Description: use gcimporter15 again Author: Thorsten Alteholz and upstream diff --git a/compiler/vendor/golang.org/x/tools/go/gcimporter15/bexport.go b/compiler/vendor/golang.org/x/tools/go/gcimporter15/bexport.go new file mode 100644 index 0000000..cbf8bc0 --- /dev/null +++ b/compiler/vendor/golang.org/x/tools/go/gcimporter15/bexport.go @@ -0,0 +1,828 @@ +// Copyright 2016 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. + +// Binary package export. +// This file was derived from $GOROOT/src/cmd/compile/internal/gc/bexport.go; +// see that file for specification of the format. + +package gcimporter + +import ( + "bytes" + "encoding/binary" + "fmt" + "go/ast" + "go/constant" + "go/token" + "go/types" + "log" + "math" + "math/big" + "sort" + "strings" +) + +// If debugFormat is set, each integer and string value is preceded by a marker +// and position information in the encoding. This mechanism permits an importer +// to recognize immediately when it is out of sync. The importer recognizes this +// mode automatically (i.e., it can import export data produced with debugging +// support even if debugFormat is not set at the time of import). This mode will +// lead to massively larger export data (by a factor of 2 to 3) and should only +// be enabled during development and debugging. +// +// NOTE: This flag is the first flag to enable if importing dies because of +// (suspected) format errors, and whenever a change is made to the format. +const debugFormat = false // default: false + +// If trace is set, debugging output is printed to std out. +const trace = false // default: false + +// Current export format version. Increase with each format change. +// 4: type name objects support type aliases, uses aliasTag +// 3: Go1.8 encoding (same as version 2, aliasTag defined but never used) +// 2: removed unused bool in ODCL export (compiler only) +// 1: header format change (more regular), export package for _ struct fields +// 0: Go1.7 encoding +const exportVersion = 4 + +// trackAllTypes enables cycle tracking for all types, not just named +// types. The existing compiler invariants assume that unnamed types +// that are not completely set up are not used, or else there are spurious +// errors. +// If disabled, only named types are tracked, possibly leading to slightly +// less efficient encoding in rare cases. It also prevents the export of +// some corner-case type declarations (but those are not handled correctly +// with with the textual export format either). +// TODO(gri) enable and remove once issues caused by it are fixed +const trackAllTypes = false + +type exporter struct { + fset *token.FileSet + out bytes.Buffer + + // object -> index maps, indexed in order of serialization + strIndex map[string]int + pkgIndex map[*types.Package]int + typIndex map[types.Type]int + + // position encoding + posInfoFormat bool + prevFile string + prevLine int + + // debugging support + written int // bytes written + indent int // for trace +} + +// BExportData returns binary export data for pkg. +// If no file set is provided, position info will be missing. +func BExportData(fset *token.FileSet, pkg *types.Package) []byte { + p := exporter{ + fset: fset, + strIndex: map[string]int{"": 0}, // empty string is mapped to 0 + pkgIndex: make(map[*types.Package]int), + typIndex: make(map[types.Type]int), + posInfoFormat: true, // TODO(gri) might become a flag, eventually + } + + // write version info + // The version string must start with "version %d" where %d is the version + // number. Additional debugging information may follow after a blank; that + // text is ignored by the importer. + p.rawStringln(fmt.Sprintf("version %d", exportVersion)) + var debug string + if debugFormat { + debug = "debug" + } + p.rawStringln(debug) // cannot use p.bool since it's affected by debugFormat; also want to see this clearly + p.bool(trackAllTypes) + p.bool(p.posInfoFormat) + + // --- generic export data --- + + // populate type map with predeclared "known" types + for index, typ := range predeclared { + p.typIndex[typ] = index + } + if len(p.typIndex) != len(predeclared) { + log.Fatalf("gcimporter: duplicate entries in type map?") + } + + // write package data + p.pkg(pkg, true) + if trace { + p.tracef("\n") + } + + // write objects + objcount := 0 + scope := pkg.Scope() + for _, name := range scope.Names() { + if !ast.IsExported(name) { + continue + } + if trace { + p.tracef("\n") + } + p.obj(scope.Lookup(name)) + objcount++ + } + + // indicate end of list + if trace { + p.tracef("\n") + } + p.tag(endTag) + + // for self-verification only (redundant) + p.int(objcount) + + if trace { + p.tracef("\n") + } + + // --- end of export data --- + + return p.out.Bytes() +} + +func (p *exporter) pkg(pkg *types.Package, emptypath bool) { + if pkg == nil { + log.Fatalf("gcimporter: unexpected nil pkg") + } + + // if we saw the package before, write its index (>= 0) + if i, ok := p.pkgIndex[pkg]; ok { + p.index('P', i) + return + } + + // otherwise, remember the package, write the package tag (< 0) and package data + if trace { + p.tracef("P%d = { ", len(p.pkgIndex)) + defer p.tracef("} ") + } + p.pkgIndex[pkg] = len(p.pkgIndex) + + p.tag(packageTag) + p.string(pkg.Name()) + if emptypath { + p.string("") + } else { + p.string(pkg.Path()) + } +} + +func (p *exporter) obj(obj types.Object) { + switch obj := obj.(type) { + case *types.Const: + p.tag(constTag) + p.pos(obj) + p.qualifiedName(obj) + p.typ(obj.Type()) + p.value(obj.Val()) + + case *types.TypeName: + if isAlias(obj) { + p.tag(aliasTag) + p.pos(obj) + p.qualifiedName(obj) + } else { + p.tag(typeTag) + } + p.typ(obj.Type()) + + case *types.Var: + p.tag(varTag) + p.pos(obj) + p.qualifiedName(obj) + p.typ(obj.Type()) + + case *types.Func: + p.tag(funcTag) + p.pos(obj) + p.qualifiedName(obj) + sig := obj.Type().(*types.Signature) + p.paramList(sig.Params(), sig.Variadic()) + p.paramList(sig.Results(), false) + + default: + log.Fatalf("gcimporter: unexpected object %v (%T)", obj, obj) + } +} + +func (p *exporter) pos(obj types.Object) { + if !p.posInfoFormat { + return + } + + file, line := p.fileLine(obj) + if file == p.prevFile { + // common case: write line delta + // delta == 0 means different file or no line change + delta := line - p.prevLine + p.int(delta) + if delta == 0 { + p.int(-1) // -1 means no file change + } + } else { + // different file + p.int(0) + // Encode filename as length of common prefix with previous + // filename, followed by (possibly empty) suffix. Filenames + // frequently share path prefixes, so this can save a lot + // of space and make export data size less dependent on file + // path length. The suffix is unlikely to be empty because + // file names tend to end in ".go". + n := commonPrefixLen(p.prevFile, file) + p.int(n) // n >= 0 + p.string(file[n:]) // write suffix only + p.prevFile = file + p.int(line) + } + p.prevLine = line +} + +func (p *exporter) fileLine(obj types.Object) (file string, line int) { + if p.fset != nil { + pos := p.fset.Position(obj.Pos()) + file = pos.Filename + line = pos.Line + } + return +} + +func commonPrefixLen(a, b string) int { + if len(a) > len(b) { + a, b = b, a + } + // len(a) <= len(b) + i := 0 + for i < len(a) && a[i] == b[i] { + i++ + } + return i +} + +func (p *exporter) qualifiedName(obj types.Object) { + p.string(obj.Name()) + p.pkg(obj.Pkg(), false) +} + +func (p *exporter) typ(t types.Type) { + if t == nil { + log.Fatalf("gcimporter: nil type") + } + + // Possible optimization: Anonymous pointer types *T where + // T is a named type are common. We could canonicalize all + // such types *T to a single type PT = *T. This would lead + // to at most one *T entry in typIndex, and all future *T's + // would be encoded as the respective index directly. Would + // save 1 byte (pointerTag) per *T and reduce the typIndex + // size (at the cost of a canonicalization map). We can do + // this later, without encoding format change. + + // if we saw the type before, write its index (>= 0) + if i, ok := p.typIndex[t]; ok { + p.index('T', i) + return + } + + // otherwise, remember the type, write the type tag (< 0) and type data + if trackAllTypes { + if trace { + p.tracef("T%d = {>\n", len(p.typIndex)) + defer p.tracef("<\n} ") + } + p.typIndex[t] = len(p.typIndex) + } + + switch t := t.(type) { + case *types.Named: + if !trackAllTypes { + // if we don't track all types, track named types now + p.typIndex[t] = len(p.typIndex) + } + + p.tag(namedTag) + p.pos(t.Obj()) + p.qualifiedName(t.Obj()) + p.typ(t.Underlying()) + if !types.IsInterface(t) { + p.assocMethods(t) + } + + case *types.Array: + p.tag(arrayTag) + p.int64(t.Len()) + p.typ(t.Elem()) + + case *types.Slice: + p.tag(sliceTag) + p.typ(t.Elem()) + + case *dddSlice: + p.tag(dddTag) + p.typ(t.elem) + + case *types.Struct: + p.tag(structTag) + p.fieldList(t) + + case *types.Pointer: + p.tag(pointerTag) + p.typ(t.Elem()) + + case *types.Signature: + p.tag(signatureTag) + p.paramList(t.Params(), t.Variadic()) + p.paramList(t.Results(), false) + + case *types.Interface: + p.tag(interfaceTag) + p.iface(t) + + case *types.Map: + p.tag(mapTag) + p.typ(t.Key()) + p.typ(t.Elem()) + + case *types.Chan: + p.tag(chanTag) + p.int(int(3 - t.Dir())) // hack + p.typ(t.Elem()) + + default: + log.Fatalf("gcimporter: unexpected type %T: %s", t, t) + } +} + +func (p *exporter) assocMethods(named *types.Named) { + // Sort methods (for determinism). + var methods []*types.Func + for i := 0; i < named.NumMethods(); i++ { + methods = append(methods, named.Method(i)) + } + sort.Sort(methodsByName(methods)) + + p.int(len(methods)) + + if trace && methods != nil { + p.tracef("associated methods {>\n") + } + + for i, m := range methods { + if trace && i > 0 { + p.tracef("\n") + } + + p.pos(m) + name := m.Name() + p.string(name) + if !exported(name) { + p.pkg(m.Pkg(), false) + } + + sig := m.Type().(*types.Signature) + p.paramList(types.NewTuple(sig.Recv()), false) + p.paramList(sig.Params(), sig.Variadic()) + p.paramList(sig.Results(), false) + p.int(0) // dummy value for go:nointerface pragma - ignored by importer + } + + if trace && methods != nil { + p.tracef("<\n} ") + } +} + +type methodsByName []*types.Func + +func (x methodsByName) Len() int { return len(x) } +func (x methodsByName) Swap(i, j int) { x[i], x[j] = x[j], x[i] } +func (x methodsByName) Less(i, j int) bool { return x[i].Name() < x[j].Name() } + +func (p *exporter) fieldList(t *types.Struct) { + if trace && t.NumFields() > 0 { + p.tracef("fields {>\n") + defer p.tracef("<\n} ") + } + + p.int(t.NumFields()) + for i := 0; i < t.NumFields(); i++ { + if trace && i > 0 { + p.tracef("\n") + } + p.field(t.Field(i)) + p.string(t.Tag(i)) + } +} + +func (p *exporter) field(f *types.Var) { + if !f.IsField() { + log.Fatalf("gcimporter: field expected") + } + + p.pos(f) + p.fieldName(f) + p.typ(f.Type()) +} + +func (p *exporter) iface(t *types.Interface) { + // TODO(gri): enable importer to load embedded interfaces, + // then emit Embeddeds and ExplicitMethods separately here. + p.int(0) + + n := t.NumMethods() + if trace && n > 0 { + p.tracef("methods {>\n") + defer p.tracef("<\n} ") + } + p.int(n) + for i := 0; i < n; i++ { + if trace && i > 0 { + p.tracef("\n") + } + p.method(t.Method(i)) + } +} + +func (p *exporter) method(m *types.Func) { + sig := m.Type().(*types.Signature) + if sig.Recv() == nil { + log.Fatalf("gcimporter: method expected") + } + + p.pos(m) + p.string(m.Name()) + if m.Name() != "_" && !ast.IsExported(m.Name()) { + p.pkg(m.Pkg(), false) + } + + // interface method; no need to encode receiver. + p.paramList(sig.Params(), sig.Variadic()) + p.paramList(sig.Results(), false) +} + +func (p *exporter) fieldName(f *types.Var) { + name := f.Name() + + if f.Anonymous() { + // anonymous field - we distinguish between 3 cases: + // 1) field name matches base type name and is exported + // 2) field name matches base type name and is not exported + // 3) field name doesn't match base type name (alias name) + bname := basetypeName(f.Type()) + if name == bname { + if ast.IsExported(name) { + name = "" // 1) we don't need to know the field name or package + } else { + name = "?" // 2) use unexported name "?" to force package export + } + } else { + // 3) indicate alias and export name as is + // (this requires an extra "@" but this is a rare case) + p.string("@") + } + } + + p.string(name) + if name != "" && !ast.IsExported(name) { + p.pkg(f.Pkg(), false) + } +} + +func basetypeName(typ types.Type) string { + switch typ := deref(typ).(type) { + case *types.Basic: + return typ.Name() + case *types.Named: + return typ.Obj().Name() + default: + return "" // unnamed type + } +} + +func (p *exporter) paramList(params *types.Tuple, variadic bool) { + // use negative length to indicate unnamed parameters + // (look at the first parameter only since either all + // names are present or all are absent) + n := params.Len() + if n > 0 && params.At(0).Name() == "" { + n = -n + } + p.int(n) + for i := 0; i < params.Len(); i++ { + q := params.At(i) + t := q.Type() + if variadic && i == params.Len()-1 { + t = &dddSlice{t.