bsnes/nall/string/utility.hpp

118 lines
2.6 KiB
C++

#ifdef NALL_STRING_INTERNAL_HPP
namespace nall {
string substr(rstring source, unsigned offset, unsigned length) {
string result;
if(length == ~0u) length = source.size() - offset;
result.resize(length);
memcpy(result.data(), source.data() + offset, length);
return result;
}
string sha256(const uint8_t* data, unsigned size) {
sha256_ctx sha;
uint8_t hash[32];
sha256_init(&sha);
sha256_chunk(&sha, data, size);
sha256_final(&sha);
sha256_hash(&sha, hash);
string result;
for(auto& byte : hash) result.append(hex<2>(byte));
return result;
}
bool tokenize(lstring& list, const char* s, const char* p) {
while(*s) {
if(*p == '*') {
const char* b = s;
while(*s) {
if(tokenize(list, s++, p + 1)) {
list.prepend(substr(b, 0, --s - b));
return true;
}
}
list.prepend(b);
return !*++p;
}
if(*s++ != *p++) return false;
}
while(*p == '*') { list.prepend(s); p++; }
return !*p;
}
char* integer(char* result, intmax_t value) {
bool negative = value < 0;
if(negative) value = -value;
char buffer[64];
unsigned size = 0;
do {
unsigned n = value % 10;
buffer[size++] = '0' + n;
value /= 10;
} while(value);
if(negative) buffer[size++] = '-';
//buffer[size++] = negative ? '-' : '+';
for(signed x = size - 1, y = 0; x >= 0 && y < size; x--, y++) result[x] = buffer[y];
result[size] = 0;
return result;
}
char* decimal(char* result, uintmax_t value) {
char buffer[64];
unsigned size = 0;
do {
unsigned n = value % 10;
buffer[size++] = '0' + n;
value /= 10;
} while(value);
for(signed x = size - 1, y = 0; x >= 0 && y < size; x--, y++) result[x] = buffer[y];
result[size] = 0;
return result;
}
//using sprintf is certainly not the most ideal method to convert
//a double to a string ... but attempting to parse a double by
//hand, digit-by-digit, results in subtle rounding errors.
unsigned real(char* str, long double value) {
char buffer[256];
#ifdef _WIN32
//Windows C-runtime does not support long double via sprintf()
sprintf(buffer, "%f", (double)value);
#else
sprintf(buffer, "%Lf", value);
#endif
//remove excess 0's in fraction (2.500000 -> 2.5)
for(char* p = buffer; *p; p++) {
if(*p == '.') {
char* p = buffer + strlen(buffer) - 1;
while(*p == '0') {
if(*(p - 1) != '.') *p = 0; //... but not for eg 1.0 -> 1.
p--;
}
break;
}
}
unsigned length = strlen(buffer);
if(str) strcpy(str, buffer);
return length + 1;
}
string real(long double value) {
string temp;
temp.resize(real(nullptr, value));
real(temp.data(), value);
return temp;
}
}
#endif