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-rw-r--r--src/cmd/go/vcs.go674
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diff --git a/src/cmd/go/vcs.go b/src/cmd/go/vcs.go
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+// Copyright 2012 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 main
+
+import (
+ "bytes"
+ "encoding/json"
+ "errors"
+ "fmt"
+ "log"
+ "os"
+ "os/exec"
+ "path/filepath"
+ "regexp"
+ "strings"
+)
+
+// A vcsCmd describes how to use a version control system
+// like Mercurial, Git, or Subversion.
+type vcsCmd struct {
+ name string
+ cmd string // name of binary to invoke command
+
+ createCmd string // command to download a fresh copy of a repository
+ downloadCmd string // command to download updates into an existing repository
+
+ tagCmd []tagCmd // commands to list tags
+ tagLookupCmd []tagCmd // commands to lookup tags before running tagSyncCmd
+ tagSyncCmd string // command to sync to specific tag
+ tagSyncDefault string // command to sync to default tag
+
+ scheme []string
+ pingCmd string
+}
+
+// A tagCmd describes a command to list available tags
+// that can be passed to tagSyncCmd.
+type tagCmd struct {
+ cmd string // command to list tags
+ pattern string // regexp to extract tags from list
+}
+
+// vcsList lists the known version control systems
+var vcsList = []*vcsCmd{
+ vcsHg,
+ vcsGit,
+ vcsSvn,
+ vcsBzr,
+}
+
+// vcsByCmd returns the version control system for the given
+// command name (hg, git, svn, bzr).
+func vcsByCmd(cmd string) *vcsCmd {
+ for _, vcs := range vcsList {
+ if vcs.cmd == cmd {
+ return vcs
+ }
+ }
+ return nil
+}
+
+// vcsHg describes how to use Mercurial.
+var vcsHg = &vcsCmd{
+ name: "Mercurial",
+ cmd: "hg",
+
+ createCmd: "clone -U {repo} {dir}",
+ downloadCmd: "pull",
+
+ // We allow both tag and branch names as 'tags'
+ // for selecting a version. This lets people have
+ // a go.release.r60 branch and a go1 branch
+ // and make changes in both, without constantly
+ // editing .hgtags.
+ tagCmd: []tagCmd{
+ {"tags", `^(\S+)`},
+ {"branches", `^(\S+)`},
+ },
+ tagSyncCmd: "update -r {tag}",
+ tagSyncDefault: "update default",
+
+ scheme: []string{"https", "http"},
+ pingCmd: "identify {scheme}://{repo}",
+}
+
+// vcsGit describes how to use Git.
+var vcsGit = &vcsCmd{
+ name: "Git",
+ cmd: "git",
+
+ createCmd: "clone {repo} {dir}",
+ downloadCmd: "fetch",
+
+ tagCmd: []tagCmd{
+ // tags/xxx matches a git tag named xxx
+ // origin/xxx matches a git branch named xxx on the default remote repository
+ {"show-ref", `(?:tags|origin)/(\S+)$`},
+ },
+ tagLookupCmd: []tagCmd{
+ {"show-ref tags/{tag} origin/{tag}", `((?:tags|origin)/\S+)$`},
+ },
+ tagSyncCmd: "checkout {tag}",
+ tagSyncDefault: "checkout origin/master",
+
+ scheme: []string{"git", "https", "http", "git+ssh"},
+ pingCmd: "ls-remote {scheme}://{repo}",
+}
+
+// vcsBzr describes how to use Bazaar.
+var vcsBzr = &vcsCmd{
+ name: "Bazaar",
+ cmd: "bzr",
+
+ createCmd: "branch {repo} {dir}",
+
+ // Without --overwrite bzr will not pull tags that changed.
+ // Replace by --overwrite-tags after http://pad.lv/681792 goes in.
+ downloadCmd: "pull --overwrite",
+
+ tagCmd: []tagCmd{{"tags", `^(\S+)`}},
+ tagSyncCmd: "update -r {tag}",
+ tagSyncDefault: "update -r revno:-1",
+
+ scheme: []string{"https", "http", "bzr", "bzr+ssh"},
+ pingCmd: "info {scheme}://{repo}",
+}
+
+// vcsSvn describes how to use Subversion.