(*types.Slice).Elem()} + } + p.typ(t) + if n > 0 { + name := q.Name() + p.string(name) + if name != "_" { + p.pkg(q.Pkg(), false) + } + } + p.string("") // no compiler-specific info + } +} + +func (p *exporter) value(x constant.Value) { + if trace { + p.tracef("= ") + } + + switch x.Kind() { + case constant.Bool: + tag := falseTag + if constant.BoolVal(x) { + tag = trueTag + } + p.tag(tag) + + case constant.Int: + if v, exact := constant.Int64Val(x); exact { + // common case: x fits into an int64 - use compact encoding + p.tag(int64Tag) + p.int64(v) + return + } + // uncommon case: large x - use float encoding + // (powers of 2 will be encoded efficiently with exponent) + p.tag(floatTag) + p.float(constant.ToFloat(x)) + + case constant.Float: + p.tag(floatTag) + p.float(x) + + case constant.Complex: + p.tag(complexTag) + p.float(constant.Real(x)) + p.float(constant.Imag(x)) + + case constant.String: + p.tag(stringTag) + p.string(constant.StringVal(x)) + + case constant.Unknown: + // package contains type errors + p.tag(unknownTag) + + default: + log.Fatalf("gcimporter: unexpected value %v (%T)", x, x) + } +} + +func (p *exporter) float(x constant.Value) { + if x.Kind() != constant.Float { + log.Fatalf("gcimporter: unexpected constant %v, want float", x) + } + // extract sign (there is no -0) + sign := constant.Sign(x) + if sign == 0 { + // x == 0 + p.int(0) + return + } + // x != 0 + + var f big.Float + if v, exact := constant.Float64Val(x); exact { + // float64 + f.SetFloat64(v) + } else if num, denom := constant.Num(x), constant.Denom(x); num.Kind() == constant.Int { + // TODO(gri): add big.Rat accessor to constant.Value. + r := valueToRat(num) + f.SetRat(r.Quo(r, valueToRat(denom))) + } else { + // Value too large to represent as a fraction => inaccessible. + // TODO(gri): add big.Float accessor to constant.Value. + f.SetFloat64(math.MaxFloat64) // FIXME + } + + // extract exponent such that 0.5 <= m < 1.0 + var m big.Float + exp := f.MantExp(&m) + + // extract mantissa as *big.Int + // - set exponent large enough so mant satisfies mant.IsInt() + // - get *big.Int from mant + m.SetMantExp(&m, int(m.MinPrec())) + mant, acc := m.Int(nil) + if acc != big.Exact { + log.Fatalf("gcimporter: internal error") + } + + p.int(sign) + p.int(exp) + p.string(string(mant.Bytes())) +} + +func valueToRat(x constant.Value) *big.Rat { + // Convert little-endian to big-endian. + // I can't believe this is necessary. + bytes := constant.Bytes(x) + for i := 0; i < len(bytes)/2; i++ { + bytes[i], bytes[len(bytes)-1-i] = bytes[len(bytes)-1-i], bytes[i] + } + return new(big.Rat).SetInt(new(big.Int).SetBytes(bytes)) +} + +func (p *exporter) bool(b bool) bool { + if trace { + p.tracef("[") + defer p.tracef("= %v] ", b) + } + + x := 0 + if b { + x = 1 + } + p.int(x) + return b +} + +// ---------------------------------------------------------------------------- +// Low-level encoders + +func (p *exporter) index(marker byte, index int) { + if index < 0 { + log.Fatalf("gcimporter: invalid index < 0") + } + if debugFormat { + p.marker('t') + } + if trace { + p.tracef("%c%d ", marker, index) + } + p.rawInt64(int64(index)) +} + +func (p *exporter) tag(tag int) { + if tag >= 0 { + log.Fatalf("gcimporter: invalid tag >= 0") + } + if debugFormat { + p.marker('t') + } + if trace { + p.tracef("%s ", tagString[-tag]) + } + p.rawInt64(int64(tag)) +} + +func (p *exporter) int(x int) { + p.int64(int64(x)) +} + +func (p *exporter) int64(x int64) { + if debugFormat { + p.marker('i') + } + if trace { + p.tracef("%d ", x) + } + p.rawInt64(x) +} + +func (p *exporter) string(s string) { + if debugFormat { + p.marker('s') + } + if trace { + p.tracef("%q ", s) + } + // if we saw the string before, write its index (>= 0) + // (the empty string is mapped to 0) + if i, ok := p.strIndex[s]; ok { + p.rawInt64(int64(i)) + return + } + // otherwise, remember string and write its negative length and bytes + p.strIndex[s] = len(p.strIndex) + p.rawInt64(-int64(len(s))) + for i := 0; i < len(s); i++ { + p.rawByte(s[i]) + } +} + +// marker emits a marker byte and position information which makes +// it easy for a reader to detect if it is "out of sync". Used for +// debugFormat format only. +func (p *exporter) marker(m byte) { + p.rawByte(m) + // Enable this for help tracking down the location + // of an incorrect marker when running in debugFormat. + if false && trace { + p.tracef("#%d ", p.written) + } + p.rawInt64(int64(p.written)) +} + +// rawInt64 should only be used by low-level encoders. +func (p *exporter) rawInt64(x int64) { + var tmp [binary.MaxVarintLen64]byte + n := binary.PutVarint(tmp[:], x) + for i := 0; i < n; i++ { + p.rawByte(tmp[i]) + } +} + +// rawStringln should only be used to emit the initial version string. +func (p *exporter) rawStringln(s string) { + for i := 0; i < len(s); i++ { + p.rawByte(s[i]) + } + p.rawByte('\n') +} + +// rawByte is the bottleneck interface to write to p.out. +// rawByte escapes b as follows (any encoding does that +// hides '$'): +// +// '$' => '|' 'S' +// '|' => '|' '|' +// +// Necessary so other tools can find the end of the +// export data by searching for "$$". +// rawByte should only be used by low-level encoders. +func (p *exporter) rawByte(b byte) { + switch b { + case '$': + // write '$' as '|' 'S' + b = 'S' + fallthrough + case '|': + // write '|' as '|' '|' + p.out.WriteByte('|') + p.written++ + } + p.out.WriteByte(b) + p.written++ +} + +// tracef is like fmt.Printf but it rewrites the format string +// to take care of indentation. +func (p *exporter) tracef(format string, args ...interface{}) { + if strings.ContainsAny(format, "<>\n") { + var buf bytes.Buffer + for i := 0; i < len(format); i++ { + // no need to deal with runes + ch := format[i] + switch ch { + case '>': + p.indent++ + continue + case '<': + p.indent-- + continue + } + buf.WriteByte(ch) + if ch == '\n' { + for j := p.indent; j > 0; j-- { + buf.WriteString(". ") + } + } + } + format = buf.String() + } + fmt.Printf(format, args...) +} + +// Debugging support. +// (tagString is only used when tracing is enabled) +var tagString = [...]string{ + // Packages + -packageTag: "package", + + // Types + -namedTag: "named type", + -arrayTag: "array", + -sliceTag: "slice", + -dddTag: "ddd", + -structTag: "struct", + -pointerTag: "pointer", + -signatureTag: "signature", + -interfaceTag: "interface", + -mapTag: "map", + -chanTag: "chan", + + // Values + -falseTag: "false", + -trueTag: "true", + -int64Tag: "int64", + -floatTag: "float", + -fractionTag: "fraction", + -complexTag: "complex", + -stringTag: "string", + -unknownTag: "unknown", + + // Type aliases + -aliasTag: "alias", +} diff --git a/compiler/vendor/golang.org/x/tools/go/gcimporter15/bimport.go b/compiler/vendor/golang.org/x/tools/go/gcimporter15/bimport.go new file mode 100644 index 0000000..6709e43 --- /dev/null +++ b/compiler/vendor/golang.org/x/tools/go/gcimporter15/bimport.go @@ -0,0 +1,996 @@ +// 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 + fset *token.FileSet + files map[string]*token.File + + // 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 + defer func() { + if e := recover(); e != nil { + // The package (filename) causing the problem is added to this + // error by a wrapper in the caller (Import in gcimporter.go). + // Return a (possibly nil or incomplete) package unchanged (see #16088). + err = fmt.Errorf("cannot import, possibly version skew (%v) - reinstall package", e) + } + }() + + p := importer{ + imports: imports, + data: data, + importpath: path, + version: -1, // unknown version + strList: []string{""}, // empty string is mapped to 0 + pathList: []string{""}, // empty string is mapped to 0 + fset: fset, + files: make(map[string]*token.File), + } + + // 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" { + p.