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-rw-r--r--src/go/internal/gcimporter/iimport.go817
1 files changed, 817 insertions, 0 deletions
diff --git a/src/go/internal/gcimporter/iimport.go b/src/go/internal/gcimporter/iimport.go
new file mode 100644
index 0000000..9e3c945
--- /dev/null
+++ b/src/go/internal/gcimporter/iimport.go
@@ -0,0 +1,817 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Indexed package import.
+// See cmd/compile/internal/gc/iexport.go for the export data format.
+
+package gcimporter
+
+import (
+ "bufio"
+ "bytes"
+ "encoding/binary"
+ "fmt"
+ "go/constant"
+ "go/token"
+ "go/types"
+ "internal/saferio"
+ "io"
+ "math"
+ "math/big"
+ "sort"
+ "strings"
+)
+
+type intReader struct {
+ *bufio.Reader
+ path string
+}
+
+func (r *intReader) int64() int64 {
+ i, err := binary.ReadVarint(r.Reader)
+ if err != nil {
+ errorf("import %q: read varint error: %v", r.path, err)
+ }
+ return i
+}
+
+func (r *intReader) uint64() uint64 {
+ i, err := binary.ReadUvarint(r.Reader)
+ if err != nil {
+ errorf("import %q: read varint error: %v", r.path, err)
+ }
+ return i
+}
+
+// Keep this in sync with constants in iexport.go.
+const (
+ iexportVersionGo1_11 = 0
+ iexportVersionPosCol = 1
+ iexportVersionGenerics = 2
+ iexportVersionGo1_18 = 2
+
+ iexportVersionCurrent = 2
+)
+
+type ident struct {
+ pkg *types.Package
+ name string
+}
+
+const predeclReserved = 32
+
+type itag uint64
+
+const (
+ // Types
+ definedType itag = iota
+ pointerType
+ sliceType
+ arrayType
+ chanType
+ mapType
+ signatureType
+ structType
+ interfaceType
+ typeParamType
+ instanceType
+ unionType
+)
+
+// iImportData imports a package from the serialized package data
+// and returns the number of bytes consumed and a reference to the package.
+// If the export data version is not recognized or the format is otherwise
+// compromised, an error is returned.
+func iImportData(fset *token.FileSet, imports map[string]*types.Package, dataReader *bufio.Reader, path string) (pkg *types.Package, err error) {
+ const currentVersion = iexportVersionCurrent
+ version := int64(-1)
+ defer func() {
+ if e := recover(); e != nil {
+ if version > currentVersion {
+ err = fmt.Errorf("cannot import %q (%v), export data is newer version - update tool", path, e)
+ } else {
+ err = fmt.Errorf("cannot import %q (%v), possibly version skew - reinstall package", path, e)
+ }
+ }
+ }()
+
+ r := &intReader{dataReader, path}
+
+ version = int64(r.uint64())
+ switch version {
+ case iexportVersionGo1_18, iexportVersionPosCol, iexportVersionGo1_11:
+ default:
+ errorf("unknown iexport format version %d", version)
+ }
+
+ sLen := r.uint64()
+ dLen := r.uint64()
+
+ if sLen > math.MaxUint64-dLen {
+ errorf("lengths out of range (%d, %d)", sLen, dLen)
+ }
+
+ data, err := saferio.ReadData(r, sLen+dLen)
+ if err != nil {
+ errorf("cannot read %d bytes of stringData and declData: %s", sLen+dLen, err)
+ }
+ stringData := data[:sLen]
+ declData := data[sLen:]
+
+ p := iimporter{
+ exportVersion: version,
+ ipath: path,
+ version: int(version),
+
+ stringData: stringData,
+ stringCache: make(map[uint64]string),
+ pkgCache: make(map[uint64]*types.Package),
+
+ declData: declData,
+ pkgIndex: make(map[*types.Package]map[string]uint64),
+ typCache: make(map[uint64]types.Type),
+ // Separate map for typeparams, keyed by their package and unique
+ // name (name with subscript).