+var vcsSvn = &vcsCmd{
+ name: "Subversion",
+ cmd: "svn",
+
+ createCmd: "checkout {repo} {dir}",
+ downloadCmd: "update",
+
+ // There is no tag command in subversion.
+ // The branch information is all in the path names.
+
+ scheme: []string{"https", "http", "svn", "svn+ssh"},
+ pingCmd: "info {scheme}://{repo}",
+}
+
+func (v *vcsCmd) String() string {
+ return v.name
+}
+
+// run runs the command line cmd in the given directory.
+// keyval is a list of key, value pairs. run expands
+// instances of {key} in cmd into value, but only after
+// splitting cmd into individual arguments.
+// If an error occurs, run prints the command line and the
+// command's combined stdout+stderr to standard error.
+// Otherwise run discards the command's output.
+func (v *vcsCmd) run(dir string, cmd string, keyval ...string) error {
+ _, err := v.run1(dir, cmd, keyval, true)
+ return err
+}
+
+// runVerboseOnly is like run but only generates error output to standard error in verbose mode.
+func (v *vcsCmd) runVerboseOnly(dir string, cmd string, keyval ...string) error {
+ _, err := v.run1(dir, cmd, keyval, false)
+ return err
+}
+
+// runOutput is like run but returns the output of the command.
+func (v *vcsCmd) runOutput(dir string, cmd string, keyval ...string) ([]byte, error) {
+ return v.run1(dir, cmd, keyval, true)
+}
+
+// run1 is the generalized implementation of run and runOutput.
+func (v *vcsCmd) run1(dir string, cmdline string, keyval []string, verbose bool) ([]byte, error) {
+ m := make(map[string]string)
+ for i := 0; i < len(keyval); i += 2 {
+ m[keyval[i]] = keyval[i+1]
+ }
+ args := strings.Fields(cmdline)
+ for i, arg := range args {
+ args[i] = expand(m, arg)
+ }
+
+ cmd := exec.Command(v.cmd, args...)
+ cmd.Dir = dir
+ if buildX {
+ fmt.Printf("cd %s\n", dir)
+ fmt.Printf("%s %s\n", v.cmd, strings.Join(args, " "))
+ }
+ var buf bytes.Buffer
+ cmd.Stdout = &buf
+ cmd.Stderr = &buf
+ err := cmd.Run()
+ out := buf.Bytes()
+ if err != nil {
+ if verbose || buildV {
+ fmt.Fprintf(os.Stderr, "# cd %s; %s %s\n", dir, v.cmd, strings.Join(args, " "))
+ os.Stderr.Write(out)
+ }
+ return nil, err
+ }
+ return out, nil
+}
+
+// ping pings to determine scheme to use.
+func (v *vcsCmd) ping(scheme, repo string) error {
+ return v.runVerboseOnly(".", v.pingCmd, "scheme", scheme, "repo", repo)
+}
+
+// create creates a new copy of repo in dir.
+// The parent of dir must exist; dir must not.
+func (v *vcsCmd) create(dir, repo string) error {
+ return v.run(".", v.createCmd, "dir", dir, "repo", repo)
+}
+
+// download downloads any new changes for the repo in dir.
+func (v *vcsCmd) download(dir string) error {
+ return v.run(dir, v.downloadCmd)
+}
+
+// tags returns the list of available tags for the repo in dir.
+func (v *vcsCmd) tags(dir string) ([]string, error) {
+ var tags []string
+ for _, tc := range v.tagCmd {
+ out, err := v.runOutput(dir, tc.cmd)
+ if err != nil {
+ return nil, err
+ }
+ re := regexp.MustCompile(`(?m-s)` + tc.pattern)
+ for _, m := range re.FindAllStringSubmatch(string(out), -1) {
+ tags = append(tags, m[1])
+ }
+ }
+ return tags, nil
+}
+
+// tagSync syncs the repo in dir to the named tag,
+// which either is a tag returned by tags or is v.tagDefault.