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 { + p.version = v + } + } + } + + // read version specific flags - extend as necessary + switch p.version { + // case 7: + // ... + // fallthrough + case 6, 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 export 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/compiler/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) + 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) + p.declare(types.NewTypeName(pos, pkg, name, typ)) + + case typeTag: + p.typ(nil) + + case varTag: + pos := p.pos() + pkg, name := p.qualifiedName() + typ := p.typ(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 + + // Synthesize a token.Pos + + // Since we don't know the set of needed file positions, we + // reserve maxlines positions per file. + const maxlines = 64 * 1024 + f := p.files[file] + if f == nil { + f = p.fset.AddFile(file, -1, maxlines) + p.files[file] = f + // Allocate the fake linebreak indices on first use. + // TODO(adonovan): opt: save ~512KB using a more complex scheme? + fakeLinesOnce.Do(func() { + fakeLines = make([]int, maxlines) + for i := range fakeLines { + fakeLines[i] = i + } + }) + f.SetLines(fakeLines) + } + + if line > maxlines { + line = 1 + } + + // Treat the file as if it contained only newlines + // and column=1: use the line number as the offset. + return f.Pos(line - 1) +} + +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. +func (p *importer) typ(parent *types.Package) 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 + t := obj.Type().(*types.Named) + p.record(t) + + // read underlying type + t0.SetUnderlying(p.typ(parent)) + + // interfaces don't have associated methods + if types.IsInterface(t0) { + return t + } + + // 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 t + + case arrayTag: + t := new(types.Array) + if p.trackAllTypes { + p.record(t) + } + + n := p.int64() + *t = *types.NewArray(p.typ(parent), n) + return t + + case sliceTag: + t := new(types.Slice) + if p.trackAllTypes { + p.record(t) + } + + *t = *types.NewSlice(p.typ(parent)) + return t + + case dddTag: + t := new(dddSlice) + if p.trackAllTypes { + p.record(t) + } + + t.elem = p.typ(parent) + 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)) + 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. + n := len(p.typList) + if p.trackAllTypes { + p.record(nil) + } + + var embeddeds []*types.Named + for n := p.int(); n > 0; n-- { + p.pos() + embeddeds = append(embeddeds, p.typ(parent).(*types.Named)) + } + + t := types.NewInterface(p.methodList(parent), 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) + val := p.typ(parent) + *t = *types.NewMap(key, val) + return t + + case chanTag: + t := new(types.Chan) + if p.trackAllTypes { + p.record(t) + } + + var dir types.ChanDir + // tag values must match the constants in cmd/compile/internal/gc/go.go + switch d := p.int(); d { + case 1 /* Crecv */ : + dir = types.RecvOnly + case 2 /* Csend */ : + dir = types.SendOnly + case 3 /* Cboth */ : + dir = types.SendRecv + default: + errorf("unexpected channel dir %d", d) + } + val := p.typ(parent) + *t = *types.NewChan(dir, val) + return t + + default: + errorf("unexpected type tag %d", i) // panics + panic("unreachable") + } +} + +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) + 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) (methods []*types.Func) { + if n := p.int(); n > 0 { + methods = make([]*types.Func, n) + for i := range methods { + methods[i] = p.method(parent) + } + } + return +} + +func (p *importer) method(parent *types.Package) *types.Func { + pos := p.pos() + pkg, name, _ := p.fieldName(parent) + params, isddd := p.paramList() + result, _ := p.paramList() + sig := types.NewSignature(nil, 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) + 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, "·"); 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 predeclared = []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{}, +} + +type anyType struct{} + +func (t anyType) Underlying() types.Type { return t } +func (t anyType) String() string { return "any" } diff --git a/compiler/vendor/golang.org/x/tools/go/gcimporter15/exportdata.go b/compiler/vendor/golang.org/x/tools/go/gcimporter15/exportdata.go new file mode 100644 index 0000000..f33dc56 --- /dev/null +++ b/compiler/vendor/golang.org/x/tools/go/gcimporter15/exportdata.go @@ -0,0 +1,93 @@ +// Copyright 2011 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/exportdata.go. + +// This file implements FindExportData. + +package gcimporter + +import ( + "bufio" + "fmt" + "io" + "strconv" + "strings" +) + +func readGopackHeader(r *bufio.Reader) (name string, size int, err error) { + // See $GOROOT/include/ar.h. + hdr := make([]byte, 16+12+6+6+8+10+2) + _, err = io.ReadFull(r, hdr) + if err != nil { + return + } + // leave for debugging + if false { + fmt.Printf("header: %s", hdr) + } + s := strings.TrimSpace(string(hdr[16+12+6+6+8:][:10])) + size, err = strconv.Atoi(s) + if err != nil || hdr[len(hdr)-2] != '`' || hdr[len(hdr)-1] != '\n' { + err = fmt.Errorf("invalid archive header") + return + } + name = strings.TrimSpace(string(hdr[:16])) + return +} + +// FindExportData positions the reader r at the beginning of the +// export data section of an underlying GC-created object/archive +// file by reading from it. The reader must be positioned at the +// start of the file before calling this function. The hdr result +// is the string before the export data, either "$$" or "$$B". +// +func FindExportData(r *bufio.Reader) (hdr string, err error) { + // Read first line to make sure this is an object file. + line, err := r.ReadSlice('\n') + if err != nil { + err = fmt.Errorf("can't find export data (%v)", err) + return + } + + if string(line) == "!\n" { + // Archive file. Scan to __.PKGDEF. + var name string + if name, _, err = readGopackHeader(r); err != nil { + return + } + + // First entry should be __.PKGDEF. + if name != "__.PKGDEF" { + err = fmt.Errorf("go archive is missing __.PKGDEF") + return + } + + // Read first line of __.PKGDEF data, so that line + // is once again the first line of the input. + if line, err = r.ReadSlice('\n'); err != nil { + err = fmt.Errorf("can't find export data (%v)", err) + return + } + } + + // Now at __.PKGDEF in archive or still at beginning of file. + // Either way, line should begin with "go object ". + if !strings.HasPrefix(string(line), "go object ") { + err = fmt.Errorf("not a Go object file") + return + } + + // Skip over object header to export data. + // Begins after first line starting with $$. + for line[0] != '$' { + if line, err = r.ReadSlice('\n'); err != nil { + err = fmt.Errorf("can't find export data (%v)", err) + return + } + } + hdr = string(line) + + return +} diff --git a/compiler/vendor/golang.org/x/tools/go/gcimporter15/gcimporter.go b/compiler/vendor/golang.org/x/tools/go/gcimporter15/gcimporter.go new file mode 100644 index 0000000..6fbc9d7 --- /dev/null +++ b/compiler/vendor/golang.org/x/tools/go/gcimporter15/gcimporter.go @@ -0,0 +1,1041 @@ +// Copyright 2011 