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-rw-r--r--internal/gcimporter/bimport.go1053
1 files changed, 1053 insertions, 0 deletions
diff --git a/internal/gcimporter/bimport.go b/internal/gcimporter/bimport.go
new file mode 100644
index 000000000..b85de0147
--- /dev/null
+++ b/internal/gcimporter/bimport.go
@@ -0,0 +1,1053 @@
+// Copyright 2015 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.
+
+// This file is a copy of $GOROOT/src/go/internal/gcimporter/bimport.go.
+
+package gcimporter
+
+import (
+ "encoding/binary"
+ "fmt"
+ "go/constant"
+ "go/token"
+ "go/types"
+ "sort"
+ "strconv"
+ "strings"
+ "sync"
+ "unicode"
+ "unicode/utf8"
+)
+
+type importer struct {
+ imports map[string]*types.Package
+ data []byte
+ importpath string
+ buf []byte // for reading strings
+ version int // export format version
+
+ // object lists
+ strList []string // in order of appearance
+ pathList []string // in order of appearance
+ pkgList []*types.Package // in order of appearance
+ typList []types.Type // in order of appearance
+ interfaceList []*types.Interface // for delayed completion only
+ trackAllTypes bool
+
+ // position encoding
+ posInfoFormat bool
+ prevFile string
+ prevLine int
+ fake fakeFileSet
+
+ // debugging support
+ debugFormat bool
+ read int // bytes read
+}
+
+// BImportData 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 BImportData(fset *token.FileSet, imports map[string]*types.Package, data []byte, path string) (_ int, pkg *types.Package, err error) {
+ // catch panics and return them as errors
+ const currentVersion = 6
+ version := -1 // unknown version
+ defer func() {
+ if e := recover(); e != nil {
+ // Return a (possibly nil or incomplete) package unchanged (see #16088).
+ 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)
+ }
+ }
+ }()
+
+ p := importer{
+ imports: imports,
+ data: data,
+ importpath: path,
+ version: version,
+ strList: []string{""}, // empty string is mapped to 0
+ pathList: []string{""}, // empty string is mapped to 0
+ fake: fakeFileSet{
+ fset: fset,
+ files: make(map[string]*fileInfo),
+ },
+ }
+ defer p.fake.setLines() // set lines for files in fset
+
+ // read version info
+ var versionstr string
+ if b := p.rawByte(); b == 'c' || b == 'd' {
+ // Go1.7 encoding; first byte encodes low-level
+ // encoding format (compact vs debug).
+ // For backward-compatibility only (avoid problems with
+ // old installed packages). Newly compiled packages use
+ // the extensible format string.
+ // TODO(gri) Remove this support eventually; after Go1.8.
+ if b == 'd' {
+ p.debugFormat = true
+ }
+ p.trackAllTypes = p.rawByte() == 'a'
+ p.posInfoFormat = p.int() != 0
+ versionstr = p.string()
+ if versionstr == "v1" {
+ version = 0
+ }
+ } else {
+ // Go1.8 extensible encoding
+ // read version string and extract version number (ignore anything after the version number)
+ versionstr = p.rawStringln(b)
+ if s := strings.SplitN(versionstr, " ", 3); len(s) >= 2 && s[0] == "version" {
+ if v, err := strconv.Atoi(s[1]); err == nil && v > 0 {
+ version = v
+ }
+ }
+ }
+ p.version = version
+
+ // read version specific flags - extend as necessary
+ switch p.version {
+ // case currentVersion:
+ // ...
+ // fallthrough
+ case currentVersion, 5, 4, 3, 2, 1:
+ p.debugFormat = p.rawStringln(p.rawByte()) == "debug"
+ p.trackAllTypes = p.int() != 0
+ p.posInfoFormat = p.int() != 0
+ case 0:
+ // Go1.7 encoding format - nothing to do here
+ default:
+ errorf("unknown bexport format version %d (%q)", p.version, versionstr)
+ }
+
+ // --- generic export data ---
+
+ // populate typList with predeclared "known" types
+ p.typList = append(p.typList, predeclared()...)