+func (v *vcsCmd) tagSync(dir, tag string) error {
+ if v.tagSyncCmd == "" {
+ return nil
+ }
+ if tag != "" {
+ for _, tc := range v.tagLookupCmd {
+ out, err := v.runOutput(dir, tc.cmd, "tag", tag)
+ if err != nil {
+ return err
+ }
+ re := regexp.MustCompile(`(?m-s)` + tc.pattern)
+ m := re.FindStringSubmatch(string(out))
+ if len(m) > 1 {
+ tag = m[1]
+ break
+ }
+ }
+ }
+ if tag == "" && v.tagSyncDefault != "" {
+ return v.run(dir, v.tagSyncDefault)
+ }
+ return v.run(dir, v.tagSyncCmd, "tag", tag)
+}
+
+// A vcsPath describes how to convert an import path into a
+// version control system and repository name.
+type vcsPath struct {
+ prefix string // prefix this description applies to
+ re string // pattern for import path
+ repo string // repository to use (expand with match of re)
+ vcs string // version control system to use (expand with match of re)
+ check func(match map[string]string) error // additional checks
+ ping bool // ping for scheme to use to download repo
+
+ regexp *regexp.Regexp // cached compiled form of re
+}
+
+// vcsForDir inspects dir and its parents to determine the
+// version control system and code repository to use.
+// On return, root is the import path
+// corresponding to the root of the repository
+// (thus root is a prefix of importPath).
+func vcsForDir(p *Package) (vcs *vcsCmd, root string, err error) {
+ // Clean and double-check that dir is in (a subdirectory of) srcRoot.
+ dir := filepath.Clean(p.Dir)
+ srcRoot := filepath.Clean(p.build.SrcRoot)
+ if len(dir) <= len(srcRoot) || dir[len(srcRoot)] != filepath.Separator {
+ return nil, "", fmt.Errorf("directory %q is outside source root %q", dir, srcRoot)
+ }
+
+ for len(dir) > len(srcRoot) {
+ for _, vcs := range vcsList {
+ if fi, err := os.Stat(filepath.Join(dir, "."+vcs.cmd)); err == nil && fi.IsDir() {
+ return vcs, dir[len(srcRoot)+1:], nil
+ }
+ }
+
+ // Move to parent.
+ ndir := filepath.Dir(dir)
+ if len(ndir) >= len(dir) {
+ // Shouldn't happen, but just in case, stop.
+ break
+ }
+ dir = ndir
+ }
+
+ return nil, "", fmt.Errorf("directory %q is not using a known version control system", dir)
+}
+
+// repoRoot represents a version control system, a repo, and a root of
+// where to put it on disk.
+type repoRoot struct {
+ vcs *vcsCmd
+
+ // repo is the repository URL, including scheme
+ repo string
+
+ // root is the import path corresponding to the root of the
+ // repository
+ root string
+}
+
+// repoRootForImportPath analyzes importPath to determine the
+// version control system, and code repository to use.
+func repoRootForImportPath(importPath string) (*repoRoot, error) {
+ rr, err := repoRootForImportPathStatic(importPath, "")
+ if err == errUnknownSite {
+ rr, err = repoRootForImportDynamic(importPath)
+
+ // repoRootForImportDynamic returns error detail
+ // that is irrelevant if the user didn't intend to use a
+ // dynamic import in the first place.
+ // Squelch it.
+ if err != nil {
+ if buildV {
+ log.Printf("import %q: %v", importPath, err)
+ }
+ err = fmt.Errorf("unrecognized import path %q", importPath)
+ }
+ }
+
+ if err == nil && strings.Contains(importPath, "...") && strings.Contains(rr.root, "...") {
+ // Do not allow wildcards in the repo root.
+ rr = nil
+ err = fmt.Errorf("cannot expand ... in %q", importPath)
+ }
+ return rr, err
+}
+
+var errUnknownSite = errors.New("dynamic lookup required to find mapping")
+
+// repoRootForImportPathStatic attempts to map importPath to a
+// repoRoot using the commonly-used VCS hosting sites in vcsPaths
+// (github.com/user/dir), or from a fully-qualified importPath already
+// containing its VCS type (foo.com/repo.git/dir)
+//
+// If scheme is non-empty, that scheme is forced.