+ tparamIndex: make(map[ident]*types.TypeParam),
+
+ fake: fakeFileSet{
+ fset: fset,
+ files: make(map[string]*fileInfo),
+ },
+ }
+ defer p.fake.setLines() // set lines for files in fset
+
+ for i, pt := range predeclared {
+ p.typCache[uint64(i)] = pt
+ }
+
+ pkgList := make([]*types.Package, r.uint64())
+ for i := range pkgList {
+ pkgPathOff := r.uint64()
+ pkgPath := p.stringAt(pkgPathOff)
+ pkgName := p.stringAt(r.uint64())
+ _ = r.uint64() // package height; unused by go/types
+
+ if pkgPath == "" {
+ pkgPath = path
+ }
+ pkg := imports[pkgPath]
+ if pkg == nil {
+ pkg = types.NewPackage(pkgPath, pkgName)
+ imports[pkgPath] = pkg
+ } else if pkg.Name() != pkgName {
+ errorf("conflicting names %s and %s for package %q", pkg.Name(), pkgName, path)
+ }
+
+ p.pkgCache[pkgPathOff] = pkg
+
+ nameIndex := make(map[string]uint64)
+ for nSyms := r.uint64(); nSyms > 0; nSyms-- {
+ name := p.stringAt(r.uint64())
+ nameIndex[name] = r.uint64()
+ }
+
+ p.pkgIndex[pkg] = nameIndex
+ pkgList[i] = pkg
+ }
+
+ localpkg := pkgList[0]
+
+ names := make([]string, 0, len(p.pkgIndex[localpkg]))
+ for name := range p.pkgIndex[localpkg] {
+ names = append(names, name)
+ }
+ sort.Strings(names)
+ for _, name := range names {
+ p.doDecl(localpkg, name)
+ }
+
+ // SetConstraint can't be called if the constraint type is not yet complete.
+ // When type params are created in the 'P' case of (*importReader).obj(),
+ // the associated constraint type may not be complete due to recursion.
+ // Therefore, we defer calling SetConstraint there, and call it here instead
+ // after all types are complete.
+ for _, d := range p.later {
+ d.t.SetConstraint(d.constraint)
+ }
+
+ for _, typ := range p.interfaceList {
+ typ.Complete()
+ }
+
+ // record all referenced packages as imports
+ list := append(([]*types.Package)(nil), pkgList[1:]...)
+ sort.Sort(byPath(list))
+ localpkg.SetImports(list)
+
+ // package was imported completely and without errors
+ localpkg.MarkComplete()
+ return localpkg, nil
+}
+
+type setConstraintArgs struct {
+ t *types.TypeParam
+ constraint types.Type
+}
+
+type iimporter struct {
+ exportVersion int64
+ ipath string
+ version int
+
+ stringData []byte
+ stringCache map[uint64]string
+ pkgCache map[uint64]*types.Package
+
+ declData []byte
+ pkgIndex map[*types.Package]map[string]uint64
+ typCache map[uint64]types.Type
+ tparamIndex map[ident]*types.TypeParam
+
+ fake fakeFileSet
+ interfaceList []*types.Interface
+
+ // Arguments for calls to SetConstraint that are deferred due to recursive types
+ later []setConstraintArgs
+}
+
+func (p *iimporter) doDecl(pkg *types.Package, name string) {
+ // See if we've already imported this declaration.
+ if obj := pkg.Scope().Lookup(name); obj != nil {
+ return
+ }
+
+ off, ok := p.pkgIndex[pkg][name]
+ if !ok {
+ errorf("%v.%v not in index", pkg, name)
+ }
+
+ r := &importReader{p: p, currPkg: pkg}
+ r.declReader.Reset(p.declData[off:])
+
+ r.obj(name)
+}
+
+func (p *iimporter) stringAt(off uint64) string {
+ if s, ok := p.stringCache[off]; ok {
+ return s
+ }
+
+ slen, n := binary.Uvarint(p.stringData[off:])
+ if n <= 0 {
+ errorf("varint failed")
+ }
+ spos := off + uint64(n)
+ s := string(p.stringData[spos : spos+slen])
+ p.stringCache[off] = s
+ return s
+}
+
+func (p *iimporter) pkgAt(off uint64) *types.Package {
+ if pkg, ok := p.pkgCache[off]; ok {
+ return pkg
+ }
+ path := p.stringAt(off)
+ errorf("missing package %q in %q", path, p.ipath)
+ return nil
+}
+
+func (p *iimporter) typAt(off uint64, base *types.Named) types.Type {
+ if t, ok := p.typCache[off]; ok && canReuse(base, t) {
+ return t
+ }
+
+ if off < predeclReserved {
+ errorf("predeclared type missing from cache: %v", off)
+ }
+
+ r := &importReader{p: p}
+ r.declReader.Reset(p.declData[off-predeclReserved:])
+ t := r.doType(base)
+
+ if canReuse(base, t) {
+ p.typCache[off] = t
+ }
+ return t
+}
+
+// canReuse reports whether the type rhs on the RHS of the declaration for def
+// may be re-used.