+
+ // read package data
+ pkg = p.pkg()
+
+ // read objects of phase 1 only (see cmd/compile/internal/gc/bexport.go)
+ objcount := 0
+ for {
+ tag := p.tagOrIndex()
+ if tag == endTag {
+ break
+ }
+ p.obj(tag)
+ objcount++
+ }
+
+ // self-verification
+ if count := p.int(); count != objcount {
+ errorf("got %d objects; want %d", objcount, count)
+ }
+
+ // ignore compiler-specific import data
+
+ // complete interfaces
+ // TODO(gri) re-investigate if we still need to do this in a delayed fashion
+ for _, typ := range p.interfaceList {
+ typ.Complete()
+ }
+
+ // record all referenced packages as imports
+ list := append(([]*types.Package)(nil), p.pkgList[1:]...)
+ sort.Sort(byPath(list))
+ pkg.SetImports(list)
+
+ // package was imported completely and without errors
+ pkg.MarkComplete()
+
+ return p.read, pkg, nil
+}
+
+func errorf(format string, args ...interface{}) {
+ panic(fmt.Sprintf(format, args...))
+}
+
+func (p *importer) pkg() *types.Package {
+ // if the package was seen before, i is its index (>= 0)
+ i := p.tagOrIndex()
+ if i >= 0 {
+ return p.pkgList[i]
+ }
+
+ // otherwise, i is the package tag (< 0)
+ if i != packageTag {
+ errorf("unexpected package tag %d version %d", i, p.version)
+ }
+
+ // read package data
+ name := p.string()
+ var path string
+ if p.version >= 5 {
+ path = p.path()
+ } else {
+ path = p.string()
+ }
+ if p.version >= 6 {
+ p.int() // package height; unused by go/types
+ }
+
+ // we should never see an empty package name
+ if name == "" {
+ errorf("empty package name in import")
+ }
+
+ // an empty path denotes the package we are currently importing;
+ // it must be the first package we see
+ if (path == "") != (len(p.pkgList) == 0) {
+ errorf("package path %q for pkg index %d", path, len(p.pkgList))
+ }
+
+ // if the package was imported before, use that one; otherwise create a new one
+ if path == "" {
+ path = p.importpath
+ }
+ pkg := p.imports[path]
+ if pkg == nil {
+ pkg = types.NewPackage(path, name)
+ p.imports[path] = pkg
+ } else if pkg.Name() != name {
+ errorf("conflicting names %s and %s for package %q", pkg.Name(), name, path)
+ }
+ p.pkgList = append(p.pkgList, pkg)
+
+ return pkg
+}
+
+// objTag returns the tag value for each object kind.
+func objTag(obj types.Object) int {
+ switch obj.(type) {
+ case *types.Const:
+ return constTag
+ case *types.TypeName:
+ return typeTag
+ case *types.Var:
+ return varTag
+ case *types.Func:
+ return funcTag
+ default:
+ errorf("unexpected object: %v (%T)", obj, obj) // panics
+ panic("unreachable")
+ }
+}
+
+func sameObj(a, b types.Object) bool {
+ // Because unnamed types are not canonicalized, we cannot simply compare types for
+ // (pointer) identity.
+ // Ideally we'd check equality of constant values as well, but this is good enough.
+ return objTag(a) == objTag(b) && types.Identical(a.Type(), b.Type())
+}
+
+func (p *importer) declare(obj types.Object) {
+ pkg := obj.Pkg()
+ if alt := pkg.Scope().Insert(obj); alt != nil {
+ // This can only trigger if we import a (non-type) object a second time.
+ // Excluding type aliases, this cannot happen because 1) we only import a package
+ // once; and b) we ignore compiler-specific export data which may contain
+ // functions whose inlined function bodies refer to other functions that
+ // were already imported.