+func repoRootForImportPathStatic(importPath, scheme string) (*repoRoot, error) {
+ if strings.Contains(importPath, "://") {
+ return nil, fmt.Errorf("invalid import path %q", importPath)
+ }
+ for _, srv := range vcsPaths {
+ if !strings.HasPrefix(importPath, srv.prefix) {
+ continue
+ }
+ m := srv.regexp.FindStringSubmatch(importPath)
+ if m == nil {
+ if srv.prefix != "" {
+ return nil, fmt.Errorf("invalid %s import path %q", srv.prefix, importPath)
+ }
+ continue
+ }
+
+ // Build map of named subexpression matches for expand.
+ match := map[string]string{
+ "prefix": srv.prefix,
+ "import": importPath,
+ }
+ for i, name := range srv.regexp.SubexpNames() {
+ if name != "" && match[name] == "" {
+ match[name] = m[i]
+ }
+ }
+ if srv.vcs != "" {
+ match["vcs"] = expand(match, srv.vcs)
+ }
+ if srv.repo != "" {
+ match["repo"] = expand(match, srv.repo)
+ }
+ if srv.check != nil {
+ if err := srv.check(match); err != nil {
+ return nil, err
+ }
+ }
+ vcs := vcsByCmd(match["vcs"])
+ if vcs == nil {
+ return nil, fmt.Errorf("unknown version control system %q", match["vcs"])
+ }
+ if srv.ping {
+ if scheme != "" {
+ match["repo"] = scheme + "://" + match["repo"]
+ } else {
+ for _, scheme := range vcs.scheme {
+ if vcs.ping(scheme, match["repo"]) == nil {
+ match["repo"] = scheme + "://" + match["repo"]
+ break
+ }
+ }
+ }
+ }
+ rr := &repoRoot{
+ vcs: vcs,
+ repo: match["repo"],
+ root: match["root"],
+ }
+ return rr, nil
+ }
+ return nil, errUnknownSite
+}
+
+// repoRootForImportDynamic finds a *repoRoot for a custom domain that's not
+// statically known by repoRootForImportPathStatic.
+//
+// This handles "vanity import paths" like "name.tld/pkg/foo".
+func repoRootForImportDynamic(importPath string) (*repoRoot, error) {
+ slash := strings.Index(importPath, "/")
+ if slash < 0 {
+ return nil, fmt.Errorf("missing / in import %q", importPath)
+ }
+ urlStr, body, err := httpsOrHTTP(importPath)
+ if err != nil {
+ return nil, fmt.Errorf("http/https fetch for import %q: %v", importPath, err)
+ }
+ defer body.Close()
+ metaImport, err := matchGoImport(parseMetaGoImports(body), importPath)
+ if err != nil {
+ if err != errNoMatch {
+ return nil, fmt.Errorf("parse %s: %v", urlStr, err)
+ }
+ return nil, fmt.Errorf("parse %s: no go-import meta tags", urlStr)
+ }
+ if buildV {
+ log.Printf("get %q: found meta tag %#v at %s", importPath, metaImport, urlStr)
+ }
+ // If the import was "uni.edu/bob/project", which said the
+ // prefix was "uni.edu" and the RepoRoot was "evilroot.com",
+ // make sure we don't trust Bob and check out evilroot.com to
+ // "uni.edu" yet (possibly overwriting/preempting another
+ // non-evil student). Instead, first verify the root and see
+ // if it matches Bob's claim.
