esphome/components/nimble_tracker/string_utils.cpp
2023-12-02 12:01:23 +03:00

47 lines
1.4 KiB
C++

// Copied from https://github.com/ESPresense/ESPresense/blob/master/lib/BleFingerprint/string_utils.cpp
#include "string_utils.h"
namespace esphome
{
namespace nimble_tracker
{
static constexpr char hexmap[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
std::string hexStr(const uint8_t *data, int len)
{
std::string s(len * 2, ' ');
for (int i = 0; i < len; ++i)
{
s[2 * i] = hexmap[(data[i] & 0xF0) >> 4];
s[2 * i + 1] = hexmap[data[i] & 0x0F];
}
return s;
}
uint8_t hextob(char ch)
{
if (ch >= '0' && ch <= '9')
return ch - '0';
if (ch >= 'A' && ch <= 'F')
return ch - 'A' + 10;
if (ch >= 'a' && ch <= 'f')
return ch - 'a' + 10;
return 0;
}
bool hextostr(const std::string &hexStr, uint8_t *output, size_t len)
{
if (len & 1)
return false;
if (hexStr.length() < len * 2)
return false;
int k = 0;
for (size_t i = 0; i < len * 2; i += 2)
output[k++] = (hextob(hexStr[i]) << 4) | hextob(hexStr[i + 1]);
return true;
}
} // namespace nimble_tracker
} // namespece esphome