+ // However, type aliases require reexporting the original type, so we need
+ // to allow it (see also the comment in cmd/compile/internal/gc/bimport.go,
+ // method importer.obj, switch case importing functions).
+ // TODO(gri) review/update this comment once the gc compiler handles type aliases.
+ if !sameObj(obj, alt) {
+ errorf("inconsistent import:\n\t%v\npreviously imported as:\n\t%v\n", obj, alt)
+ }
+ }
+}
+
+func (p *importer) obj(tag int) {
+ switch tag {
+ case constTag:
+ pos := p.pos()
+ pkg, name := p.qualifiedName()
+ typ := p.typ(nil, nil)
+ val := p.value()
+ p.declare(types.NewConst(pos, pkg, name, typ, val))
+
+ case aliasTag:
+ // TODO(gri) verify type alias hookup is correct
+ pos := p.pos()
+ pkg, name := p.qualifiedName()
+ typ := p.typ(nil, nil)
+ p.declare(types.NewTypeName(pos, pkg, name, typ))
+
+ case typeTag:
+ p.typ(nil, nil)
+
+ case varTag:
+ pos := p.pos()
+ pkg, name := p.qualifiedName()
+ typ := p.typ(nil, nil)
+ p.declare(types.NewVar(pos, pkg, name, typ))
+
+ case funcTag:
+ pos := p.pos()
+ pkg, name := p.qualifiedName()
+ params, isddd := p.paramList()
+ result, _ := p.paramList()
+ sig := types.NewSignature(nil, params, result, isddd)
+ p.declare(types.NewFunc(pos, pkg, name, sig))
+
+ default:
+ errorf("unexpected object tag %d", tag)
+ }
+}
+
+const deltaNewFile = -64 // see cmd/compile/internal/gc/bexport.go
+
+func (p *importer) pos() token.Pos {
+ if !p.posInfoFormat {
+ return token.NoPos
+ }
+
+ file := p.prevFile
+ line := p.prevLine
+ delta := p.int()
+ line += delta
+ if p.version >= 5 {
+ if delta == deltaNewFile {
+ if n := p.int(); n >= 0 {
+ // file changed
+ file = p.path()
+ line = n
+ }
+ }
+ } else {
+ if delta == 0 {
+ if n := p.int(); n >= 0 {
+ // file changed
+ file = p.prevFile[:n] + p.string()
+ line = p.int()
+ }
+ }
+ }
+ p.prevFile = file
+ p.prevLine = line
+
+ return p.fake.pos(file, line, 0)
+}
+
+// Synthesize a token.Pos
+type fakeFileSet struct {
+ fset *token.FileSet
+ files map[string]*fileInfo
+}
+
+type fileInfo struct {
+ file *token.File
+ lastline int
+}
+
+const maxlines = 64 * 1024
+
+func (s *fakeFileSet) pos(file string, line, column int) token.Pos {
+ // TODO(mdempsky): Make use of column.
+
+ // Since we don't know the set of needed file positions, we reserve maxlines
+ // positions per file. We delay calling token.File.SetLines until all
+ // positions have been calculated (by way of fakeFileSet.setLines), so that
+ // we can avoid setting unnecessary lines. See also golang/go#46586.
+ f := s.files[file]
+ if f == nil {
+ f = &fileInfo{file: s.fset.AddFile(file, -1, maxlines)}
+ s.files[file] = f
+ }
+ if line > maxlines {
+ line = 1
+ }
+ if line > f.lastline {
+ f.lastline = line
+ }
+
+ // Return a fake position assuming that f.file consists only of newlines.
