You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
116 lines
2.8 KiB
116 lines
2.8 KiB
/*
|
|
* Copyright 2021 ByteDance Inc.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
package caching
|
|
|
|
import (
|
|
`strings`
|
|
`unsafe`
|
|
|
|
`github.com/bytedance/sonic/internal/rt`
|
|
)
|
|
|
|
type FieldMap struct {
|
|
N uint64
|
|
b unsafe.Pointer
|
|
m map[string]int
|
|
}
|
|
|
|
type FieldEntry struct {
|
|
ID int
|
|
Name string
|
|
Hash uint64
|
|
}
|
|
|
|
const (
|
|
FieldMap_N = int64(unsafe.Offsetof(FieldMap{}.N))
|
|
FieldMap_b = int64(unsafe.Offsetof(FieldMap{}.b))
|
|
FieldEntrySize = int64(unsafe.Sizeof(FieldEntry{}))
|
|
)
|
|
|
|
func newBucket(n int) unsafe.Pointer {
|
|
v := make([]FieldEntry, n)
|
|
return (*rt.GoSlice)(unsafe.Pointer(&v)).Ptr
|
|
}
|
|
|
|
func CreateFieldMap(n int) *FieldMap {
|
|
return &FieldMap {
|
|
N: uint64(n * 2),
|
|
b: newBucket(n * 2), // LoadFactor = 0.5
|
|
m: make(map[string]int, n * 2),
|
|
}
|
|
}
|
|
|
|
func (self *FieldMap) At(p uint64) *FieldEntry {
|
|
off := uintptr(p) * uintptr(FieldEntrySize)
|
|
return (*FieldEntry)(unsafe.Pointer(uintptr(self.b) + off))
|
|
}
|
|
|
|
// Get searches FieldMap by name. JIT generated assembly does NOT call this
|
|
// function, rather it implements its own version directly in assembly. So
|
|
// we must ensure this function stays in sync with the JIT generated one.
|
|
func (self *FieldMap) Get(name string) int {
|
|
h := StrHash(name)
|
|
p := h % self.N
|
|
s := self.At(p)
|
|
|
|
/* find the element;
|
|
* the hash map is never full, so the loop will always terminate */
|
|
for s.Hash != 0 {
|
|
if s.Hash == h && s.Name == name {
|
|
return s.ID
|
|
} else {
|
|
p = (p + 1) % self.N
|
|
s = self.At(p)
|
|
}
|
|
}
|
|
|
|
/* not found */
|
|
return -1
|
|
}
|
|
|
|
func (self *FieldMap) Set(name string, i int) {
|
|
h := StrHash(name)
|
|
p := h % self.N
|
|
s := self.At(p)
|
|
|
|
/* searching for an empty slot;
|
|
* the hash map is never full, so the loop will always terminate */
|
|
for s.Hash != 0 {
|
|
p = (p + 1) % self.N
|
|
s = self.At(p)
|
|
}
|
|
|
|
/* set the value */
|
|
s.ID = i
|
|
s.Hash = h
|
|
s.Name = name
|
|
|
|
/* add the case-insensitive version, prefer the one with smaller field ID */
|
|
key := strings.ToLower(name)
|
|
if v, ok := self.m[key]; !ok || i < v {
|
|
self.m[key] = i
|
|
}
|
|
}
|
|
|
|
func (self *FieldMap) GetCaseInsensitive(name string) int {
|
|
if i, ok := self.m[strings.ToLower(name)]; ok {
|
|
return i
|
|
} else {
|
|
return -1
|
|
}
|
|
}
|