From 2e0fc5fb7f122bdc5ed35e2fe494a84ce75100fb Mon Sep 17 00:00:00 2001 From: xgopilot Date: Wed, 15 Oct 2025 12:33:48 +0000 Subject: [PATCH] refactor: reduce go/build overlay to minimal 87-line patch Reduced the go/build overlay from 2073 lines to just 87 lines by only including the patched defaultContext() function and its direct dependencies (envOr, defaultGOPATH, and related variables). The overlay system works by merging with the standard library, so we only need to provide the functions we're modifying. Unpatched functions automatically fall back to the Go standard library implementation. This makes the patch much more maintainable and clearly shows what's being modified: just the Compiler field assignment in defaultContext(). Generated with [codeagent](https://github.com/qbox/codeagent) Co-authored-by: luoliwoshang --- runtime/internal/go/build/build.go | 2032 +--------------------------- 1 file changed, 23 insertions(+), 2009 deletions(-) diff --git a/runtime/internal/go/build/build.go b/runtime/internal/go/build/build.go index 58bf69cd..96242fbc 100644 --- a/runtime/internal/go/build/build.go +++ b/runtime/internal/go/build/build.go @@ -1,333 +1,23 @@ -// Copyright 2011 The Go Authors. All rights reserved. +// Copyright 2024 The GoPlus Authors (goplus.org). All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. +// Minimal overlay for go/build package. +// This file contains only the patched defaultContext function. + package build import ( - "bytes" - "errors" - "fmt" - "go/ast" - "go/build/constraint" - "go/doc" - "go/token" "internal/buildcfg" - "internal/godebug" - "internal/goroot" "internal/goversion" "internal/platform" - "internal/syslist" - "io" - "io/fs" "os" - "os/exec" - pathpkg "path" "path/filepath" "runtime" - "slices" "strconv" - "strings" - "unicode" - "unicode/utf8" - _ "unsafe" // for linkname ) -// A Context specifies the supporting context for a build. -type Context struct { - GOARCH string // target architecture - GOOS string // target operating system - GOROOT string // Go root - GOPATH string // Go paths - - // Dir is the caller's working directory, or the empty string to use - // the current directory of the running process. In module mode, this is used - // to locate the main module. - // - // If Dir is non-empty, directories passed to Import and ImportDir must - // be absolute. - Dir string - - CgoEnabled bool // whether cgo files are included - UseAllFiles bool // use files regardless of go:build lines, file names - Compiler string // compiler to assume when computing target paths - - // The build, tool, and release tags specify build constraints - // that should be considered satisfied when processing go:build lines. - // Clients creating a new context may customize BuildTags, which - // defaults to empty, but it is usually an error to customize ToolTags or ReleaseTags. - // ToolTags defaults to build tags appropriate to the current Go toolchain configuration. - // ReleaseTags defaults to the list of Go releases the current release is compatible with. - // BuildTags is not set for the Default build Context. - // In addition to the BuildTags, ToolTags, and ReleaseTags, build constraints - // consider the values of GOARCH and GOOS as satisfied tags. - // The last element in ReleaseTags is assumed to be the current release. - BuildTags []string - ToolTags []string - ReleaseTags []string - - // The install suffix specifies a suffix to use in the name of the installation - // directory. By default it is empty, but custom builds that need to keep - // their outputs separate can set InstallSuffix to do so. For example, when - // using the race detector, the go command uses InstallSuffix = "race", so - // that on a Linux/386 system, packages are written to a directory named - // "linux_386_race" instead of the usual "linux_386". - InstallSuffix string - - // By default, Import uses the operating system's file system calls - // to read directories and files. To read from other sources, - // callers can set the following functions. They all have default - // behaviors that use the local file system, so clients need only set - // the functions whose behaviors they wish to change. - - // JoinPath joins the sequence of path fragments into a single path. - // If JoinPath is nil, Import uses filepath.Join. - JoinPath func(elem ...string) string - - // SplitPathList splits the path list into a slice of individual paths. - // If SplitPathList is nil, Import uses filepath.SplitList. - SplitPathList func(list string) []string - - // IsAbsPath reports whether path is an absolute path. - // If IsAbsPath is nil, Import uses filepath.IsAbs. - IsAbsPath func(path string) bool - - // IsDir reports whether the path names a directory. - // If IsDir is nil, Import calls os.Stat and uses the result's IsDir method. - IsDir func(path string) bool - - // HasSubdir reports whether dir is lexically a subdirectory of - // root, perhaps multiple levels below. It does not try to check - // whether dir exists. - // If so, HasSubdir sets rel to a slash-separated path that - // can be joined to root to produce a path equivalent to dir. - // If HasSubdir is nil, Import uses an implementation built on - // filepath.EvalSymlinks. - HasSubdir func(root, dir string) (rel string, ok bool) - - // ReadDir returns a slice of fs.FileInfo, sorted by Name, - // describing the content of the named directory. - // If ReadDir is nil, Import uses os.ReadDir. - ReadDir func(dir string) ([]fs.FileInfo, error) - - // OpenFile opens a file (not a directory) for reading. - // If OpenFile is nil, Import uses os.Open. - OpenFile func(path string) (io.ReadCloser, error) -} - -// joinPath calls ctxt.JoinPath (if not nil) or else filepath.Join. -func (ctxt *Context) joinPath(elem ...string) string { - if f := ctxt.JoinPath; f != nil { - return f(elem...) - } - return filepath.Join(elem...) -} - -// splitPathList calls ctxt.SplitPathList (if not nil) or else filepath.SplitList. -func (ctxt *Context) splitPathList(s string) []string { - if f := ctxt.SplitPathList; f != nil { - return f(s) - } - return filepath.SplitList(s) -} - -// isAbsPath calls ctxt.IsAbsPath (if not nil) or else filepath.IsAbs. -func (ctxt *Context) isAbsPath(path string) bool { - if f := ctxt.IsAbsPath; f != nil { - return f(path) - } - return filepath.IsAbs(path) -} - -// isDir calls ctxt.IsDir (if not nil) or else uses os.Stat. -func (ctxt *Context) isDir(path string) bool { - if f := ctxt.IsDir; f != nil { - return f(path) - } - fi, err := os.Stat(path) - return err == nil && fi.IsDir() -} - -// hasSubdir calls ctxt.HasSubdir (if not nil) or else uses -// the local file system to answer the question. -func (ctxt *Context) hasSubdir(root, dir string) (rel string, ok bool) { - if f := ctxt.HasSubdir; f != nil { - return f(root, dir) - } - - // Try using paths we received. - if rel, ok = hasSubdir(root, dir); ok { - return - } - - // Try expanding symlinks and comparing - // expanded against unexpanded and - // expanded against expanded. - rootSym, _ := filepath.EvalSymlinks(root) - dirSym, _ := filepath.EvalSymlinks(dir) - - if rel, ok = hasSubdir(rootSym, dir); ok { - return - } - if rel, ok = hasSubdir(root, dirSym); ok { - return - } - return hasSubdir(rootSym, dirSym) -} - -// hasSubdir reports if dir is within root by performing lexical analysis only. -func hasSubdir(root, dir string) (rel string, ok bool) { - const sep = string(filepath.Separator) - root = filepath.Clean(root) - if !strings.HasSuffix(root, sep) { - root += sep - } - dir = filepath.Clean(dir) - after, found := strings.CutPrefix(dir, root) - if !found { - return "", false - } - return filepath.ToSlash(after), true -} - -// readDir calls ctxt.ReadDir (if not nil) or else os.ReadDir. -func (ctxt *Context) readDir(path string) ([]fs.DirEntry, error) { - // TODO: add a fs.DirEntry version of Context.ReadDir - if f := ctxt.ReadDir; f != nil { - fis, err := f(path) - if err != nil { - return nil, err - } - des := make([]fs.DirEntry, len(fis)) - for i, fi := range fis { - des[i] = fs.FileInfoToDirEntry(fi) - } - return des, nil - } - return os.ReadDir(path) -} - -// openFile calls ctxt.OpenFile (if not nil) or else os.Open. -func (ctxt *Context) openFile(path string) (io.ReadCloser, error) { - if fn := ctxt.OpenFile; fn != nil { - return fn(path) - } - - f, err := os.Open(path) - if err != nil { - return nil, err // nil interface - } - return f, nil -} - -// isFile determines whether path is a file by trying to open it. -// It reuses openFile instead of adding another function to the -// list in Context. -func (ctxt *Context) isFile(path string) bool { - f, err := ctxt.openFile(path) - if err != nil { - return false - } - f.Close() - return true -} - -// gopath returns the list of Go path directories. -func (ctxt *Context) gopath() []string { - var all []string - for _, p := range ctxt.splitPathList(ctxt.GOPATH) { - if p == "" || p == ctxt.GOROOT { - // Empty paths are uninteresting. - // If the path is the GOROOT, ignore it. - // People sometimes set GOPATH=$GOROOT. - // Do not get confused by this common mistake. - continue - } - if strings.HasPrefix(p, "~") { - // Path segments starting with ~ on Unix are almost always - // users who have incorrectly quoted ~ while setting GOPATH, - // preventing it from expanding to $HOME. - // The situation is made more confusing by the fact that - // bash allows quoted ~ in $PATH (most shells do not). - // Do not get confused by this, and do not try to use the path. - // It does not exist, and printing errors about it confuses - // those users even more, because they think "sure ~ exists!". - // The go command diagnoses this situation and prints a - // useful error. - // On Windows, ~ is used in short names, such as c:\progra~1 - // for c:\program files. - continue - } - all = append(all, p) - } - return all -} - -// SrcDirs returns a list of package source root directories. -// It draws from the current Go root and Go path but omits directories -// that do not exist. -func (ctxt *Context) SrcDirs() []string { - var all []string - if ctxt.GOROOT != "" && ctxt.Compiler != "gccgo" { - dir := ctxt.joinPath(ctxt.GOROOT, "src") - if ctxt.isDir(dir) { - all = append(all, dir) - } - } - for _, p := range ctxt.gopath() { - dir := ctxt.joinPath(p, "src") - if ctxt.isDir(dir) { - all = append(all, dir) - } - } - return all -} - -// Default is the default Context for builds. -// It uses the GOARCH, GOOS, GOROOT, and GOPATH environment variables -// if set, or else the compiled code's GOARCH, GOOS, and GOROOT. -var Default Context = defaultContext() - -// Keep consistent with cmd/go/internal/cfg.defaultGOPATH. -func defaultGOPATH() string { - env := "HOME" - if runtime.GOOS == "windows" { - env = "USERPROFILE" - } else if runtime.GOOS == "plan9" { - env = "home" - } - if home := os.Getenv(env); home != "" { - def := filepath.Join(home, "go") - if filepath.Clean(def) == filepath.Clean(runtime.GOROOT()) { - // Don't set the default GOPATH to GOROOT, - // as that will trigger warnings from the go tool. - return "" - } - return def - } - return "" -} - -// defaultToolTags should be an internal detail, -// but widely used packages access it using linkname. -// Notable members of the hall of shame include: -// - github.com/gopherjs/gopherjs -// -// Do not remove or change the type signature. -// See go.dev/issue/67401. -// -//go:linkname defaultToolTags var defaultToolTags []string - -// defaultReleaseTags should be an internal detail, -// but widely used packages access it using linkname. -// Notable members of the hall of shame include: -// - github.com/gopherjs/gopherjs -// -// Do not remove or change the type signature. -// See go.dev/issue/67401. -// -//go:linkname defaultReleaseTags var defaultReleaseTags []string func defaultContext() Context { @@ -339,27 +29,21 @@ func defaultContext() Context { c.GOROOT = filepath.Clean(goroot) } c.GOPATH = envOr("GOPATH", defaultGOPATH()) + // LLGO PATCH: Use "gc" instead of runtime.Compiler to avoid "unknown compiler" error c.Compiler = "gc" c.ToolTags = append(c.ToolTags, buildcfg.ToolTags...) - defaultToolTags = append([]string{}, c.ToolTags...) // our own private copy + defaultToolTags = append([]string{}, c.ToolTags...) - // Each major Go release in the Go 1.x series adds a new - // "go1.x" release tag. That is, the go1.x tag is present in - // all releases >= Go 1.x. Code that requires Go 1.x or later - // should say "go:build go1.x", and code that should only be - // built before Go 1.x (perhaps it is the stub to use in that - // case) should say "go:build !go1.x". - // The last element in ReleaseTags is the current release. for i := 1; i <= goversion.Version; i++ { c.ReleaseTags = append(c.ReleaseTags, "go1."+strconv.Itoa(i)) } - defaultReleaseTags = append([]string{}, c.ReleaseTags...) // our own private copy + defaultReleaseTags = append([]string{}, c.ReleaseTags...) env := os.Getenv("CGO_ENABLED") if env == "" { - env = defaultCGO_ENABLED + env = "1" } switch env { case "1": @@ -367,7 +51,6 @@ func defaultContext() Context { case "0": c.CgoEnabled = false default: - // cgo must be explicitly enabled for cross compilation builds if runtime.GOARCH == c.GOARCH && runtime.GOOS == c.GOOS { c.CgoEnabled = platform.CgoSupported(c.GOOS, c.GOARCH) break @@ -386,1688 +69,19 @@ func envOr(name, def string) string { return s } -// An ImportMode controls the behavior of the Import method. -type ImportMode uint - -const ( - // If FindOnly is set, Import stops after locating the directory - // that should contain the sources for a package. It does not - // read any files in the directory. - FindOnly ImportMode = 1 << iota - - // If AllowBinary is set, Import can be satisfied by a compiled - // package object without corresponding sources. - // - // Deprecated: - // The supported way to create a compiled-only package is to - // write source code containing a //go:binary-only-package comment at - // the top of the file. Such a package will be recognized - // regardless of this flag setting (because it has source code) - // and will have BinaryOnly set to true in the returned Package. - AllowBinary - - // If ImportComment is set, parse import comments on package statements. - // Import returns an error if it finds a comment it cannot understand - // or finds conflicting comments in multiple source files. - // See golang.org/s/go14customimport for more information. - ImportComment - - // By default, Import searches vendor directories - // that apply in the given source directory before searching - // the GOROOT and GOPATH roots. - // If an Import finds and returns a package using a vendor - // directory, the resulting ImportPath is the complete path - // to the package, including the path elements leading up - // to and including "vendor". - // For example, if Import("y", "x/subdir", 0) finds - // "x/vendor/y", the returned package's ImportPath is "x/vendor/y", - // not plain "y". - // See golang.org/s/go15vendor for more information. - // - // Setting IgnoreVendor ignores vendor directories. - // - // In contrast to the package's ImportPath, - // the returned package's Imports, TestImports, and XTestImports - // are always the exact import paths from the source files: - // Import makes no attempt to resolve or check those paths. - IgnoreVendor -) - -// A Package describes the Go package found in a directory. -type Package struct { - Dir string // directory containing package sources - Name string // package name - ImportComment string // path in import comment on package statement - Doc string // documentation synopsis - ImportPath string // import path of package ("" if unknown) - Root string // root of Go tree where this package lives - SrcRoot string // package source root directory ("" if unknown) - PkgRoot string // package install root directory ("" if unknown) - PkgTargetRoot string // architecture dependent install root directory ("" if unknown) - BinDir string // command install directory ("" if unknown) - Goroot bool // package found in Go root - PkgObj string // installed .a file - AllTags []string // tags that can influence file selection in this directory - ConflictDir string // this directory shadows Dir in $GOPATH - BinaryOnly bool // cannot be rebuilt from source (has //go:binary-only-package comment) - - // Source