+ return token.Pos(f.file.Base() + line - 1)
+}
+
+func (s *fakeFileSet) setLines() {
+ fakeLinesOnce.Do(func() {
+ fakeLines = make([]int, maxlines)
+ for i := range fakeLines {
+ fakeLines[i] = i
+ }
+ })
+ for _, f := range s.files {
+ f.file.SetLines(fakeLines[:f.lastline])
+ }
+}
+
+var (
+ fakeLines []int
+ fakeLinesOnce sync.Once
+)
+
+func (p *importer) qualifiedName() (pkg *types.Package, name string) {
+ name = p.string()
+ pkg = p.pkg()
+ return
+}
+
+func (p *importer) record(t types.Type) {
+ p.typList = append(p.typList, t)
+}
+
+// A dddSlice is a types.Type representing ...T parameters.
+// It only appears for parameter types and does not escape
+// the importer.
+type dddSlice struct {
+ elem types.Type
+}
+
+func (t *dddSlice) Underlying() types.Type { return t }
+func (t *dddSlice) String() string { return "..." + t.elem.String() }
+
+// parent is the package which declared the type; parent == nil means
+// the package currently imported. The parent package is needed for
+// exported struct fields and interface methods which don't contain
+// explicit package information in the export data.
+//
+// A non-nil tname is used as the "owner" of the result type; i.e.,
+// the result type is the underlying type of tname. tname is used
+// to give interface methods a named receiver type where possible.
+func (p *importer) typ(parent *types.Package, tname *types.Named) types.Type {
+ // if the type was seen before, i is its index (>= 0)
+ i := p.tagOrIndex()
+ if i >= 0 {
+ return p.typList[i]
+ }
+
+ // otherwise, i is the type tag (< 0)
+ switch i {
+ case namedTag:
+ // read type object
+ pos := p.pos()
+ parent, name := p.qualifiedName()
+ scope := parent.Scope()
+ obj := scope.Lookup(name)
+
+ // if the object doesn't exist yet, create and insert it
+ if obj == nil {
+ obj = types.NewTypeName(pos, parent, name, nil)
+ scope.Insert(obj)
+ }
+
+ if _, ok := obj.(*types.TypeName); !ok {
+ errorf("pkg = %s, name = %s => %s", parent, name, obj)
+ }
+
+ // associate new named type with obj if it doesn't exist yet
+ t0 := types.NewNamed(obj.(*types.TypeName), nil, nil)
+
+ // but record the existing type, if any
+ tname := obj.Type().(*types.Named) // tname is either t0 or the existing type
+ p.record(tname)
+
+ // read underlying type
+ t0.SetUnderlying(p.typ(parent, t0))
+
+ // interfaces don't have associated methods
+ if types.IsInterface(t0) {
+ return tname
+ }
+
+ // read associated methods
+ for i := p.int(); i > 0; i-- {
+ // TODO(gri) replace this with something closer to fieldName
+ pos := p.pos()
+ name := p.string()
+ if !exported(name) {
+ p.pkg()
+ }
+
+ recv, _ := p.paramList() // TODO(gri) do we need a full param list for the receiver?
+ params, isddd := p.paramList()
+ result, _ := p.paramList()
+ p.int() // go:nointerface pragma - discarded
+
+ sig := types.NewSignature(recv.At(0), params, result, isddd)
+ t0.AddMethod(types.NewFunc(pos, parent, name, sig))
+ }
+
+ return tname
+
+ case arrayTag:
+ t := new(types.Array)
+ if p.trackAllTypes {
+ p.record(t)
+ }
+
+ n := p.int64()
+ *t = *types.NewArray(p.typ(parent, nil), n)
+ return t
+
+ case sliceTag:
+ t := new(types.Slice)
+ if p.trackAllTypes {
+ p.record(t)
+ }
+
+ *t = *types.NewSlice(p.typ(parent, nil))
+ return t
+
+ case dddTag:
+ t := new(dddSlice)
+ if p.trackAllTypes {
+ p.record(t)
+ }
+
+ t.elem = p.typ(parent, nil)
+ return t
+
+ case structTag:
+ t := new(types.Struct)
+ if p.trackAllTypes {
+ p.record(t)
+ }
+
+ *t = *types.NewStruct(p.fieldList(parent))
+ return t
+
+ case pointerTag:
+ t := new(types.Pointer)
+ if p.trackAllTypes {
+ p.record(t)
+ }
+
+ *t = *types.NewPointer(p.typ(parent, nil))
+ return t
+
+ case signatureTag:
+ t := new(types.Signature)
+ if p.trackAllTypes {
+ p.record(t)
+ }
+
+ params, isddd := p.paramList()
+ result, _ := p.paramList()
+ *t = *types.NewSignature(nil, params, result, isddd)
+ return t
+
+ case interfaceTag:
+ // Create a dummy entry in the type list. This is safe because we
+ // cannot expect the interface type to appear in a cycle, as any
+ // such cycle must contain a named type which would have been
+ // first defined earlier.
