107 lines
2.6 KiB
Go
107 lines
2.6 KiB
Go
package store
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// import (
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// "encoding/binary"
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// sdk "github.com/cosmos/cosmos-sdk"
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// )
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// var (
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// headKey = []byte("h")
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// tailKey = []byte("t")
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// dataKey = []byte("d")
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// )
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// // QueueHeadKey gives us the key for the height at head of the queue
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// func QueueHeadKey() []byte {
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// return headKey
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// }
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// // QueueTailKey gives us the key for the height at tail of the queue
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// func QueueTailKey() []byte {
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// return tailKey
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// }
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// // QueueItemKey gives us the key to look up one item by sequence
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// func QueueItemKey(i uint64) []byte {
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// return makeKey(i)
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// }
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// // Queue allows us to fill up a range of the db, and grab from either end
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// type Queue struct {
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// store sdk.KVStore
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// head uint64 // if Size() > 0, the first element is here
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// tail uint64 // this is the first empty slot to Push() to
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// }
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// // NewQueue will load or initialize a queue in this state-space
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// //
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// // Generally, you will want to stack.PrefixStore() the space first
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// func NewQueue(store sdk.KVStore) *Queue {
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// q := &Queue{store: store}
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// q.head = q.getCount(headKey)
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// q.tail = q.getCount(tailKey)
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// return q
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// }
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// // Tail returns the next slot that Push() will use
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// func (q *Queue) Tail() uint64 {
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// return q.tail
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// }
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// // Size returns how many elements are in the queue
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// func (q *Queue) Size() int {
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// return int(q.tail - q.head)
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// }
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// // Push adds an element to the tail of the queue and returns it's location
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// func (q *Queue) Push(value []byte) uint64 {
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// key := makeKey(q.tail)
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// q.store.Set(key, value)
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// q.tail++
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// q.setCount(tailKey, q.tail)
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// return q.tail - 1
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// }
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// // Pop gets an element from the end of the queue
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// func (q *Queue) Pop() []byte {
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// if q.Size() <= 0 {
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// return nil
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// }
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// key := makeKey(q.head)
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// value := q.store.Get(key)
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// q.head++
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// q.setCount(headKey, q.head)
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// return value
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// }
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// // Item looks at any element in the queue, without modifying anything
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// func (q *Queue) Item(seq uint64) []byte {
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// if seq >= q.tail || seq < q.head {
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// return nil
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// }
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// return q.store.Get(makeKey(seq))
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// }
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// func (q *Queue) setCount(key []byte, val uint64) {
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// b := make([]byte, 8)
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// binary.BigEndian.PutUint64(b, val)
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// q.store.Set(key, b)
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// }
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// func (q *Queue) getCount(key []byte) (val uint64) {
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// b := q.store.Get(key)
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// if b != nil {
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// val = binary.BigEndian.Uint64(b)
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// }
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// return val
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// }
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// // makeKey returns the key for a data point
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// func makeKey(val uint64) []byte {
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// b := make([]byte, 8+len(dataKey))
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// copy(b, dataKey)
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// binary.BigEndian.PutUint64(b[len(dataKey):], val)
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// return b
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// }
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