Protobuf pattern does not support field numbers > 15

[prosenkranz]

As per Protobuf Documentation, "Tags" (Keys) of Records/Keys are encoded as VarInts / LEB128.

However the current Protobuf pattern assumes Keys are always 1 byte:

ImHex-Patterns/patterns/protobuf.hexpat

Line 34 in 6baae92

} [[bitfield_order(std::core::BitfieldOrder::MostToLeastSignificant, 8)]];

This assumption will not work anymore for larger (>15) field numbers, where the varint will be 2 bytes long:

CodedOutputStream stream = ...;
stream.writeUInt(16, 0);

The output binary will be:

80 01 00

The value byte here is expected to be 0. The current pattern will incorrectly interpret the second byte as the value 1.

[jumanji144]

This can be solved by replacing the bitfield with a uleb128 and logical bit shifts