实现基础web服务器

vendor/github.com/bytedance/sonic/internal/loader/funcdata.go

@@ -0,0 +1,124 @@
+/*
+ * 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 loader
+
+import (
+    `reflect`
+    `sync`
+    `unsafe`
+
+    `github.com/bytedance/sonic/internal/rt`
+)
+
+//go:linkname lastmoduledatap runtime.lastmoduledatap
+//goland:noinspection GoUnusedGlobalVariable
+var lastmoduledatap *_ModuleData
+
+//go:linkname moduledataverify1 runtime.moduledataverify1
+func moduledataverify1(_ *_ModuleData)
+
+// PCDATA and FUNCDATA table indexes.
+//
+// See funcdata.h and $GROOT/src/cmd/internal/objabi/funcdata.go.
+const (
+    _FUNCDATA_ArgsPointerMaps = 0
+    _FUNCDATA_LocalsPointerMaps = 1
+)
+
+type funcInfo struct {
+    *_Func
+    datap *_ModuleData
+}
+
+//go:linkname findfunc runtime.findfunc
+func findfunc(pc uintptr) funcInfo
+
+//go:linkname funcdata runtime.funcdata
+func funcdata(f funcInfo, i uint8) unsafe.Pointer
+
+var (
+    modLock sync.Mutex
+    modList []*_ModuleData
+)
+
+var emptyByte byte
+
+func encodeVariant(v int) []byte {
+    var u int
+    var r []byte
+
+    /* split every 7 bits */
+    for v > 127 {
+        u = v & 0x7f
+        v = v >> 7
+        r = append(r, byte(u) | 0x80)
+    }
+
+    /* check for last one */
+    if v == 0 {
+        return r
+    }
+
+    /* add the last one */
+    r = append(r, byte(v))
+    return r
+}
+
+func registerModule(mod *_ModuleData) {
+    modLock.Lock()
+    modList = append(modList, mod)
+    lastmoduledatap.next = mod
+    lastmoduledatap = mod
+    modLock.Unlock()
+}
+
+func stackMap(f interface{}) (args uintptr, locals uintptr) {
+    fv := reflect.ValueOf(f)
+    if fv.Kind() != reflect.Func {
+        panic("f must be reflect.Func kind!")
+    }
+    fi := findfunc(fv.Pointer())
+    return uintptr(funcdata(fi, uint8(_FUNCDATA_ArgsPointerMaps))), uintptr(funcdata(fi, uint8(_FUNCDATA_LocalsPointerMaps)))
+}
+
+var moduleCache = struct{
+    m map[*_ModuleData][]byte
+    l sync.Mutex
+}{
+    m : make(map[*_ModuleData][]byte),
+}
+
+func cacheStackmap(argPtrs []bool, localPtrs []bool, mod *_ModuleData) (argptrs uintptr, localptrs uintptr) {
+    as := rt.StackMapBuilder{}
+    for _, b := range argPtrs {
+        as.AddField(b)
+    }
+    ab, _ := as.Build().MarshalBinary()
+    ls := rt.StackMapBuilder{}
+    for _, b := range localPtrs {
+        ls.AddField(b)
+    }
+    lb, _ := ls.Build().MarshalBinary()
+    cache := make([]byte, len(ab) + len(lb))
+    copy(cache, ab)
+    copy(cache[len(ab):], lb)
+    moduleCache.l.Lock()
+    moduleCache.m[mod] = cache
+    moduleCache.l.Unlock()
+    return uintptr(rt.IndexByte(cache, 0)), uintptr(rt.IndexByte(cache, len(ab)))
+
+}