+ if metaImport.Prefix != importPath {
+ if buildV {
+ log.Printf("get %q: verifying non-authoritative meta tag", importPath)
+ }
+ urlStr0 := urlStr
+ urlStr, body, err = httpsOrHTTP(metaImport.Prefix)
+ if err != nil {
+ return nil, fmt.Errorf("fetch %s: %v", urlStr, err)
+ }
+ imports := parseMetaGoImports(body)
+ if len(imports) == 0 {
+ return nil, fmt.Errorf("fetch %s: no go-import meta tag", urlStr)
+ }
+ metaImport2, err := matchGoImport(imports, importPath)
+ if err != nil || metaImport != metaImport2 {
+ return nil, fmt.Errorf("%s and %s disagree about go-import for %s", urlStr0, urlStr, metaImport.Prefix)
+ }
+ }
+
+ if !strings.Contains(metaImport.RepoRoot, "://") {
+ return nil, fmt.Errorf("%s: invalid repo root %q; no scheme", urlStr, metaImport.RepoRoot)
+ }
+ rr := &repoRoot{
+ vcs: vcsByCmd(metaImport.VCS),
+ repo: metaImport.RepoRoot,
+ root: metaImport.Prefix,
+ }
+ if rr.vcs == nil {
+ return nil, fmt.Errorf("%s: unknown vcs %q", urlStr, metaImport.VCS)
+ }
+ return rr, nil
+}
+
+// metaImport represents the parsed <meta name="go-import"
+// content="prefix vcs reporoot" /> tags from HTML files.
+type metaImport struct {
+ Prefix, VCS, RepoRoot string
+}
+
+// errNoMatch is returned from matchGoImport when there's no applicable match.
+var errNoMatch = errors.New("no import match")
+
+// matchGoImport returns the metaImport from imports matching importPath.
+// An error is returned if there are multiple matches.
+// errNoMatch is returned if none match.
+func matchGoImport(imports []metaImport, importPath string) (_ metaImport, err error) {
+ match := -1
+ for i, im := range imports {
+ if !strings.HasPrefix(importPath, im.Prefix) {
+ continue
+ }
+ if match != -1 {
+ err = fmt.Errorf("multiple meta tags match import path %q", importPath)
+ return
+ }
+ match = i
+ }
+ if match == -1 {
+ err = errNoMatch
+ return
+ }
+ return imports[match], nil
+}
+
+// expand rewrites s to replace {k} with match[k] for each key k in match.
+func expand(match map[string]string, s string) string {
+ for k, v := range match {
+ s = strings.Replace(s, "{"+k+"}", v, -1)
+ }
+ return s
+}
+
+// vcsPaths lists the known vcs paths.
+var vcsPaths = []*vcsPath{
+ // Google Code - new syntax
+ {
+ prefix: "code.google.com/",
+ re: `^(?P<root>code\.google\.com/p/(?P<project>[a-z0-9\-]+)(\.(?P<subrepo>[a-z0-9\-]+))?)(/[A-Za-z0-9_.\-]+)*$`,
+ repo: "https://{root}",
+ check: googleCodeVCS,
+ },
+
+ // Google Code - old syntax
+ {
+ re: `^(?P<project>[a-z0-9_\-.]+)\.googlecode\.com/(git|hg|svn)(?P<path>/.*)?$`,
+ check: oldGoogleCode,
+ },
+
+ // Github
+ {
+ prefix: "github.com/",
+ re: `^(?P<root>github\.com/[A-Za-z0-9_.\-]+/[A-Za-z0-9_.\-]+)(/[A-Za-z0-9_.\-]+)*$`,
+ vcs: "git",
+ repo: "https://{root}",
+ check: noVCSSuffix,
+ },
+
+ // Bitbucket
+ {
+ prefix: "bitbucket.org/",
+ re: `^(?P<root>bitbucket\.org/(?P<bitname>[A-Za-z0-9_.\-]+/[A-Za-z0-9_.\-]+))(/[A-Za-z0-9_.\-]+)*$`,
+ repo: "https://{root}",
+ check: bitbucketVCS,
+ },
+
+ // Launchpad
+ {
+ prefix: "launchpad.net/",
+ re: `^(?P<root>launchpad\.net/((?P<project>[A-Za-z0-9_.\-]+)(?P<series>/[A-Za-z0-9_.\-]+)?|~[A-Za-z0-9_.\-]+/(\+junk|[A-Za-z0-9_.\-]+)/[A-Za-z0-9_.\-]+))(/[A-Za-z0-9_.\-]+)*$`,
+ vcs: "bzr",
+ repo: "https://{root}",
+ check: launchpadVCS,
+ },
+
+ // General syntax for any server.