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 $GOROOT/src/go/internal/gcimporter/gcimporter.go, +// but it also contains the original source-based importer code for Go1.6. +// Once we stop supporting 1.6, we can remove that code. + +// Package gcimporter15 provides various functions for reading +// gc-generated object files that can be used to implement the +// Importer interface defined by the Go 1.5 standard library package. +// +// Deprecated: this package will be deleted in October 2017. +// New code should use golang.org/x/tools/go/gcexportdata. +// +package gcimporter // import "golang.org/x/tools/go/gcimporter15" + +import ( + "bufio" + "errors" + "fmt" + "go/build" + exact "go/constant" + "go/token" + "go/types" + "io" + "io/ioutil" + "os" + "path/filepath" + "sort" + "strconv" + "strings" + "text/scanner" +) + +// debugging/development support +const debug = false + +var pkgExts = [...]string{".a", ".o"} + +// FindPkg returns the filename and unique package id for an import +// path based on package information provided by build.Import (using +// the build.Default build.Context). A relative srcDir is interpreted +// relative to the current working directory. +// If no file was found, an empty filename is returned. +// +func FindPkg(path, srcDir string) (filename, id string) { + if path == "" { + return + } + + var noext string + switch { + default: + // "x" -> "$GOPATH/pkg/$GOOS_$GOARCH/x.ext", "x" + // Don't require the source files to be present. + if abs, err := filepath.Abs(srcDir); err == nil { // see issue 14282 + srcDir = abs + } + bp, _ := build.Import(path, srcDir, build.FindOnly|build.AllowBinary) + if bp.PkgObj == "" { + return + } + noext = strings.TrimSuffix(bp.PkgObj, ".a") + id = bp.ImportPath + + case build.IsLocalImport(path): + // "./x" -> "/this/directory/x.ext", "/this/directory/x" + noext = filepath.Join(srcDir, path) + id = noext + + case filepath.IsAbs(path): + // for completeness only - go/build.Import + // does not support absolute imports + // "/x" -> "/x.ext", "/x" + noext = path + id = path + } + + if false { // for debugging + if path != id { + fmt.Printf("%s -> %s\n", path, id) + } + } + + // try extensions + for _, ext := range pkgExts { + filename = noext + ext + if f, err := os.Stat(filename); err == nil && !f.IsDir() { + return + } + } + + filename = "" // not found + return +} + +// ImportData imports a package by reading the gc-generated export data, +// adds the corresponding package object to the packages map indexed by id, +// and returns the object. +// +// The packages map must contains all packages already imported. The data +// reader position must be the beginning of the export data section. The +// filename is only used in error messages. +// +// If packages[id] contains the completely imported package, that package +// can be used directly, and there is no need to call this function (but +// there is also no harm but for extra time used). +// +func ImportData(packages map[string]*types.Package, filename, id string, data io.Reader) (pkg *types.Package, err error) { + // support for parser error handling + defer func() { + switch r := recover().(type) { + case nil: + // nothing to do + case importError: + err = r + default: + panic(r) // internal error + } + }() + + var p parser + p.init(filename, id, data, packages) + pkg = p.parseExport() + + return +} + +// Import imports a gc-generated package given its import path and srcDir, adds +// the corresponding package object to the packages map, and returns the object. +// The packages map must contain all packages already imported. +// +func Import(packages map[string]*types.Package, path, srcDir string) (pkg *types.Package, err error) { + filename, id := FindPkg(path, srcDir) + if filename == "" { + if path == "unsafe" { + return types.Unsafe, nil + } + err = fmt.Errorf("can't find import: %s", id) + return + } + + // no need to re-import if the package was imported completely before + if pkg = packages[id]; pkg != nil && pkg.Complete() { + return + } + + // open file + f, err := os.Open(filename) + if err != nil { + return + } + defer func() { + f.Close() + if err != nil { + // add file name to error + err = fmt.Errorf("reading export data: %s: %v", filename, err) + } + }() + + var hdr string + buf := bufio.NewReader(f) + if hdr, err = FindExportData(buf); err != nil { + return + } + + switch hdr { + case "$$\n": + return ImportData(packages, filename, id, buf) + case "$$B\n": + var data []byte + data, err = ioutil.ReadAll(buf) + if err == nil { + fset := token.NewFileSet() + _, pkg, err = BImportData(fset, packages, data, id) + return + } + default: + err = fmt.Errorf("unknown export data header: %q", hdr) + } + + return +} + +// ---------------------------------------------------------------------------- +// Parser + +// TODO(gri) Imported objects don't have position information. +// Ideally use the debug table line info; alternatively +// create some fake position (or the position of the +// import). That way error messages referring to imported +// objects can print meaningful information. + +// parser parses the exports inside a gc compiler-produced +// object/archive file and populates its scope with the results. +type parser struct { + scanner scanner.Scanner + tok rune // current token + lit string // literal string; only valid for Ident, Int, String tokens + id string // package id of imported package + sharedPkgs map[string]*types.Package // package id -> package object (across importer) + localPkgs map[string]*types.Package // package id -> package object (just this package) +} + +func (p *parser) init(filename, id string, src io.Reader, packages map[string]*types.Package) { + p.scanner.Init(src) + p.scanner.Error = func(_ *scanner.Scanner, msg string) { p.error(msg) } + p.scanner.Mode = scanner.ScanIdents | scanner.ScanInts | scanner.ScanChars | scanner.ScanStrings | scanner.ScanComments | scanner.SkipComments + p.scanner.Whitespace = 1<<'\t' | 1<<' ' + p.scanner.Filename = filename // for good error messages + p.next() + p.id = id + p.sharedPkgs = packages + if debug { + // check consistency of packages map + for _, pkg := range packages { + if pkg.Name() == "" { + fmt.Printf("no package name for %s\n", pkg.Path()) + } + } + } +} + +func (p *parser) next() { + p.tok = p.scanner.Scan() + switch p.tok { + case scanner.Ident, scanner.Int, scanner.Char, scanner.String, '·': + p.lit = p.scanner.TokenText() + default: + p.lit = "" + } + if debug { + fmt.Printf("%s: %q -> %q\n", scanner.TokenString(p.tok), p.scanner.TokenText(), p.lit) + } +} + +func declTypeName(pkg *types.Package, name string) *types.TypeName { + scope := pkg.Scope() + if obj := scope.Lookup(name); obj != nil { + return obj.