+//
+// Specifically, if def is non-nil and rhs is an interface type with methods, it
+// may not be re-used because we have a convention of setting the receiver type
+// for interface methods to def.
+func canReuse(def *types.Named, rhs types.Type) bool {
+ if def == nil {
+ return true
+ }
+ iface, _ := rhs.(*types.Interface)
+ if iface == nil {
+ return true
+ }
+ // Don't use iface.Empty() here as iface may not be complete.
+ return iface.NumEmbeddeds() == 0 && iface.NumExplicitMethods() == 0
+}
+
+type importReader struct {
+ p *iimporter
+ declReader bytes.Reader
+ currPkg *types.Package
+ prevFile string
+ prevLine int64
+ prevColumn int64
+}
+
+func (r *importReader) obj(name string) {
+ tag := r.byte()
+ pos := r.pos()
+
+ switch tag {
+ case 'A':
+ typ := r.typ()
+
+ r.declare(types.NewTypeName(pos, r.currPkg, name, typ))
+
+ case 'C':
+ typ, val := r.value()
+
+ r.declare(types.NewConst(pos, r.currPkg, name, typ, val))
+
+ case 'F', 'G':
+ var tparams []*types.TypeParam
+ if tag == 'G' {
+ tparams = r.tparamList()
+ }
+ sig := r.signature(nil, nil, tparams)
+ r.declare(types.NewFunc(pos, r.currPkg, name, sig))
+
+ case 'T', 'U':
+ // Types can be recursive. We need to setup a stub
+ // declaration before recurring.
+ obj := types.NewTypeName(pos, r.currPkg, name, nil)
+ named := types.NewNamed(obj, nil, nil)
+ // Declare obj before calling r.tparamList, so the new type name is recognized
+ // if used in the constraint of one of its own typeparams (see #48280).
+ r.declare(obj)
+ if tag == 'U' {
+ tparams := r.tparamList()
+ named.SetTypeParams(tparams)
+ }
+
+ underlying := r.p.typAt(r.uint64(), named).Underlying()
+ named.SetUnderlying(underlying)
+
+ if !isInterface(underlying) {
+ for n := r.uint64(); n > 0; n-- {
+ mpos := r.pos()
+ mname := r.ident()
+ recv := r.param()
+
+ // If the receiver has any targs, set those as the
+ // rparams of the method (since those are the
+ // typeparams being used in the method sig/body).
+ targs := baseType(recv.Type()).TypeArgs()
+ var rparams []*types.TypeParam
+ if targs.Len() > 0 {
+ rparams = make([]*types.TypeParam, targs.Len())
+ for i := range rparams {
+ rparams[i], _ = targs.At(i).(*types.TypeParam)
+ }
+ }
+ msig := r.signature(recv, rparams, nil)
+
+ named.AddMethod(types.NewFunc(mpos, r.currPkg, mname, msig))
+ }
+ }
+
+ case 'P':
+ // We need to "declare" a typeparam in order to have a name that
+ // can be referenced recursively (if needed) in the type param's
+ // bound.
+ if r.p.exportVersion < iexportVersionGenerics {
+ errorf("unexpected type param type")
+ }
+ // Remove the "path" from the type param name that makes it unique,
+ // and revert any unique name used for blank typeparams.
+ name0 := tparamName(name)
+ tn := types.NewTypeName(pos, r.currPkg, name0, nil)
+ t := types.NewTypeParam(tn, nil)
+ // To handle recursive references to the typeparam within its
+ // bound, save the partial type in tparamIndex before reading the bounds.
