94 lines
1.7 KiB
Go
94 lines
1.7 KiB
Go
package state
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import (
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"fmt"
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"log"
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)
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type State struct {
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Flags []byte
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CacheSize uint32
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CacheUseSize uint32
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Cache []map[string]string
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CacheMap map[string]string
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ExecPath []string
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}
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func NewState(bitSize uint64) State {
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if bitSize == 0 {
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panic("bitsize cannot be 0")
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}
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n := bitSize % 8
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if n > 0 {
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bitSize += (8 - n)
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}
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return State{
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Flags: make([]byte, bitSize / 8),
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CacheSize: 0,
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CacheUseSize: 0,
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}
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}
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func(st State) WithCacheSize(cacheSize uint32) State {
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st.CacheSize = cacheSize
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return st
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}
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func(st *State) Enter(input string) {
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m := make(map[string]string)
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st.Cache = append(st.Cache, m)
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st.CacheMap = make(map[string]string)
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}
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func(st *State) Add(k string, v string) error {
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sz := st.checkCapacity(v)
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if sz == 0 {
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return fmt.Errorf("Cache capacity exceeded %v of %v", st.CacheUseSize + sz, st.CacheSize)
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}
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log.Printf("add key %s value size %v", k, sz)
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st.Cache[len(st.Cache)-1][k] = v
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st.CacheUseSize += sz
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return nil
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}
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func(st *State) Map(k string) error {
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m, err := st.Get()
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if err != nil {
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return err
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}
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st.CacheMap[k] = m[k]
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return nil
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}
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func(st *State) Get() (map[string]string, error) {
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return st.Cache[len(st.Cache)-1], nil
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}
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func (st *State) Exit() error {
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l := len(st.Cache)
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if l == 0 {
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return fmt.Errorf("exit called beyond top frame")
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}
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l -= 1
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m := st.Cache[l]
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for k, v := range m {
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sz := len(v)
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st.CacheUseSize -= uint32(sz)
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log.Printf("free frame %v key %v value size %v", l, k, sz)
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}
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st.Cache = st.Cache[:l]
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return nil
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}
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func(st *State) checkCapacity(v string) uint32 {
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sz := uint32(len(v))
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if st.CacheSize == 0 {
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return sz
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}
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if st.CacheUseSize + sz > st.CacheSize {
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return 0
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}
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return sz
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}
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