forgejo-federation/modules/git/parse_nogogit.go
wxiaoguang c08e42c47e
Refactor parseTreeEntries, speed up tree list (#21368)
Close #20315 (fix the panic when parsing invalid input), Speed up #20231 (use ls-tree without size field)

Introduce ListEntriesRecursiveFast (ls-tree without size) and ListEntriesRecursiveWithSize (ls-tree with size)
2022-10-08 01:20:53 +08:00

140 lines
3.7 KiB
Go

// Copyright 2018 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
//go:build !gogit
package git
import (
"bufio"
"bytes"
"fmt"
"io"
"strconv"
"strings"
"code.gitea.io/gitea/modules/log"
)
// ParseTreeEntries parses the output of a `git ls-tree -l` command.
func ParseTreeEntries(data []byte) ([]*TreeEntry, error) {
return parseTreeEntries(data, nil)
}
var sepSpace = []byte{' '}
func parseTreeEntries(data []byte, ptree *Tree) ([]*TreeEntry, error) {
var err error
entries := make([]*TreeEntry, 0, bytes.Count(data, []byte{'\n'})+1)
for pos := 0; pos < len(data); {
// expect line to be of the form:
// <mode> <type> <sha> <space-padded-size>\t<filename>
// <mode> <type> <sha>\t<filename>
posEnd := bytes.IndexByte(data[pos:], '\n')
if posEnd == -1 {
posEnd = len(data)
} else {
posEnd += pos
}
line := data[pos:posEnd]
posTab := bytes.IndexByte(line, '\t')
if posTab == -1 {
return nil, fmt.Errorf("invalid ls-tree output (no tab): %q", line)
}
entry := new(TreeEntry)
entry.ptree = ptree
entryAttrs := line[:posTab]
entryName := line[posTab+1:]
entryMode, entryAttrs, _ := bytes.Cut(entryAttrs, sepSpace)
_ /* entryType */, entryAttrs, _ = bytes.Cut(entryAttrs, sepSpace) // the type is not used, the mode is enough to determine the type
entryObjectID, entryAttrs, _ := bytes.Cut(entryAttrs, sepSpace)
if len(entryAttrs) > 0 {
entrySize := entryAttrs // the last field is the space-padded-size
entry.size, _ = strconv.ParseInt(strings.TrimSpace(string(entrySize)), 10, 64)
entry.sized = true
}
switch string(entryMode) {
case "100644":
entry.entryMode = EntryModeBlob
case "100755":
entry.entryMode = EntryModeExec
case "120000":
entry.entryMode = EntryModeSymlink
case "160000":
entry.entryMode = EntryModeCommit
case "040000", "040755": // git uses 040000 for tree object, but some users may get 040755 for unknown reasons
entry.entryMode = EntryModeTree
default:
return nil, fmt.Errorf("unknown type: %v", string(entryMode))
}
entry.ID, err = NewIDFromString(string(entryObjectID))
if err != nil {
return nil, fmt.Errorf("invalid ls-tree output (invalid object id): %q, err: %w", line, err)
}
if len(entryName) > 0 && entryName[0] == '"' {
entry.name, err = strconv.Unquote(string(entryName))
if err != nil {
return nil, fmt.Errorf("invalid ls-tree output (invalid name): %q, err: %w", line, err)
}
} else {
entry.name = string(entryName)
}
pos = posEnd + 1
entries = append(entries, entry)
}
return entries, nil
}
func catBatchParseTreeEntries(ptree *Tree, rd *bufio.Reader, sz int64) ([]*TreeEntry, error) {
fnameBuf := make([]byte, 4096)
modeBuf := make([]byte, 40)
shaBuf := make([]byte, 40)
entries := make([]*TreeEntry, 0, 10)
loop:
for sz > 0 {
mode, fname, sha, count, err := ParseTreeLine(rd, modeBuf, fnameBuf, shaBuf)
if err != nil {
if err == io.EOF {
break loop
}
return nil, err
}
sz -= int64(count)
entry := new(TreeEntry)
entry.ptree = ptree
switch string(mode) {
case "100644":
entry.entryMode = EntryModeBlob
case "100755":
entry.entryMode = EntryModeExec
case "120000":
entry.entryMode = EntryModeSymlink
case "160000":
entry.entryMode = EntryModeCommit
case "40000", "40755": // git uses 40000 for tree object, but some users may get 40755 for unknown reasons
entry.entryMode = EntryModeTree
default:
log.Debug("Unknown mode: %v", string(mode))
return nil, fmt.Errorf("unknown mode: %v", string(mode))
}
entry.ID = MustID(sha)
entry.name = string(fname)
entries = append(entries, entry)
}
if _, err := rd.Discard(1); err != nil {
return entries, err
}
return entries, nil
}