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-rw-r--r--libgo/go/cmd/go/internal/module/module.go632
1 files changed, 0 insertions, 632 deletions
diff --git a/libgo/go/cmd/go/internal/module/module.go b/libgo/go/cmd/go/internal/module/module.go
deleted file mode 100644
index 3e0baba15b3..00000000000
--- a/libgo/go/cmd/go/internal/module/module.go
+++ /dev/null
@@ -1,632 +0,0 @@
-// Copyright 2018 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 module defines the module.Version type
-// along with support code.
-package module
-
-// IMPORTANT NOTE
-//
-// This file essentially defines the set of valid import paths for the go command.
-// There are many subtle considerations, including Unicode ambiguity,
-// security, network, and file system representations.
-//
-// This file also defines the set of valid module path and version combinations,
-// another topic with many subtle considerations.
-//
-// Changes to the semantics in this file require approval from rsc.
-
-import (
- "errors"
- "fmt"
- "sort"
- "strings"
- "unicode"
- "unicode/utf8"
-
- "cmd/go/internal/semver"
-)
-
-// A Version is defined by a module path and version pair.
-type Version struct {
- Path string
-
- // Version is usually a semantic version in canonical form.
- // There are two exceptions to this general rule.
- // First, the top-level target of a build has no specific version
- // and uses Version = "".
- // Second, during MVS calculations the version "none" is used
- // to represent the decision to take no version of a given module.
- Version string `json:",omitempty"`
-}
-
-// A ModuleError indicates an error specific to a module.
-type ModuleError struct {
- Path string
- Version string
- Err error
-}
-
-// VersionError returns a ModuleError derived from a Version and error.
-func VersionError(v Version, err error) error {
- return &ModuleError{
- Path: v.Path,
- Version: v.Version,
- Err: err,
- }
-}
-
-func (e *ModuleError) Error() string {
- if v, ok := e.Err.(*InvalidVersionError); ok {
- return fmt.Sprintf("%s@%s: invalid %s: %v", e.Path, v.Version, v.noun(), v.Err)
- }
- if e.Version != "" {
- return fmt.Sprintf("%s@%s: %v", e.Path, e.Version, e.Err)
- }
- return fmt.Sprintf("module %s: %v", e.Path, e.Err)
-}
-
-func (e *ModuleError) Unwrap() error { return e.Err }
-
-// An InvalidVersionError indicates an error specific to a version, with the
-// module path unknown or specified externally.
-//
-// A ModuleError may wrap an InvalidVersionError, but an InvalidVersionError
-// must not wrap a ModuleError.
-type InvalidVersionError struct {
- Version string
- Pseudo bool
- Err error
-}
-
-// noun returns either "version" or "pseudo-version", depending on whether
-// e.Version is a pseudo-version.
-func (e *InvalidVersionError) noun() string {
- if e.Pseudo {
- return "pseudo-version"
- }
- return "version"
-}
-
-func (e *InvalidVersionError) Error() string {
- return fmt.Sprintf("%s %q invalid: %s", e.noun(), e.Version, e.Err)
-}
-
-func (e *InvalidVersionError) Unwrap() error { return e.Err }
-
-// Check checks that a given module path, version pair is valid.
-// In addition to the path being a valid module path
-// and the version being a valid semantic version,
-// the two must correspond.
-// For example, the path "yaml/v2" only corresponds to
-// semantic versions beginning with "v2.".
-func Check(path, version string) error {
- if err := CheckPath(path); err != nil {
- return err
- }
- if !semver.IsValid(version) {
- return &ModuleError{
- Path: path,
- Err: &InvalidVersionError{Version: version, Err: errors.New("not a semantic version")},
- }
- }
- _, pathMajor, _ := SplitPathVersion(path)
- if err := MatchPathMajor(version, pathMajor); err != nil {
- return &ModuleError{Path: path, Err: err}
- }
- return nil
-}
-
-// firstPathOK reports whether r can appear in the first element of a module path.
-// The first element of the path must be an LDH domain name, at least for now.
-// To avoid case ambiguity, the domain name must be entirely lower case.
-func firstPathOK(r rune) bool {
- return r == '-' || r == '.' ||
- '0' <= r && r <= '9' ||
- 'a' <= r && r <= 'z'
-}
-
-// pathOK reports whether r can appear in an import path element.
-// Paths can be ASCII letters, ASCII digits, and limited ASCII punctuation: + - . _ and ~.
-// This matches what "go get" has historically recognized in import paths.
