1 files changed, 370 insertions, 0 deletions
diff --git a/modules/git/commit_info_nogogit.go b/modules/git/commit_info_nogogit.go
new file mode 100644
index 0000000000..ac0c7cff5d
--- /dev/null
+++ b/modules/git/commit_info_nogogit.go
@@ -0,0 +1,370 @@
+// Copyright 2017 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.
+
+// +build !gogit
+
+package git
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"path"
+	"sort"
+	"strings"
+)
+
+// GetCommitsInfo gets information of all commits that are corresponding to these entries
+func (tes Entries) GetCommitsInfo(commit *Commit, treePath string, cache *LastCommitCache) ([]CommitInfo, *Commit, error) {
+	entryPaths := make([]string, len(tes)+1)
+	// Get the commit for the treePath itself
+	entryPaths[0] = ""
+	for i, entry := range tes {
+		entryPaths[i+1] = entry.Name()
+	}
+
+	var err error
+
+	var revs map[string]*Commit
+	if cache != nil {
+		var unHitPaths []string
+		revs, unHitPaths, err = getLastCommitForPathsByCache(commit.ID.String(), treePath, entryPaths, cache)
+		if err != nil {
+			return nil, nil, err
+		}
+		if len(unHitPaths) > 0 {
+			sort.Strings(unHitPaths)
+			commits, err := GetLastCommitForPaths(commit, treePath, unHitPaths)
+			if err != nil {
+				return nil, nil, err
+			}
+
+			for i, found := range commits {
+				if err := cache.Put(commit.ID.String(), path.Join(treePath, unHitPaths[i]), found.ID.String()); err != nil {
+					return nil, nil, err
+				}
+				revs[unHitPaths[i]] = found
+			}
+		}
+	} else {
+		sort.Strings(entryPaths)
+		revs = map[string]*Commit{}
+		var foundCommits []*Commit
+		foundCommits, err = GetLastCommitForPaths(commit, treePath, entryPaths)
+		for i, found := range foundCommits {
+			revs[entryPaths[i]] = found
+		}
+	}
+	if err != nil {
+		return nil, nil, err
+	}
+
+	commitsInfo := make([]CommitInfo, len(tes))
+	for i, entry := range tes {
+		commitsInfo[i] = CommitInfo{
+			Entry: entry,
+		}
+		if entryCommit, ok := revs[entry.Name()]; ok {
+			commitsInfo[i].Commit = entryCommit
+			if entry.IsSubModule() {
+				subModuleURL := ""
+				var fullPath string
+				if len(treePath) > 0 {
+					fullPath = treePath + "/" + entry.Name()
+				} else {
+					fullPath = entry.Name()
+				}
+				if subModule, err := commit.GetSubModule(fullPath); err != nil {
+					return nil, nil, err
+				} else if subModule != nil {
+					subModuleURL = subModule.URL
+				}
+				subModuleFile := NewSubModuleFile(entryCommit, subModuleURL, entry.ID.String())
+				commitsInfo[i].SubModuleFile = subModuleFile
+			}
+		}
+	}
+
+	// Retrieve the commit for the treePath itself (see above). We basically
+	// get it for free during the tree traversal and it's used for listing
+	// pages to display information about newest commit for a given path.