+ {
+ re: `^(?P<root>(?P<repo>([a-z0-9.\-]+\.)+[a-z0-9.\-]+(:[0-9]+)?/[A-Za-z0-9_.\-/]*?)\.(?P<vcs>bzr|git|hg|svn))(/[A-Za-z0-9_.\-]+)*$`,
+ ping: true,
+ },
+}
+
+func init() {
+ // fill in cached regexps.
+ // Doing this eagerly discovers invalid regexp syntax
+ // without having to run a command that needs that regexp.
+ for _, srv := range vcsPaths {
+ srv.regexp = regexp.MustCompile(srv.re)
+ }
+}
+
+// noVCSSuffix checks that the repository name does not
+// end in .foo for any version control system foo.
+// The usual culprit is ".git".
+func noVCSSuffix(match map[string]string) error {
+ repo := match["repo"]
+ for _, vcs := range vcsList {
+ if strings.HasSuffix(repo, "."+vcs.cmd) {
+ return fmt.Errorf("invalid version control suffix in %s path", match["prefix"])
+ }
+ }
+ return nil
+}
+
+var googleCheckout = regexp.MustCompile(`id="checkoutcmd">(hg|git|svn)`)
+
+// googleCodeVCS determines the version control system for
+// a code.google.com repository, by scraping the project's
+// /source/checkout page.
+func googleCodeVCS(match map[string]string) error {
+ if err := noVCSSuffix(match); err != nil {
+ return err
+ }
+ data, err := httpGET(expand(match, "https://code.google.com/p/{project}/source/checkout?repo={subrepo}"))
+ if err != nil {
+ return err
+ }
+
+ if m := googleCheckout.FindSubmatch(data); m != nil {
+ if vcs := vcsByCmd(string(m[1])); vcs != nil {
+ // Subversion requires the old URLs.
+ // TODO: Test.
+ if vcs == vcsSvn {
+ if match["subrepo"] != "" {
+ return fmt.Errorf("sub-repositories not supported in Google Code Subversion projects")
+ }
+ match["repo"] = expand(match, "https://{project}.googlecode.com/svn")
+ }
+ match["vcs"] = vcs.cmd
+ return nil
+ }
+ }
+
+ return fmt.Errorf("unable to detect version control system for code.google.com/ path")
+}
+
+// oldGoogleCode is invoked for old-style foo.googlecode.com paths.
+// It prints an error giving the equivalent new path.
+func oldGoogleCode(match map[string]string) error {
+ return fmt.Errorf("invalid Google Code import path: use %s instead",
+ expand(match, "code.google.com/p/{project}{path}"))
+}
+
+// bitbucketVCS determines the version control system for a
+// BitBucket repository, by using the BitBucket API.
+func bitbucketVCS(match map[string]string) error {
+ if err := noVCSSuffix(match); err != nil {
+ return err
+ }
+
+ var resp struct {
+ SCM string `json:"scm"`
+ }
+ url := expand(match, "https://api.bitbucket.org/1.0/repositories/{bitname}")
+ data, err := httpGET(url)
+ if err != nil {
+ return err
+ }
+ if err := json.Unmarshal(data, &resp); err != nil {
+ return fmt.Errorf("decoding %s: %v", url, err)
+ }
+
+ if vcsByCmd(resp.SCM) != nil {
+ match["vcs"] = resp.SCM
+ if resp.SCM == "git" {
+ match["repo"] += ".git"
+ }
+ return nil
+ }
+
+ return fmt.Errorf("unable to detect version control system for bitbucket.org/ path")
+}
+
+// launchpadVCS solves the ambiguity for "lp.net/project/foo". In this case,
+// "foo" could be a series name registered in Launchpad with its own branch,
+// and it could also be the name of a directory within the main project
+// branch one level up.
+func launchpadVCS(match map[string]string) error {
+ if match["project"] == "" || match["series"] == "" {
+ return nil
+ }
+ _, err := httpGET(expand(match, "https://code.launchpad.net/{project}{series}/.bzr/branch-format"))
+ if err != nil {
+ match["root"] = expand(match, "launchpad.net/{project}")
+ match["repo"] = expand(match, "https://{root}")
+ }
+ return nil
+}