forked from src-d/go-git
-
Notifications
You must be signed in to change notification settings - Fork 0
/
revlist.go
218 lines (180 loc) · 4.4 KB
/
revlist.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
// Package revlist provides support to access the ancestors of commits, in a
// similar way as the git-rev-list command.
package revlist
import (
"fmt"
"io"
"gopkg.in/src-d/go-git.v4/plumbing"
"gopkg.in/src-d/go-git.v4/plumbing/filemode"
"gopkg.in/src-d/go-git.v4/plumbing/object"
"gopkg.in/src-d/go-git.v4/plumbing/storer"
)
// Objects applies a complementary set. It gets all the hashes from all
// the reachable objects from the given objects. Ignore param are object hashes
// that we want to ignore on the result. All that objects must be accessible
// from the object storer.
func Objects(
s storer.EncodedObjectStorer,
objs,
ignore []plumbing.Hash,
) ([]plumbing.Hash, error) {
ignore, err := objects(s, ignore, nil, true)
if err != nil {
return nil, err
}
return objects(s, objs, ignore, false)
}
func objects(
s storer.EncodedObjectStorer,
objects,
ignore []plumbing.Hash,
allowMissingObjects bool,
) ([]plumbing.Hash, error) {
seen := hashListToSet(ignore)
result := make(map[plumbing.Hash]bool)
visited := make(map[plumbing.Hash]bool)
walkerFunc := func(h plumbing.Hash) {
if !seen[h] {
result[h] = true
seen[h] = true
}
}
for _, h := range objects {
if err := processObject(s, h, seen, visited, ignore, walkerFunc); err != nil {
if allowMissingObjects && err == plumbing.ErrObjectNotFound {
continue
}
return nil, err
}
}
return hashSetToList(result), nil
}
// processObject obtains the object using the hash an process it depending of its type
func processObject(
s storer.EncodedObjectStorer,
h plumbing.Hash,
seen map[plumbing.Hash]bool,
visited map[plumbing.Hash]bool,
ignore []plumbing.Hash,
walkerFunc func(h plumbing.Hash),
) error {
if seen[h] {
return nil
}
o, err := s.EncodedObject(plumbing.AnyObject, h)
if err != nil {
return err
}
do, err := object.DecodeObject(s, o)
if err != nil {
return err
}
switch do := do.(type) {
case *object.Commit:
return reachableObjects(do, seen, visited, ignore, walkerFunc)
case *object.Tree:
return iterateCommitTrees(seen, do, walkerFunc)
case *object.Tag:
walkerFunc(do.Hash)
return processObject(s, do.Target, seen, visited, ignore, walkerFunc)
case *object.Blob:
walkerFunc(do.Hash)
default:
return fmt.Errorf("object type not valid: %s. "+
"Object reference: %s", o.Type(), o.Hash())
}
return nil
}
// reachableObjects returns, using the callback function, all the reachable
// objects from the specified commit. To avoid to iterate over seen commits,
// if a commit hash is into the 'seen' set, we will not iterate all his trees
// and blobs objects.
func reachableObjects(
commit *object.Commit,
seen map[plumbing.Hash]bool,
visited map[plumbing.Hash]bool,
ignore []plumbing.Hash,
cb func(h plumbing.Hash),
) error {
i := object.NewCommitPreorderIter(commit, seen, ignore)
pending := make(map[plumbing.Hash]bool)
addPendingParents(pending, visited, commit)
for {
commit, err := i.Next()
if err == io.EOF {
break
}
if err != nil {
return err
}
if pending[commit.Hash] {
delete(pending, commit.Hash)
}
addPendingParents(pending, visited, commit)
if visited[commit.Hash] && len(pending) == 0 {
break
}
if seen[commit.Hash] {
continue
}
cb(commit.Hash)
tree, err := commit.Tree()
if err != nil {
return err
}
if err := iterateCommitTrees(seen, tree, cb); err != nil {
return err
}
}
return nil
}
func addPendingParents(pending, visited map[plumbing.Hash]bool, commit *object.Commit) {
for _, p := range commit.ParentHashes {
if !visited[p] {
pending[p] = true
}
}
}
// iterateCommitTrees iterate all reachable trees from the given commit
func iterateCommitTrees(
seen map[plumbing.Hash]bool,
tree *object.Tree,
cb func(h plumbing.Hash),
) error {
if seen[tree.Hash] {
return nil
}
cb(tree.Hash)
treeWalker := object.NewTreeWalker(tree, true, seen)
for {
_, e, err := treeWalker.Next()
if err == io.EOF {
break
}
if err != nil {
return err
}
if e.Mode == filemode.Submodule {
continue
}
if seen[e.Hash] {
continue
}
cb(e.Hash)
}
return nil
}
func hashSetToList(hashes map[plumbing.Hash]bool) []plumbing.Hash {
var result []plumbing.Hash
for key := range hashes {
result = append(result, key)
}
return result
}
func hashListToSet(hashes []plumbing.Hash) map[plumbing.Hash]bool {
result := make(map[plumbing.Hash]bool)
for _, h := range hashes {
result[h] = true
}
return result
}