Update libsnark
We have now forked libsnark's current master and applied the following patches:
* [`9216072`: Remove code that we don't use.](9216072c3b) (unblocks #69)
* [`dcb78b2`: Modify makefile to stop compiling things we removed.](dcb78b24d9)
* [`a6b0ad0`: Use libsodium's PRNG](a6b0ad0c80) (closes#780)
* [`4036716`: Don't (de)serialize the constraint system in the proving key.](403671675a) (closes#491)
* [`a703148`: Taylor's compilation patch](a7031481fd) (@defuse can you submit this to upstream?)
This PR adopts those changes, and makes the requisite changes to Zcash to support them. I have decided to not bring libsnark in tree for the time being, though it should be incredibly easy to do later if we're *absolutely* sure we should.
Add getblocksubsidy RPC command to return block reward taking into account mining slow start
This PR adds a new RPC command to return the block reward as defined by function `GetBlockSubsidy`.
Usage:
`zcash-cli getblocksubsidy blockheight
`
The basis for this PR is that some users have been unaware of the mining slow start and they subsequently sought help to clarify if they were mining blocks correctly or if there was a bug in the reward schedule.
Flush to disk more consistently by accounting memory usage of serials/anchors in cache.
Closes#626.
It's important that this at least *approximates* the memory usage, so that we flush the cache to disk as expected. It's okay that we overestimate. The serials are stored in keys in the `boost::unordered_map`, so we can simply use that map's `DynamicMemoryUsage`. The anchors are another story.
Only compare the first n/(k+1) bits when sorting
We only need to sort based on the bits we are colliding. In earlier solver rounds, this speeds up the comparison considerably (calling `memcmp()` on 3 bytes instead of 12 in the first round for the current parameters).
Randomise the nonce in the block header
The top and bottom 16 bits of the nonce are left clear for local use as thread
flags and counters. This does not leak any more local information about the
miner than is currently exposed.
The cleared bits should not be considered a consensus rule, as miners are free
to set all bits of the nonce however they wish.
Closes#1033
The top and bottom 16 bits of the nonce are left clear for local use as thread
flags and counters. This does not leak any more local information about the
miner than is currently exposed.
The cleared bits should not be considered a consensus rule, as miners are free
to set all bits of the nonce however they wish.
Closes#1033
