This commit changes the code so that all calls to .Add on waitgroups
happen before the associated goroutines are launched. Doing this after
the goroutine could technically cause a race where the goroutine started
and finished before the main goroutine has a chance to increment the
counter. In our particular case none of the goroutines exit quickly
enough for this to be an issue, but nevertheless the correct way should be
used.
This commit adds support for relaying blocks between peers. It keeps
track of inventory that has either already been advertised to remote peers
or advertised by remote peers using a size-limited most recently used
cache. This helps avoid relaying inventory the peer already knows as
much as possible while not allowing rogue peers to eat up arbitrary
amounts of memory with bogus inventory.
improved error handling
Fix testing, no point in running tests multiple times
Fix error when no blocks in database, reopen would misreport NewstSha() return
Rather than sending the root of the an orphan chain when sending an orphan
notification, send the hash of the orphan block itself. The caller can
then call the GetOrphanRoot function with the hash to get the root of the
orphan chain as needed. This is being changed since it's cleaner and more
detministic sending the hash for the orphan block that was just processed
rather than sending a possibly different hash depending on whether there
is an orphan chain or not.
Since the notification channel is provided by the caller and it may or may
not be buffered, send notifications in their own goroutine so the chain
processing code does not have to wait around on the caller to process the
notification before continuing.
This commit reworks the getblocks handling a bit to clean it up and match
the reference implementation handling. In particular, it adds monitoring
for when peers request the final block advertised from a previous
getblocks message and automatically avertises the latest known block
inventory to trigger the peer to send another getblocks message.
When no blocks in the block locator are found, start with the block after
the genesis block. This means the client will start over with the genesis
block if unknown block locators are provided. This mirrors the behavior
in the reference implementation.
This commit reworks the getheaders handling a bit to clean it up and match
the reference implementation handling. In particular, in addition to the
normal handling where headers starting after the block locator up to the
stop hash are served, when no locator hashes are provided, the stop hash
acts as a way to specifically request that header. Next, an empty headers
message is sent when no hashes provided by the block locator can be
found. Finally, there was a bug that was limiting the number of headers
that could requested at once to 500 instead of the expected 2000.
Rather than only setting the services field for inbound peers, set it for
all peers. This field referes to the remote peer's services regardless of
inbound or outbound.
This commit significantly reworks the fetching code to interop better with
bitcoind. In particular, when an inventory message is sent, and the
remote peer requests the final block, the remote peer sends the current
end of the main chain to signal that there are more blocks to get.
Previously this code was automatically requesting more blocks when the
number of in-flight blocks was under a certain threshold. The original
approach does help alleviate delays in the "request final, wait for
orphan, request more" round trip, but due to the aforementioned mechanism,
it leads to double requests and other subtle issues.
Rather than removing disconnected transactions from the node viewpoint
transaction store, clear the entry instead. This is needed for the
connect code to update transactions that were removed on the other side of
a chain fork.
This commit adds a new type, BlockLocator, and supporting infrastructure
to support generating block locators from a provided hash and getting
a full block locator for the latest known block. This will likely be
expanded in the future to provide the opposite functionality as well.
That is to say the ability to lookup a block using a block locator.
This commit modifies the GenerateInitialIndex function to update the best
chain with each node as it is loaded. This allows the best chain to be
set immediately upon generating the initial index which is a slight
performance optimization.
This commit provides a new exported function, HaveInventory, which can
be used to determine if the already has the item referenced by passed
inventory vector. Currently it only provides support for blocks and
cursory support for transactions in the main chain. Types that are
unrecognized are returned as if they unknown as expected.
This commit provides a new exported function, IsKnownOrphan, which can
be used to determine if the passed hash is currently already known to the
chain as an orphan.
This commit exposes GetOrphanRoot to callers. It also modifies the code
to allow the function to be called in a concurrent safe manner. This
allows the information to be safely obtained from multiple goroutines.
This code is still prototype at this time.
It appears to function correctly but something
consumes more memory than is considered reasonable
for the dataset comprised of the full bitcoind chain.
Not recommened for use at this time.
When running in regression test mode, it is unlikely the user wants to
connect to permanent peers they have configured in their config file.
This commit modifies the code to ignore the config file entry when in
regression test mode. The user can still provide -a (or --addpeer) on the
command line to override this if they really want to connect out to a
specific peer during regression test mode.
It is not safe to remove elements from a slice while iterating them with
the range statement since it does not reevaluate the slice on each
iteration nor does it adjust the index for the modified slice. This
commit modifies the code to use a for loop with an index (which does
reevaluate on every iteration) and manually adjusts the index when
elements are removed from the slice.
This commit modifies the input message handler so that when a remote peer
sends a block, no further messages from that peer are accepted until the
block has been fully processed and therefore known good or bad. This
helps prevent a malicious peer from queueing up a bunch of bad blocks
before disconnecting (or being disconnected) and wasting memory.
Additionally, this behavior is depended on by at least the block
acceptance test tool as the reference implementation processes blocks in
the same thread and therefore blocks further messages until the block has
been fully processed as well.