-// TODO(rsc): We would like to allow Unicode letters, but that requires additional
-// care in the safe encoding (see note below).
-func pathOK(r rune) bool {
- if r < utf8.RuneSelf {
- return r == '+' || r == '-' || r == '.' || r == '_' || r == '~' ||
- '0' <= r && r <= '9' ||
- 'A' <= r && r <= 'Z' ||
- 'a' <= r && r <= 'z'
- }
- return false
-}
-
-// fileNameOK reports whether r can appear in a file name.
-// For now we allow all Unicode letters but otherwise limit to pathOK plus a few more punctuation characters.
-// If we expand the set of allowed characters here, we have to
-// work harder at detecting potential case-folding and normalization collisions.
-// See note about "safe encoding" below.
-func fileNameOK(r rune) bool {
- if r < utf8.RuneSelf {
- // Entire set of ASCII punctuation, from which we remove characters:
- // ! " # $ % & ' ( ) * + , - . / : ; < = > ? @ [ \ ] ^ _ ` { | } ~
- // We disallow some shell special characters: " ' * < > ? ` |
- // (Note that some of those are disallowed by the Windows file system as well.)
- // We also disallow path separators / : and \ (fileNameOK is only called on path element characters).
- // We allow spaces (U+0020) in file names.
- const allowed = "!#$%&()+,-.=@[]^_{}~ "
- if '0' <= r && r <= '9' || 'A' <= r && r <= 'Z' || 'a' <= r && r <= 'z' {
- return true
- }
- for i := 0; i < len(allowed); i++ {
- if rune(allowed[i]) == r {
- return true
- }
- }
- return false
- }
- // It may be OK to add more ASCII punctuation here, but only carefully.
- // For example Windows disallows < > \, and macOS disallows :, so we must not allow those.
- return unicode.IsLetter(r)
-}
-
-// CheckPath checks that a module path is valid.
-func CheckPath(path string) error {
- if err := checkPath(path, false); err != nil {
- return fmt.Errorf("malformed module path %q: %v", path, err)
- }
- i := strings.Index(path, "/")
- if i < 0 {
- i = len(path)
- }
- if i == 0 {
- return fmt.Errorf("malformed module path %q: leading slash", path)
- }
- if !strings.Contains(path[:i], ".") {
- return fmt.Errorf("malformed module path %q: missing dot in first path element", path)
- }
- if path[0] == '-' {
- return fmt.Errorf("malformed module path %q: leading dash in first path element", path)
- }
- for _, r := range path[:i] {
- if !firstPathOK(r) {
- return fmt.Errorf("malformed module path %q: invalid char %q in first path element", path, r)
- }
- }
- if _, _, ok := SplitPathVersion(path); !ok {
- return fmt.Errorf("malformed module path %q: invalid version", path)
- }
- return nil
-}
-
-// CheckImportPath checks that an import path is valid.
-func CheckImportPath(path string) error {
- if err := checkPath(path, false); err != nil {
- return fmt.Errorf("malformed import path %q: %v", path, err)
- }
- return nil
-}
-
-// checkPath checks that a general path is valid.
-// It returns an error describing why but not mentioning path.
-// Because these checks apply to both module paths and import paths,
-// the caller is expected to add the "malformed ___ path %q: " prefix.
-// fileName indicates whether the final element of the path is a file name
-// (as opposed to a directory name).
-func checkPath(path string, fileName bool) error {
- if !utf8.ValidString(path) {
- return fmt.Errorf("invalid UTF-8")
- }
- if path == "" {
- return fmt.Errorf("empty string")
- }
- if path[0] == '-' {
- return fmt.Errorf("leading dash")
- }
- if strings.Contains(path, "..") {
- return fmt.Errorf("double dot")
- }
- if strings.Contains(path, "//") {
- return fmt.Errorf("double slash")
- }
- if path[len(path)-1] == '/' {
- return fmt.Errorf("trailing slash")
- }
- elemStart := 0
- for i, r := range path {
- if r == '/' {
- if err := checkElem(path[elemStart:i], fileName); err != nil {
- return err
- }
- elemStart = i + 1
- }
- }
- if err := checkElem(path[elemStart:], fileName); err != nil {
- return err
- }
- return nil
-}
-
-// checkElem checks whether an individual path element is valid.
-// fileName indicates whether the element is a file name (not a directory name).