+ // TODO(gri) Is this still true now that we have type aliases?
+ // See issue #23225.
+ n := len(p.typList)
+ if p.trackAllTypes {
+ p.record(nil)
+ }
+
+ var embeddeds []types.Type
+ for n := p.int(); n > 0; n-- {
+ p.pos()
+ embeddeds = append(embeddeds, p.typ(parent, nil))
+ }
+
+ t := newInterface(p.methodList(parent, tname), embeddeds)
+ p.interfaceList = append(p.interfaceList, t)
+ if p.trackAllTypes {
+ p.typList[n] = t
+ }
+ return t
+
+ case mapTag:
+ t := new(types.Map)
+ if p.trackAllTypes {
+ p.record(t)
+ }
+
+ key := p.typ(parent, nil)
+ val := p.typ(parent, nil)
+ *t = *types.NewMap(key, val)
+ return t
+
+ case chanTag:
+ t := new(types.Chan)
+ if p.trackAllTypes {
+ p.record(t)
+ }
+
+ dir := chanDir(p.int())
+ val := p.typ(parent, nil)
+ *t = *types.NewChan(dir, val)
+ return t
+
+ default:
+ errorf("unexpected type tag %d", i) // panics
+ panic("unreachable")
+ }
+}
+
+func chanDir(d int) types.ChanDir {
+ // tag values must match the constants in cmd/compile/internal/gc/go.go
+ switch d {
+ case 1 /* Crecv */ :
+ return types.RecvOnly
+ case 2 /* Csend */ :
+ return types.SendOnly
+ case 3 /* Cboth */ :
+ return types.SendRecv
+ default:
+ errorf("unexpected channel dir %d", d)
+ return 0
+ }
+}
+
+func (p *importer) fieldList(parent *types.Package) (fields []*types.Var, tags []string) {
+ if n := p.int(); n > 0 {
+ fields = make([]*types.Var, n)
+ tags = make([]string, n)
+ for i := range fields {
+ fields[i], tags[i] = p.field(parent)
+ }
+ }
+ return
+}
+
+func (p *importer) field(parent *types.Package) (*types.Var, string) {
+ pos := p.pos()
+ pkg, name, alias := p.fieldName(parent)
+ typ := p.typ(parent, nil)
+ tag := p.string()
+
+ anonymous := false
+ if name == "" {
+ // anonymous field - typ must be T or *T and T must be a type name
+ switch typ := deref(typ).(type) {
+ case *types.Basic: // basic types are named types
+ pkg = nil // // objects defined in Universe scope have no package
+ name = typ.Name()
+ case *types.Named:
+ name = typ.Obj().Name()
+ default:
+ errorf("named base type expected")
+ }
+ anonymous = true
+ } else if alias {
+ // anonymous field: we have an explicit name because it's an alias
+ anonymous = true
+ }
+
+ return types.NewField(pos, pkg, name, typ, anonymous), tag
+}
+
+func (p *importer) methodList(parent *types.Package, baseType *types.Named) (methods []*types.Func) {
+ if n := p.int(); n > 0 {
+ methods = make([]*types.Func, n)
+ for i := range methods {
+ methods[i] = p.method(parent, baseType)
+ }
+ }
+ return
+}
+
+func (p *importer) method(parent *types.Package, baseType *types.Named) *types.Func {
+ pos := p.pos()
+ pkg, name, _ := p.fieldName(parent)
+ // If we don't have a baseType, use a nil receiver.