+ id := ident{r.currPkg, name}
+ r.p.tparamIndex[id] = t
+
+ var implicit bool
+ if r.p.exportVersion >= iexportVersionGo1_18 {
+ implicit = r.bool()
+ }
+ constraint := r.typ()
+ if implicit {
+ iface, _ := constraint.(*types.Interface)
+ if iface == nil {
+ errorf("non-interface constraint marked implicit")
+ }
+ iface.MarkImplicit()
+ }
+ // The constraint type may not be complete, if we
+ // are in the middle of a type recursion involving type
+ // constraints. So, we defer SetConstraint until we have
+ // completely set up all types in ImportData.
+ r.p.later = append(r.p.later, setConstraintArgs{t: t, constraint: constraint})
+
+ case 'V':
+ typ := r.typ()
+
+ r.declare(types.NewVar(pos, r.currPkg, name, typ))
+
+ default:
+ errorf("unexpected tag: %v", tag)
+ }
+}
+
+func (r *importReader) declare(obj types.Object) {
+ obj.Pkg().Scope().Insert(obj)
+}
+
+func (r *importReader) value() (typ types.Type, val constant.Value) {
+ typ = r.typ()
+ if r.p.exportVersion >= iexportVersionGo1_18 {
+ // TODO: add support for using the kind
+ _ = constant.Kind(r.int64())
+ }
+
+ switch b := typ.Underlying().(*types.Basic); b.Info() & types.IsConstType {
+ case types.IsBoolean:
+ val = constant.MakeBool(r.bool())
+
+ case types.IsString:
+ val = constant.MakeString(r.string())
+
+ case types.IsInteger:
+ var x big.Int
+ r.mpint(&x, b)
+ val = constant.Make(&x)
+
+ case types.IsFloat:
+ val = r.mpfloat(b)
+
+ case types.IsComplex:
+ re := r.mpfloat(b)
+ im := r.mpfloat(b)
+ val = constant.BinaryOp(re, token.ADD, constant.MakeImag(im))
+
+ default:
+ errorf("unexpected type %v", typ) // panics
+ panic("unreachable")
+ }
+
+ return
+}
+
+func intSize(b *types.Basic) (signed bool, maxBytes uint) {
+ if (b.Info() & types.IsUntyped) != 0 {
+ return true, 64
+ }
+
+ switch b.Kind() {
+ case types.Float32, types.Complex64:
+ return true, 3
+ case types.Float64, types.Complex128:
+ return true, 7
+ }
+
+ signed = (b.Info() & types.IsUnsigned) == 0
+ switch b.Kind() {
+ case types.Int8, types.Uint8:
+ maxBytes = 1
+ case types.Int16, types.Uint16:
+ maxBytes = 2
+ case types.Int32, types.Uint32:
+ maxBytes = 4
+ default:
+ maxBytes = 8
+ }
+
+ return
+}
+
+func (r *importReader) mpint(x *big.Int, typ *types.Basic) {
+ signed, maxBytes := intSize(typ)
+
+ maxSmall := 256 - maxBytes
+ if signed {
+ maxSmall = 256 - 2*maxBytes
+ }
+ if maxBytes == 1 {
+ maxSmall = 256
+ }
+
+ n, _ := r.declReader.ReadByte()
+ if uint(n) < maxSmall {
+ v := int64(n)
+ if signed {
+ v >>= 1
+ if n&1 != 0 {
+ v = ^v
+ }
+ }
+ x.SetInt64(v)
+ return
+ }
+
+ v := -n
+ if signed {
+ v = -(n &^ 1) >> 1
+ }
+ if v < 1 || uint(v) > maxBytes {
+ errorf("weird decoding: %v, %v => %v", n, signed, v)
+ }
+ b := make([]byte, v)
+ io.ReadFull(&r.declReader, b)
+ x.SetBytes(b)
+ if signed && n&1 != 0 {
+ x.Neg(x)
+ }
+}
+
+func (r *importReader) mpfloat(typ *types.Basic) constant.Value {
+ var mant big.Int
+ r.mpint(&mant, typ)
+ var f big.Float
+ f.SetInt(&mant)
+ if f.Sign() != 0 {
+ f.SetMantExp(&f, int(r.int64()))
+ }
+ return constant.Make(&f)
+}
+
+func (r *importReader) ident() string {
+ return r.string()
+}
+
+func (r *importReader) qualifiedIdent() (*types.Package, string) {
