blob: 9f28fd7e8364d090a5f70df8510f9eb9707bfacc [file] [log] [blame]
// 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.
// Package load loads packages.
package load
import (
"bytes"
"fmt"
"go/build"
"go/token"
"io/ioutil"
"os"
pathpkg "path"
"path/filepath"
"sort"
"strconv"
"strings"
"unicode"
"unicode/utf8"
"cmd/go/internal/base"
"cmd/go/internal/cfg"
"cmd/go/internal/modinfo"
"cmd/go/internal/search"
"cmd/go/internal/str"
)
var (
// module hooks; nil if module use is disabled
ModBinDir func() string // return effective bin directory
ModLookup func(parentPath, path string) (dir, realPath string, err error) // lookup effective meaning of import
ModPackageModuleInfo func(path string) *modinfo.ModulePublic // return module info for Package struct
ModImportPaths func(args []string) []string // expand import paths
ModPackageBuildInfo func(main string, deps []string) string // return module info to embed in binary
ModInfoProg func(info string) []byte // wrap module info in .go code for binary
ModImportFromFiles func([]string) // update go.mod to add modules for imports in these files
)
var IgnoreImports bool // control whether we ignore imports in packages
// A Package describes a single package found in a directory.
type Package struct {
PackagePublic // visible in 'go list'
Internal PackageInternal // for use inside go command only
}
type PackagePublic struct {
// Note: These fields are part of the go command's public API.
// See list.go. It is okay to add fields, but not to change or
// remove existing ones. Keep in sync with list.go
Dir string `json:",omitempty"` // directory containing package sources
ImportPath string `json:",omitempty"` // import path of package in dir
ImportComment string `json:",omitempty"` // path in import comment on package statement
Name string `json:",omitempty"` // package name
Doc string `json:",omitempty"` // package documentation string
Target string `json:",omitempty"` // installed target for this package (may be executable)
Shlib string `json:",omitempty"` // the shared library that contains this package (only set when -linkshared)
Goroot bool `json:",omitempty"` // is this package found in the Go root?
Standard bool `json:",omitempty"` // is this package part of the standard Go library?
Root string `json:",omitempty"` // Go root or Go path dir containing this package
ConflictDir string `json:",omitempty"` // Dir is hidden by this other directory
BinaryOnly bool `json:",omitempty"` // package cannot be recompiled
ForTest string `json:",omitempty"` // package is only for use in named test
DepOnly bool `json:",omitempty"` // package is only as a dependency, not explicitly listed
Export string `json:",omitempty"` // file containing export data (set by go list -export)
Module *modinfo.ModulePublic `json:",omitempty"` // info about package's module, if any
// Stale and StaleReason remain here *only* for the list command.
// They are only initialized in preparation for list execution.
// The regular build determines staleness on the fly during action execution.
Stale bool `json:",omitempty"` // would 'go install' do anything for this package?
StaleReason string `json:",omitempty"` // why is Stale true?
// Source files
// If you add to this list you MUST add to p.AllFiles (below) too.
// Otherwise file name security lists will not apply to any new additions.
GoFiles []string `json:",omitempty"` // .go source files (excluding CgoFiles, TestGoFiles, XTestGoFiles)
CgoFiles []string `json:",omitempty"` // .go sources files that import "C"
IgnoredGoFiles []string `json:",omitempty"` // .go sources ignored due to build constraints
CFiles []string `json:",omitempty"` // .c source files
CXXFiles []string `json:",omitempty"` // .cc, .cpp and .cxx source files
MFiles []string `json:",omitempty"` // .m source files
HFiles []string `json:",omitempty"` // .h, .hh, .hpp and .hxx source files
FFiles []string `json:",omitempty"` // .f, .F, .for and .f90 Fortran source files
SFiles []string `json:",omitempty"` // .s source files
SwigFiles []string `json:",omitempty"` // .swig files
SwigCXXFiles []string `json:",omitempty"` // .swigcxx files
SysoFiles []string `json:",omitempty"` // .syso system object files added to package
// Cgo directives
CgoCFLAGS []string `json:",omitempty"` // cgo: flags for C compiler
CgoCPPFLAGS []string `json:",omitempty"` // cgo: flags for C preprocessor
CgoCXXFLAGS []string `json:",omitempty"` // cgo: flags for C++ compiler
CgoFFLAGS []string `json:",omitempty"` // cgo: flags for Fortran compiler
CgoLDFLAGS []string `json:",omitempty"` // cgo: flags for linker
CgoPkgConfig []string `json:",omitempty"` // cgo: pkg-config names
// Dependency information
Imports []string `json:",omitempty"` // import paths used by this package
Deps []string `json:",omitempty"` // all (recursively) imported dependencies
// Error information
Incomplete bool `json:",omitempty"` // was there an error loading this package or dependencies?
Error *PackageError `json:",omitempty"` // error loading this package (not dependencies)
DepsErrors []*PackageError `json:",omitempty"` // errors loading dependencies
// Test information
// If you add to this list you MUST add to p.AllFiles (below) too.
// Otherwise file name security lists will not apply to any new additions.
TestGoFiles []string `json:",omitempty"` // _test.go files in package
TestImports []string `json:",omitempty"` // imports from TestGoFiles
XTestGoFiles []string `json:",omitempty"` // _test.go files outside package
XTestImports []string `json:",omitempty"` // imports from XTestGoFiles
}
// AllFiles returns the names of all the files considered for the package.
// This is used for sanity and security checks, so we include all files,
// even IgnoredGoFiles, because some subcommands consider them.
// The go/build package filtered others out (like foo_wrongGOARCH.s)
// and that's OK.
func (p *Package) AllFiles() []string {
return str.StringList(
p.GoFiles,
p.CgoFiles,
p.IgnoredGoFiles,
p.CFiles,
p.CXXFiles,
p.MFiles,
p.HFiles,
p.FFiles,
p.SFiles,
p.SwigFiles,
p.SwigCXXFiles,
p.SysoFiles,
p.TestGoFiles,
p.XTestGoFiles,
)
}
// Desc returns the package "description", for use in b.showOutput.
func (p *Package) Desc() string {
if p.ForTest != "" {
return p.ImportPath + " [" + p.ForTest + ".test]"
}
return p.ImportPath
}
type PackageInternal struct {
// Unexported fields are not part of the public API.
Build *build.Package
Imports []*Package // this package's direct imports
RawImports []string // this package's original imports as they appear in the text of the program
ForceLibrary bool // this package is a library (even if named "main")
CmdlineFiles bool // package built from files listed on command line
CmdlinePkg bool // package listed on command line
CmdlinePkgLiteral bool // package listed as literal on command line (not via wildcard)
Local bool // imported via local path (./ or ../)
LocalPrefix string // interpret ./ and ../ imports relative to this prefix
ExeName string // desired name for temporary executable
CoverMode string // preprocess Go source files with the coverage tool in this mode
CoverVars map[string]*CoverVar // variables created by coverage analysis
OmitDebug bool // tell linker not to write debug information
GobinSubdir bool // install target would be subdir of GOBIN
BuildInfo string // add this info to package main
TestmainGo *[]byte // content for _testmain.go
Asmflags []string // -asmflags for this package
Gcflags []string // -gcflags for this package
Ldflags []string // -ldflags for this package
Gccgoflags []string // -gccgoflags for this package
}
type NoGoError struct {
Package *Package
}
func (e *NoGoError) Error() string {
// Count files beginning with _ and ., which we will pretend don't exist at all.
dummy := 0
for _, name := range e.Package.IgnoredGoFiles {
if strings.HasPrefix(name, "_") || strings.HasPrefix(name, ".") {
dummy++
}
}
if len(e.Package.IgnoredGoFiles) > dummy {
// Go files exist, but they were ignored due to build constraints.
return "build constraints exclude all Go files in " + e.Package.Dir
}
if len(e.Package.TestGoFiles)+len(e.Package.XTestGoFiles) > 0 {
// Test Go files exist, but we're not interested in them.