-func checkElem(elem string, fileName bool) error {
- if elem == "" {
- return fmt.Errorf("empty path element")
- }
- if strings.Count(elem, ".") == len(elem) {
- return fmt.Errorf("invalid path element %q", elem)
- }
- if elem[0] == '.' && !fileName {
- return fmt.Errorf("leading dot in path element")
- }
- if elem[len(elem)-1] == '.' {
- return fmt.Errorf("trailing dot in path element")
- }
- charOK := pathOK
- if fileName {
- charOK = fileNameOK
- }
- for _, r := range elem {
- if !charOK(r) {
- return fmt.Errorf("invalid char %q", r)
- }
- }
-
- // Windows disallows a bunch of path elements, sadly.
- // See https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file
- short := elem
- if i := strings.Index(short, "."); i >= 0 {
- short = short[:i]
- }
- for _, bad := range badWindowsNames {
- if strings.EqualFold(bad, short) {
- return fmt.Errorf("%q disallowed as path element component on Windows", short)
- }
- }
- return nil
-}
-
-// CheckFilePath checks whether a slash-separated file path is valid.
-func CheckFilePath(path string) error {
- if err := checkPath(path, true); err != nil {
- return fmt.Errorf("malformed file path %q: %v", path, err)
- }
- return nil
-}
-
-// badWindowsNames are the reserved file path elements on Windows.
-// See https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file
-var badWindowsNames = []string{
- "CON",
- "PRN",
- "AUX",
- "NUL",
- "COM1",
- "COM2",
- "COM3",
- "COM4",
- "COM5",
- "COM6",
- "COM7",
- "COM8",
- "COM9",
- "LPT1",
- "LPT2",
- "LPT3",
- "LPT4",
- "LPT5",
- "LPT6",
- "LPT7",
- "LPT8",
- "LPT9",
-}
-
-// SplitPathVersion returns prefix and major version such that prefix+pathMajor == path
-// and version is either empty or "/vN" for N >= 2.
-// As a special case, gopkg.in paths are recognized directly;
-// they require ".vN" instead of "/vN", and for all N, not just N >= 2.
-func SplitPathVersion(path string) (prefix, pathMajor string, ok bool) {
- if strings.HasPrefix(path, "gopkg.in/") {
- return splitGopkgIn(path)
- }
-
- i := len(path)
- dot := false
- for i > 0 && ('0' <= path[i-1] && path[i-1] <= '9' || path[i-1] == '.') {
- if path[i-1] == '.' {
- dot = true
- }
- i--
- }
- if i <= 1 || i == len(path) || path[i-1] != 'v' || path[i-2] != '/' {
- return path, "", true
- }
- prefix, pathMajor = path[:i-2], path[i-2:]
- if dot || len(pathMajor) <= 2 || pathMajor[2] == '0' || pathMajor == "/v1" {
- return path, "", false
- }
- return prefix, pathMajor, true
-}
-
-// splitGopkgIn is like SplitPathVersion but only for gopkg.in paths.
-func splitGopkgIn(path string) (prefix, pathMajor string, ok bool) {
- if !strings.HasPrefix(path, "gopkg.in/") {
- return path, "", false
- }
- i := len(path)
- if strings.HasSuffix(path, "-unstable") {
- i -= len("-unstable")
- }
- for i > 0 && ('0' <= path[i-1] && path[i-1] <= '9') {
- i--
- }
- if i <= 1 || path[i-1] != 'v' || path[i-2] != '.' {
- // All gopkg.in paths must end in vN for some N.
- return path, "", false
- }
- prefix, pathMajor = path[:i-2], path[i-2:]
- if len(pathMajor) <= 2 || pathMajor[2] == '0' && pathMajor != ".v0" {
- return path, "", false
- }
- return prefix, pathMajor, true
-}
-
-// MatchPathMajor returns a non-nil error if the semantic version v
-// does not match the path major version pathMajor.
-func MatchPathMajor(v, pathMajor string) error {
- if strings.HasPrefix(pathMajor, ".v") && strings.HasSuffix(pathMajor, "-unstable") {
- pathMajor = strings.TrimSuffix(pathMajor, "-unstable")
- }
- if strings.HasPrefix(v, "v0.0.0-") && pathMajor == ".v1" {
- // Allow old bug in pseudo-versions that generated v0.0.0- pseudoversion for gopkg .v1.
- // For example, gopkg.in/yaml.v2@v2.2.1's go.mod requires gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405.
