// FetchHeightRange looks up a range of blocks by the start and ending
// heights. Fetch is inclusive of the start height and exclusive of the
// ending height. To fetch all hashes from the start height until no
// more are present, use the special id `AllShas'.
func (db *LevelDb) FetchHeightRange(startHeight, endHeight int32) (rshalist []wire.ShaHash, err error) {
db.dbLock.Lock()
defer db.dbLock.Unlock()
var endidx int32
if endHeight == database.AllShas {
endidx = startHeight + 500
} else {
endidx = endHeight
}
shalist := make([]wire.ShaHash, 0, endidx-startHeight)
for height := startHeight; height < endidx; height++ {
// TODO(drahn) fix blkFile from height
key := int64ToKey(int64(height))
blkVal, lerr := db.lDb.Get(key, db.ro)
if lerr != nil {
break
}
var sha wire.ShaHash
sha.SetBytes(blkVal[0:32])
shalist = append(shalist, sha)
}
if err != nil {
return
}
//log.Tracef("FetchIdxRange idx %v %v returned %v shas err %v", startHeight, endHeight, len(shalist), err)
return shalist, nil
}
func parsesha(argstr string) (argtype int, height int32, psha *wire.ShaHash, err error) {
var sha wire.ShaHash
var hashbuf string
switch len(argstr) {
case 64:
hashbuf = argstr
case 66:
if argstr[0:2] != "0x" {
log.Infof("prefix is %v", argstr[0:2])
err = errBadShaPrefix
return
}
hashbuf = argstr[2:]
default:
if len(argstr) <= 16 {
// assume value is height
argtype = argHeight
var h int
h, err = strconv.Atoi(argstr)
if err == nil {
height = int32(h)
return
}
log.Infof("Unable to parse height %v, err %v", height, err)
}
err = errBadShaLen
return
}
var buf [32]byte
for idx, ch := range hashbuf {
var val rune
switch {
case ch >= '0' && ch <= '9':
val = ch - '0'
case ch >= 'a' && ch <= 'f':
val = ch - 'a' + rune(10)
case ch >= 'A' && ch <= 'F':
val = ch - 'A' + rune(10)
default:
err = errBadShaChar
return
}
b := buf[31-idx/2]
if idx&1 == 1 {
b |= byte(val)
} else {
b |= (byte(val) << 4)
}
buf[31-idx/2] = b
}
sha.SetBytes(buf[0:32])
psha = &sha
return
}
func assertAddrIndexTipIsUpdated(db database.Db, t *testing.T, newestSha *wire.ShaHash, newestBlockIdx int32) {
// Safe to ignore error, since height will be < 0 in "error" case.
sha, height, _ := db.FetchAddrIndexTip()
if newestBlockIdx != height {
t.Fatalf("Height of address index tip failed to update, "+
"expected %v, got %v", newestBlockIdx, height)
}
if !bytes.Equal(newestSha.Bytes(), sha.Bytes()) {
t.Fatalf("Sha of address index tip failed to update, "+
"expected %v, got %v", newestSha, sha)
}
}
// fetchBlockShaByHeight returns a block hash based on its height in the
// block chain.
func (db *LevelDb) fetchBlockShaByHeight(height int32) (rsha *wire.ShaHash, err error) {
key := int64ToKey(int64(height))
blkVal, err := db.lDb.Get(key, db.ro)
if err != nil {
log.Tracef("failed to find height %v", height)
return // exists ???
}
var sha wire.ShaHash
sha.SetBytes(blkVal[0:32])
return &sha, nil
}
// fetchAddrIndexTip returns the last block height and block sha to be indexed.