// The double-negative is unfortunate but we want e.Package.Dir
// to appear at the end of error message.
return "no non-test Go files in " + e.Package.Dir
}
return "no Go files in " + e.Package.Dir
}
// Resolve returns the resolved version of imports,
// which should be p.TestImports or p.XTestImports, NOT p.Imports.
// The imports in p.TestImports and p.XTestImports are not recursively
// loaded during the initial load of p, so they list the imports found in
// the source file, but most processing should be over the vendor-resolved
// import paths. We do this resolution lazily both to avoid file system work
// and because the eventual real load of the test imports (during 'go test')
// can produce better error messages if it starts with the original paths.
// The initial load of p loads all the non-test imports and rewrites
// the vendored paths, so nothing should ever call p.vendored(p.Imports).
func (p *Package) Resolve(imports []string) []string {
if len(imports) > 0 && len(p.Imports) > 0 && &imports[0] == &p.Imports[0] {
panic("internal error: p.Resolve(p.Imports) called")
}
seen := make(map[string]bool)
var all []string
for _, path := range imports {
path = ResolveImportPath(p, path)
if !seen[path] {
seen[path] = true
all = append(all, path)
}
}
sort.Strings(all)
return all
}
// CoverVar holds the name of the generated coverage variables targeting the named file.
type CoverVar struct {
File string // local file name
Var string // name of count struct
}
func (p *Package) copyBuild(pp *build.Package) {
p.Internal.Build = pp
if pp.PkgTargetRoot != "" && cfg.BuildPkgdir != "" {
old := pp.PkgTargetRoot
pp.PkgRoot = cfg.BuildPkgdir
pp.PkgTargetRoot = cfg.BuildPkgdir
pp.PkgObj = filepath.Join(cfg.BuildPkgdir, strings.TrimPrefix(pp.PkgObj, old))
}
p.Dir = pp.Dir
p.ImportPath = pp.ImportPath
p.ImportComment = pp.ImportComment
p.Name = pp.Name
p.Doc = pp.Doc
p.Root = pp.Root
p.ConflictDir = pp.ConflictDir
p.BinaryOnly = pp.BinaryOnly
// TODO? Target
p.Goroot = pp.Goroot
p.Standard = p.Goroot && p.ImportPath != "" && search.IsStandardImportPath(p.ImportPath)
p.GoFiles = pp.GoFiles
p.CgoFiles = pp.CgoFiles
p.IgnoredGoFiles = pp.IgnoredGoFiles
p.CFiles = pp.CFiles
p.CXXFiles = pp.CXXFiles
p.MFiles = pp.MFiles
p.HFiles = pp.HFiles
p.FFiles = pp.FFiles
p.SFiles = pp.SFiles
p.SwigFiles = pp.SwigFiles
p.SwigCXXFiles = pp.SwigCXXFiles
p.SysoFiles = pp.SysoFiles
p.CgoCFLAGS = pp.CgoCFLAGS
p.CgoCPPFLAGS = pp.CgoCPPFLAGS
p.CgoCXXFLAGS = pp.CgoCXXFLAGS
p.CgoFFLAGS = pp.CgoFFLAGS
p.CgoLDFLAGS = pp.CgoLDFLAGS
p.CgoPkgConfig = pp.CgoPkgConfig
// We modify p.Imports in place, so make copy now.
p.Imports = make([]string, len(pp.Imports))
copy(p.Imports, pp.Imports)
p.Internal.RawImports = pp.Imports
p.TestGoFiles = pp.TestGoFiles
p.TestImports = pp.TestImports
p.XTestGoFiles = pp.XTestGoFiles
p.XTestImports = pp.XTestImports
if IgnoreImports {
p.Imports = nil
p.TestImports = nil
p.XTestImports = nil
}
}
// A PackageError describes an error loading information about a package.
type PackageError struct {
ImportStack []string // shortest path from package named on command line to this one
Pos string // position of error
Err string // the error itself
IsImportCycle bool `json:"-"` // the error is an import cycle
Hard bool `json:"-"` // whether the error is soft or hard; soft errors are ignored in some places
}
func (p *PackageError) Error() string {
// Import cycles deserve special treatment.
if p.IsImportCycle {
return fmt.Sprintf("%s\npackage %s\n", p.Err, strings.Join(p.ImportStack, "\n\timports "))
}
if p.Pos != "" {
// Omit import stack. The full path to the file where the error
// is the most important thing.
return p.Pos + ": " + p.Err
}
if len(p.ImportStack) == 0 {
return p.Err
}
return "package " + strings.Join(p.ImportStack, "\n\timports ") + ": " + p.Err
}
// An ImportStack is a stack of import paths.
type ImportStack []string
func (s *ImportStack) Push(p string) {
*s = append(*s, p)
}
func (s *ImportStack) Pop() {
*s = (*s)[0 : len(*s)-1]
}
func (s *ImportStack) Copy() []string {
return append([]string{}, *s...)
}
// shorterThan reports whether sp is shorter than t.
// We use this to record the shortest import sequence
// that leads to a particular package.
func (sp *ImportStack) shorterThan(t []string) bool {
s := *sp
if len(s) != len(t) {
return len(s) < len(t)
}
// If they are the same length, settle ties using string ordering.
for i := range s {
if s[i] != t[i] {
return s[i] < t[i]
}
}
return false // they are equal
}
// packageCache is a lookup cache for loadPackage,
// so that if we look up a package multiple times
// we return the same pointer each time.
var packageCache = map[string]*Package{}
func ClearPackageCache() {
for name := range packageCache {
delete(packageCache, name)
}
}
func ClearPackageCachePartial(args []string) {
for _, arg := range args {
p := packageCache[arg]
if p != nil {
delete(packageCache, p.Dir)
delete(packageCache, p.ImportPath)
}
}
}
// reloadPackage is like loadPackage but makes sure
// not to use the package cache.
func ReloadPackage(arg string, stk *ImportStack) *Package {
p := packageCache[arg]
if p != nil {
delete(packageCache, p.Dir)
delete(packageCache, p.ImportPath)
}
return LoadPackage(arg, stk)
}
// dirToImportPath returns the pseudo-import path we use for a package
// outside the Go path. It begins with _/ and then contains the full path
// to the directory. If the package lives in c:\home\gopher\my\pkg then
// the pseudo-import path is _/c_/home/gopher/my/pkg.
// Using a pseudo-import path like this makes the ./ imports no longer
// a special case, so that all the code to deal with ordinary imports works
// automatically.
func dirToImportPath(dir string) string {
return pathpkg.Join("_", strings.Map(makeImportValid, filepath.ToSlash(dir)))
}
func makeImportValid(r rune) rune {
// Should match Go spec, compilers, and ../../go/parser/parser.go:/isValidImport.
const illegalChars = `!"#$%&'()*,:;<=>?[\]^{|}` + "`\uFFFD"
if !unicode.IsGraphic(r) || unicode.IsSpace(r) || strings.ContainsRune(illegalChars, r) {
return '_'
}
return r
}
// Mode flags for loadImport and download (in get.go).
const (
// ResolveImport means that loadImport should do import path expansion.
// That is, ResolveImport means that the import path came from
// a source file and has not been expanded yet to account for
// vendoring or possible module adjustment.
// Every import path should be loaded initially with ResolveImport,
// and then the expanded version (for example with the /vendor/ in it)
// gets recorded as the canonical import path. At that point, future loads
// of that package must not pass ResolveImport, because
// disallowVendor will reject direct use of paths containing /vendor/.
