BOLT01: swap CompactSize for BigSize in TLV format #640
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cfromknecht
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I honestly don't have a strong opinion on the endianness we should use.
Keeping Bitcoin's little-endian encoding or switching to big-endian as you propose both seem ok.
I'll let @rustyrussell chime in to decide.
.aspell.en.pws
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It's a bit weird to have to add all of those in the spell-checker...
I think that if we always wrap them in back-ticks (e.g. 0xfc) the spell-checker doesn't look at them, which might be a better solution.
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good point, i gave a shot at modifying the spell checker to ignore code blocks, but not sure that's the best approach
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i'm +1 for ignoring code blocks fwiw
cfromknecht
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This commit modifies the varint encoding used for TLV types and lengths to use a custom format called BigSize. The format is identical to bitcoin's CompactSize, except it replaces the use of little-endian encodings for multi-byte values with big-endian. This is done to prevent mixing endianness within the protocol, since otherwise CompactSize would be the first introduction of little-endian encodings.
cfromknecht
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Ack. We ended up not reusing the Bitcoin routines and reimplementing them for this, so using Bitcoin endianness here was a lose. Wasn't sure if other implementations were the same. JSON for testcases is a bit useless without a programmatic extractor IMHO, but I'm just happy to have test vectors at all. We can have a Grand Testcase Unification later... |
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PS. I've lost count of how many beers I owe @cfromknecht now, but I suspect it may be more than we can drink in Berlin... |
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ACK. Let's decide on this once and for all, big-endian everywhere it is! |
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Tested-Ack: 8038471 |
lightning/bolts#640 Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Based on: lightning/bolts#640 Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Based on: lightning/bolts#640 Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit modifies the varint encoding used for TLV types and lengths
to use a custom format called BigSize. The format is identical to
bitcoin's CompactSize, except it replaces the use of little-endian
encodings for multi-byte values with big-endian. This is done to prevent
mixing endianness within the protocol, since otherwise CompactSize would
be the first introduction of little-endian encodings.