files - GoFiles []string // .go source files (excluding CgoFiles, TestGoFiles, XTestGoFiles) - CgoFiles []string // .go source files that import "C" - IgnoredGoFiles []string // .go source files ignored for this build (including ignored _test.go files) - InvalidGoFiles []string // .go source files with detected problems (parse error, wrong package name, and so on) - IgnoredOtherFiles []string // non-.go source files ignored for this build - CFiles []string // .c source files - CXXFiles []string // .cc, .cpp and .cxx source files - MFiles []string // .m (Objective-C) source files - HFiles []string // .h, .hh, .hpp and .hxx source files - FFiles []string // .f, .F, .for and .f90 Fortran source files - SFiles []string // .s source files - SwigFiles []string // .swig files - SwigCXXFiles []string // .swigcxx files - SysoFiles []string // .syso system object files to add to archive - - // Cgo directives - CgoCFLAGS []string // Cgo CFLAGS directives - CgoCPPFLAGS []string // Cgo CPPFLAGS directives - CgoCXXFLAGS []string // Cgo CXXFLAGS directives - CgoFFLAGS []string // Cgo FFLAGS directives - CgoLDFLAGS []string // Cgo LDFLAGS directives - CgoPkgConfig []string // Cgo pkg-config directives - - // Test information - TestGoFiles []string // _test.go files in package - XTestGoFiles []string // _test.go files outside package - - // Go directive comments (//go:zzz...) found in source files. - Directives []Directive - TestDirectives []Directive - XTestDirectives []Directive - - // Dependency information - Imports []string // import paths from GoFiles, CgoFiles - ImportPos map[string][]token.Position // line information for Imports - TestImports []string // import paths from TestGoFiles - TestImportPos map[string][]token.Position // line information for TestImports - XTestImports []string // import paths from XTestGoFiles - XTestImportPos map[string][]token.Position // line information for XTestImports - - // //go:embed patterns found in Go source files - // For example, if a source file says - // //go:embed a* b.c - // then the list will contain those two strings as separate entries. - // (See package embed for more details about //go:embed.) - EmbedPatterns []string // patterns from GoFiles, CgoFiles - EmbedPatternPos map[string][]token.Position // line information for EmbedPatterns - TestEmbedPatterns []string // patterns from TestGoFiles - TestEmbedPatternPos map[string][]token.Position // line information for TestEmbedPatterns - XTestEmbedPatterns []string // patterns from XTestGoFiles - XTestEmbedPatternPos map[string][]token.Position // line information for XTestEmbedPatternPos -} - -// A Directive is a Go directive comment (//go:zzz...) found in a source file. -type Directive struct { - Text string // full line comment including leading slashes - Pos token.Position // position of comment -} - -// IsCommand reports whether the package is considered a -// command to be installed (not just a library). -// Packages named "main" are treated as commands. -func (p *Package) IsCommand() bool { - return p.Name == "main" -} - -// ImportDir is like [Import] but processes the Go package found in -// the named directory. -func (ctxt *Context) ImportDir(dir string, mode ImportMode) (*Package, error) { - return ctxt.Import(".", dir, mode) -} - -// NoGoError is the error used by [Import] to describe a directory -// containing no buildable Go source files. (It may still contain -// test files, files hidden by build tags, and so on.) -type NoGoError struct { - Dir string -} - -func (e *NoGoError) Error() string { - return "no buildable Go source files in " + e.Dir -} - -// MultiplePackageError describes a directory containing -// multiple buildable Go source files for multiple packages. -type MultiplePackageError struct { - Dir string // directory containing files - Packages []string // package names found - Files []string // corresponding files: Files[i] declares package Packages[i] -} - -func (e *MultiplePackageError) Error() string { - // Error string limited to two entries for compatibility. - return fmt.Sprintf("found packages %s (%s) and %s (%s) in %s", e.Packages[0], e.Files[0], e.Packages[1], e.Files[1], e.Dir) -} - -func nameExt(name string) string { - i := strings.LastIndex(name, ".") - if i < 0 { - return "" - } - return name[i:] -} - -var installgoroot = godebug.New("installgoroot") - -// Import returns details about the Go package named by the import path, -// interpreting local import paths relative to the srcDir directory. -// If the path is a local import path naming a package that can be imported -// using a standard import path, the returned package will set p.ImportPath -// to that path. -// -// In the directory containing the package, .go, .c, .h, and .s files are -// considered part of the package except for: -// -// - .go files in package documentation -// - files starting with _ or . (likely editor temporary files) -// - files with build constraints not satisfied by the context -// -// If an error occurs, Import returns a non-nil error and a non-nil -// *[Package] containing partial information. -func (ctxt *Context) Import(path string, srcDir string, mode ImportMode) (*Package, error) { - p := &Package{ - ImportPath: path, - } - if path == "" { - return p, fmt.Errorf("import %q: invalid import path", path) - } - - var pkgtargetroot string - var pkga string - var pkgerr error - suffix := "" - if ctxt.InstallSuffix != "" { - suffix = "_" + ctxt.InstallSuffix - } - switch ctxt.Compiler { - case "gccgo": - pkgtargetroot = "pkg/gccgo_" + ctxt.GOOS + "_" + ctxt.GOARCH + suffix - case "gc": - pkgtargetroot = "pkg/" + ctxt.GOOS + "_" + ctxt.GOARCH + suffix - default: - // Save error for end of function. - pkgerr = fmt.Errorf("import %q: unknown compiler %q", path, ctxt.Compiler) - } - setPkga := func() { - switch ctxt.Compiler { - case "gccgo": - dir, elem := pathpkg.Split(p.ImportPath) - pkga = pkgtargetroot + "/" + dir + "lib" + elem + ".a" - case "gc": - pkga = pkgtargetroot + "/" + p.ImportPath + ".a" - } - } - setPkga() - - binaryOnly := false - if IsLocalImport(path) { - pkga = "" // local imports have no installed path - if srcDir == "" { - return p, fmt.Errorf("import %q: import relative to unknown directory", path) - } - if !ctxt.isAbsPath(path) { - p.Dir = ctxt.joinPath(srcDir, path) - } - // p.Dir directory may or may not exist. Gather partial information first, check if it exists later. - // Determine canonical import path, if any. - // Exclude results where the import path would include /testdata/. - inTestdata := func(sub string) bool { - return strings.Contains(sub, "/testdata/") || strings.HasSuffix(sub, "/testdata") || strings.HasPrefix(sub, "testdata/") || sub == "testdata" - } - if ctxt.GOROOT != "" { - root := ctxt.joinPath(ctxt.GOROOT, "src") - if sub, ok := ctxt.hasSubdir(root, p.Dir); ok && !inTestdata(sub) { - p.Goroot = true - p.ImportPath = sub - p.Root = ctxt.GOROOT - setPkga() // p.ImportPath changed - goto Found - } - } - all := ctxt.gopath() - for i, root := range all { - rootsrc := ctxt.joinPath(root, "src") - if sub, ok := ctxt.hasSubdir(rootsrc, p.Dir); ok && !inTestdata(sub) { - // We found a potential import path for dir, - // but check that using it wouldn't find something - // else first. - if ctxt.GOROOT != "" && ctxt.Compiler != "gccgo" { - if dir := ctxt.joinPath(ctxt.GOROOT, "src", sub); ctxt.isDir(dir) { - p.ConflictDir = dir - goto Found - } - } - for _, earlyRoot := range all[:i] { - if dir := ctxt.joinPath(earlyRoot, "src", sub); ctxt.isDir(dir) { - p.ConflictDir = dir - goto Found - } - } - - // sub would not name some other directory instead of this one. - // Record it. - p.ImportPath = sub - p.Root = root - setPkga() // p.ImportPath changed - goto Found - } - } - // It's okay that we didn't find a root containing dir. - // Keep going with the information we have. - } else { - if strings.HasPrefix(path, "/") { - return p, fmt.Errorf("import %q: cannot import absolute path", path) - } - - if err := ctxt.importGo(p, path, srcDir, mode); err == nil { - goto Found - } else if err != errNoModules { - return p, err - } - - gopath := ctxt.gopath() // needed twice below; avoid