ResolveImport = 1 << iota
// ResolveModule is for download (part of "go get") and indicates
// that the module adjustment should be done, but not vendor adjustment.
ResolveModule
// GetTestDeps is for download (part of "go get") and indicates
// that test dependencies should be fetched too.
GetTestDeps
)
// LoadImport scans the directory named by path, which must be an import path,
// but possibly a local import path (an absolute file system path or one beginning
// with ./ or ../). A local relative path is interpreted relative to srcDir.
// It returns a *Package describing the package found in that directory.
func LoadImport(path, srcDir string, parent *Package, stk *ImportStack, importPos []token.Position, mode int) *Package {
stk.Push(path)
defer stk.Pop()
if strings.HasPrefix(path, "mod/") {
// Paths beginning with "mod/" might accidentally
// look in the module cache directory tree in $GOPATH/src/mod/.
// This prefix is owned by the Go core for possible use in the
// standard library (since it does not begin with a domain name),
// so it's OK to disallow entirely.
return &Package{
PackagePublic: PackagePublic{
ImportPath: path,
Error: &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("disallowed import path %q", path),
},
},
}
}
if strings.Contains(path, "@") {
var text string
if cfg.ModulesEnabled {
text = "can only use path@version syntax with 'go get'"
} else {
text = "cannot use path@version syntax in GOPATH mode"
}
return &Package{
PackagePublic: PackagePublic{
ImportPath: path,
Error: &PackageError{
ImportStack: stk.Copy(),
Err: text,
},
},
}
}
// Determine canonical identifier for this package.
// For a local import the identifier is the pseudo-import path
// we create from the full directory to the package.
// Otherwise it is the usual import path.
// For vendored imports, it is the expanded form.
importPath := path
origPath := path
isLocal := build.IsLocalImport(path)
var modDir string
var modErr error
if isLocal {
importPath = dirToImportPath(filepath.Join(srcDir, path))
} else if cfg.ModulesEnabled {
parentPath := ""
if parent != nil {
parentPath = parent.ImportPath
}
var p string
modDir, p, modErr = ModLookup(parentPath, path)
if modErr == nil {
importPath = p
}
} else if mode&ResolveImport != 0 {
// We do our own path resolution, because we want to
// find out the key to use in packageCache without the
// overhead of repeated calls to buildContext.Import.
// The code is also needed in a few other places anyway.
path = ResolveImportPath(parent, path)
importPath = path
} else if mode&ResolveModule != 0 {
path = ModuleImportPath(parent, path)
importPath = path
}
p := packageCache[importPath]
if p != nil {
p = reusePackage(p, stk)
} else {
p = new(Package)
p.Internal.Local = isLocal
p.ImportPath = importPath
packageCache[importPath] = p
// Load package.
// Import always returns bp != nil, even if an error occurs,
// in order to return partial information.
var bp *build.Package
var err error
if modDir != "" {
bp, err = cfg.BuildContext.ImportDir(modDir, 0)
} else if modErr != nil {
bp = new(build.Package)
err = fmt.Errorf("unknown import path %q: %v", importPath, modErr)
} else if cfg.ModulesEnabled && path != "unsafe" {
bp = new(build.Package)
err = fmt.Errorf("unknown import path %q: internal error: module loader did not resolve import", importPath)
} else {
buildMode := build.ImportComment
if mode&ResolveImport == 0 || path != origPath {
// Not vendoring, or we already found the vendored path.
buildMode |= build.IgnoreVendor
}
bp, err = cfg.BuildContext.Import(path, srcDir, buildMode)
}
bp.ImportPath = importPath
if cfg.GOBIN != "" {
bp.BinDir = cfg.GOBIN
} else if cfg.ModulesEnabled {
bp.BinDir = ModBinDir()
}
if modDir == "" && err == nil && !isLocal && bp.ImportComment != "" && bp.ImportComment != path &&
!strings.Contains(path, "/vendor/") && !strings.HasPrefix(path, "vendor/") {
err = fmt.Errorf("code in directory %s expects import %q", bp.Dir, bp.ImportComment)
}
p.load(stk, bp, err)
if p.Error != nil && p.Error.Pos == "" {
p = setErrorPos(p, importPos)
}
if modDir == "" && origPath != cleanImport(origPath) {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("non-canonical import path: %q should be %q", origPath, pathpkg.Clean(origPath)),
}
p.Incomplete = true
}
}
// Checked on every import because the rules depend on the code doing the importing.
if perr := disallowInternal(srcDir, p, stk); perr != p {
return setErrorPos(perr, importPos)
}
if mode&ResolveImport != 0 {
if perr := disallowVendor(srcDir, origPath, p, stk); perr != p {
return setErrorPos(perr, importPos)
}
}
if p.Name == "main" && parent != nil && parent.Dir != p.Dir {
perr := *p
perr.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("import %q is a program, not an importable package", path),
}
return setErrorPos(&perr, importPos)
}
if p.Internal.Local && parent != nil && !parent.Internal.Local {
perr := *p
perr.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("local import %q in non-local package", path),
}
return setErrorPos(&perr, importPos)
}
return p
}
func setErrorPos(p *Package, importPos []token.Position) *Package {
if len(importPos) > 0 {
pos := importPos[0]
pos.Filename = base.ShortPath(pos.Filename)
p.Error.Pos = pos.String()
}
return p
}
func cleanImport(path string) string {
orig := path
path = pathpkg.Clean(path)
if strings.HasPrefix(orig, "./") && path != ".." && !strings.HasPrefix(path, "../") {
path = "./" + path
}
return path
}
var isDirCache = map[string]bool{}
func isDir(path string) bool {
result, ok := isDirCache[path]
if ok {
return result
}
fi, err := os.Stat(path)
result = err == nil && fi.IsDir()
isDirCache[path] = result
return result
}
// ResolveImportPath returns the true meaning of path when it appears in parent.
// There are two different resolutions applied.
// First, there is Go 1.5 vendoring (golang.org/s/go15vendor).
// If vendor expansion doesn't trigger, then the path is also subject to
// Go 1.11 module legacy conversion (golang.org/issue/25069).
func ResolveImportPath(parent *Package, path string) (found string) {
if cfg.ModulesEnabled {
parentPath := ""
if parent != nil {
parentPath = parent.ImportPath
}
if _, p, e := ModLookup(parentPath, path); e == nil {
return p
}
return path
}
found = VendoredImportPath(parent, path)
if found != path {
return found
}
return ModuleImportPath(parent, path)
}
// dirAndRoot returns the source directory and workspace root
// for the package p, guaranteeing that root is a path prefix of dir.
func dirAndRoot(p *Package) (dir, root string) {
dir = filepath.Clean(p.Dir)
root = filepath.Join(p.Root, "src")
if !str.HasFilePathPrefix(dir, root) || p.ImportPath != "command-line-arguments" && filepath.Join(root, p.ImportPath) != dir {
// Look for symlinks before reporting error.
dir = expandPath(dir)
root = expandPath(root)
}
if !str.HasFilePathPrefix(dir, root) || len(dir) <= len(root) || dir[len(root)] != filepath.Separator || p.ImportPath != "command-line-arguments" && !p.Internal.Local && filepath.Join(root, p.ImportPath) != dir {
base.Fatalf("unexpected directory layout:\n"+
" import path: %s\n"+
" root: %s\n"+
" dir: %s\n"+
" expand root: %s\n"+
" expand dir: %s\n"+
" separator: %s",
p.ImportPath,
filepath.Join(p.Root, "src"),
filepath.Clean(p.Dir),
root,
dir,
string(filepath.Separator))
}
return dir, root
}
// VendoredImportPath returns the vendor-expansion of path when it appears in parent.