+ name := r.string()
+ pkg := r.pkg()
+ return pkg, name
+}
+
+func (r *importReader) pos() token.Pos {
+ if r.p.version >= 1 {
+ r.posv1()
+ } else {
+ r.posv0()
+ }
+
+ if r.prevFile == "" && r.prevLine == 0 && r.prevColumn == 0 {
+ return token.NoPos
+ }
+ return r.p.fake.pos(r.prevFile, int(r.prevLine), int(r.prevColumn))
+}
+
+func (r *importReader) posv0() {
+ delta := r.int64()
+ if delta != deltaNewFile {
+ r.prevLine += delta
+ } else if l := r.int64(); l == -1 {
+ r.prevLine += deltaNewFile
+ } else {
+ r.prevFile = r.string()
+ r.prevLine = l
+ }
+}
+
+func (r *importReader) posv1() {
+ delta := r.int64()
+ r.prevColumn += delta >> 1
+ if delta&1 != 0 {
+ delta = r.int64()
+ r.prevLine += delta >> 1
+ if delta&1 != 0 {
+ r.prevFile = r.string()
+ }
+ }
+}
+
+func (r *importReader) typ() types.Type {
+ return r.p.typAt(r.uint64(), nil)
+}
+
+func isInterface(t types.Type) bool {
+ _, ok := t.(*types.Interface)
+ return ok
+}
+
+func (r *importReader) pkg() *types.Package { return r.p.pkgAt(r.uint64()) }
+func (r *importReader) string() string { return r.p.stringAt(r.uint64()) }
+
+func (r *importReader) doType(base *types.Named) types.Type {
+ switch k := r.kind(); k {
+ default:
+ errorf("unexpected kind tag in %q: %v", r.p.ipath, k)
+ return nil
+
+ case definedType:
+ pkg, name := r.qualifiedIdent()
+ r.p.doDecl(pkg, name)
+ return pkg.Scope().Lookup(name).(*types.TypeName).Type()
+ case pointerType:
+ return types.NewPointer(r.typ())
+ case sliceType:
+ return types.NewSlice(r.typ())
+ case arrayType:
+ n := r.uint64()
+ return types.NewArray(r.typ(), int64(n))
+ case chanType:
+ dir := chanDir(int(r.uint64()))
+ return types.NewChan(dir, r.typ())
+ case mapType:
+ return types.NewMap(r.typ(), r.typ())
+ case signatureType:
+ r.currPkg = r.pkg()
+ return r.signature(nil, nil, nil)
+
+ case structType:
+ r.currPkg = r.pkg()
+
+ fields := make([]*types.Var, r.uint64())
+ tags := make([]string, len(fields))
+ for i := range fields {
+ fpos := r.pos()
+ fname := r.ident()
+ ftyp := r.typ()
+ emb := r.bool()
+ tag := r.string()
+
+ fields[i] = types.NewField(fpos, r.currPkg, fname, ftyp, emb)
+ tags[i] = tag
+ }
+ return types.NewStruct(fields, tags)
+
+ case interfaceType:
+ r.currPkg = r.pkg()
+
+ embeddeds := make([]types.Type, r.uint64())
+ for i := range embeddeds {
+ _ = r.pos()
+ embeddeds[i] = r.typ()
+ }
+
+ methods := make([]*types.Func, r.uint64())
+ for i := range methods {
+ mpos := r.pos()
+ mname := r.ident()
+
+ // TODO(mdempsky): Matches bimport.go, but I
+ // don't agree with this.
+ var recv *types.Var
+ if base != nil {
+ recv = types.NewVar(token.NoPos, r.currPkg, "", base)
+ }
+
+ msig := r.signature(recv, nil, nil)
+ methods[i] = types.NewFunc(mpos, r.currPkg, mname, msig)
+ }
+
+ typ := types.NewInterfaceType(methods, embeddeds)
+ r.p.interfaceList = append(r.p.interfaceList, typ)
+ return typ
+
+ case typeParamType:
+ if r.p.exportVersion < iexportVersionGenerics {
+ errorf("unexpected type param type")
+ }
+ pkg, name := r.qualifiedIdent()
+ id := ident{pkg, name}
+ if t, ok := r.p.tparamIndex[id]; ok {
+ // We're already in the process of importing this typeparam.
