From 65aa53fc52ff15efe54df4147564828d535837f8 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 11 Oct 2024 12:27:00 +0200 Subject: Adding upstream version 8.0.3. Signed-off-by: Daniel Baumann --- modules/git/repo_attribute.go | 286 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 286 insertions(+) create mode 100644 modules/git/repo_attribute.go (limited to 'modules/git/repo_attribute.go') diff --git a/modules/git/repo_attribute.go b/modules/git/repo_attribute.go new file mode 100644 index 00000000..3ccc1b84 --- /dev/null +++ b/modules/git/repo_attribute.go @@ -0,0 +1,286 @@ +// Copyright 2019 The Gitea Authors. All rights reserved. +// SPDX-License-Identifier: MIT + +package git + +import ( + "bufio" + "bytes" + "context" + "fmt" + "io" + "os" + "strings" + "sync/atomic" + + "code.gitea.io/gitea/modules/optional" +) + +var LinguistAttributes = []string{"linguist-vendored", "linguist-generated", "linguist-language", "gitlab-language", "linguist-documentation", "linguist-detectable"} + +// newCheckAttrStdoutReader parses the nul-byte separated output of git check-attr on each call of +// the returned function. The first reading error will stop the reading and be returned on all +// subsequent calls. +func newCheckAttrStdoutReader(r io.Reader, count int) func() (map[string]GitAttribute, error) { + scanner := bufio.NewScanner(r) + + // adapted from bufio.ScanLines to split on nul-byte \x00 + scanner.Split(func(data []byte, atEOF bool) (advance int, token []byte, err error) { + if atEOF && len(data) == 0 { + return 0, nil, nil + } + if i := bytes.IndexByte(data, '\x00'); i >= 0 { + // We have a full nul-terminated line. + return i + 1, data[0:i], nil + } + // If we're at EOF, we have a final, non-terminated line. Return it. + if atEOF { + return len(data), data, nil + } + // Request more data. + return 0, nil, nil + }) + + var err error + nextText := func() string { + if err != nil { + return "" + } + if !scanner.Scan() { + err = scanner.Err() + if err == nil { + err = io.ErrUnexpectedEOF + } + return "" + } + return scanner.Text() + } + nextAttribute := func() (string, GitAttribute, error) { + nextText() // discard filename + key := nextText() + value := GitAttribute(nextText()) + return key, value, err + } + return func() (map[string]GitAttribute, error) { + values := make(map[string]GitAttribute, count) + for range count { + k, v, err := nextAttribute() + if err != nil { + return values, err + } + values[k] = v + } + return values, scanner.Err() + } +} + +// GitAttribute exposes an attribute from the .gitattribute file +type GitAttribute string //nolint:revive + +// IsSpecified returns true if the gitattribute is set and not empty +func (ca GitAttribute) IsSpecified() bool { + return ca != "" && ca != "unspecified" +} + +// String returns the value of the attribute or "" if unspecified +func (ca GitAttribute) String() string { + if !ca.IsSpecified() { + return "" + } + return string(ca) +} + +// Prefix returns the value of the attribute before any question mark '?' +// +// sometimes used within gitlab-language: https://docs.gitlab.com/ee/user/project/highlighting.html#override-syntax-highlighting-for-a-file-type +func (ca GitAttribute) Prefix() string { + s := ca.String() + if i := strings.IndexByte(s, '?'); i >= 0 { + return s[:i] + } + return s +} + +// Bool returns true if "set"/"true", false if "unset"/"false", none otherwise +func (ca GitAttribute) Bool() optional.Option[bool] { + switch ca { + case "set", "true": + return optional.Some(true) + case "unset", "false": + return optional.Some(false) + } + return optional.None[bool]() +} + +// gitCheckAttrCommand prepares the "git check-attr" command for later use as one-shot or streaming +// instantiation. +func (repo *Repository) gitCheckAttrCommand(treeish string, attributes ...string) (*Command, *RunOpts, context.CancelFunc, error) { + if len(attributes) == 0 { + return nil, nil, nil, fmt.Errorf("no provided attributes to check-attr") + } + + env := os.Environ() + var removeTempFiles context.CancelFunc = func() {} + + // git < 2.40 cannot run check-attr on bare repo, but needs INDEX + WORK_TREE + hasIndex := treeish == "" + if !hasIndex && !SupportCheckAttrOnBare { + indexFilename, worktree, cancel, err := repo.ReadTreeToTemporaryIndex(treeish) + if err != nil { + return nil, nil, nil, err + } + removeTempFiles = cancel + + env = append(env, "GIT_INDEX_FILE="+indexFilename, "GIT_WORK_TREE="+worktree) + + hasIndex = true + + // clear treeish to read from provided index/work_tree + treeish = "" + } + + cmd := NewCommand(repo.Ctx, "check-attr", "-z") + + if