// If parent is x/y/z, then path might expand to x/y/z/vendor/path, x/y/vendor/path,
// x/vendor/path, vendor/path, or else stay path if none of those exist.
// VendoredImportPath returns the expanded path or, if no expansion is found, the original.
func VendoredImportPath(parent *Package, path string) (found string) {
if parent == nil || parent.Root == "" {
return path
}
dir, root := dirAndRoot(parent)
vpath := "vendor/" + path
for i := len(dir); i >= len(root); i-- {
if i < len(dir) && dir[i] != filepath.Separator {
continue
}
// Note: checking for the vendor directory before checking
// for the vendor/path directory helps us hit the
// isDir cache more often. It also helps us prepare a more useful
// list of places we looked, to report when an import is not found.
if !isDir(filepath.Join(dir[:i], "vendor")) {
continue
}
targ := filepath.Join(dir[:i], vpath)
if isDir(targ) && hasGoFiles(targ) {
importPath := parent.ImportPath
if importPath == "command-line-arguments" {
// If parent.ImportPath is 'command-line-arguments'.
// set to relative directory to root (also chopped root directory)
importPath = dir[len(root)+1:]
}
// We started with parent's dir c:\gopath\src\foo\bar\baz\quux\xyzzy.
// We know the import path for parent's dir.
// We chopped off some number of path elements and
// added vendor\path to produce c:\gopath\src\foo\bar\baz\vendor\path.
// Now we want to know the import path for that directory.
// Construct it by chopping the same number of path elements
// (actually the same number of bytes) from parent's import path
// and then append /vendor/path.
chopped := len(dir) - i
if chopped == len(importPath)+1 {
// We walked up from c:\gopath\src\foo\bar
// and found c:\gopath\src\vendor\path.
// We chopped \foo\bar (length 8) but the import path is "foo/bar" (length 7).
// Use "vendor/path" without any prefix.
return vpath
}
return importPath[:len(importPath)-chopped] + "/" + vpath
}
}
return path
}
var (
modulePrefix = []byte("\nmodule ")
goModPathCache = make(map[string]string)
)
// goModPath returns the module path in the go.mod in dir, if any.
func goModPath(dir string) (path string) {
path, ok := goModPathCache[dir]
if ok {
return path
}
defer func() {
goModPathCache[dir] = path
}()
data, err := ioutil.ReadFile(filepath.Join(dir, "go.mod"))
if err != nil {
return ""
}
var i int
if bytes.HasPrefix(data, modulePrefix[1:]) {
i = 0
} else {
i = bytes.Index(data, modulePrefix)
if i < 0 {
return ""
}
i++
}
line := data[i:]
// Cut line at \n, drop trailing \r if present.
if j := bytes.IndexByte(line, '\n'); j >= 0 {
line = line[:j]
}
if line[len(line)-1] == '\r' {
line = line[:len(line)-1]
}
line = line[len("module "):]
// If quoted, unquote.
path = strings.TrimSpace(string(line))
if path != "" && path[0] == '"' {
s, err := strconv.Unquote(path)
if err != nil {
return ""
}
path = s
}
return path
}
// findVersionElement returns the slice indices of the final version element /vN in path.
// If there is no such element, it returns -1, -1.
func findVersionElement(path string) (i, j int) {
j = len(path)
for i = len(path) - 1; i >= 0; i-- {
if path[i] == '/' {
if isVersionElement(path[i:j]) {
return i, j
}
j = i
}
}
return -1, -1
}
// isVersionElement reports whether s is a well-formed path version element:
// v2, v3, v10, etc, but not v0, v05, v1.
func isVersionElement(s string) bool {
if len(s) < 3 || s[0] != '/' || s[1] != 'v' || s[2] == '0' || s[2] == '1' && len(s) == 3 {
return false
}
for i := 2; i < len(s); i++ {
if s[i] < '0' || '9' < s[i] {
return false
}
}
return true
}
// ModuleImportPath translates import paths found in go modules
// back down to paths that can be resolved in ordinary builds.
//
// Define “new” code as code with a go.mod file in the same directory
// or a parent directory. If an import in new code says x/y/v2/z but
// x/y/v2/z does not exist and x/y/go.mod says “module x/y/v2”,
// then go build will read the import as x/y/z instead.
// See golang.org/issue/25069.
func ModuleImportPath(parent *Package, path string) (found string) {
if parent == nil || parent.Root == "" {
return path
}
// If there are no vN elements in path, leave it alone.
// (The code below would do the same, but only after
// some other file system accesses that we can avoid
// here by returning early.)
if i, _ := findVersionElement(path); i < 0 {
return path
}
dir, root := dirAndRoot(parent)
// Consider dir and parents, up to and including root.
for i := len(dir); i >= len(root); i-- {
if i < len(dir) && dir[i] != filepath.Separator {
continue
}
if goModPath(dir[:i]) != "" {
goto HaveGoMod
}
}
// This code is not in a tree with a go.mod,
// so apply no changes to the path.
return path
HaveGoMod:
// This import is in a tree with a go.mod.
// Allow it to refer to code in GOPATH/src/x/y/z as x/y/v2/z
// if GOPATH/src/x/y/go.mod says module "x/y/v2",
// If x/y/v2/z exists, use it unmodified.
if bp, _ := cfg.BuildContext.Import(path, "", build.IgnoreVendor); bp.Dir != "" {
return path
}
// Otherwise look for a go.mod supplying a version element.
// Some version-like elements may appear in paths but not
// be module versions; we skip over those to look for module
// versions. For example the module m/v2 might have a
// package m/v2/api/v1/foo.
limit := len(path)
for limit > 0 {
i, j := findVersionElement(path[:limit])
if i < 0 {
return path
}
if bp, _ := cfg.BuildContext.Import(path[:i], "", build.IgnoreVendor); bp.Dir != "" {
if mpath := goModPath(bp.Dir); mpath != "" {
// Found a valid go.mod file, so we're stopping the search.
// If the path is m/v2/p and we found m/go.mod that says
// "module m/v2", then we return "m/p".
if mpath == path[:j] {
return path[:i] + path[j:]
}
// Otherwise just return the original path.
// We didn't find anything worth rewriting,
// and the go.mod indicates that we should
// not consider parent directories.
return path
}
}
limit = i
}
return path
}
// hasGoFiles reports whether dir contains any files with names ending in .go.
// For a vendor check we must exclude directories that contain no .go files.
// Otherwise it is not possible to vendor just a/b/c and still import the
// non-vendored a/b. See golang.org/issue/13832.
func hasGoFiles(dir string) bool {
fis, _ := ioutil.ReadDir(dir)
for _, fi := range fis {
if !fi.IsDir() && strings.HasSuffix(fi.Name(), ".go") {
return true
}
}
return false
}
// reusePackage reuses package p to satisfy the import at the top
// of the import stack stk. If this use causes an import loop,
// reusePackage updates p's error information to record the loop.
func reusePackage(p *Package, stk *ImportStack) *Package {
// We use p.Internal.Imports==nil to detect a package that
// is in the midst of its own loadPackage call
// (all the recursion below happens before p.Internal.Imports gets set).
if p.Internal.Imports == nil {
if p.Error == nil {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: "import cycle not allowed",
IsImportCycle: true,
}
}
p.Incomplete = true
}
// Don't rewrite the import stack in the error if we have an import cycle.
// If we do, we'll lose the path that describes the cycle.
if p.Error != nil && !p.Error.IsImportCycle && stk.shorterThan(p.Error.ImportStack) {
p.Error.ImportStack = stk.Copy()
}
return p
}
// disallowInternal checks that srcDir is allowed to import p.
// If the import is allowed, disallowInternal returns the original package p.
