Fix 24 bit signed integer parsing in sml parser (#5250)

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mulder-fbi 2023-08-16 00:52:56 +02:00 committed by Jesse Hills
parent afd26c6f1a
commit ff8a73c2d1
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@ -88,6 +88,11 @@ uint64_t bytes_to_uint(const bytes &buffer) {
for (auto const value : buffer) {
val = (val << 8) + value;
}
// Some smart meters send 24 bit signed integers. Sign extend to 64 bit if the
// 24 bit value is negative.
if (buffer.size() == 3 && buffer[0] & 0x80) {
val |= 0xFFFFFFFFFF000000;
}
return val;
}