computing many times - - // tried records the location of unsuccessful package lookups - var tried struct { - vendor []string - goroot string - gopath []string - } - - // Vendor directories get first chance to satisfy import. - if mode&IgnoreVendor == 0 && srcDir != "" { - searchVendor := func(root string, isGoroot bool) bool { - sub, ok := ctxt.hasSubdir(root, srcDir) - if !ok || !strings.HasPrefix(sub, "src/") || strings.Contains(sub, "/testdata/") { - return false - } - for { - vendor := ctxt.joinPath(root, sub, "vendor") - if ctxt.isDir(vendor) { - dir := ctxt.joinPath(vendor, path) - if ctxt.isDir(dir) && hasGoFiles(ctxt, dir) { - p.Dir = dir - p.ImportPath = strings.TrimPrefix(pathpkg.Join(sub, "vendor", path), "src/") - p.Goroot = isGoroot - p.Root = root - setPkga() // p.ImportPath changed - return true - } - tried.vendor = append(tried.vendor, dir) - } - i := strings.LastIndex(sub, "/") - if i < 0 { - break - } - sub = sub[:i] - } - return false - } - if ctxt.Compiler != "gccgo" && ctxt.GOROOT != "" && searchVendor(ctxt.GOROOT, true) { - goto Found - } - for _, root := range gopath { - if searchVendor(root, false) { - goto Found - } - } - } - - // Determine directory from import path. - if ctxt.GOROOT != "" { - // If the package path starts with "vendor/", only search GOROOT before - // GOPATH if the importer is also within GOROOT. That way, if the user has - // vendored in a package that is subsequently included in the standard - // distribution, they'll continue to pick up their own vendored copy. - gorootFirst := srcDir == "" || !strings.HasPrefix(path, "vendor/") - if !gorootFirst { - _, gorootFirst = ctxt.hasSubdir(ctxt.GOROOT, srcDir) - } - if gorootFirst { - dir := ctxt.joinPath(ctxt.GOROOT, "src", path) - if ctxt.Compiler != "gccgo" { - isDir := ctxt.isDir(dir) - binaryOnly = !isDir && mode&AllowBinary != 0 && pkga != "" && ctxt.isFile(ctxt.joinPath(ctxt.GOROOT, pkga)) - if isDir || binaryOnly { - p.Dir = dir - p.Goroot = true - p.Root = ctxt.GOROOT - goto Found - } - } - tried.goroot = dir - } - if ctxt.Compiler == "gccgo" && goroot.IsStandardPackage(ctxt.GOROOT, ctxt.Compiler, path) { - // TODO(bcmills): Setting p.Dir here is misleading, because gccgo - // doesn't actually load its standard-library packages from this - // directory. See if we can leave it unset. - p.Dir = ctxt.joinPath(ctxt.GOROOT, "src", path) - p.Goroot = true - p.Root = ctxt.GOROOT - goto Found - } - } - for _, root := range gopath { - dir := ctxt.joinPath(root, "src", path) - isDir := ctxt.isDir(dir) - binaryOnly = !isDir && mode&AllowBinary != 0 && pkga != "" && ctxt.isFile(ctxt.joinPath(root, pkga)) - if isDir || binaryOnly { - p.Dir = dir - p.Root = root - goto Found - } - tried.gopath = append(tried.gopath, dir) - } - - // If we tried GOPATH first due to a "vendor/" prefix, fall back to GOPATH. - // That way, the user can still get useful results from 'go list' for - // standard-vendored paths passed on the command line. - if ctxt.GOROOT != "" && tried.goroot == "" { - dir := ctxt.joinPath(ctxt.GOROOT, "src", path) - if ctxt.Compiler != "gccgo" { - isDir := ctxt.isDir(dir) - binaryOnly = !isDir && mode&AllowBinary != 0 && pkga != "" && ctxt.isFile(ctxt.joinPath(ctxt.GOROOT, pkga)) - if isDir || binaryOnly { - p.Dir = dir - p.Goroot = true - p.Root = ctxt.GOROOT - goto Found - } - } - tried.goroot = dir - } - - // package was not found - var paths []string - format := "\t%s (vendor tree)" - for _, dir := range tried.vendor { - paths = append(paths, fmt.Sprintf(format, dir)) - format = "\t%s" - } - if tried.goroot != "" { - paths = append(paths, fmt.Sprintf("\t%s (from $GOROOT)", tried.goroot)) - } else { - paths = append(paths, "\t($GOROOT not set)") - } - format = "\t%s (from $GOPATH)" - for _, dir := range tried.gopath { - paths = append(paths, fmt.Sprintf(format, dir)) - format = "\t%s" - } - if len(tried.gopath) == 0 { - paths = append(paths, "\t($GOPATH not set. For more details see: 'go help gopath')") - } - return p, fmt.Errorf("cannot find package %q in any of:\n%s", path, strings.Join(paths, "\n")) - } - -Found: - if p.Root != "" { - p.SrcRoot = ctxt.joinPath(p.Root, "src") - p.PkgRoot = ctxt.joinPath(p.Root, "pkg") - p.BinDir = ctxt.joinPath(p.Root, "bin") - if pkga != "" { - // Always set PkgTargetRoot. It might be used when building in shared - // mode. - p.PkgTargetRoot = ctxt.joinPath(p.Root, pkgtargetroot) - - // Set the install target if applicable. - if !p.Goroot || (installgoroot.Value() == "all" && p.ImportPath != "unsafe" && p.ImportPath != "builtin") { - if p.Goroot { - installgoroot.IncNonDefault() - } - p.PkgObj = ctxt.joinPath(p.Root, pkga) - } - } - } - - // If it's a local import path, by the time we get here, we still haven't checked - // that p.Dir directory exists. This is the right time to do that check. - // We can't do it earlier, because we want to gather partial information for the - // non-nil *Package returned when an error occurs. - // We need to do this before we return early on FindOnly flag. - if IsLocalImport(path) && !ctxt.isDir(p.Dir) { - if ctxt.Compiler == "gccgo" && p.Goroot { - // gccgo has no sources for GOROOT packages. - return p, nil - } - - // package was not found - return p, fmt.Errorf("cannot find package %q in:\n\t%s", p.ImportPath, p.Dir) - } - - if mode&FindOnly != 0 { - return p, pkgerr - } - if binaryOnly && (mode&AllowBinary) != 0 { - return p, pkgerr - } - - if ctxt.Compiler == "gccgo" && p.Goroot { - // gccgo has no sources for GOROOT packages. - return p, nil - } - - dirs, err := ctxt.readDir(p.Dir) - if err != nil { - return p, err - } - - var badGoError error - badGoFiles := make(map[string]bool) - badGoFile := func(name string, err error) { - if badGoError == nil { - badGoError = err - } - if !badGoFiles[name] { - p.InvalidGoFiles = append(p.InvalidGoFiles, name) - badGoFiles[name] = true - } - } - - var Sfiles []string // files with ".S"(capital S)/.sx(capital s equivalent for case insensitive filesystems) - var firstFile, firstCommentFile string - embedPos := make(map[string][]token.Position) - testEmbedPos := make(map[string][]token.Position) - xTestEmbedPos := make(map[string][]token.Position) - importPos := make(map[string][]token.Position) - testImportPos := make(map[string][]token.Position) - xTestImportPos := make(map[string][]token.Position) - allTags := make(map[string]bool) - fset := token.NewFileSet() - for _, d := range dirs { - if d.IsDir() { - continue - } - if d.Type() == fs.ModeSymlink { - if ctxt.isDir(ctxt.joinPath(p.Dir, d.Name())) { - // Symlinks to directories are not source files. - continue - } - } - - name := d.Name() - ext := nameExt(name) - - info, err := ctxt.matchFile(p.Dir, name, allTags, &p.BinaryOnly, fset) - if err != nil && strings.HasSuffix(name, ".go") { - badGoFile(name, err) - continue - } - if info == nil { - if strings.HasPrefix(name, "_") || strings.HasPrefix(name, ".") { - // not due to build constraints - don't report - } else if ext == ".go" { - p.IgnoredGoFiles = append(p.IgnoredGoFiles, name) - } else if fileListForExt(p, ext) != nil { - p.IgnoredOtherFiles = append(p.IgnoredOtherFiles, name) - } - continue - } - - // Going to save the file. For non-Go files, can stop here. - switch ext { - case ".go": - // keep going - case ".S", ".sx": - // special case for cgo, handled at end - Sfiles = append(Sfiles, name) - continue - default: - if list := fileListForExt(p, ext); list != nil { - *list = append(*list, name) - } - continue - } - - data, filename := info.header, info.name - - if info.parseErr != nil { - badGoFile(name, info.parseErr) - // Fall through: we might still have a partial AST in info.parsed, - // and we want to list files with parse errors anyway. - } - - var pkg string - if info.parsed != nil { - pkg = info.parsed.Name.Name - if pkg == "documentation" { - p.IgnoredGoFiles = append(p.IgnoredGoFiles, name) - continue - } - } - - isTest := strings.HasSuffix(name, "_test.go") - isXTest := false - if isTest && strings.HasSuffix(pkg, "_test") && p.Name != pkg { - isXTest = true - pkg = pkg[:len(pkg)-len("_test")] - } - - if p.Name == "" { - p.Name = pkg - firstFile = name - } else if pkg != p.Name { - // TODO(#45999): The choice of p.Name is arbitrary based on file iteration - // order. Instead of resolving p.Name arbitrarily, we should clear out the - // existing name and mark the existing files as also invalid. - badGoFile(name, &MultiplePackageError{ - Dir: p.Dir, - Packages: []string{p.Name, pkg}, - Files: []string{firstFile, name}, - }) - } - // Grab the first package comment as docs, provided it is not from a test file. - if info.parsed != nil && info.parsed.Doc != nil && p.Doc == "" && !isTest && !isXTest { - p.Doc = doc.Synopsis(info.parsed.Doc.Text()) - } - - if mode&ImportComment != 0 { - qcom, line := findImportComment(data) - if line != 0 { - com, err := strconv.Unquote(qcom) - if err != nil { - badGoFile(name, fmt.Errorf("%s:%d: cannot parse import comment", filename, line)) - } else if p.ImportComment == "" { - p.ImportComment = com - firstCommentFile = name - } else if p.ImportComment != com { - badGoFile(name, fmt.Errorf("found import comments %q (%s) and %q (%s) in %s", p.ImportComment, firstCommentFile, com, name, p.Dir)) - } - } - } - - // Record imports and information about cgo. - isCgo := false - for _, imp := range info.imports { - if imp.path == "C" { - if isTest { - badGoFile(name, fmt.Errorf("use of cgo in test %s not supported", filename)) - continue - } - isCgo = true - if imp.doc != nil { - if err := ctxt.saveCgo(filename, p, imp.doc); err != nil { - badGoFile(name, err) - } - } - } - } - - var fileList *[]string - var importMap, embedMap map[string][]token.Position - var directives *[]Directive - switch { - case isCgo: - allTags["cgo"] = true - if ctxt.CgoEnabled { - fileList = &p.CgoFiles - importMap = importPos - embedMap = embedPos - directives = &p.Directives - } else { - // Ignore imports and embeds from cgo files if cgo is disabled. - fileList = &p.IgnoredGoFiles - } - case isXTest: - fileList = &p.XTestGoFiles - importMap = xTestImportPos - embedMap = xTestEmbedPos - directives = &p.XTestDirectives - case isTest: - fileList = &p.TestGoFiles - importMap = testImportPos - embedMap = testEmbedPos - directives = &p.TestDirectives - default: - fileList = &p.GoFiles - importMap = importPos - embedMap = embedPos - directives = &p.Directives - } - *fileList = append(*fileList, name) - if importMap != nil { - for _, imp := range info.imports { - importMap[imp.path] = append(importMap[imp.path], fset.Position(imp.pos)) - } - } - if embedMap != nil { - for _, emb := range info.embeds { - embedMap[emb.pattern] = append(embedMap[emb.pattern], emb.pos) - } - } - if directives != nil { - *directives = append(*directives, info.directives...) - } - } - - for tag := range allTags { - p.AllTags = append(p.AllTags, tag) - } - slices.Sort(p.AllTags) - - p.EmbedPatterns, p.EmbedPatternPos = cleanDecls(embedPos) - p.TestEmbedPatterns, p.TestEmbedPatternPos = cleanDecls(testEmbedPos) - p.XTestEmbedPatterns, p.XTestEmbedPatternPos = cleanDecls(xTestEmbedPos) - - p.Imports, p.ImportPos = cleanDecls(importPos) - p.TestImports, p.TestImportPos = cleanDecls(testImportPos) - p.XTestImports, p.XTestImportPos = cleanDecls(xTestImportPos) - - // add the .S/.sx files only if we are using cgo - // (which means gcc will compile them). - // The standard assemblers expect .s files. - if len(p.CgoFiles) > 0 { - p.SFiles = append(p.SFiles, Sfiles...) - slices.Sort(p.SFiles) - } else { - p.IgnoredOtherFiles = append(p.IgnoredOtherFiles, Sfiles...) - slices.Sort(p.IgnoredOtherFiles) - } - - if badGoError != nil { - return p, badGoError - } - if len(p.GoFiles)+len(p.CgoFiles)+len(p.TestGoFiles)+len(p.XTestGoFiles) == 0 { - return p, &NoGoError{p.Dir} - } - return p, pkgerr -} - -func fileListForExt(p *Package, ext string) *[]string { - switch ext { - case ".c": - return &p.CFiles - case ".cc", ".cpp", ".cxx": - return &p.CXXFiles - case ".m": - return &p.MFiles - case ".h", ".hh", ".hpp", ".hxx": - return &p.HFiles - case ".f", ".F", ".for", ".f90": - return &p.FFiles - case ".s", ".S", ".sx": - return &p.SFiles - case ".swig": - return &p.SwigFiles - case ".swigcxx": - return &p.SwigCXXFiles - case ".syso": - return &p.SysoFiles - } - return nil -} - -func uniq(list []string) []string { - if list == nil { - return nil - } - out := make([]string, len(list)) - copy(out, list) - slices.Sort(out) - uniq := out[:0] - for _, x := range out { - if len(uniq) == 0 || uniq[len(uniq)-1] != x { - uniq = append(uniq, x) - } - } - return uniq -} - -var errNoModules = errors.New("not using modules") - -// importGo checks whether it can use the go command to find the directory for path. -// If using the go command is not appropriate, importGo returns errNoModules. -// Otherwise, importGo tries using the go command and reports whether that succeeded. -// Using the go command lets build.Import and build.Context.Import find code -// in Go modules. In the long term we want tools to use go/packages (currently golang.org/x/tools/go/packages), -// which will also use the go command. -// Invoking the go command here is not very efficient in that it computes information -// about the requested package and all dependencies and then only reports about the requested package. -// Then we reinvoke it for every dependency. But this is still better than not working at all. -// See golang.org/issue/26504. -func (ctxt *Context) importGo(p *Package, path, srcDir string, mode ImportMode) error { - // To invoke the go command, - // we must not being doing special things like AllowBinary or IgnoreVendor, - // and all the file system callbacks must be nil (we're meant to use the local file system). - if mode&AllowBinary != 0 || mode&IgnoreVendor != 0 || - ctxt.JoinPath != nil || ctxt.SplitPathList != nil || ctxt.IsAbsPath != nil || ctxt.IsDir != nil || ctxt.HasSubdir != nil || ctxt.ReadDir != nil || ctxt.OpenFile != nil || !equal(ctxt.ToolTags, defaultToolTags) || !equal(ctxt.ReleaseTags, defaultReleaseTags) { - return errNoModules - } - - // If ctxt.GOROOT is not set, we don't know which go command to invoke, - // and even if we did we might return packages in GOROOT that we wouldn't otherwise find - // (because we don't know to search in 'go env GOROOT' otherwise). - if ctxt.GOROOT == "" { - return errNoModules - } - - // Predict whether module aware mode is enabled by checking the value of - // GO111MODULE and looking for a go.mod file in the source directory or - // one of its parents. Running 'go env GOMOD' in the source directory would - // give a canonical answer, but we'd prefer not to execute another command. - go111Module := os.Getenv("GO111MODULE") - switch go111Module { - case "off": - return errNoModules - default: // "", "on", "auto", anything else - // Maybe use modules. - } - - if srcDir != "" { - var absSrcDir string - if filepath.IsAbs(srcDir) { - absSrcDir = srcDir - } else if ctxt.Dir != "" { - return fmt.Errorf("go/build: Dir is non-empty, so relative srcDir is not allowed: %v", srcDir) - } else { - // Find the absolute source directory. hasSubdir does not handle - // relative paths (and can't because the callbacks don't support this). - var err error - absSrcDir, err = filepath.Abs(srcDir) - if err != nil { - return errNoModules - } - } - - // If the source directory is in GOROOT, then the in-process code works fine - // and we should keep using it. Moreover, the 'go list' approach below doesn't - // take standard-library vendoring into account and will fail. - if _, ok := ctxt.hasSubdir(filepath.Join(ctxt.GOROOT, "src"), absSrcDir); ok { - return errNoModules - } - } - - // For efficiency, if path is a standard library package, let the usual lookup code handle it. - if dir := ctxt.joinPath(ctxt.GOROOT, "src", path); ctxt.isDir(dir) { - return errNoModules - } - - // If GO111MODULE=auto, look to see if there is a go.mod. - // Since go1.13, it doesn't matter if we're inside GOPATH. - if go111Module == "auto" { - var ( - parent string - err error - ) - if ctxt.Dir == "" { - parent, err = os.Getwd() - if err != nil { - // A nonexistent working directory can't be in a module. - return errNoModules - } - } else { - parent, err = filepath.Abs(ctxt.Dir) - if err != nil { - // If the caller passed a bogus Dir