// If not, it returns a new package containing just an appropriate error.
func disallowInternal(srcDir string, p *Package, stk *ImportStack) *Package {
// golang.org/s/go14internal:
// An import of a path containing the element “internal”
// is disallowed if the importing code is outside the tree
// rooted at the parent of the “internal” directory.
// There was an error loading the package; stop here.
if p.Error != nil {
return p
}
// The generated 'testmain' package is allowed to access testing/internal/...,
// as if it were generated into the testing directory tree
// (it's actually in a temporary directory outside any Go tree).
// This cleans up a former kludge in passing functionality to the testing package.
if strings.HasPrefix(p.ImportPath, "testing/internal") && len(*stk) >= 2 && (*stk)[len(*stk)-2] == "testmain" {
return p
}
// We can't check standard packages with gccgo.
if cfg.BuildContext.Compiler == "gccgo" && p.Standard {
return p
}
// The stack includes p.ImportPath.
// If that's the only thing on the stack, we started
// with a name given on the command line, not an
// import. Anything listed on the command line is fine.
if len(*stk) == 1 {
return p
}
// Check for "internal" element: three cases depending on begin of string and/or end of string.
i, ok := findInternal(p.ImportPath)
if !ok {
return p
}
// Internal is present.
// Map import path back to directory corresponding to parent of internal.
if i > 0 {
i-- // rewind over slash in ".../internal"
}
parent := p.Dir[:i+len(p.Dir)-len(p.ImportPath)]
if str.HasFilePathPrefix(filepath.Clean(srcDir), filepath.Clean(parent)) {
return p
}
// Look for symlinks before reporting error.
srcDir = expandPath(srcDir)
parent = expandPath(parent)
if str.HasFilePathPrefix(filepath.Clean(srcDir), filepath.Clean(parent)) {
return p
}
// Internal is present, and srcDir is outside parent's tree. Not allowed.
perr := *p
perr.Error = &PackageError{
ImportStack: stk.Copy(),
Err: "use of internal package " + p.ImportPath + " not allowed",
}
perr.Incomplete = true
return &perr
}
// findInternal looks for the final "internal" path element in the given import path.
// If there isn't one, findInternal returns ok=false.
// Otherwise, findInternal returns ok=true and the index of the "internal".
func findInternal(path string) (index int, ok bool) {
// Three cases, depending on internal at start/end of string or not.
// The order matters: we must return the index of the final element,
// because the final one produces the most restrictive requirement
// on the importer.
switch {
case strings.HasSuffix(path, "/internal"):
return len(path) - len("internal"), true
case strings.Contains(path, "/internal/"):
return strings.LastIndex(path, "/internal/") + 1, true
case path == "internal", strings.HasPrefix(path, "internal/"):
return 0, true
}
return 0, false
}
// disallowVendor checks that srcDir is allowed to import p as path.
// If the import is allowed, disallowVendor returns the original package p.
// If not, it returns a new package containing just an appropriate error.
func disallowVendor(srcDir, path string, p *Package, stk *ImportStack) *Package {
// The stack includes p.ImportPath.
// If that's the only thing on the stack, we started
// with a name given on the command line, not an
// import. Anything listed on the command line is fine.
if len(*stk) == 1 {
return p
}
if perr := disallowVendorVisibility(srcDir, p, stk); perr != p {
return perr
}
// Paths like x/vendor/y must be imported as y, never as x/vendor/y.
if i, ok := FindVendor(path); ok {
perr := *p
perr.Error = &PackageError{
ImportStack: stk.Copy(),
Err: "must be imported as " + path[i+len("vendor/"):],
}
perr.Incomplete = true
return &perr
}
return p
}
// disallowVendorVisibility checks that srcDir is allowed to import p.
// The rules are the same as for /internal/ except that a path ending in /vendor
// is not subject to the rules, only subdirectories of vendor.
// This allows people to have packages and commands named vendor,
// for maximal compatibility with existing source trees.
func disallowVendorVisibility(srcDir string, p *Package, stk *ImportStack) *Package {
// The stack includes p.ImportPath.
// If that's the only thing on the stack, we started
// with a name given on the command line, not an
// import. Anything listed on the command line is fine.
if len(*stk) == 1 {
return p
}
// Check for "vendor" element.
i, ok := FindVendor(p.ImportPath)
if !ok {
return p
}
// Vendor is present.
// Map import path back to directory corresponding to parent of vendor.
if i > 0 {
i-- // rewind over slash in ".../vendor"
}
truncateTo := i + len(p.Dir) - len(p.ImportPath)
if truncateTo < 0 || len(p.Dir) < truncateTo {
return p
}
parent := p.Dir[:truncateTo]
if str.HasFilePathPrefix(filepath.Clean(srcDir), filepath.Clean(parent)) {
return p
}
// Look for symlinks before reporting error.
srcDir = expandPath(srcDir)
parent = expandPath(parent)
if str.HasFilePathPrefix(filepath.Clean(srcDir), filepath.Clean(parent)) {
return p
}
// Vendor is present, and srcDir is outside parent's tree. Not allowed.
perr := *p
perr.Error = &PackageError{
ImportStack: stk.Copy(),
Err: "use of vendored package not allowed",
}
perr.Incomplete = true
return &perr
}
// FindVendor looks for the last non-terminating "vendor" path element in the given import path.
// If there isn't one, FindVendor returns ok=false.
// Otherwise, FindVendor returns ok=true and the index of the "vendor".
//
// Note that terminating "vendor" elements don't count: "x/vendor" is its own package,
// not the vendored copy of an import "" (the empty import path).
// This will allow people to have packages or commands named vendor.
// This may help reduce breakage, or it may just be confusing. We'll see.
func FindVendor(path string) (index int, ok bool) {
// Two cases, depending on internal at start of string or not.
// The order matters: we must return the index of the final element,
// because the final one is where the effective import path starts.
switch {
case strings.Contains(path, "/vendor/"):
return strings.LastIndex(path, "/vendor/") + 1, true
case strings.HasPrefix(path, "vendor/"):
return 0, true
}
return 0, false
}
type TargetDir int
const (
ToTool TargetDir = iota // to GOROOT/pkg/tool (default for cmd/*)
ToBin // to bin dir inside package root (default for non-cmd/*)
StalePath // an old import path; fail to build
)
// InstallTargetDir reports the target directory for installing the command p.
func InstallTargetDir(p *Package) TargetDir {
if strings.HasPrefix(p.ImportPath, "code.google.com/p/go.tools/cmd/") {
return StalePath
}
if p.Goroot && strings.HasPrefix(p.ImportPath, "cmd/") && p.Name == "main" {
switch p.ImportPath {
case "cmd/go", "cmd/gofmt":
return ToBin
}
return ToTool
}
return ToBin
}
var cgoExclude = map[string]bool{
"runtime/cgo": true,
}
var cgoSyscallExclude = map[string]bool{
"runtime/cgo": true,
"runtime/race": true,
"runtime/msan": true,
}
var foldPath = make(map[string]string)
// load populates p using information from bp, err, which should
// be the result of calling build.Context.Import.
func (p *Package) load(stk *ImportStack, bp *build.Package, err error) {
p.copyBuild(bp)
// Decide whether p was listed on the command line.
// Given that load is called while processing the command line,
// you might think we could simply pass a flag down into load
// saying whether we are loading something named on the command
// line or something to satisfy an import. But the first load of a
// package named on the command line may be as a dependency
// of an earlier package named on the command line, not when we
// get to that package during command line processing.
// For example "go test fmt reflect" will load reflect as a dependency
// of fmt before it attempts to load as a command-line argument.
// Because loads are cached, the later load will be a no-op,
// so it is important that the first load can fill in CmdlinePkg correctly.