// Meta-data about the address tip is currently cached in memory, and will be
// updated accordingly by functions that modify the state. This function is
// used on start up to load the info into memory. Callers will use the public
// version of this function below, which returns our cached copy.
func (db *LevelDb) fetchAddrIndexTip() (*wire.ShaHash, int32, error) {
db.dbLock.Lock()
defer db.dbLock.Unlock()
data, err := db.lDb.Get(addrIndexMetaDataKey, db.ro)
if err != nil {
return &wire.ShaHash{}, -1, database.ErrAddrIndexDoesNotExist
}
var blkSha wire.ShaHash
blkSha.SetBytes(data[0:32])
blkHeight := binary.LittleEndian.Uint64(data[32:])
return &blkSha, int32(blkHeight), nil
}
func (db *LevelDb) getBlkByHeight(blkHeight int32) (rsha *wire.ShaHash, rbuf []byte, err error) {
var blkVal []byte
key := int64ToKey(int64(blkHeight))
blkVal, err = db.lDb.Get(key, db.ro)
if err != nil {
log.Tracef("failed to find height %v", blkHeight)
return // exists ???
}
var sha wire.ShaHash
sha.SetBytes(blkVal[0:32])
blockdata := make([]byte, len(blkVal[32:]))
copy(blockdata[:], blkVal[32:])
return &sha, blockdata, nil
}
// BlockLocatorFromHash returns a block locator for the passed block hash.
// See BlockLocator for details on the algotirhm used to create a block locator.
//
// In addition to the general algorithm referenced above, there are a couple of
// special cases which are handled:
//
// - If the genesis hash is passed, there are no previous hashes to add and
// therefore the block locator will only consist of the genesis hash
// - If the passed hash is not currently known, the block locator will only
// consist of the passed hash
func (b *BlockChain) BlockLocatorFromHash(hash *wire.ShaHash) BlockLocator {
// The locator contains the requested hash at the very least.
locator := make(BlockLocator, 0, wire.MaxBlockLocatorsPerMsg)
locator = append(locator, hash)
// Nothing more to do if a locator for the genesis hash was requested.
if hash.IsEqual(b.chainParams.GenesisHash) {
return locator
}
// Attempt to find the height of the block that corresponds to the
// passed hash, and if it's on a side chain, also find the height at
// which it forks from the main chain.
blockHeight := int32(-1)
forkHeight := int32(-1)
node, exists := b.index[*hash]
if !exists {
// Try to look up the height for passed block hash. Assume an
// error means it doesn't exist and just return the locator for
// the block itself.
height, err := b.db.FetchBlockHeightBySha(hash)
if err != nil {
return locator
}
blockHeight = height
} else {
blockHeight = node.height
// Find the height at which this node forks from the main chain
// if the node is on a side chain.
if !node.inMainChain {
for n := node; n.parent != nil; n = n.parent {
if n.inMainChain {
forkHeight = n.height
break
}
}
}
}
// Generate the block locators according to the algorithm described in
// in the BlockLocator comment and make sure to leave room for the
// final genesis hash.
iterNode := node
increment := int32(1)
for len(locator) < wire.MaxBlockLocatorsPerMsg-1 {
// Once there are 10 locators, exponentially increase the
// distance between each block locator.
if len(locator) > 10 {
increment *= 2
}
blockHeight -= increment
if blockHeight < 1 {
break
}
// As long as this is still on the side chain, walk backwards
// along the side chain nodes to each block height.
if forkHeight != -1 && blockHeight > forkHeight {
// Intentionally use parent field instead of the
// getPrevNodeFromNode function since we don't want to
// dynamically load nodes when building block locators.
// Side chain blocks should always be in memory already,
// and if they aren't for some reason it's ok to skip
// them.
for iterNode != nil && blockHeight > iterNode.height {
iterNode = iterNode.parent
}
if iterNode != nil && iterNode.height == blockHeight {
locator = append(locator, iterNode.hash)
}
continue
}
// The desired block height is in the main chain, so look it up
// from the main chain database.
h, err := b.db.FetchBlockShaByHeight(blockHeight)
if err != nil {
// This shouldn't happen and it's ok to ignore block
// locators, so just continue to the next one.
log.Warnf("Lookup of known valid height failed %v",
blockHeight)
continue
}
locator = append(locator, h)
}
// Append the appropriate genesis block.
locator = append(locator, b.chainParams.GenesisHash)
return locator
}