explicitly, that's materially - // different from not having modules enabled. - return err - } - } - for { - if f, err := ctxt.openFile(ctxt.joinPath(parent, "go.mod")); err == nil { - buf := make([]byte, 100) - _, err := f.Read(buf) - f.Close() - if err == nil || err == io.EOF { - // go.mod exists and is readable (is a file, not a directory). - break - } - } - d := filepath.Dir(parent) - if len(d) >= len(parent) { - return errNoModules // reached top of file system, no go.mod - } - parent = d - } - } - - goCmd := filepath.Join(ctxt.GOROOT, "bin", "go") - cmd := exec.Command(goCmd, "list", "-e", "-compiler="+ctxt.Compiler, "-tags="+strings.Join(ctxt.BuildTags, ","), "-installsuffix="+ctxt.InstallSuffix, "-f={{.Dir}}\n{{.ImportPath}}\n{{.Root}}\n{{.Goroot}}\n{{if .Error}}{{.Error}}{{end}}\n", "--", path) - - if ctxt.Dir != "" { - cmd.Dir = ctxt.Dir - } - - var stdout, stderr strings.Builder - cmd.Stdout = &stdout - cmd.Stderr = &stderr - - cgo := "0" - if ctxt.CgoEnabled { - cgo = "1" - } - cmd.Env = append(cmd.Environ(), - "GOOS="+ctxt.GOOS, - "GOARCH="+ctxt.GOARCH, - "GOROOT="+ctxt.GOROOT, - "GOPATH="+ctxt.GOPATH, - "CGO_ENABLED="+cgo, - ) - - if err := cmd.Run(); err != nil { - return fmt.Errorf("go/build: go list %s: %v\n%s\n", path, err, stderr.String()) - } - - f := strings.SplitN(stdout.String(), "\n", 5) - if len(f) != 5 { - return fmt.Errorf("go/build: importGo %s: unexpected output:\n%s\n", path, stdout.String()) - } - dir := f[0] - errStr := strings.TrimSpace(f[4]) - if errStr != "" && dir == "" { - // If 'go list' could not locate the package (dir is empty), - // return the same error that 'go list' reported. - return errors.New(errStr) - } - - // If 'go list' did locate the package, ignore the error. - // It was probably related to loading source files, and we'll - // encounter it ourselves shortly if the FindOnly flag isn't set. - p.Dir = dir - p.ImportPath = f[1] - p.Root = f[2] - p.Goroot = f[3] == "true" - return nil -} - -func equal(x, y []string) bool { - if len(x) != len(y) { - return false - } - for i, xi := range x { - if xi != y[i] { - return false - } - } - return true -} - -// 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(ctxt *Context, dir string) bool { - ents, _ := ctxt.readDir(dir) - for _, ent := range ents { - if !ent.IsDir() && strings.HasSuffix(ent.Name(), ".go") { - return true - } - } - return false -} - -func findImportComment(data []byte) (s string, line int) { - // expect keyword package - word, data := parseWord(data) - if string(word) != "package" { - return "", 0 - } - - // expect package name - _, data = parseWord(data) - - // now ready for import comment, a // or /* */ comment - // beginning and ending on the current line. - for len(data) > 0 && (data[0] == ' ' || data[0] == '\t' || data[0] == '\r') { - data = data[1:] - } - - var comment []byte - switch { - case bytes.HasPrefix(data, slashSlash): - comment, _, _ = bytes.Cut(data[2:], newline) - case bytes.HasPrefix(data, slashStar): - var ok bool - comment, _, ok = bytes.Cut(data[2:], starSlash) - if !ok { - // malformed comment - return "", 0 - } - if bytes.Contains(comment, newline) { - return "", 0 - } - } - comment = bytes.TrimSpace(comment) - - // split comment into `import`, `"pkg"` - word, arg := parseWord(comment) - if string(word) != "import" { - return "", 0 - } - - line = 1 + bytes.Count(data[:cap(data)-cap(arg)], newline) - return strings.TrimSpace(string(arg)), line -} - -var ( - slashSlash = []byte("//") - slashStar = []byte("/*") - starSlash = []byte("*/") - newline = []byte("\n") -) - -// skipSpaceOrComment returns data with any leading spaces or comments removed. -func skipSpaceOrComment(data []byte) []byte { - for len(data) > 0 { - switch data[0] { - case ' ', '\t', '\r', '\n': - data = data[1:] - continue - case '/': - if bytes.HasPrefix(data, slashSlash) { - i := bytes.Index(data, newline) - if i < 0 { - return nil - } - data = data[i+1:] - continue - } - if bytes.HasPrefix(data, slashStar) { - data = data[2:] - i := bytes.Index(data, starSlash) - if i < 0 { - return nil - } - data = data[i+2:] - continue - } - } - break - } - return data -} - -// parseWord skips any leading spaces or comments in data -// and then parses the beginning of data as an identifier or keyword, -// returning that word and what remains after the word. -func parseWord(data []byte) (word, rest []byte) { - data = skipSpaceOrComment(data) - - // Parse past leading word characters. - rest = data - for { - r, size := utf8.DecodeRune(rest) - if unicode.IsLetter(r) || '0' <= r && r <= '9' || r == '_' { - rest = rest[size:] - continue - } - break - } - - word = data[:len(data)-len(rest)] - if len(word) == 0 { - return nil, nil - } - - return word, rest -} - -// MatchFile reports whether the file with the given name in the given directory -// matches the context and would be included in a [Package] created by [ImportDir] -// of that directory. -// -// MatchFile considers the name of the file and may use ctxt.OpenFile to -// read some or all of the file's content. -func (ctxt *Context) MatchFile(dir, name string) (match bool, err error) { - info, err := ctxt.matchFile(dir, name, nil, nil, nil) - return info != nil, err -} - -var dummyPkg Package - -// fileInfo records information learned about a file included in a build. -type fileInfo struct { - name string // full name including dir - header []byte - fset *token.FileSet - parsed *ast.File - parseErr error - imports []fileImport - embeds []fileEmbed - directives []Directive -} - -type fileImport struct { - path string - pos token.Pos - doc *ast.CommentGroup -} - -type fileEmbed struct { - pattern string - pos token.Position -} - -// matchFile determines whether the file with the given name in the given directory -// should be included in the package being constructed. -// If the file should be included, matchFile returns a non-nil *fileInfo (and a nil error). -// Non-nil errors are reserved for unexpected problems. -// -// If name denotes a Go program, matchFile reads until the end of the -// imports and returns that section of the file in the fileInfo's header field, -// even though it only considers text until the first non-comment -// for go:build lines. -// -// If allTags is non-nil, matchFile records any encountered build tag -// by setting allTags[tag] = true. -func (ctxt *Context) matchFile(dir, name string, allTags map[string]bool, binaryOnly *bool, fset *token.FileSet) (*fileInfo, error) { - if strings.HasPrefix(name, "_") || - strings.HasPrefix(name, ".") { - return nil, nil - } - - i := strings.LastIndex(name, ".") - if i < 0 { - i = len(name) - } - ext := name[i:] - - if ext != ".go" && fileListForExt(&dummyPkg, ext) == nil { - // skip - return nil, nil - } - - if !ctxt.goodOSArchFile(name, allTags) && !ctxt.UseAllFiles { - return nil, nil - } - - info := &fileInfo{name: ctxt.joinPath(dir, name), fset: fset} - if ext == ".syso" { - // binary, no reading - return info, nil - } - - f, err := ctxt.openFile(info.name) - if err != nil { - return nil, err - } - - if strings.HasSuffix(name, ".go") { - err = readGoInfo(f, info) - if strings.HasSuffix(name, "_test.go") { - binaryOnly = nil // ignore //go:binary-only-package comments in _test.go files - } - } else { - binaryOnly = nil // ignore //go:binary-only-package comments in non-Go sources - info.header, err = readComments(f) - } - f.Close() - if err != nil { - return info, fmt.Errorf("read %s: %v", info.name, err) - } - - // Look for go:build comments to accept or reject the file. - ok, sawBinaryOnly, err := ctxt.shouldBuild(info.header, allTags) - if err != nil { - return nil, fmt.Errorf("%s: %v", name, err) - } - if !ok && !ctxt.UseAllFiles { - return nil, nil - } - - if binaryOnly != nil && sawBinaryOnly { - *binaryOnly = true - } - - return info, nil -} - -func cleanDecls(m map[string][]token.Position) ([]string, map[string][]token.Position) { - all := make([]string, 0, len(m)) - for path := range m { - all = append(all, path) - } - slices.Sort(all) - return all, m -} - -// Import is shorthand for Default.Import. -func Import(path, srcDir string, mode ImportMode) (*Package, error) { - return