// Hence the call to a separate matching check here.
p.Internal.CmdlinePkg = isCmdlinePkg(p)
p.Internal.CmdlinePkgLiteral = isCmdlinePkgLiteral(p)
p.Internal.Asmflags = BuildAsmflags.For(p)
p.Internal.Gcflags = BuildGcflags.For(p)
p.Internal.Ldflags = BuildLdflags.For(p)
p.Internal.Gccgoflags = BuildGccgoflags.For(p)
// The localPrefix is the path we interpret ./ imports relative to.
// Synthesized main packages sometimes override this.
if p.Internal.Local {
p.Internal.LocalPrefix = dirToImportPath(p.Dir)
}
if err != nil {
if _, ok := err.(*build.NoGoError); ok {
err = &NoGoError{Package: p}
}
p.Incomplete = true
err = base.ExpandScanner(err)
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: err.Error(),
}
return
}
useBindir := p.Name == "main"
if !p.Standard {
switch cfg.BuildBuildmode {
case "c-archive", "c-shared", "plugin":
useBindir = false
}
}
if useBindir {
// Report an error when the old code.google.com/p/go.tools paths are used.
if InstallTargetDir(p) == StalePath {
newPath := strings.Replace(p.ImportPath, "code.google.com/p/go.", "golang.org/x/", 1)
e := fmt.Sprintf("the %v command has moved; use %v instead.", p.ImportPath, newPath)
p.Error = &PackageError{Err: e}
return
}
_, elem := filepath.Split(p.Dir)
full := cfg.BuildContext.GOOS + "_" + cfg.BuildContext.GOARCH + "/" + elem
if cfg.BuildContext.GOOS != base.ToolGOOS || cfg.BuildContext.GOARCH != base.ToolGOARCH {
// Install cross-compiled binaries to subdirectories of bin.
elem = full
}
if p.Internal.Build.BinDir == "" && cfg.ModulesEnabled {
p.Internal.Build.BinDir = ModBinDir()
}
if p.Internal.Build.BinDir != "" {
// Install to GOBIN or bin of GOPATH entry.
p.Target = filepath.Join(p.Internal.Build.BinDir, elem)
if !p.Goroot && strings.Contains(elem, "/") && cfg.GOBIN != "" {
// Do not create $GOBIN/goos_goarch/elem.
p.Target = ""
p.Internal.GobinSubdir = true
}
}
if InstallTargetDir(p) == ToTool {
// This is for 'go tool'.
// Override all the usual logic and force it into the tool directory.
if cfg.BuildToolchainName == "gccgo" {
p.Target = filepath.Join(base.ToolDir, elem)
} else {
p.Target = filepath.Join(cfg.GOROOTpkg, "tool", full)
}
}
if p.Target != "" && cfg.BuildContext.GOOS == "windows" {
p.Target += ".exe"
}
} else if p.Internal.Local {
// Local import turned into absolute path.
// No permanent install target.
p.Target = ""
} else {
p.Target = p.Internal.Build.PkgObj
if cfg.BuildLinkshared {
shlibnamefile := p.Target[:len(p.Target)-2] + ".shlibname"
shlib, err := ioutil.ReadFile(shlibnamefile)
if err != nil && !os.IsNotExist(err) {
base.Fatalf("reading shlibname: %v", err)
}
if err == nil {
libname := strings.TrimSpace(string(shlib))
if cfg.BuildContext.Compiler == "gccgo" {
p.Shlib = filepath.Join(p.Internal.Build.PkgTargetRoot, "shlibs", libname)
} else {
p.Shlib = filepath.Join(p.Internal.Build.PkgTargetRoot, libname)
}
}
}
}
// Build augmented import list to add implicit dependencies.
// Be careful not to add imports twice, just to avoid confusion.
importPaths := p.Imports
addImport := func(path string) {
for _, p := range importPaths {
if path == p {
return
}
}
importPaths = append(importPaths, path)
}
// Cgo translation adds imports of "runtime/cgo" and "syscall",
// except for certain packages, to avoid circular dependencies.
if p.UsesCgo() && (!p.Standard || !cgoExclude[p.ImportPath]) && cfg.BuildContext.Compiler != "gccgo" {
addImport("runtime/cgo")
}
if p.UsesCgo() && (!p.Standard || !cgoSyscallExclude[p.ImportPath]) {
addImport("syscall")
}
// SWIG adds imports of some standard packages.
if p.UsesSwig() {
if cfg.BuildContext.Compiler != "gccgo" {
addImport("runtime/cgo")
}
addImport("syscall")
addImport("sync")
// TODO: The .swig and .swigcxx files can use
// %go_import directives to import other packages.
}
// The linker loads implicit dependencies.
if p.Name == "main" && !p.Internal.ForceLibrary {
for _, dep := range LinkerDeps(p) {
addImport(dep)
}
}
// Check for case-insensitive collision of input files.
// To avoid problems on case-insensitive files, we reject any package
// where two different input files have equal names under a case-insensitive
// comparison.
inputs := p.AllFiles()
f1, f2 := str.FoldDup(inputs)
if f1 != "" {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("case-insensitive file name collision: %q and %q", f1, f2),
}
return
}
// If first letter of input file is ASCII, it must be alphanumeric.
// This avoids files turning into flags when invoking commands,
// and other problems we haven't thought of yet.
// Also, _cgo_ files must be generated by us, not supplied.
// They are allowed to have //go:cgo_ldflag directives.
// The directory scan ignores files beginning with _,
// so we shouldn't see any _cgo_ files anyway, but just be safe.
for _, file := range inputs {
if !SafeArg(file) || strings.HasPrefix(file, "_cgo_") {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("invalid input file name %q", file),
}
return
}
}
if name := pathpkg.Base(p.ImportPath); !SafeArg(name) {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("invalid input directory name %q", name),
}
return
}
if !SafeArg(p.ImportPath) {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("invalid import path %q", p.ImportPath),
}
return
}
// Build list of imported packages and full dependency list.
imports := make([]*Package, 0, len(p.Imports))
for i, path := range importPaths {
if path == "C" {
continue
}
p1 := LoadImport(path, p.Dir, p, stk, p.Internal.Build.ImportPos[path], ResolveImport)
if p.Standard && p.Error == nil && !p1.Standard && p1.Error == nil {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("non-standard import %q in standard package %q", path, p.ImportPath),
}
pos := p.Internal.Build.ImportPos[path]
if len(pos) > 0 {
p.Error.Pos = pos[0].String()
}
}
path = p1.ImportPath
importPaths[i] = path
if i < len(p.Imports) {
p.Imports[i] = path
}
imports = append(imports, p1)
if p1.Incomplete {
p.Incomplete = true
}
}
p.Internal.Imports = imports
deps := make(map[string]*Package)
var q []*Package
q = append(q, imports...)
for i := 0; i < len(q); i++ {
p1 := q[i]
path := p1.ImportPath
// The same import path could produce an error or not,
// depending on what tries to import it.
// Prefer to record entries with errors, so we can report them.
p0 := deps[path]
if p0 == nil || p1.Error != nil && (p0.Error == nil || len(p0.Error.ImportStack) > len(p1.Error.ImportStack)) {
deps[path] = p1
for _, p2 := range p1.Internal.Imports {
if deps[p2.ImportPath] != p2 {
q = append(q, p2)
}
}
}
}
p.Deps = make([]string, 0, len(deps))
for dep := range deps {
p.Deps = append(p.Deps, dep)
}
sort.Strings(p.Deps)
for _, dep := range p.Deps {
p1 := deps[dep]
if p1 == nil {
panic("impossible: missing entry in package cache for " + dep + " imported by " + p.ImportPath)
}
if p1.Error != nil {
p.DepsErrors = append(p.DepsErrors, p1.Error)
}
}
// unsafe is a fake package.
if p.Standard && (p.ImportPath == "unsafe" || cfg.BuildContext.Compiler == "gccgo") {
p.Target = ""
}
// If cgo is not enabled, ignore cgo supporting sources
// just as we ignore go files containing import "C".
if !cfg.BuildContext.CgoEnabled {
p.CFiles = nil
p.CXXFiles = nil
p.MFiles = nil
p.SwigFiles = nil
p.SwigCXXFiles = nil
// Note that SFiles are okay (they go to the Go assembler)
// and HFiles are okay (they might be used by the SFiles).
