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authorDaniel Baumann <daniel@debian.org>2024-10-18 20:33:49 +0200
committerDaniel Baumann <daniel@debian.org>2024-10-18 20:33:49 +0200
commitdd136858f1ea40ad3c94191d647487fa4f31926c (patch)
tree58fec94a7b2a12510c9664b21793f1ed560c6518 /modules/git/repo_attribute.go
parentInitial commit. (diff)
downloadforgejo-dd136858f1ea40ad3c94191d647487fa4f31926c.tar.xz
forgejo-dd136858f1ea40ad3c94191d647487fa4f31926c.zip
Adding upstream version 9.0.0.upstream/9.0.0upstreamdebian
Signed-off-by: Daniel Baumann <daniel@debian.org>
Diffstat (limited to 'modules/git/repo_attribute.go')
-rw-r--r--modules/git/repo_attribute.go286
1 files changed, 286 insertions, 0 deletions
diff --git a/modules/git/repo_attribute.go b/modules/git/repo_attribute.go
new file mode 100644
index 0000000..3ccc1b8
--- /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()
+}