+ return t
+ }
+ // Otherwise, import the definition of the typeparam now.
+ r.p.doDecl(pkg, name)
+ return r.p.tparamIndex[id]
+
+ case instanceType:
+ if r.p.exportVersion < iexportVersionGenerics {
+ errorf("unexpected instantiation type")
+ }
+ // pos does not matter for instances: they are positioned on the original
+ // type.
+ _ = r.pos()
+ len := r.uint64()
+ targs := make([]types.Type, len)
+ for i := range targs {
+ targs[i] = r.typ()
+ }
+ baseType := r.typ()
+ // The imported instantiated type doesn't include any methods, so
+ // we must always use the methods of the base (orig) type.
+ // TODO provide a non-nil *Context
+ t, _ := types.Instantiate(nil, baseType, targs, false)
+ return t
+
+ case unionType:
+ if r.p.exportVersion < iexportVersionGenerics {
+ errorf("unexpected instantiation type")
+ }
+ terms := make([]*types.Term, r.uint64())
+ for i := range terms {
+ terms[i] = types.NewTerm(r.bool(), r.typ())
+ }
+ return types.NewUnion(terms)
+ }
+}
+
+func (r *importReader) kind() itag {
+ return itag(r.uint64())
+}
+
+func (r *importReader) signature(recv *types.Var, rparams, tparams []*types.TypeParam) *types.Signature {
+ params := r.paramList()
+ results := r.paramList()
+ variadic := params.Len() > 0 && r.bool()
+ return types.NewSignatureType(recv, rparams, tparams, params, results, variadic)
+}
+
+func (r *importReader) tparamList() []*types.TypeParam {
+ n := r.uint64()
+ if n == 0 {
+ return nil
+ }
+ xs := make([]*types.TypeParam, n)
+ for i := range xs {
+ xs[i], _ = r.typ().(*types.TypeParam)
+ }
+ return xs
+}
+
+func (r *importReader) paramList() *types.Tuple {
+ xs := make([]*types.Var, r.uint64())
+ for i := range xs {
+ xs[i] = r.param()
+ }
+ return types.NewTuple(xs...)
+}
+
+func (r *importReader) param() *types.Var {
+ pos := r.pos()
+ name := r.ident()
+ typ := r.typ()
+ return types.NewParam(pos, r.currPkg, name, typ)
+}
+
+func (r *importReader) bool() bool {
+ return r.uint64() != 0
+}
+
+func (r *importReader) int64() int64 {
+ n, err := binary.ReadVarint(&r.declReader)
+ if err != nil {
+ errorf("readVarint: %v", err)
+ }
+ return n
+}
+
+func (r *importReader) uint64() uint64 {
+ n, err := binary.ReadUvarint(&r.declReader)
+ if err != nil {
+ errorf("readUvarint: %v", err)
+ }
+ return n
+}
+
+func (r *importReader) byte() byte {
+ x, err := r.declReader.ReadByte()
+ if err != nil {
+ errorf("declReader.ReadByte: %v", err)
+ }
+ return x
+}
+
+func baseType(typ types.Type) *types.Named {
+ // pointer receivers are never types.Named types
+ if p, _ := typ.(*types.Pointer); p != nil {
+ typ = p.Elem()
+ }
+ // receiver base types are always (possibly generic) types.Named types
+ n, _ := typ.(*types.Named)
+ return n
+}
+
+const blankMarker = "$"
+
+// tparamName returns the real name of a type parameter, after stripping its
+// qualifying prefix and reverting blank-name encoding. See tparamExportName
+// for details.
+func tparamName(exportName string) string {
+ // Remove the "path" from the type param name that makes it unique.
+ ix := strings.LastIndex(exportName, ".")
+ if ix < 0 {
+ errorf("malformed type parameter export name %s: missing prefix", exportName)
+ }
+ name := exportName[ix+1:]
+ if strings.HasPrefix(name, blankMarker) {
+ return "_"
+ }
+ return name
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-17 04:58:04 +0000