// Also Sysofiles are okay (they might not contain object
// code; see issue #16050).
}
setError := func(msg string) {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: msg,
}
}
// The gc toolchain only permits C source files with cgo or SWIG.
if len(p.CFiles) > 0 && !p.UsesCgo() && !p.UsesSwig() && cfg.BuildContext.Compiler == "gc" {
setError(fmt.Sprintf("C source files not allowed when not using cgo or SWIG: %s", strings.Join(p.CFiles, " ")))
return
}
// C++, Objective-C, and Fortran source files are permitted only with cgo or SWIG,
// regardless of toolchain.
if len(p.CXXFiles) > 0 && !p.UsesCgo() && !p.UsesSwig() {
setError(fmt.Sprintf("C++ source files not allowed when not using cgo or SWIG: %s", strings.Join(p.CXXFiles, " ")))
return
}
if len(p.MFiles) > 0 && !p.UsesCgo() && !p.UsesSwig() {
setError(fmt.Sprintf("Objective-C source files not allowed when not using cgo or SWIG: %s", strings.Join(p.MFiles, " ")))
return
}
if len(p.FFiles) > 0 && !p.UsesCgo() && !p.UsesSwig() {
setError(fmt.Sprintf("Fortran source files not allowed when not using cgo or SWIG: %s", strings.Join(p.FFiles, " ")))
return
}
// Check for case-insensitive collisions of import paths.
fold := str.ToFold(p.ImportPath)
if other := foldPath[fold]; other == "" {
foldPath[fold] = p.ImportPath
} else if other != p.ImportPath {
setError(fmt.Sprintf("case-insensitive import collision: %q and %q", p.ImportPath, other))
return
}
if cfg.ModulesEnabled {
p.Module = ModPackageModuleInfo(p.ImportPath)
if p.Name == "main" {
p.Internal.BuildInfo = ModPackageBuildInfo(p.ImportPath, p.Deps)
}
}
}
// SafeArg reports whether arg is a "safe" command-line argument,
// meaning that when it appears in a command-line, it probably
// doesn't have some special meaning other than its own name.
// Obviously args beginning with - are not safe (they look like flags).
// Less obviously, args beginning with @ are not safe (they look like
// GNU binutils flagfile specifiers, sometimes called "response files").
// To be conservative, we reject almost any arg beginning with non-alphanumeric ASCII.
// We accept leading . _ and / as likely in file system paths.
// There is a copy of this function in cmd/compile/internal/gc/noder.go.
func SafeArg(name string) bool {
if name == "" {
return false
}
c := name[0]
return '0' <= c && c <= '9' || 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z' || c == '.' || c == '_' || c == '/' || c >= utf8.RuneSelf
}
// LinkerDeps returns the list of linker-induced dependencies for main package p.
func LinkerDeps(p *Package) []string {
// Everything links runtime.
deps := []string{"runtime"}
// External linking mode forces an import of runtime/cgo.
if externalLinkingForced(p) && cfg.BuildContext.Compiler != "gccgo" {
deps = append(deps, "runtime/cgo")
}
// On ARM with GOARM=5, it forces an import of math, for soft floating point.
if cfg.Goarch == "arm" {
deps = append(deps, "math")
}
// Using the race detector forces an import of runtime/race.
if cfg.BuildRace {
deps = append(deps, "runtime/race")
}
// Using memory sanitizer forces an import of runtime/msan.
if cfg.BuildMSan {
deps = append(deps, "runtime/msan")
}
return deps
}
// externalLinkingForced reports whether external linking is being
// forced even for programs that do not use cgo.
func externalLinkingForced(p *Package) bool {
// Some targets must use external linking even inside GOROOT.
switch cfg.BuildContext.GOOS {
case "android":
return true
case "darwin":
switch cfg.BuildContext.GOARCH {
case "arm", "arm64":
return true
}
}
if !cfg.BuildContext.CgoEnabled {
return false
}
// Currently build modes c-shared, pie (on systems that do not
// support PIE with internal linking mode (currently all
// systems: issue #18968)), plugin, and -linkshared force
// external linking mode, as of course does
// -ldflags=-linkmode=external. External linking mode forces
// an import of runtime/cgo.
pieCgo := cfg.BuildBuildmode == "pie"
linkmodeExternal := false
if p != nil {
ldflags := BuildLdflags.For(p)
for i, a := range ldflags {
if a == "-linkmode=external" {
linkmodeExternal = true
}
if a == "-linkmode" && i+1 < len(ldflags) && ldflags[i+1] == "external" {
linkmodeExternal = true
}
}
}
return cfg.BuildBuildmode == "c-shared" || cfg.BuildBuildmode == "plugin" || pieCgo || cfg.BuildLinkshared || linkmodeExternal
}
// mkAbs rewrites list, which must be paths relative to p.Dir,
// into a sorted list of absolute paths. It edits list in place but for
// convenience also returns list back to its caller.
func (p *Package) mkAbs(list []string) []string {
for i, f := range list {
list[i] = filepath.Join(p.Dir, f)
}
sort.Strings(list)
return list
}
// InternalGoFiles returns the list of Go files being built for the package,
// using absolute paths.
func (p *Package) InternalGoFiles() []string {
return p.mkAbs(str.StringList(p.GoFiles, p.CgoFiles, p.TestGoFiles))
}
// InternalXGoFiles returns the list of Go files being built for the XTest package,
// using absolute paths.
func (p *Package) InternalXGoFiles() []string {
return p.mkAbs(p.XTestGoFiles)
}
// InternalGoFiles returns the list of all Go files possibly relevant for the package,
// using absolute paths. "Possibly relevant" means that files are not excluded
// due to build tags, but files with names beginning with . or _ are still excluded.
func (p *Package) InternalAllGoFiles() []string {
var extra []string
for _, f := range p.IgnoredGoFiles {
if f != "" && f[0] != '.' || f[0] != '_' {
extra = append(extra, f)
}
}
return p.mkAbs(str.StringList(extra, p.GoFiles, p.CgoFiles, p.TestGoFiles, p.XTestGoFiles))
}
// usesSwig reports whether the package needs to run SWIG.
func (p *Package) UsesSwig() bool {
return len(p.SwigFiles) > 0 || len(p.SwigCXXFiles) > 0
}
// usesCgo reports whether the package needs to run cgo
func (p *Package) UsesCgo() bool {
return len(p.CgoFiles) > 0
}
// packageList returns the list of packages in the dag rooted at roots
// as visited in a depth-first post-order traversal.
func PackageList(roots []*Package) []*Package {
seen := map[*Package]bool{}
all := []*Package{}
var walk func(*Package)
walk = func(p *Package) {
if seen[p] {
return
}
seen[p] = true
for _, p1 := range p.Internal.Imports {
walk(p1)
}
all = append(all, p)
}
for _, root := range roots {
walk(root)
}
return all
}
var cmdCache = map[string]*Package{}
func ClearCmdCache() {
for name := range cmdCache {
delete(cmdCache, name)
}
}
// loadPackage is like loadImport but is used for command-line arguments,
// not for paths found in import statements. In addition to ordinary import paths,
// loadPackage accepts pseudo-paths beginning with cmd/ to denote commands
// in the Go command directory, as well as paths to those directories.