+	var treeCommit *Commit
+	var ok bool
+	if treePath == "" {
+		treeCommit = commit
+	} else if treeCommit, ok = revs[""]; ok {
+		treeCommit.repo = commit.repo
+	}
+	return commitsInfo, treeCommit, nil
+}
+
+func getLastCommitForPathsByCache(commitID, treePath string, paths []string, cache *LastCommitCache) (map[string]*Commit, []string, error) {
+	var unHitEntryPaths []string
+	var results = make(map[string]*Commit)
+	for _, p := range paths {
+		lastCommit, err := cache.Get(commitID, path.Join(treePath, p))
+		if err != nil {
+			return nil, nil, err
+		}
+		if lastCommit != nil {
+			results[p] = lastCommit.(*Commit)
+			continue
+		}
+
+		unHitEntryPaths = append(unHitEntryPaths, p)
+	}
+
+	return results, unHitEntryPaths, nil
+}
+
+// GetLastCommitForPaths returns last commit information
+func GetLastCommitForPaths(commit *Commit, treePath string, paths []string) ([]*Commit, error) {
+	// We read backwards from the commit to obtain all of the commits
+
+	// We'll do this by using rev-list to provide us with parent commits in order
+	revListReader, revListWriter := io.Pipe()
+	defer func() {
+		_ = revListWriter.Close()
+		_ = revListReader.Close()
+	}()
+
+	go func() {
+		stderr := strings.Builder{}
+		err := NewCommand("rev-list", "--format=%T", commit.ID.String()).RunInDirPipeline(commit.repo.Path, revListWriter, &stderr)
+		if err != nil {
+			_ = revListWriter.CloseWithError(ConcatenateError(err, (&stderr).String()))
+		} else {
+			_ = revListWriter.Close()
+		}
+	}()
+
+	// We feed the commits in order into cat-file --batch, followed by their trees and sub trees as necessary.
+	// so let's create a batch stdin and stdout
+	batchStdinReader, batchStdinWriter := io.Pipe()
+	batchStdoutReader, batchStdoutWriter := io.Pipe()
+	defer func() {
+		_ = batchStdinReader.Close()
+		_ = batchStdinWriter.Close()
+		_ = batchStdoutReader.Close()
+		_ = batchStdoutWriter.Close()
+	}()
+
+	go func() {
+		stderr := strings.Builder{}
+		err := NewCommand("cat-file", "--batch").RunInDirFullPipeline(commit.repo.Path, batchStdoutWriter, &stderr, batchStdinReader)
+		if err != nil {
+			_ = revListWriter.CloseWithError(ConcatenateError(err, (&stderr).String()))
+		} else {
+			_ = revListWriter.Close()
+		}
+	}()
+
+	// For simplicities sake we'll us a buffered reader
+	batchReader := bufio.NewReader(batchStdoutReader)
+
+	mapsize := 4096
+	if len(paths) > mapsize {
+		mapsize = len(paths)
+	}
+
+	path2idx := make(map[string]int, mapsize)
+	for i, path := range paths {
+		path2idx[path] = i
+	}
+
+	fnameBuf := make([]byte, 4096)
+	modeBuf := make([]byte, 40)
+
+	allShaBuf := make([]byte, (len(paths)+1)*20)
+	shaBuf := make([]byte, 20)
+	tmpTreeID := make([]byte, 40)
+
+	// commits is the returnable commits matching the paths provided
+	commits := make([]string, len(paths))
+	// ids are the blob/tree ids for the paths
+	ids := make([][]byte, len(paths))
+
+	// We'll use a scanner for the revList because it's simpler than a bufio.Reader
+	scan := bufio.NewScanner(revListReader)
+revListLoop:
+	for scan.Scan() {
+		// Get the next parent commit ID
+		commitID := scan.Text()
+		if !scan.Scan() {
+			break revListLoop
+		}
+		commitID = commitID[7:]
+		rootTreeID := scan.Text()
+
+		// push the tree to the cat-file --batch process
+		_, err := batchStdinWriter.Write([]byte(rootTreeID + "\n"))
+		if err != nil {
+			return nil, err
+		}
+
+		currentPath := ""
+
+		// OK if the target tree path is "" and the "" is in the paths just set this now
+		if treePath == "" && paths[0] == "" {
+			// If this is the first time we see this set the id appropriate for this paths to this tree and set the last commit to curCommit
+			if len(ids[0]) == 0 {
+				ids[0] = []byte(rootTreeID)
+				commits[0] = string(commitID)
+			} else if bytes.Equal(ids[0], []byte(rootTreeID)) {
+				commits[0] = string(commitID)
+			}
+		}
+
+	treeReadingLoop:
+		for {
+			_, _, size, err := ReadBatchLine(batchReader)
+			if err != nil {
+				return nil, err
+			}
+
+			// Handle trees
+
+			// n is counter for file position in the tree file
+			var n int64
+
+			// Two options: currentPath is the targetTreepath
+			if treePath == currentPath {
+				// We are in the right directory
+				// Parse each tree line in turn. (don't care about mode here.)