+ // A receiver using the actual interface type (which
+ // we don't know yet) will be filled in when we call
+ // types.Interface.Complete.
+ var recv *types.Var
+ if baseType != nil {
+ recv = types.NewVar(token.NoPos, parent, "", baseType)
+ }
+ params, isddd := p.paramList()
+ result, _ := p.paramList()
+ sig := types.NewSignature(recv, params, result, isddd)
+ return types.NewFunc(pos, pkg, name, sig)
+}
+
+func (p *importer) fieldName(parent *types.Package) (pkg *types.Package, name string, alias bool) {
+ name = p.string()
+ pkg = parent
+ if pkg == nil {
+ // use the imported package instead
+ pkg = p.pkgList[0]
+ }
+ if p.version == 0 && name == "_" {
+ // version 0 didn't export a package for _ fields
+ return
+ }
+ switch name {
+ case "":
+ // 1) field name matches base type name and is exported: nothing to do
+ case "?":
+ // 2) field name matches base type name and is not exported: need package
+ name = ""
+ pkg = p.pkg()
+ case "@":
+ // 3) field name doesn't match type name (alias)
+ name = p.string()
+ alias = true
+ fallthrough
+ default:
+ if !exported(name) {
+ pkg = p.pkg()
+ }
+ }
+ return
+}
+
+func (p *importer) paramList() (*types.Tuple, bool) {
+ n := p.int()
+ if n == 0 {
+ return nil, false
+ }
+ // negative length indicates unnamed parameters
+ named := true
+ if n < 0 {
+ n = -n
+ named = false
+ }
+ // n > 0
+ params := make([]*types.Var, n)
+ isddd := false
+ for i := range params {
+ params[i], isddd = p.param(named)
+ }
+ return types.NewTuple(params...), isddd
+}
+
+func (p *importer) param(named bool) (*types.Var, bool) {
+ t := p.typ(nil, nil)
+ td, isddd := t.(*dddSlice)
+ if isddd {
+ t = types.NewSlice(td.elem)
+ }
+
+ var pkg *types.Package
+ var name string
+ if named {
+ name = p.string()
+ if name == "" {
+ errorf("expected named parameter")
+ }
+ if name != "_" {
+ pkg = p.pkg()
+ }
+ if i := strings.Index(name, "ยท"); i > 0 {
+ name = name[:i] // cut off gc-specific parameter numbering
+ }
+ }
+
+ // read and discard compiler-specific info
+ p.string()
+
+ return types.NewVar(token.NoPos, pkg, name, t), isddd
+}
+
+func exported(name string) bool {
+ ch, _ := utf8.DecodeRuneInString(name)
+ return unicode.IsUpper(ch)
+}
+
+func (p *importer) value() constant.Value {
+ switch tag := p.tagOrIndex(); tag {
+ case falseTag:
+ return constant.MakeBool(false)
+ case trueTag:
+ return constant.MakeBool(true)
+ case int64Tag:
+ return constant.MakeInt64(p.int64())
+ case floatTag:
+ return p.float()
+ case complexTag:
+ re := p.float()
+ im := p.float()
+ return constant.BinaryOp(re, token.ADD, constant.MakeImag(im))
+ case stringTag:
+ return constant.MakeString(p.string())
+ case unknownTag:
+ return constant.MakeUnknown()
+ default:
+ errorf("unexpected value tag %d", tag) // panics
+ panic("unreachable")
+ }
+}
+
+func (p *importer) float() constant.Value {
+ sign := p.int()
+ if sign == 0 {
+ return constant.MakeInt64(0)
+ }
+
+ exp := p.int()
