1 #include "cache.h"
2 #include "default.h"
3 #include "../commit.h"
4 #include "../fetch-negotiator.h"
5 #include "../prio-queue.h"
6 #include "../refs.h"
7 #include "../tag.h"
8
9 /* Remember to update object flag allocation in object.h */
10 #define COMMON (1U << 2)
11 #define COMMON_REF (1U << 3)
12 #define SEEN (1U << 4)
13 #define POPPED (1U << 5)
14
15 static int marked;
16
17 struct negotiation_state {
18 struct prio_queue rev_list;
19 int non_common_revs;
20 };
21
rev_list_push(struct negotiation_state * ns,struct commit * commit,int mark)22 static void rev_list_push(struct negotiation_state *ns,
23 struct commit *commit, int mark)
24 {
25 if (!(commit->object.flags & mark)) {
26 commit->object.flags |= mark;
27
28 if (parse_commit(commit))
29 return;
30
31 prio_queue_put(&ns->rev_list, commit);
32
33 if (!(commit->object.flags & COMMON))
34 ns->non_common_revs++;
35 }
36 }
37
clear_marks(const char * refname,const struct object_id * oid,int flag,void * cb_data)38 static int clear_marks(const char *refname, const struct object_id *oid,
39 int flag, void *cb_data)
40 {
41 struct object *o = deref_tag(the_repository, parse_object(the_repository, oid), refname, 0);
42
43 if (o && o->type == OBJ_COMMIT)
44 clear_commit_marks((struct commit *)o,
45 COMMON | COMMON_REF | SEEN | POPPED);
46 return 0;
47 }
48
49 /*
50 * This function marks a rev and its ancestors as common.
51 * In some cases, it is desirable to mark only the ancestors (for example
52 * when only the server does not yet know that they are common).
53 */
mark_common(struct negotiation_state * ns,struct commit * commit,int ancestors_only,int dont_parse)54 static void mark_common(struct negotiation_state *ns, struct commit *commit,
55 int ancestors_only, int dont_parse)
56 {
57 if (commit != NULL && !(commit->object.flags & COMMON)) {
58 struct object *o = (struct object *)commit;
59
60 if (!ancestors_only)
61 o->flags |= COMMON;
62
63 if (!(o->flags & SEEN))
64 rev_list_push(ns, commit, SEEN);
65 else {
66 struct commit_list *parents;
67
68 if (!ancestors_only && !(o->flags & POPPED))
69 ns->non_common_revs--;
70 if (!o->parsed && !dont_parse)
71 if (parse_commit(commit))
72 return;
73
74 for (parents = commit->parents;
75 parents;
76 parents = parents->next)
77 mark_common(ns, parents->item, 0,
78 dont_parse);
79 }
80 }
81 }
82
83 /*
84 * Get the next rev to send, ignoring the common.
85 */
get_rev(struct negotiation_state * ns)86 static const struct object_id *get_rev(struct negotiation_state *ns)
87 {
88 struct commit *commit = NULL;
89
90 while (commit == NULL) {
91 unsigned int mark;
92 struct commit_list *parents;
93
94 if (ns->rev_list.nr == 0 || ns->non_common_revs == 0)
95 return NULL;
96
97 commit = prio_queue_get(&ns->rev_list);
98 parse_commit(commit);
99 parents = commit->parents;
100
101 commit->object.flags |= POPPED;
102 if (!(commit->object.flags & COMMON))
103 ns->non_common_revs--;
104
105 if (commit->object.flags & COMMON) {
106 /* do not send "have", and ignore ancestors */
107 commit = NULL;
108 mark = COMMON | SEEN;
109 } else if (commit->object.flags & COMMON_REF)
110 /* send "have", and ignore ancestors */
111 mark = COMMON | SEEN;
112 else
113 /* send "have", also for its ancestors */
114 mark = SEEN;
115
116 while (parents) {
117 if (!(parents->item->object.flags & SEEN))
118 rev_list_push(ns, parents->item, mark);
119 if (mark & COMMON)
120 mark_common(ns, parents->item, 1, 0);
121 parents = parents->next;
122 }
123 }
124
125 return &commit->object.oid;
126 }
127
known_common(struct fetch_negotiator * n,struct commit * c)128 static void known_common(struct fetch_negotiator *n, struct commit *c)
129 {
130 if (!(c->object.flags & SEEN)) {
131 rev_list_push(n->data, c, COMMON_REF | SEEN);
132 mark_common(n->data, c, 1, 1);
133 }
134 }
135
add_tip(struct fetch_negotiator * n,struct commit * c)136 static void add_tip(struct fetch_negotiator *n, struct commit *c)
137 {
138 n->known_common = NULL;
139 rev_list_push(n->data, c, SEEN);
140 }
141
next(struct fetch_negotiator * n)142 static const struct object_id *next(struct fetch_negotiator *n)
143 {
144 n->known_common = NULL;
145 n->add_tip = NULL;
146 return get_rev(n->data);
147 }
148
ack(struct fetch_negotiator * n,struct commit * c)149 static int ack(struct fetch_negotiator *n, struct commit *c)
150 {
151 int known_to_be_common = !!(c->object.flags & COMMON);
152 mark_common(n->data, c, 0, 1);
153 return known_to_be_common;
154 }
155
release(struct fetch_negotiator * n)156 static void release(struct fetch_negotiator *n)
157 {
158 clear_prio_queue(&((struct negotiation_state *)n->data)->rev_list);
159 FREE_AND_NULL(n->data);
160 }
161
default_negotiator_init(struct fetch_negotiator * negotiator)162 void default_negotiator_init(struct fetch_negotiator *negotiator)
163 {
164 struct negotiation_state *ns;
165 negotiator->known_common = known_common;
166 negotiator->add_tip = add_tip;
167 negotiator->next = next;
168 negotiator->ack = ack;
169 negotiator->release = release;
170 negotiator->data = CALLOC_ARRAY(ns, 1);
171 ns->rev_list.compare = compare_commits_by_commit_date;
172
173 if (marked)
174 for_each_ref(clear_marks, NULL);
175 marked = 1;
176 }
177