实现基础web服务器

vendor/github.com/bytedance/sonic/internal/encoder/pools.go

@@ -0,0 +1,193 @@
+/*
+ * 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 encoder
+
+import (
+    `bytes`
+    `sync`
+    `unsafe`
+    `errors`
+    `reflect`
+
+    `github.com/bytedance/sonic/internal/caching`
+    `github.com/bytedance/sonic/option`
+    `github.com/bytedance/sonic/internal/rt`
+)
+
+const (
+    _MaxStack  = 4096      // 4k states
+
+    _StackSize = unsafe.Sizeof(_Stack{})
+)
+
+var (
+    bytesPool    = sync.Pool{}
+    stackPool    = sync.Pool{}
+    bufferPool   = sync.Pool{}
+    programCache = caching.CreateProgramCache()
+)
+
+type _State struct {
+    x int
+    f uint64
+    p unsafe.Pointer
+    q unsafe.Pointer
+}
+
+type _Stack struct {
+    sp uint64
+    sb [_MaxStack]_State
+}
+
+type _Encoder func(
+    rb *[]byte,
+    vp unsafe.Pointer,
+    sb *_Stack,
+    fv uint64,
+) error
+
+var _KeepAlive struct {
+    rb *[]byte
+    vp unsafe.Pointer
+    sb *_Stack
+    fv uint64
+    err error
+    frame [_FP_offs]byte
+}
+
+var errCallShadow = errors.New("DON'T CALL THIS!")
+
+// Faker func of _Encoder, used to export its stackmap as _Encoder's
+func _Encoder_Shadow(rb *[]byte, vp unsafe.Pointer, sb *_Stack, fv uint64) (err error) {
+    // align to assembler_amd64.go: _FP_offs
+    var frame [_FP_offs]byte
+
+    // must keep all args and frames noticeable to GC
+    _KeepAlive.rb = rb
+    _KeepAlive.vp = vp
+    _KeepAlive.sb = sb
+    _KeepAlive.fv = fv
+    _KeepAlive.err = err
+    _KeepAlive.frame = frame
+
+    return errCallShadow
+}
+
+func newBytes() []byte {
+    if ret := bytesPool.Get(); ret != nil {
+        return ret.([]byte)
+    } else {
+        return make([]byte, 0, option.DefaultEncoderBufferSize)
+    }
+}
+
+func newStack() *_Stack {
+    if ret := stackPool.Get(); ret == nil {
+        return new(_Stack)
+    } else {
+        return ret.(*_Stack)
+    }
+}
+
+func resetStack(p *_Stack) {
+    memclrNoHeapPointers(unsafe.Pointer(p), _StackSize)
+}
+
+func newBuffer() *bytes.Buffer {
+    if ret := bufferPool.Get(); ret != nil {
+        return ret.(*bytes.Buffer)
+    } else {
+        return bytes.NewBuffer(make([]byte, 0, option.DefaultEncoderBufferSize))
+    }
+}
+
+func freeBytes(p []byte) {
+    p = p[:0]
+    bytesPool.Put(p)
+}
+
+func freeStack(p *_Stack) {
+    p.sp = 0
+    stackPool.Put(p)
+}
+
+func freeBuffer(p *bytes.Buffer) {
+    p.Reset()
+    bufferPool.Put(p)
+}
+
+func makeEncoder(vt *rt.GoType, ex ...interface{}) (interface{}, error) {
+    if pp, err := newCompiler().compile(vt.Pack(), ex[0].(bool)); err != nil {
+        return nil, err
+    } else {
+        as := newAssembler(pp)
+        as.name = vt.String()
+        return as.Load(), nil
+    }
+}
+
+func findOrCompile(vt *rt.GoType, pv bool) (_Encoder, error) {
+    if val := programCache.Get(vt); val != nil {
+        return val.(_Encoder), nil
+    } else if ret, err := programCache.Compute(vt, makeEncoder, pv); err == nil {
+        return ret.(_Encoder), nil
+    } else {
+        return nil, err
+    }
+}
+
+func pretouchType(_vt reflect.Type, opts option.CompileOptions, v uint8) (map[reflect.Type]uint8, error) {
+    /* compile function */
+    compiler := newCompiler().apply(opts)
+    encoder := func(vt *rt.GoType, ex ...interface{}) (interface{}, error) {
+        if pp, err := compiler.compile(_vt, ex[0].(bool)); err != nil {
+            return nil, err
+        } else {
+            as := newAssembler(pp)
+            as.name = vt.String()
+            return as.Load(), nil
+        }
+    }
+
+    /* find or compile */
+    vt := rt.UnpackType(_vt)
+    if val := programCache.Get(vt); val != nil {
+        return nil, nil
+    } else if _, err := programCache.Compute(vt, encoder, v == 1); err == nil {
+        return compiler.rec, nil
+    } else {
+        return nil, err
+    }
+}
+
+func pretouchRec(vtm map[reflect.Type]uint8, opts option.CompileOptions) error {
+    if opts.RecursiveDepth < 0 || len(vtm) == 0 {
+        return nil
+    }
+    next := make(map[reflect.Type]uint8)
+    for vt, v := range vtm {
+        sub, err := pretouchType(vt, opts, v)
+        if err != nil {
+            return err
+        }
+        for svt, v := range sub {
+            next[svt] = v
+        }
+    }
+    opts.RecursiveDepth -= 1
+    return pretouchRec(next, opts)
+}