/**
* @brief Return a copy of str, converting each escaped "%XX" to the char value
*/
inline std::string
unescape(const std::string& str)
{
std::ostringstream result;
for (size_t i = 0; i < str.size(); ++i) {
if (str[i] == '%' && i + 2 < str.size()) {
int hi = fromHexChar(str[i + 1]);
int lo = fromHexChar(str[i + 2]);
if (hi < 0 || lo < 0)
// Invalid hex characters, so just keep the escaped string.
result << str[i] << str[i + 1] << str[i + 2];
else
result << (uint8_t)(16 * hi + lo);
// Skip ahead past the escaped value.
i += 2;
}
else
// Just copy through.
result << str[i];
}
return result.str();
}
/**
* Convert the hex string to bytes and call SHA256_Update.
* @param context The SHA256_CTX to update.
* @param hex The hex string.
* @return The result from SHA256_Update.
*/
static int
SHA256_UpdateHex(SHA256_CTX *context, const string& hex)
{
vector<uint8_t> data(hex.size() / 2);
for (size_t i = 0; i < data.size(); ++i)
data[i] = (uint8_t)(16 * fromHexChar(hex[2 * i]) + fromHexChar(hex[2 * i + 1]));
return SHA256_Update(context, &data[0], data.size());
}