+ mant := []byte(p.string()) // big endian
+
+ // remove leading 0's if any
+ for len(mant) > 0 && mant[0] == 0 {
+ mant = mant[1:]
+ }
+
+ // convert to little endian
+ // TODO(gri) go/constant should have a more direct conversion function
+ // (e.g., once it supports a big.Float based implementation)
+ for i, j := 0, len(mant)-1; i < j; i, j = i+1, j-1 {
+ mant[i], mant[j] = mant[j], mant[i]
+ }
+
+ // adjust exponent (constant.MakeFromBytes creates an integer value,
+ // but mant represents the mantissa bits such that 0.5 <= mant < 1.0)
+ exp -= len(mant) << 3
+ if len(mant) > 0 {
+ for msd := mant[len(mant)-1]; msd&0x80 == 0; msd <<= 1 {
+ exp++
+ }
+ }
+
+ x := constant.MakeFromBytes(mant)
+ switch {
+ case exp < 0:
+ d := constant.Shift(constant.MakeInt64(1), token.SHL, uint(-exp))
+ x = constant.BinaryOp(x, token.QUO, d)
+ case exp > 0:
+ x = constant.Shift(x, token.SHL, uint(exp))
+ }
+
+ if sign < 0 {
+ x = constant.UnaryOp(token.SUB, x, 0)
+ }
+ return x
+}
+
+// ----------------------------------------------------------------------------
+// Low-level decoders
+
+func (p *importer) tagOrIndex() int {
+ if p.debugFormat {
+ p.marker('t')
+ }
+
+ return int(p.rawInt64())
+}
+
+func (p *importer) int() int {
+ x := p.int64()
+ if int64(int(x)) != x {
+ errorf("exported integer too large")
+ }
+ return int(x)
+}
+
+func (p *importer) int64() int64 {
+ if p.debugFormat {
+ p.marker('i')
+ }
+
+ return p.rawInt64()
+}
+
+func (p *importer) path() string {
+ if p.debugFormat {
+ p.marker('p')
+ }
+ // if the path was seen before, i is its index (>= 0)
+ // (the empty string is at index 0)
+ i := p.rawInt64()
+ if i >= 0 {
+ return p.pathList[i]
+ }
+ // otherwise, i is the negative path length (< 0)
+ a := make([]string, -i)
+ for n := range a {
+ a[n] = p.string()
+ }
+ s := strings.Join(a, "/")
+ p.pathList = append(p.pathList, s)
+ return s
+}
+
+func (p *importer) string() string {
+ if p.debugFormat {
+ p.marker('s')
+ }
+ // if the string was seen before, i is its index (>= 0)
+ // (the empty string is at index 0)
+ i := p.rawInt64()
+ if i >= 0 {
+ return p.strList[i]
+ }
+ // otherwise, i is the negative string length (< 0)
+ if n := int(-i); n <= cap(p.buf) {
+ p.buf = p.buf[:n]
+ } else {
+ p.buf = make([]byte, n)
+ }
+ for i := range p.buf {
+ p.buf[i] = p.rawByte()
+ }
+ s := string(p.buf)
+ p.strList = append(p.strList, s)
+ return s
+}
+
+func (p *importer) marker(want byte) {
+ if got := p.rawByte(); got != want {
+ errorf("incorrect marker: got %c; want %c (pos = %d)", got, want, p.read)
+ }
+
+ pos := p.read
+ if n := int(p.rawInt64()); n != pos {
+ errorf("incorrect position: got %d; want %d", n, pos)
+ }
+}
+
+// rawInt64 should only be used by low-level decoders.
+func (p *importer) rawInt64() int64 {
+ i, err := binary.ReadVarint(p)
+ if err != nil {
+ errorf("read error: %v", err)
+ }
+ return i
+}
+
+// rawStringln should only be used to read the initial version string.
