mantissa;
569
570 return true;
571 }
572
ToLower(const std::string & str)573 std::string ToLower(const std::string& str)
574 {
575 std::string r;
576 for (auto ch : str) r += ToLower((unsigned char)ch);
577 return r;
578 }
579
ToUpper(const std::string & str)580 std::string ToUpper(const std::string& str)
581 {
582 std::string r;
583 for (auto ch : str) r += ToUpper((unsigned char)ch);
584 return r;
585 }
586
Capitalize(std::string str)587 std::string Capitalize(std::string str)
588 {
589 if (str.empty()) return str;
590 str[0] = ToUpper(str.front());
591 return str;
592 }
593
HexStr(const Span<const uint8_t> s)594 std::string HexStr(const Span<const uint8_t> s)
595 {
596 std::string rv(s.size() * 2, '\0');
597 static constexpr char hexmap[16] = { '0', '1', '2', '3', '4', '5', '6', '7',
598 '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
599 auto it = rv.begin();
600 for (uint8_t v : s) {
601 *it++ = hexmap[v >> 4];
602 *it++ = hexmap[v & 15];
603 }
604 assert(it == rv.end());
605 return rv;
606 }
607