(*types.TypeName) + } + obj := types.NewTypeName(token.NoPos, pkg, name, nil) + // a named type may be referred to before the underlying type + // is known - set it up + types.NewNamed(obj, nil, nil) + scope.Insert(obj) + return obj +} + +// ---------------------------------------------------------------------------- +// Error handling + +// Internal errors are boxed as importErrors. +type importError struct { + pos scanner.Position + err error +} + +func (e importError) Error() string { + return fmt.Sprintf("import error %s (byte offset = %d): %s", e.pos, e.pos.Offset, e.err) +} + +func (p *parser) error(err interface{}) { + if s, ok := err.(string); ok { + err = errors.New(s) + } + // panic with a runtime.Error if err is not an error + panic(importError{p.scanner.Pos(), err.(error)}) +} + +func (p *parser) errorf(format string, args ...interface{}) { + p.error(fmt.Sprintf(format, args...)) +} + +func (p *parser) expect(tok rune) string { + lit := p.lit + if p.tok != tok { + p.errorf("expected %s, got %s (%s)", scanner.TokenString(tok), scanner.TokenString(p.tok), lit) + } + p.next() + return lit +} + +func (p *parser) expectSpecial(tok string) { + sep := 'x' // not white space + i := 0 + for i < len(tok) && p.tok == rune(tok[i]) && sep > ' ' { + sep = p.scanner.Peek() // if sep <= ' ', there is white space before the next token + p.next() + i++ + } + if i < len(tok) { + p.errorf("expected %q, got %q", tok, tok[0:i]) + } +} + +func (p *parser) expectKeyword(keyword string) { + lit := p.expect(scanner.Ident) + if lit != keyword { + p.errorf("expected keyword %s, got %q", keyword, lit) + } +} + +// ---------------------------------------------------------------------------- +// Qualified and unqualified names + +// PackageId = string_lit . +// +func (p *parser) parsePackageId() string { + id, err := strconv.Unquote(p.expect(scanner.String)) + if err != nil { + p.error(err) + } + // id == "" stands for the imported package id + // (only known at time of package installation) + if id == "" { + id = p.id + } + return id +} + +// PackageName = ident . +// +func (p *parser) parsePackageName() string { + return p.expect(scanner.Ident) +} + +// dotIdentifier = ( ident | '·' ) { ident | int | '·' } . +func (p *parser) parseDotIdent() string { + ident := "" + if p.tok != scanner.Int { + sep := 'x' // not white space + for (p.tok == scanner.Ident || p.tok == scanner.Int || p.tok == '·') && sep > ' ' { + ident += p.lit + sep = p.scanner.Peek() // if sep <= ' ', there is white space before the next token + p.next() + } + } + if ident == "" { + p.expect(scanner.Ident) // use expect() for error handling + } + return ident +} + +// QualifiedName = "@" PackageId "." ( "?" | dotIdentifier ) . +// +func (p *parser) parseQualifiedName() (id, name string) { + p.expect('@') + id = p.parsePackageId() + p.expect('.') + // Per rev f280b8a485fd (10/2/2013), qualified names may be used for anonymous fields. + if p.tok == '?' { + p.next() + } else { + name = p.parseDotIdent() + } + return +} + +// getPkg returns the package for a given id. If the package is +// not found, create the package and add it to the p.localPkgs +// and p.sharedPkgs maps. name is the (expected) name of the +// package. If name == "", the package name is expected to be +// set later via an import clause in the export data. +// +// id identifies a package, usually by a canonical package path like +// "encoding/json" but possibly by a non-canonical import path like +// "./json". +// +func (p *parser) getPkg(id, name string) *types.Package { + // package unsafe is not in the packages maps - handle explicitly + if id == "unsafe" { + return types.Unsafe + } + + pkg := p.localPkgs[id] + if pkg == nil { + // first import of id from this package + pkg = p.sharedPkgs[id] + if pkg == nil { + // first import of id by this importer; + // add (possibly unnamed) pkg to shared packages + pkg = types.NewPackage(id, name) + p.sharedPkgs[id] = pkg + } + // add (possibly unnamed) pkg to local packages + if p.localPkgs == nil { + p.localPkgs = make(map[string]*types.Package) + } + p.localPkgs[id] = pkg + } else if name != "" { + // package exists already and we have an expected package name; + // make sure names match or set package name if necessary + if pname := pkg.Name(); pname == "" { + pkg.SetName(name) + } else if pname != name { + p.errorf("%s package name mismatch: %s (given) vs %s (expected)", id, pname, name) + } + } + return pkg +} + +// parseExportedName is like parseQualifiedName, but +// the package id is resolved to an imported *types.Package. +// +func (p *parser) parseExportedName() (pkg *types.Package, name string) { + id, name := p.parseQualifiedName() + pkg = p.getPkg(id, "") + return +} + +// ---------------------------------------------------------------------------- +// Types + +// BasicType = identifier . +// +func (p *parser) parseBasicType() types.Type { + id := p.expect(scanner.Ident) + obj := types.Universe.Lookup(id) + if obj, ok := obj.(*types.TypeName); ok { + return obj.Type() + } + p.errorf("not a basic type: %s", id) + return nil +} + +// ArrayType = "[" int_lit "]" Type . +// +func (p *parser) parseArrayType(parent *types.Package) types.Type { + // "[" already consumed and lookahead known not to be "]" + lit := p.expect(scanner.Int) + p.expect(']') + elem := p.parseType(parent) + n, err := strconv.ParseInt(lit, 10, 64) + if err != nil { + p.error(err) + } + return types.NewArray(elem, n) +} + +// MapType = "map" "[" Type "]" Type . +// +func (p *parser) parseMapType(parent *types.Package) types.Type { + p.expectKeyword("map") + p.expect('[') + key := p.parseType(parent) + p.expect(']') + elem := p.parseType(parent) + return types.NewMap(key, elem) +} + +// Name = identifier | "?" | QualifiedName . +// +// For unqualified and anonymous names, the returned package is the parent +// package unless parent == nil, in which case the returned package is the +// package being imported. (The parent package is not nil if the the name +// is an unqualified struct field or interface method name belonging to a +// type declared in another package.) +// +// For qualified names, the returned package is nil (and not created if +// it doesn't exist yet) unless materializePkg is set (which creates an +// unnamed package with valid package path). In the latter case, a +// subsequent import clause is expected to provide a name for the package. +// +func (p *parser) parseName(parent *types.Package, materializePkg bool) (pkg *types.Package, name string) { + pkg = parent + if pkg == nil { + pkg = p.sharedPkgs[p.id] + } + switch p.tok { + case scanner.Ident: + name = p.lit + p.next() + case '?': + // anonymous + p.next() + case '@': + // exported name prefixed with package path + pkg = nil + var id string + id, name = p.parseQualifiedName() + if materializePkg { + pkg = p.getPkg(id, "") + } + default: + p.error("name expected") + } + return +} + +func deref(typ types.Type) types.Type { + if p, _ := typ.