- return nil
- }
- m := semver.Major(v)
- if pathMajor == "" {
- if m == "v0" || m == "v1" || semver.Build(v) == "+incompatible" {
- return nil
- }
- pathMajor = "v0 or v1"
- } else if pathMajor[0] == '/' || pathMajor[0] == '.' {
- if m == pathMajor[1:] {
- return nil
- }
- pathMajor = pathMajor[1:]
- }
- return &InvalidVersionError{
- Version: v,
- Err: fmt.Errorf("should be %s, not %s", pathMajor, semver.Major(v)),
- }
-}
-
-// PathMajorPrefix returns the major-version tag prefix implied by pathMajor.
-// An empty PathMajorPrefix allows either v0 or v1.
-//
-// Note that MatchPathMajor may accept some versions that do not actually begin
-// with this prefix: namely, it accepts a 'v0.0.0-' prefix for a '.v1'
-// pathMajor, even though that pathMajor implies 'v1' tagging.
-func PathMajorPrefix(pathMajor string) string {
- if pathMajor == "" {
- return ""
- }
- if pathMajor[0] != '/' && pathMajor[0] != '.' {
- panic("pathMajor suffix " + pathMajor + " passed to PathMajorPrefix lacks separator")
- }
- if strings.HasPrefix(pathMajor, ".v") && strings.HasSuffix(pathMajor, "-unstable") {
- pathMajor = strings.TrimSuffix(pathMajor, "-unstable")
- }
- m := pathMajor[1:]
- if m != semver.Major(m) {
- panic("pathMajor suffix " + pathMajor + "passed to PathMajorPrefix is not a valid major version")
- }
- return m
-}
-
-// CanonicalVersion returns the canonical form of the version string v.
-// It is the same as semver.Canonical(v) except that it preserves the special build suffix "+incompatible".
-func CanonicalVersion(v string) string {
- cv := semver.Canonical(v)
- if semver.Build(v) == "+incompatible" {
- cv += "+incompatible"
- }
- return cv
-}
-
-// Sort sorts the list by Path, breaking ties by comparing Versions.
-func Sort(list []Version) {
- sort.Slice(list, func(i, j int) bool {
- mi := list[i]
- mj := list[j]
- if mi.Path != mj.Path {
- return mi.Path < mj.Path
- }
- // To help go.sum formatting, allow version/file.
- // Compare semver prefix by semver rules,
- // file by string order.
- vi := mi.Version
- vj := mj.Version
- var fi, fj string
- if k := strings.Index(vi, "/"); k >= 0 {
- vi, fi = vi[:k], vi[k:]
- }
- if k := strings.Index(vj, "/"); k >= 0 {
- vj, fj = vj[:k], vj[k:]
- }
- if vi != vj {
- return semver.Compare(vi, vj) < 0
- }
- return fi < fj
- })
-}
-
-// Safe encodings
-//
-// Module paths appear as substrings of file system paths
-// (in the download cache) and of web server URLs in the proxy protocol.
-// In general we cannot rely on file systems to be case-sensitive,
-// nor can we rely on web servers, since they read from file systems.
-// That is, we cannot rely on the file system to keep rsc.io/QUOTE
-// and rsc.io/quote separate. Windows and macOS don't.
-// Instead, we must never require two different casings of a file path.
-// Because we want the download cache to match the proxy protocol,
-// and because we want the proxy protocol to be possible to serve
-// from a tree of static files (which might be stored on a case-insensitive
-// file system), the proxy protocol must never require two different casings
-// of a URL path either.
-//
-// One possibility would be to make the safe encoding be the lowercase
-// hexadecimal encoding of the actual path bytes. This would avoid ever
-// needing different casings of a file path, but it would be fairly illegible
-// to most programmers when those paths appeared in the file system
-// (including in file paths in compiler errors and stack traces)
-// in web server logs, and so on. Instead, we want a safe encoding that
-// leaves most paths unaltered.
-//
-// The safe encoding is this:
-// replace every uppercase letter with an exclamation mark
-// followed by the letter's lowercase equivalent.
-//
-// For example,
-// github.com/Azure/azure-sdk-for-go -> github.com/!azure/azure-sdk-for-go.
-// github.com/GoogleCloudPlatform/cloudsql-proxy -> github.com/!google!cloud!platform/cloudsql-proxy
-// github.com/Sirupsen/logrus -> github.com/!sirupsen/logrus.
-//
-// Import paths that avoid upper-case letters are left unchanged.
-// Note that because import paths are ASCII-only and avoid various
-// problematic punctuation (like : < and >), the safe encoding is also ASCII-only
-// and avoids the same problematic punctuation.