Default.Import(path, srcDir, mode) -} - -// ImportDir is shorthand for Default.ImportDir. -func ImportDir(dir string, mode ImportMode) (*Package, error) { - return Default.ImportDir(dir, mode) -} - -var ( - plusBuild = []byte("+build") - - goBuildComment = []byte("//go:build") - - errMultipleGoBuild = errors.New("multiple //go:build comments") -) - -func isGoBuildComment(line []byte) bool { - if !bytes.HasPrefix(line, goBuildComment) { - return false - } - line = bytes.TrimSpace(line) - rest := line[len(goBuildComment):] - return len(rest) == 0 || len(bytes.TrimSpace(rest)) < len(rest) -} - -// Special comment denoting a binary-only package. -// See https://golang.org/design/2775-binary-only-packages -// for more about the design of binary-only packages. -var binaryOnlyComment = []byte("//go:binary-only-package") - -// shouldBuild reports whether it is okay to use this file, -// The rule is that in the file's leading run of // comments -// and blank lines, which must be followed by a blank line -// (to avoid including a Go package clause doc comment), -// lines beginning with '//go:build' are taken as build directives. -// -// The file is accepted only if each such line lists something -// matching the file. For example: -// -// //go:build windows linux -// -// marks the file as applicable only on Windows and Linux. -// -// For each build tag it consults, shouldBuild sets allTags[tag] = true. -// -// shouldBuild reports whether the file should be built -// and whether a //go:binary-only-package comment was found. -func (ctxt *Context) shouldBuild(content []byte, allTags map[string]bool) (shouldBuild, binaryOnly bool, err error) { - // Identify leading run of // comments and blank lines, - // which must be followed by a blank line. - // Also identify any //go:build comments. - content, goBuild, sawBinaryOnly, err := parseFileHeader(content) - if err != nil { - return false, false, err - } - - // If //go:build line is present, it controls. - // Otherwise fall back to +build processing. - switch { - case goBuild != nil: - x, err := constraint.Parse(string(goBuild)) - if err != nil { - return false, false, fmt.Errorf("parsing //go:build line: %v", err) - } - shouldBuild = ctxt.eval(x, allTags) - - default: - shouldBuild = true - p := content - for len(p) > 0 { - line := p - if i := bytes.IndexByte(line, '\n'); i >= 0 { - line, p = line[:i], p[i+1:] - } else { - p = p[len(p):] - } - line = bytes.TrimSpace(line) - if !bytes.HasPrefix(line, slashSlash) || !bytes.Contains(line, plusBuild) { - continue - } - text := string(line) - if !constraint.IsPlusBuild(text) { - continue - } - if x, err := constraint.Parse(text); err == nil { - if !ctxt.eval(x, allTags) { - shouldBuild = false - } - } - } - } - - return shouldBuild, sawBinaryOnly, nil -} - -// parseFileHeader should be an internal detail, -// but widely used packages access it using linkname. -// Notable members of the hall of shame include: -// - github.com/bazelbuild/bazel-gazelle -// -// Do not remove or change the type signature. -// See go.dev/issue/67401. -// -//go:linkname parseFileHeader -func parseFileHeader(content []byte) (trimmed, goBuild []byte, sawBinaryOnly bool, err error) { - end := 0 - p := content - ended := false // found non-blank, non-// line, so stopped accepting //go:build lines - inSlashStar := false // in /* */ comment - -Lines: - for len(p) > 0 { - line := p - if i := bytes.IndexByte(line, '\n'); i >= 0 { - line, p = line[:i], p[i+1:] - } else { - p = p[len(p):] - } - line = bytes.TrimSpace(line) - if len(line) == 0 && !ended { // Blank line - // Remember position of most recent blank line. - // When we find the first non-blank, non-// line, - // this "end" position marks the latest file position - // where a //go:build line can appear. - // (It must appear _before_ a blank line before the non-blank, non-// line. - // Yes, that's confusing, which is part of why we moved to //go:build lines.) - // Note that ended==false here means that inSlashStar==false, - // since seeing a /* would have set ended==true. - end = len(content) - len(p) - continue Lines - } - if !bytes.HasPrefix(line, slashSlash) { // Not comment line - ended = true - } - - if !inSlashStar && isGoBuildComment(line) { - if goBuild != nil { - return nil, nil, false, errMultipleGoBuild - } - goBuild = line - } - if !inSlashStar && bytes.Equal(line, binaryOnlyComment) { - sawBinaryOnly = true - } - - Comments: - for len(line) > 0 { - if inSlashStar { - if i := bytes.Index(line, starSlash); i >= 0 { - inSlashStar = false - line = bytes.TrimSpace(line[i+len(starSlash):]) - continue Comments - } - continue Lines - } - if bytes.HasPrefix(line, slashSlash) { - continue Lines - } - if bytes.HasPrefix(line, slashStar) { - inSlashStar = true - line = bytes.TrimSpace(line[len(slashStar):]) - continue Comments - } - // Found non-comment text. - break Lines - } - } - - return content[:end], goBuild, sawBinaryOnly, nil -} - -// saveCgo saves the information from the #cgo lines in the import "C" comment. -// These lines set CFLAGS, CPPFLAGS, CXXFLAGS and LDFLAGS and pkg-config directives -// that affect the way cgo's C code is built. -func (ctxt *Context) saveCgo(filename string, di *Package, cg *ast.CommentGroup) error { - text := cg.Text() - for _, line := range strings.Split(text, "\n") { - orig := line - - // Line is - // #cgo [GOOS/GOARCH...] LDFLAGS: stuff - // - line = strings.TrimSpace(line) - if len(line) < 5 || line[:4] != "#cgo" || (line[4] != ' ' && line[4] != '\t') { - continue - } - - // #cgo (nocallback|noescape) - if fields := strings.Fields(line); len(fields) == 3 && (fields[1] == "nocallback" || fields[1] == "noescape") { - continue - } - - // Split at colon. - line, argstr, ok := strings.Cut(strings.TrimSpace(line[4:]), ":") - if !ok { - return fmt.Errorf("%s: invalid #cgo line: %s", filename, orig) - } - - // Parse GOOS/GOARCH stuff. - f := strings.Fields(line) - if len(f) < 1 { - return fmt.Errorf("%s: invalid #cgo line: %s", filename, orig) - } - - cond, verb := f[:len(f)-1], f[len(f)-1] - if len(cond) > 0 { - ok := false - for _, c := range cond { - if ctxt.matchAuto(c, nil) { - ok = true - break - } - } - if !ok { - continue - } - } - - args, err := splitQuoted(argstr) - if err != nil { - return fmt.Errorf("%s: invalid #cgo line: %s", filename, orig) - } - for i, arg := range args { - if arg, ok = expandSrcDir(arg, di.Dir); !ok { - return fmt.Errorf("%s: malformed #cgo argument: %s", filename, arg) - } - args[i] = arg - } - - switch verb { - case "CFLAGS", "CPPFLAGS", "CXXFLAGS", "FFLAGS", "LDFLAGS": - // Change relative paths to absolute. - ctxt.makePathsAbsolute(args, di.Dir) - } - - switch verb { - case "CFLAGS": - di.CgoCFLAGS = append(di.CgoCFLAGS, args...) - case "CPPFLAGS": - di.CgoCPPFLAGS = append(di.CgoCPPFLAGS, args...) - case "CXXFLAGS": - di.CgoCXXFLAGS = append(di.CgoCXXFLAGS, args...) - case "FFLAGS": - di.CgoFFLAGS = append(di.CgoFFLAGS, args...) - case "LDFLAGS": - di.CgoLDFLAGS = append(di.CgoLDFLAGS, args...) - case "pkg-config": - di.CgoPkgConfig = append(di.CgoPkgConfig, args...) - default: - return fmt.Errorf("%s: invalid #cgo verb: %s", filename, orig) - } - } - return nil -} - -// expandSrcDir expands any occurrence of ${SRCDIR}, making sure -// the result is safe for the shell. -func expandSrcDir(str string, srcdir string) (string, bool) { - // "\" delimited paths cause safeCgoName to fail - // so convert native paths with a different delimiter - // to "/" before starting (eg: on windows). - srcdir = filepath.ToSlash(srcdir) - - chunks := strings.Split(str, "${SRCDIR}") - if len(chunks) < 2 { - return str, safeCgoName(str) - } - ok := true - for _, chunk := range chunks { - ok = ok && (chunk == "" || safeCgoName(chunk)) - } - ok = ok && (srcdir == "" || safeCgoName(srcdir)) - res := strings.Join(chunks, srcdir) - return res, ok && res != "" -} - -// makePathsAbsolute looks for compiler options that take paths and -// makes them absolute. We do this because through the 1.8 release we -// ran the compiler in the package directory, so any relative -I or -L -// options would be relative to that directory. In 1.9 we changed to -// running the compiler in the