--- /dev/null
+// 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 modified copy of $GOROOT/src/go/internal/gcimporter/gcimporter.go,
+// but it also contains the original source-based importer code for Go1.6.
+// Once we stop supporting 1.6, we can remove that code.
+
+// Package gcimporter provides various functions for reading
+// gc-generated object files that can be used to implement the
+// Importer interface defined by the Go 1.5 standard library package.
+package gcimporter
+
+import (
+ "bufio"
+ "fmt"
+ "go/build"
+ "go/token"
+ "go/types"
+ "io"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+ "strings"
+)
+
+var pkgExts = [...]string{".a", ".o"}
+
+// FindPkg returns the filename and unique package id for an import
+// path based on package information provided by build.Import (using
+// the build.Default build.Context). A relative srcDir is interpreted
+// relative to the current working directory.
+// If no file was found, an empty filename is returned.
+//
+func FindPkg(path, srcDir string) (filename, id string) {
+ if path == "" {
+ return
+ }
+
+ var noext string
+ switch {
+ default:
+ // "x" -> "$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 == "" {
+ id = path // make sure we have an id to print in error message
+ 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
+}
+
+// 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, lookup func(path string) (io.ReadCloser, error)) (pkg *types.Package, err error) {
+ var rc io.ReadCloser
+ var filename, id string
+ if lookup != nil {
+ // With custom lookup specified, assume that caller has
+ // converted path to a canonical import path for use in the map.
+ if path == "unsafe" {
+ return types.Unsafe, nil
+ }
+ id = path
+
+ // No need to re-import if the package was imported completely before.
+ if pkg = packages[id]; pkg != nil && pkg.Complete() {
+ return
+ }
+ f, err := lookup(path)
+ if err != nil {
+ return nil, err
+ }
+ rc = f
+ } else {
+ filename, id = FindPkg(path, srcDir)
+ if filename == "" {
+ if path == "unsafe" {
+ return types.Unsafe, nil
+ }
+ return nil, fmt.Errorf("can't find import: %q", id)
+ }
+
+ // 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 nil, err
+ }
+ defer func() {
+ if err != nil {
+ // add file name to error
+ err = fmt.Errorf("%s: %v", filename, err)
+ }
+ }()
+ rc = f
+ }
+ defer rc.Close()
+
+ var hdr string
+ buf := bufio.NewReader(rc)
+ if hdr, _, err = findExportData(buf); err != nil {
+ return
+ }
+
+ switch hdr {
+ case "$$B\n":
+ var data []byte
+ data, err = ioutil.ReadAll(buf)
+ if err != nil {
+ break
+ }
+
+ // TODO(gri): allow clients of go/importer to provide a FileSet.
+ // Or, define a new standard go/types/gcexportdata package.
+ fset := token.NewFileSet()
+
+ // The indexed export format starts with an 'i'.
+ if len(data) == 0 || data[0] != 'i' {
+ return nil, fmt.Errorf("unknown export data format %c", data[0])
+ }
+ _, pkg, err = IImportData(fset, packages, data[1:], id)
+
+ default:
+ err = fmt.Errorf("unknown export data header: %q", hdr)
+ }
+
+ return
+}
+
+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() }
projects / dotfiles / .git / blobdiff