func LoadPackage(arg string, stk *ImportStack) *Package {
if build.IsLocalImport(arg) {
dir := arg
if !filepath.IsAbs(dir) {
if abs, err := filepath.Abs(dir); err == nil {
// interpret relative to current directory
dir = abs
}
}
if sub, ok := hasSubdir(cfg.GOROOTsrc, dir); ok && strings.HasPrefix(sub, "cmd/") && !strings.Contains(sub[4:], "/") {
arg = sub
}
}
if strings.HasPrefix(arg, "cmd/") && !strings.Contains(arg[4:], "/") {
if p := cmdCache[arg]; p != nil {
return p
}
stk.Push(arg)
defer stk.Pop()
bp, err := cfg.BuildContext.ImportDir(filepath.Join(cfg.GOROOTsrc, arg), 0)
bp.ImportPath = arg
bp.Goroot = true
bp.BinDir = cfg.GOROOTbin
if cfg.GOROOTbin != "" {
bp.BinDir = cfg.GOROOTbin
}
bp.Root = cfg.GOROOT
bp.SrcRoot = cfg.GOROOTsrc
p := new(Package)
cmdCache[arg] = p
p.load(stk, bp, err)
if p.Error == nil && p.Name != "main" {
p.Error = &PackageError{
ImportStack: stk.Copy(),
Err: fmt.Sprintf("expected package main but found package %s in %s", p.Name, p.Dir),
}
}
return p
}
// Wasn't a command; must be a package.
// If it is a local import path but names a standard package,
// we treat it as if the user specified the standard package.
// This lets you run go test ./ioutil in package io and be
// referring to io/ioutil rather than a hypothetical import of
// "./ioutil".
if build.IsLocalImport(arg) {
bp, _ := cfg.BuildContext.ImportDir(filepath.Join(base.Cwd, arg), build.FindOnly)
if bp.ImportPath != "" && bp.ImportPath != "." {
arg = bp.ImportPath
}
}
return LoadImport(arg, base.Cwd, nil, stk, nil, 0)
}
// packages returns the packages named by the
// command line arguments 'args'. If a named package
// cannot be loaded at all (for example, if the directory does not exist),
// then packages prints an error and does not include that
// package in the results. However, if errors occur trying
// to load dependencies of a named package, the named
// package is still returned, with p.Incomplete = true
// and details in p.DepsErrors.
func Packages(args []string) []*Package {
var pkgs []*Package
for _, pkg := range PackagesAndErrors(args) {
if pkg.Error != nil {
base.Errorf("can't load package: %s", pkg.Error)
continue
}
pkgs = append(pkgs, pkg)
}
return pkgs
}
// packagesAndErrors is like 'packages' but returns a
// *Package for every argument, even the ones that
// cannot be loaded at all.
// The packages that fail to load will have p.Error != nil.
func PackagesAndErrors(args []string) []*Package {
if len(args) > 0 && strings.HasSuffix(args[0], ".go") {
return []*Package{GoFilesPackage(args)}
}
args = ImportPaths(args)
var (
pkgs []*Package
stk ImportStack
seenArg = make(map[string]bool)
seenPkg = make(map[*Package]bool)
)
for _, arg := range args {
if seenArg[arg] {
continue
}
seenArg[arg] = true
pkg := LoadPackage(arg, &stk)
if seenPkg[pkg] {
continue
}
seenPkg[pkg] = true
pkgs = append(pkgs, pkg)
}
return pkgs
}
func ImportPaths(args []string) []string {
if cmdlineMatchers == nil {
SetCmdlinePatterns(search.CleanImportPaths(args))
}
if cfg.ModulesEnabled {
return ModImportPaths(args)
}
return search.ImportPaths(args)
}
func ImportPathsForGoGet(args []string) []string {
if cmdlineMatchers == nil {
SetCmdlinePatterns(search.CleanImportPaths(args))
}
return search.ImportPathsNoDotExpansion(args)
}
// packagesForBuild is like 'packages' but fails if any of
// the packages or their dependencies have errors
// (cannot be built).
func PackagesForBuild(args []string) []*Package {
pkgs := PackagesAndErrors(args)
printed := map[*PackageError]bool{}
for _, pkg := range pkgs {
if pkg.Error != nil {
base.Errorf("can't load package: %s", pkg.Error)
printed[pkg.Error] = true
}
for _, err := range pkg.DepsErrors {
// Since these are errors in dependencies,
// the same error might show up multiple times,
// once in each package that depends on it.
// Only print each once.
if !printed[err] {
printed[err] = true
base.Errorf("%s", err)
}
}
}
base.ExitIfErrors()
// Check for duplicate loads of the same package.
// That should be impossible, but if it does happen then
// we end up trying to build the same package twice,
// usually in parallel overwriting the same files,
// which doesn't work very well.
seen := map[string]bool{}
reported := map[string]bool{}
for _, pkg := range PackageList(pkgs) {
if seen[pkg.ImportPath] && !reported[pkg.ImportPath] {
reported[pkg.ImportPath] = true
base.Errorf("internal error: duplicate loads of %s", pkg.ImportPath)
}
seen[pkg.ImportPath] = true
}
base.ExitIfErrors()
return pkgs
}
// GoFilesPackage creates a package for building a collection of Go files
// (typically named on the command line). The target is named p.a for
// package p or named after the first Go file for package main.
func GoFilesPackage(gofiles []string) *Package {
// TODO: Remove this restriction.
for _, f := range gofiles {
if !strings.HasSuffix(f, ".go") {
base.Fatalf("named files must be .go files")
}
}
var stk ImportStack
ctxt := cfg.BuildContext
ctxt.UseAllFiles = true
// Synthesize fake "directory" that only shows the named files,
// to make it look like this is a standard package or
// command directory. So that local imports resolve
// consistently, the files must all be in the same directory.
var dirent []os.FileInfo
var dir string
for _, file := range gofiles {
fi, err := os.Stat(file)
if err != nil {
base.Fatalf("%s", err)
}
if fi.IsDir() {
base.Fatalf("%s is a directory, should be a Go file", file)
}
dir1, _ := filepath.Split(file)
if dir1 == "" {
dir1 = "./"
}
if dir == "" {
dir = dir1
} else if dir != dir1 {
base.Fatalf("named files must all be in one directory; have %s and %s", dir, dir1)
}
dirent = append(dirent, fi)
}
ctxt.ReadDir = func(string) ([]os.FileInfo, error) { return dirent, nil }
if cfg.ModulesEnabled {
ModImportFromFiles(gofiles)
}
var err error
if dir == "" {
dir = base.Cwd
}
dir, err = filepath.Abs(dir)
if err != nil {
base.Fatalf("%s", err)
}
bp, err := ctxt.ImportDir(dir, 0)
pkg := new(Package)
pkg.Internal.Local = true
pkg.Internal.CmdlineFiles = true
stk.Push("main")
pkg.load(&stk, bp, err)
stk.Pop()
pkg.Internal.LocalPrefix = dirToImportPath(dir)
pkg.ImportPath = "command-line-arguments"
pkg.Target = ""
if pkg.Name == "main" {
_, elem := filepath.Split(gofiles[0])
exe := elem[:len(elem)-len(".go")] + cfg.ExeSuffix
if cfg.BuildO == "" {
cfg.BuildO = exe
}
if cfg.GOBIN != "" {
pkg.Target = filepath.Join(cfg.GOBIN, exe)
} else if cfg.ModulesEnabled {
pkg.Target = filepath.Join(ModBinDir(), exe)
}
}
return pkg
}