(*types.Pointer); p != nil { + return p.Elem() + } + return typ +} + +// Field = Name Type [ string_lit ] . +// +func (p *parser) parseField(parent *types.Package) (*types.Var, string) { + pkg, name := p.parseName(parent, true) + + if name == "_" { + // Blank fields should be package-qualified because they + // are unexported identifiers, but gc does not qualify them. + // Assuming that the ident belongs to the current package + // causes types to change during re-exporting, leading + // to spurious "can't assign A to B" errors from go/types. + // As a workaround, pretend all blank fields belong + // to the same unique dummy package. + const blankpkg = "<_>" + pkg = p.getPkg(blankpkg, blankpkg) + } + + typ := p.parseType(parent) + 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: + p.errorf("anonymous field expected") + } + anonymous = true + } + tag := "" + if p.tok == scanner.String { + s := p.expect(scanner.String) + var err error + tag, err = strconv.Unquote(s) + if err != nil { + p.errorf("invalid struct tag %s: %s", s, err) + } + } + return types.NewField(token.NoPos, pkg, name, typ, anonymous), tag +} + +// StructType = "struct" "{" [ FieldList ] "}" . +// FieldList = Field { ";" Field } . +// +func (p *parser) parseStructType(parent *types.Package) types.Type { + var fields []*types.Var + var tags []string + + p.expectKeyword("struct") + p.expect('{') + for i := 0; p.tok != '}' && p.tok != scanner.EOF; i++ { + if i > 0 { + p.expect(';') + } + fld, tag := p.parseField(parent) + if tag != "" && tags == nil { + tags = make([]string, i) + } + if tags != nil { + tags = append(tags, tag) + } + fields = append(fields, fld) + } + p.expect('}') + + return types.NewStruct(fields, tags) +} + +// Parameter = ( identifier | "?" ) [ "..." ] Type [ string_lit ] . +// +func (p *parser) parseParameter() (par *types.Var, isVariadic bool) { + _, name := p.parseName(nil, false) + // remove gc-specific parameter numbering + if i := strings.Index(name, "·"); i >= 0 { + name = name[:i] + } + if p.tok == '.' { + p.expectSpecial("...") + isVariadic = true + } + typ := p.parseType(nil) + if isVariadic { + typ = types.NewSlice(typ) + } + // ignore argument tag (e.g. "noescape") + if p.tok == scanner.String { + p.next() + } + // TODO(gri) should we provide a package? + par = types.NewVar(token.NoPos, nil, name, typ) + return +} + +// Parameters = "(" [ ParameterList ] ")" . +// ParameterList = { Parameter "," } Parameter . +// +func (p *parser) parseParameters() (list []*types.Var, isVariadic bool) { + p.expect('(') + for p.tok != ')' && p.tok != scanner.EOF { + if len(list) > 0 { + p.expect(',') + } + par, variadic := p.parseParameter() + list = append(list, par) + if variadic { + if isVariadic { + p.error("... not on final argument") + } + isVariadic = true + } + } + p.expect(')') + + return +} + +// Signature = Parameters [ Result ] . +// Result = Type | Parameters . +// +func (p *parser) parseSignature(recv *types.Var) *types.Signature { + params, isVariadic := p.parseParameters() + + // optional result type + var results []*types.Var + if p.tok == '(' { + var variadic bool + results, variadic = p.parseParameters() + if variadic { + p.error("... not permitted on result type") + } + } + + return types.NewSignature(recv, types.NewTuple(params...), types.NewTuple(results...), isVariadic) +} + +// InterfaceType = "interface" "{" [ MethodList ] "}" . +// MethodList = Method { ";" Method } . +// Method = Name Signature . +// +// The methods of embedded interfaces are always "inlined" +// by the compiler and thus embedded interfaces are never +// visible in the export data. +// +func (p *parser) parseInterfaceType(parent *types.Package) types.Type { + var methods []*types.Func + + p.expectKeyword("interface") + p.expect('{') + for i := 0; p.tok != '}' && p.tok != scanner.EOF; i++ { + if i > 0 { + p.expect(';') + } + pkg, name := p.parseName(parent, true) + sig := p.parseSignature(nil) + methods = append(methods, types.NewFunc(token.NoPos, pkg, name, sig)) + } + p.expect('}') + + // Complete requires the type's embedded interfaces to be fully defined, + // but we do not define any + return types.NewInterface(methods, nil).Complete() +} + +// ChanType = ( "chan" [ "<-" ] | "<-" "chan" ) Type . +// +func (p *parser) parseChanType(parent *types.Package) types.Type { + dir := types.SendRecv + if p.tok == scanner.Ident { + p.expectKeyword("chan") + if p.tok == '<' { + p.expectSpecial("<-") + dir = types.SendOnly + } + } else { + p.expectSpecial("<-") + p.expectKeyword("chan") + dir = types.RecvOnly + } + elem := p.parseType(parent) + return types.NewChan(dir, elem) +} + +// Type = +// BasicType | TypeName | ArrayType | SliceType | StructType | +// PointerType | FuncType | InterfaceType | MapType | ChanType | +// "(" Type ")" . +// +// BasicType = ident . +// TypeName = ExportedName . +// SliceType = "[" "]" Type . +// PointerType = "*" Type . +// FuncType = "func" Signature . +// +func (p *parser) parseType(parent *types.Package) types.Type { + switch p.tok { + case scanner.Ident: + switch p.lit { + default: + return p.parseBasicType() + case "struct": + return p.parseStructType(parent) + case "func": + // FuncType + p.next() + return p.parseSignature(nil) + case "interface": + return p.parseInterfaceType(parent) + case "map": + return p.parseMapType(parent) + case "chan": + return p.parseChanType(parent) + } + case '@': + // TypeName + pkg, name := p.parseExportedName() + return declTypeName(pkg, name).Type() + case '[': + p.next() // look ahead + if p.tok == ']' { + // SliceType + p.next() + return types.NewSlice(p.parseType(parent)) + } + return p.parseArrayType(parent) + case '*': + // PointerType + p.next() + return types.NewPointer(p.parseType(parent)) + case '<': + return p.parseChanType(parent) + case '(': + // "(" Type ")" + p.next() + typ := p.parseType(parent) + p.expect(')') + return typ + } + p.errorf("expected type, got %s (%q)", scanner.TokenString(p.tok), p.lit) + return nil +} + +// ---------------------------------------------------------------------------- +// Declarations + +// ImportDecl = "import" PackageName PackageId . +// +func (p *parser) parseImportDecl() { + p.expectKeyword("import") + name := p.parsePackageName() + p.getPkg(p.parsePackageId(), name) +} + +// int_lit = [ "+" | "-" ] { "0" ... "9" } . +// +func (p *parser) parseInt() string { + s := "" + switch p.tok { + case '-': + s = "-" + p.next() + case '+': + p.next() + } + return s + p.expect(scanner.Int) +} + +// number = int_lit [ "p" int_lit ] . +// +func (p *parser) parseNumber() (typ *types.Basic, val exact.Value) { + // mantissa + mant := exact.MakeFromLiteral(p.parseInt(), token.INT, 0) + if mant == nil { + panic("invalid mantissa") + } + + if p.lit == "p" { + // exponent (base 2) + p.next() + exp, err := strconv.ParseInt(p.parseInt(), 10, 0) + if err != nil { + p.error(err) + } + if exp < 0 { + denom := exact.MakeInt64(1) + denom = exact.Shift(denom, token.SHL, uint(-exp)) + typ = types.Typ[types.UntypedFloat] + val = exact.BinaryOp(mant, token.QUO, denom) + return + } + if exp > 0 { + mant = exact.Shift(mant, token.SHL, uint(exp)) + } + typ = types.Typ[types.UntypedFloat] + val = mant + return + } + + typ = types.Typ[types.UntypedInt] + val = mant + return +} + +// ConstDecl = "const" ExportedName [ Type ] "=" Literal . +// Literal = bool_lit | int_lit | float_lit | complex_lit | rune_lit | string_lit . +// bool_lit = "true" | "false" . +// complex_lit = "(" float_lit "+" float_lit "i" ")" . +// rune_lit = "(" int_lit "+" int_lit ")" . +// string_lit = `"` { unicode_char } `"` . +// +func (p *parser) parseConstDecl() { + p.expectKeyword("const") + pkg, name := p.parseExportedName() + + var typ0 types.Type + if p.tok != '=' { + // constant types are never structured - no need for parent type + typ0 = p.parseType(nil) + } + + p.expect('=') + var typ types.Type + var val exact.Value + switch p.tok { + case scanner.Ident: + // bool_lit + if p.lit != "true" && p.lit != "false" { + p.error("expected true or false") + } + typ = types.Typ[types.UntypedBool] + val = exact.MakeBool(p.lit == "true") + p.next() + + case '-', scanner.Int: + // int_lit + typ, val = p.parseNumber() + + case '(': + // complex_lit or rune_lit + p.next() + if p.tok == scanner.Char { + p.next() + p.expect('+') + typ = types.Typ[types.UntypedRune] + _, val = p.parseNumber() + p.expect(')') + break + } + _, re := p.parseNumber() + p.expect('+') + _, im := p.parseNumber() + p.expectKeyword("i") + p.expect(')') + typ = types.Typ[types.UntypedComplex] + val = exact.BinaryOp(re, token.ADD, exact.MakeImag(im)) + + case scanner.Char: + // rune_lit + typ = types.Typ[types.UntypedRune] + val = exact.MakeFromLiteral(p.lit, token.CHAR, 0) + p.next() + + case scanner.String: + // string_lit + typ = types.Typ[types.UntypedString] + val = exact.MakeFromLiteral(p.lit, token.STRING, 0) + p.next() + + default: + p.errorf("expected literal got %s", scanner.TokenString(p.tok)) + } + + if typ0 == nil { + typ0 = typ + } + + pkg.Scope().Insert(types.NewConst(token.NoPos, pkg, name, typ0, val)) +} + +// TypeDecl = "type" ExportedName Type . +// +func (p *parser) parseTypeDecl() { + p.expectKeyword("type") + pkg, name := p.parseExportedName() + obj := declTypeName(pkg, name) + + // The type object may have been imported before and thus already + // have a type associated with it. We still need to parse the type + // structure, but throw it away if the object already has a type. + // This ensures that all imports refer to the same type object for + // a given type declaration. + typ := p.parseType(pkg) + + if name := obj.Type().(*types.Named); name.Underlying() == nil { + name.SetUnderlying(typ) + } +} + +// VarDecl = "var" ExportedName Type . +// +func (p *parser) parseVarDecl() { + p.expectKeyword("var") + pkg, name := p.parseExportedName() + typ := p.parseType(pkg) + pkg.Scope().Insert(types.NewVar(token.NoPos, pkg, name, typ)) +} + +// Func = Signature [ Body ] . +// Body = "{" ... "}" . +// +func (p *parser) parseFunc(recv *types.Var) *types.Signature { + sig := p.parseSignature(recv) + if p.tok == '{' { + p.next() + for i := 1; i > 0; p.next() { + switch p.tok { + case '{': + i++ + case '}': + i-- + } + } + } + return sig +} + +// MethodDecl = "func" Receiver Name Func . +// Receiver = "(" ( identifier | "?" ) [ "*" ] ExportedName ")" . +// +func (p *parser) parseMethodDecl() { + // "func" already consumed + p.expect('(') + recv, _ := p.parseParameter() // receiver + p.expect(')') + + // determine receiver base type object + base := deref(recv.Type()).(*types.Named) + + // parse method name, signature, and possibly inlined body + _, name := p.parseName(nil, false) + sig := p.parseFunc(recv) + + // methods always belong to the same package as the base type object + pkg := base.Obj().Pkg() + + // add method to type unless type was imported before + // and method exists already + // TODO(gri) This leads to a quadratic algorithm - ok for now because method counts are small. + base.AddMethod(types.NewFunc(token.NoPos, pkg, name, sig)) +} + +// FuncDecl = "func" ExportedName Func . +// +func (p *parser) parseFuncDecl() { + // "func" already consumed + pkg, name := p.parseExportedName() + typ := p.parseFunc(nil) + pkg.Scope().Insert(types.NewFunc(token.NoPos, pkg, name, typ)) +} + +// Decl = [ ImportDecl | ConstDecl | TypeDecl | VarDecl | FuncDecl | MethodDecl ] "\n" . +// +func (p *parser) parseDecl() { + if p.tok == scanner.Ident { + switch p.lit { + case "import": + p.parseImportDecl() + case "const": + p.parseConstDecl() + case "type": + p.parseTypeDecl() + case "var": + p.parseVarDecl() + case "func": + p.next() // look ahead + if p.tok == '(' { + p.parseMethodDecl() + } else { + p.parseFuncDecl() + } + } + } + p.expect('\n') +} + +// ---------------------------------------------------------------------------- +// Export + +// Export = "PackageClause { Decl } "$$" . +// PackageClause = "package" PackageName [ "safe" ] "\n" . +// +func (p *parser) parseExport() *types.Package { + p.expectKeyword("package") + name := p.parsePackageName() + if p.tok == scanner.Ident && p.lit == "safe" { + // package was compiled with -u option - ignore + p.next() + } + p.expect('\n') + + pkg := p.getPkg(p.id, name) + + for p.tok != '$' && p.tok != scanner.EOF { + p.parseDecl() + } + + if ch := p.scanner.Peek(); p.tok != '$' || ch != '$' { + // don't call next()/expect() since reading past the + // export data may cause scanner errors (e.g. NUL chars) + p.errorf("expected '$$', got %s %c", scanner.TokenString(p.tok), ch) + } + + if n := p.scanner.ErrorCount; n != 0 { + p.errorf("expected no scanner errors, got %d", n) + } + + // Record all locally referenced packages as imports. + var imports []*types.Package + for id, pkg2 := range p.localPkgs { + if pkg2.Name() == "" { + p.errorf("%s package has no name", id) + } + if id == p.id { + continue // avoid self-edge + } + imports = append(imports, pkg2) + } + sort.Sort(byPath(imports)) + pkg.SetImports(imports) + + // package was imported completely and without errors + pkg.MarkComplete() + + return pkg +} + +type byPath []*types.Package + +func (a byPath) Len() int { return len(a) } +func (a byPath) Swap(i, j int) { a[i], a[j] = a[j], a[i] } +func (a byPath) Less(i, j int) bool { return a[i].Path() < a[j].Path() } diff --git a/compiler/vendor/golang.org/x/tools/go/gcimporter15/isAlias18.go b/compiler/vendor/golang.org/x/tools/go/gcimporter15/isAlias18.go new file mode 100644 index 0000000..225ffee --- /dev/null +++ b/compiler/vendor/golang.org/x/tools/go/gcimporter15/isAlias18.go @@ -0,0 +1,13 @@ +// Copyright 2017 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. + +// +build !go1.9 + +package gcimporter + +import "go/types" + +func isAlias(obj *types.TypeName) bool { + return false // there are no type aliases before Go 1.9 +} diff --git a/compiler/vendor/golang.org/x/tools/go/gcimporter15/isAlias19.go b/compiler/vendor/golang.org/x/tools/go/gcimporter15/isAlias19.go new file mode 100644 index 0000000..c2025d8 --- /dev/null +++ b/compiler/vendor/golang.org/x/tools/go/gcimporter15/isAlias19.go @@ -0,0 +1,13 @@ +// Copyright 2017 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. + +// +build go1.9 + +package gcimporter + +import "go/types" + +func isAlias(obj *types.TypeName) bool { + return obj.IsAlias() +}