build directory, to get consistent -// build results (issue #19964). To keep builds working, we change any -// relative -I or -L options to be absolute. -// -// Using filepath.IsAbs and filepath.Join here means the results will be -// different on different systems, but that's OK: -I and -L options are -// inherently system-dependent. -func (ctxt *Context) makePathsAbsolute(args []string, srcDir string) { - nextPath := false - for i, arg := range args { - if nextPath { - if !filepath.IsAbs(arg) { - args[i] = filepath.Join(srcDir, arg) - } - nextPath = false - } else if strings.HasPrefix(arg, "-I") || strings.HasPrefix(arg, "-L") { - if len(arg) == 2 { - nextPath = true - } else { - if !filepath.IsAbs(arg[2:]) { - args[i] = arg[:2] + filepath.Join(srcDir, arg[2:]) - } - } - } - } -} - -// NOTE: $ is not safe for the shell, but it is allowed here because of linker options like -Wl,$ORIGIN. -// We never pass these arguments to a shell (just to programs we construct argv for), so this should be okay. -// See golang.org/issue/6038. -// The @ is for OS X. See golang.org/issue/13720. -// The % is for Jenkins. See golang.org/issue/16959. -// The ! is because module paths may use them. See golang.org/issue/26716. -// The ~ and ^ are for sr.ht. See golang.org/issue/32260. -const safeString = "+-.,/0123456789=ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz:$@%! ~^" - -func safeCgoName(s string) bool { - if s == "" { - return false - } - for i := 0; i < len(s); i++ { - if c := s[i]; c < utf8.RuneSelf && strings.IndexByte(safeString, c) < 0 { - return false - } - } - return true -} - -// splitQuoted splits the string s around each instance of one or more consecutive -// white space characters while taking into account quotes and escaping, and -// returns an array of substrings of s or an empty list if s contains only white space. -// Single quotes and double quotes are recognized to prevent splitting within the -// quoted region, and are removed from the resulting substrings. If a quote in s -// isn't closed err will be set and r will have the unclosed argument as the -// last element. The backslash is used for escaping. -// -// For example, the following string: -// -// a b:"c d" 'e''f' "g\"" -// -// Would be parsed as: -// -// []string{"a", "b:c d", "ef", `g"`} -func splitQuoted(s string) (r []string, err error) { - var args []string - arg := make([]rune, len(s)) - escaped := false - quoted := false - quote := '\x00' - i := 0 - for _, rune := range s { - switch { - case escaped: - escaped = false - case rune == '\\': - escaped = true - continue - case quote != '\x00': - if rune == quote { - quote = '\x00' - continue - } - case rune == '"' || rune == '\'': - quoted = true - quote = rune - continue - case unicode.IsSpace(rune): - if quoted || i > 0 { - quoted = false - args = append(args, string(arg[:i])) - i = 0 - } - continue - } - arg[i] = rune - i++ - } - if quoted || i > 0 { - args = append(args, string(arg[:i])) - } - if quote != 0 { - err = errors.New("unclosed quote") - } else if escaped { - err = errors.New("unfinished escaping") - } - return args, err -} - -// matchAuto interprets text as either a +build or //go:build expression (whichever works), -// reporting whether the expression matches the build context. -// -// matchAuto is only used for testing of tag evaluation -// and in #cgo lines, which accept either syntax. -func (ctxt *Context) matchAuto(text string, allTags map[string]bool) bool { - if strings.ContainsAny(text, "&|()") { - text = "//go:build " + text - } else { - text = "// +build " + text - } - x, err := constraint.Parse(text) - if err != nil { - return false - } - return ctxt.eval(x, allTags) -} - -func (ctxt *Context) eval(x constraint.Expr, allTags map[string]bool) bool { - return x.Eval(func(tag string) bool { return ctxt.matchTag(tag, allTags) }) -} - -// matchTag reports whether the name is one of: -// -// cgo (if cgo is enabled) -// $GOOS -// $GOARCH -// ctxt.Compiler -// linux (if GOOS = android) -// solaris (if GOOS = illumos) -// darwin (if GOOS = ios) -// unix (if this is a Unix GOOS) -// boringcrypto (if GOEXPERIMENT=boringcrypto is enabled) -// tag (if tag is listed in ctxt.BuildTags, ctxt.ToolTags, or ctxt.ReleaseTags) -// -// It records all consulted tags in allTags. -func (ctxt *Context) matchTag(name string, allTags map[string]bool) bool { - if allTags != nil { - allTags[name] = true - } - - // special tags - if ctxt.CgoEnabled && name == "cgo" { - return true - } - if name == ctxt.GOOS || name == ctxt.GOARCH || name == ctxt.Compiler { - return true - } - if ctxt.GOOS == "android" && name == "linux" { - return true - } - if ctxt.GOOS == "illumos" && name == "solaris" { - return true - } - if ctxt.GOOS == "ios" && name == "darwin" { - return true - } - if name == "unix" && syslist.UnixOS[ctxt.GOOS] { - return true - } - if name == "boringcrypto" { - name = "goexperiment.boringcrypto" // boringcrypto is an old name for goexperiment.boringcrypto - } - - // other tags - for _, tag := range ctxt.BuildTags { - if tag == name { - return true - } - } - for _, tag := range ctxt.ToolTags { - if tag == name { - return true - } - } - for _, tag := range ctxt.ReleaseTags { - if tag == name { - return true - } - } - - return false -} - -// goodOSArchFile returns false if the name contains a $GOOS or $GOARCH -// suffix which does not match the current system. -// The recognized name formats are: -// -// name_$(GOOS).* -// name_$(GOARCH).* -// name_$(GOOS)_$(GOARCH).* -// name_$(GOOS)_test.* -// name_$(GOARCH)_test.* -// name_$(GOOS)_$(GOARCH)_test.* -// -// Exceptions: -// if GOOS=android, then files with GOOS=linux are also matched. -// if GOOS=illumos, then files with GOOS=solaris are also matched. -// if GOOS=ios, then files with GOOS=darwin are also matched. -func (ctxt *Context) goodOSArchFile(name string, allTags map[string]bool) bool { - name, _, _ = strings.Cut(name, ".") - - // Before Go 1.4, a file called "linux.go" would be equivalent to having a - // build tag "linux" in that file. For Go 1.4 and beyond, we require this - // auto-tagging to apply only to files with a non-empty prefix, so - // "foo_linux.go" is tagged but "linux.go" is not. This allows new operating - // systems, such as android, to arrive without breaking existing code with - // innocuous source code in "android.go". The easiest fix: cut everything - // in the name before the initial _. - i := strings.Index(name, "_") - if i < 0 { - return true - } - name = name[i:] // ignore everything before first _ - - l := strings.Split(name, "_") - if n := len(l); n > 0 && l[n-1] == "test" { - l = l[:n-1] - } - n := len(l) - if n >= 2 && syslist.KnownOS[l[n-2]] && syslist.KnownArch[l[n-1]] { - if allTags != nil { - // In case we short-circuit on l[n-1]. - allTags[l[n-2]] = true - } - return ctxt.matchTag(l[n-1], allTags) && ctxt.matchTag(l[n-2], allTags) - } - if n >= 1 && (syslist.KnownOS[l[n-1]] || syslist.KnownArch[l[n-1]]) { - return ctxt.matchTag(l[n-1], allTags) - } - return true -} - -// ToolDir is the directory containing build tools. -var ToolDir = getToolDir() - -// IsLocalImport reports whether the import path is -// a local import path, like ".", "..", "./foo", or "../foo". -func IsLocalImport(path string) bool { - return path == "." || path == ".." || - strings.HasPrefix(path, "./") || strings.HasPrefix(path, "../") -} - -// ArchChar returns "?" and an error. -// In earlier versions of Go, the returned string was used to derive -// the compiler and linker tool names, the default object file suffix, -// and the default linker output name. As of Go 1.5, those strings -// no longer vary by architecture; they are compile, link, .o, and a.out, respectively. -func ArchChar(goarch string) (string, error) { - return "?", errors.New("architecture letter no longer used") +func defaultGOPATH() string { + env := "HOME" + if runtime.GOOS == "windows" { + env = "USERPROFILE" + } else if runtime.GOOS == "plan9" { + env = "home" + } + if home := os.Getenv(env); home != "" { + def := filepath.Join(home, "go") + if filepath.Clean(def) == filepath.Clean(runtime.GOROOT()) { + return "" + } + return def + } + return "" }