+func (p *importer) rawStringln(b byte) string {
+ p.buf = p.buf[:0]
+ for b != '\n' {
+ p.buf = append(p.buf, b)
+ b = p.rawByte()
+ }
+ return string(p.buf)
+}
+
+// needed for binary.ReadVarint in rawInt64
+func (p *importer) ReadByte() (byte, error) {
+ return p.rawByte(), nil
+}
+
+// byte is the bottleneck interface for reading p.data.
+// It unescapes '|' 'S' to '$' and '|' '|' to '|'.
+// rawByte should only be used by low-level decoders.
+func (p *importer) rawByte() byte {
+ b := p.data[0]
+ r := 1
+ if b == '|' {
+ b = p.data[1]
+ r = 2
+ switch b {
+ case 'S':
+ b = '$'
+ case '|':
+ // nothing to do
+ default:
+ errorf("unexpected escape sequence in export data")
+ }
+ }
+ p.data = p.data[r:]
+ p.read += r
+ return b
+
+}
+
+// ----------------------------------------------------------------------------
+// Export format
+
+// Tags. Must be < 0.
+const (
+ // Objects
+ packageTag = -(iota + 1)
+ constTag
+ typeTag
+ varTag
+ funcTag
+ endTag
+
+ // Types
+ namedTag
+ arrayTag
+ sliceTag
+ dddTag
+ structTag
+ pointerTag
+ signatureTag
+ interfaceTag
+ mapTag
+ chanTag
+
+ // Values
+ falseTag
+ trueTag
+ int64Tag
+ floatTag
+ fractionTag // not used by gc
+ complexTag
+ stringTag
+ nilTag // only used by gc (appears in exported inlined function bodies)
+ unknownTag // not used by gc (only appears in packages with errors)
+
+ // Type aliases
+ aliasTag
+)
+
+var predeclOnce sync.Once
+var predecl []types.Type // initialized lazily
+
+func predeclared() []types.Type {
+ predeclOnce.Do(func() {
+ // initialize lazily to be sure that all
+ // elements have been initialized before
+ predecl = []types.Type{ // basic types
+ types.Typ[types.Bool],
+ types.Typ[types.Int],
+ types.Typ[types.Int8],
+ types.Typ[types.Int16],
+ types.Typ[types.Int32],
+ types.Typ[types.Int64],
+ types.Typ[types.Uint],
+ types.Typ[types.Uint8],
+ types.Typ[types.Uint16],
+ types.Typ[types.Uint32],
+ types.Typ[types.Uint64],
+ types.Typ[types.Uintptr],
+ types.Typ[types.Float32],
+ types.Typ[types.Float64],
+ types.Typ[types.Complex64],
+ types.Typ[types.Complex128],
+ types.Typ[types.String],
+
+ // basic type aliases
+ types.Universe.Lookup("byte").Type(),
+ types.Universe.Lookup("rune").Type(),
+
+ // error
+ types.Universe.Lookup("error").Type(),
+
+ // untyped types
+ types.Typ[types.UntypedBool],
+ types.Typ[types.UntypedInt],
+ types.Typ[types.UntypedRune],
+ types.Typ[types.UntypedFloat],
+ types.Typ[types.UntypedComplex],
+ types.Typ[types.UntypedString],
+ types.Typ[types.UntypedNil],
+
+ // package unsafe
+ types.Typ[types.UnsafePointer],
+
+ // invalid type
+ types.Typ[types.Invalid], // only appears in packages with errors
+
+ // used internally by gc; never used by this package or in .a files
+ anyType{},
+ }
+ predecl = append(predecl, additionalPredeclared()...)
+ })
+ return predecl
+}
+
+type anyType struct{}
+
+func (t anyType) Underlying() types.Type { return t }
+func (t anyType) String() string { return "any" }
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-18 14:18:10 +0000