-//
-// Import paths have never allowed exclamation marks, so there is no
-// need to define how to encode a literal !.
-//
-// Although paths are disallowed from using Unicode (see pathOK above),
-// the eventual plan is to allow Unicode letters as well, to assume that
-// file systems and URLs are Unicode-safe (storing UTF-8), and apply
-// the !-for-uppercase convention. Note however that not all runes that
-// are different but case-fold equivalent are an upper/lower pair.
-// For example, U+004B ('K'), U+006B ('k'), and U+212A ('K' for Kelvin)
-// are considered to case-fold to each other. When we do add Unicode
-// letters, we must not assume that upper/lower are the only case-equivalent pairs.
-// Perhaps the Kelvin symbol would be disallowed entirely, for example.
-// Or perhaps it would encode as "!!k", or perhaps as "(212A)".
-//
-// Also, it would be nice to allow Unicode marks as well as letters,
-// but marks include combining marks, and then we must deal not
-// only with case folding but also normalization: both U+00E9 ('é')
-// and U+0065 U+0301 ('e' followed by combining acute accent)
-// look the same on the page and are treated by some file systems
-// as the same path. If we do allow Unicode marks in paths, there
-// must be some kind of normalization to allow only one canonical
-// encoding of any character used in an import path.
-
-// EncodePath returns the safe encoding of the given module path.
-// It fails if the module path is invalid.
-func EncodePath(path string) (encoding string, err error) {
- if err := CheckPath(path); err != nil {
- return "", err
- }
-
- return encodeString(path)
-}
-
-// EncodeVersion returns the safe encoding of the given module version.
-// Versions are allowed to be in non-semver form but must be valid file names
-// and not contain exclamation marks.
-func EncodeVersion(v string) (encoding string, err error) {
- if err := checkElem(v, true); err != nil || strings.Contains(v, "!") {
- return "", &InvalidVersionError{
- Version: v,
- Err: fmt.Errorf("disallowed version string"),
- }
- }
- return encodeString(v)
-}
-
-func encodeString(s string) (encoding string, err error) {
- haveUpper := false
- for _, r := range s {
- if r == '!' || r >= utf8.RuneSelf {
- // This should be disallowed by CheckPath, but diagnose anyway.
- // The correctness of the encoding loop below depends on it.
- return "", fmt.Errorf("internal error: inconsistency in EncodePath")
- }
- if 'A' <= r && r <= 'Z' {
- haveUpper = true
- }
- }
-
- if !haveUpper {
- return s, nil
- }
-
- var buf []byte
- for _, r := range s {
- if 'A' <= r && r <= 'Z' {
- buf = append(buf, '!', byte(r+'a'-'A'))
- } else {
- buf = append(buf, byte(r))
- }
- }
- return string(buf), nil
-}
-
-// DecodePath returns the module path of the given safe encoding.
-// It fails if the encoding is invalid or encodes an invalid path.
-func DecodePath(encoding string) (path string, err error) {
- path, ok := decodeString(encoding)
- if !ok {
- return "", fmt.Errorf("invalid module path encoding %q", encoding)
- }
- if err := CheckPath(path); err != nil {
- return "", fmt.Errorf("invalid module path encoding %q: %v", encoding, err)
- }
- return path, nil
-}
-
-// DecodeVersion returns the version string for the given safe encoding.
-// It fails if the encoding is invalid or encodes an invalid version.
-// Versions are allowed to be in non-semver form but must be valid file names
-// and not contain exclamation marks.
-func DecodeVersion(encoding string) (v string, err error) {
- v, ok := decodeString(encoding)
- if !ok {
- return "", fmt.Errorf("invalid version encoding %q", encoding)
- }
- if err := checkElem(v, true); err != nil {
- return "", fmt.Errorf("disallowed version string %q", v)
- }
- return v, nil
-}
-
-func decodeString(encoding string) (string, bool) {
- var buf []byte
-
- bang := false
- for _, r := range encoding {
- if r >= utf8.RuneSelf {
- return "", false
- }
- if bang {
- bang = false
- if r < 'a' || 'z' < r {
- return "", false
- }
- buf = append(buf, byte(r+'A'-'a'))
- continue
- }
- if r == '!' {
- bang = true
- continue
- }
- if 'A' <= r && r <= 'Z' {
- return "", false
- }
- buf = append(buf, byte(r))
- }
- if bang {
- return "", false
- }
- return string(buf), true
-}