+				for n < size {
+					fname, sha, count, err := ParseTreeLineSkipMode(batchReader, fnameBuf, shaBuf)
+					shaBuf = sha
+					if err != nil {
+						return nil, err
+					}
+					n += int64(count)
+					idx, ok := path2idx[string(fname)]
+					if ok {
+						// Now if this is the first time round set the initial Blob(ish) SHA ID and the commit
+						if len(ids[idx]) == 0 {
+							copy(allShaBuf[20*(idx+1):20*(idx+2)], shaBuf)
+							ids[idx] = allShaBuf[20*(idx+1) : 20*(idx+2)]
+							commits[idx] = string(commitID)
+						} else if bytes.Equal(ids[idx], shaBuf) {
+							commits[idx] = string(commitID)
+						}
+					}
+					// FIXME: is there any order to the way strings are emitted from cat-file?
+					// if there is - then we could skip once we've passed all of our data
+				}
+				break treeReadingLoop
+			}
+
+			var treeID []byte
+
+			// We're in the wrong directory
+			// Find target directory in this directory
+			idx := len(currentPath)
+			if idx > 0 {
+				idx++
+			}
+			target := strings.SplitN(treePath[idx:], "/", 2)[0]
+
+			for n < size {
+				// Read each tree entry in turn
+				mode, fname, sha, count, err := ParseTreeLine(batchReader, modeBuf, fnameBuf, shaBuf)
+				if err != nil {
+					return nil, err
+				}
+				n += int64(count)
+
+				// if we have found the target directory
+				if bytes.Equal(fname, []byte(target)) && bytes.Equal(mode, []byte("40000")) {
+					copy(tmpTreeID, sha)
+					treeID = tmpTreeID
+					break
+				}
+			}
+
+			if n < size {
+				// Discard any remaining entries in the current tree
+				discard := size - n
+				for discard > math.MaxInt32 {
+					_, err := batchReader.Discard(math.MaxInt32)
+					if err != nil {
+						return nil, err
+					}
+					discard -= math.MaxInt32
+				}
+				_, err := batchReader.Discard(int(discard))
+				if err != nil {
+					return nil, err
+				}
+			}
+
+			// if we haven't found a treeID for the target directory our search is over
+			if len(treeID) == 0 {
+				break treeReadingLoop
+			}
+
+			// add the target to the current path
+			if idx > 0 {
+				currentPath += "/"
+			}
+			currentPath += target
+
+			// if we've now found the current path check its sha id and commit status
+			if treePath == currentPath && paths[0] == "" {
+				if len(ids[0]) == 0 {
+					copy(allShaBuf[0:20], treeID)
+					ids[0] = allShaBuf[0:20]
+					commits[0] = string(commitID)
+				} else if bytes.Equal(ids[0], treeID) {
+					commits[0] = string(commitID)
+				}
+			}
+			treeID = to40ByteSHA(treeID)
+			_, err = batchStdinWriter.Write(treeID)
+			if err != nil {
+				return nil, err
+			}
+			_, err = batchStdinWriter.Write([]byte("\n"))
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	commitsMap := make(map[string]*Commit, len(commits))
+	commitsMap[commit.ID.String()] = commit
+
+	commitCommits := make([]*Commit, len(commits))
+	for i, commitID := range commits {
+		c, ok := commitsMap[commitID]
+		if ok {
+			commitCommits[i] = c
+			continue
+		}
+
+		if len(commitID) == 0 {
+			continue
+		}
+
+		_, err := batchStdinWriter.Write([]byte(commitID + "\n"))
+		if err != nil {
+			return nil, err
+		}
+		_, typ, size, err := ReadBatchLine(batchReader)
+		if err != nil {
+			return nil, err
+		}
+		if typ != "commit" {
+			return nil, fmt.Errorf("unexpected type: %s for commit id: %s", typ, commitID)
+		}
+		c, err = CommitFromReader(commit.repo, MustIDFromString(string(commitID)), io.LimitReader(batchReader, int64(size)))
+		if err != nil {
+			return nil, err
+		}
+		commitCommits[i] = c
+	}
+
+	return commitCommits, scan.Err()
+}