hasIndex { + cmd.AddArguments("--cached") + } + + if len(treeish) > 0 { + cmd.AddArguments("--source") + cmd.AddDynamicArguments(treeish) + } + cmd.AddDynamicArguments(attributes...) + + // Version 2.43.1 has a bug where the behavior of `GIT_FLUSH` is flipped. + // Ref: https://lore.kernel.org/git/CABn0oJvg3M_kBW-u=j3QhKnO=6QOzk-YFTgonYw_UvFS1NTX4g@mail.gmail.com + if InvertedGitFlushEnv { + env = append(env, "GIT_FLUSH=0") + } else { + env = append(env, "GIT_FLUSH=1") + } + + return cmd, &RunOpts{ + Env: env, + Dir: repo.Path, + }, removeTempFiles, nil +} + +// GitAttributeFirst returns the first specified attribute of the given filename. +// +// If treeish is empty, the gitattribute will be read from the current repo (which MUST be a working directory and NOT bare). +func (repo *Repository) GitAttributeFirst(treeish, filename string, attributes ...string) (GitAttribute, error) { + values, err := repo.GitAttributes(treeish, filename, attributes...) + if err != nil { + return "", err + } + for _, a := range attributes { + if values[a].IsSpecified() { + return values[a], nil + } + } + return "", nil +} + +// GitAttributes returns the gitattribute of the given filename. +// +// If treeish is empty, the gitattribute will be read from the current repo (which MUST be a working directory and NOT bare). +func (repo *Repository) GitAttributes(treeish, filename string, attributes ...string) (map[string]GitAttribute, error) { + cmd, runOpts, removeTempFiles, err := repo.gitCheckAttrCommand(treeish, attributes...) + if err != nil { + return nil, err + } + defer removeTempFiles() + + stdOut := new(bytes.Buffer) + runOpts.Stdout = stdOut + + stdErr := new(bytes.Buffer) + runOpts.Stderr = stdErr + + cmd.AddDashesAndList(filename) + + if err := cmd.Run(runOpts); err != nil { + return nil, fmt.Errorf("failed to run check-attr: %w\n%s\n%s", err, stdOut.String(), stdErr.String()) + } + + return newCheckAttrStdoutReader(stdOut, len(attributes))() +} + +// GitAttributeChecker creates an AttributeChecker for the given repository and provided commit ID +// to retrieve the attributes of multiple files. The AttributeChecker must be closed after use. +// +// If treeish is empty, the gitattribute will be read from the current repo (which MUST be a working directory and NOT bare). +func (repo *Repository) GitAttributeChecker(treeish string, attributes ...string) (AttributeChecker, error) { + cmd, runOpts, removeTempFiles, err := repo.gitCheckAttrCommand(treeish, attributes...) + if err != nil { + return AttributeChecker{}, err + } + + cmd.AddArguments("--stdin") + + // os.Pipe is needed (and not io.Pipe), otherwise cmd.Wait will wait for the stdinReader + // to be closed before returning (which would require another goroutine) + // https://go.dev/issue/23019 + stdinReader, stdinWriter, err := os.Pipe() // reader closed in goroutine / writer closed on ac.Close + if err != nil { + return AttributeChecker{}, err + } + stdoutReader, stdoutWriter := io.Pipe() // closed in goroutine + + ac := AttributeChecker{ + removeTempFiles: removeTempFiles, // called on ac.Close + stdinWriter: stdinWriter, + readStdout: newCheckAttrStdoutReader(stdoutReader, len(attributes)), + err: &atomic.Value{}, + } + + go func() { + defer stdinReader.Close() + defer stdoutWriter.Close() // in case of a panic (no-op if already closed by CloseWithError at the end) + + stdErr := new(bytes.Buffer) + runOpts.Stdin = stdinReader + runOpts.Stdout = stdoutWriter + runOpts.Stderr = stdErr + + err := cmd.Run(runOpts) + + // if the context was cancelled, Run error is irrelevant + if e := cmd.parentContext.Err(); e != nil { + err = e + } + + if err != nil { // decorate the returned error + err = fmt.Errorf("git check-attr (stderr: %q): %w", strings.TrimSpace(stdErr.String()), err) + ac.err.Store(err) + } + stdoutWriter.CloseWithError(err) + }() + + return ac, nil +} + +type AttributeChecker struct { + removeTempFiles context.CancelFunc + stdinWriter io.WriteCloser + readStdout func() (map[string]GitAttribute, error) + err *atomic.Value +} + +func (ac AttributeChecker) CheckPath(path string) (map[string]GitAttribute, error) { + if _, err := ac.stdinWriter.Write([]byte(path + "\x00")); err != nil { + // try to return the Run error if available, since it is likely more helpful + // than just "broken pipe" + if aerr, _ := ac.err.Load().(error); aerr != nil { + return nil, aerr + } + return nil, fmt.Errorf("git check-attr: %w", err) + } + + return ac.readStdout() +} + +func (ac AttributeChecker) Close() error { + ac.removeTempFiles() + return ac.stdinWriter.Close() +} -- cgit v1.2.3