1#include "fetch.h"
2
3#include "cache.h"
4#include "commit.h"
5#include "tree.h"
6#include "tag.h"
7#include "blob.h"
8#include "refs.h"
9
10const char *write_ref = NULL;
11
12const unsigned char *current_ref = NULL;
13
14int get_tree = 0;
15int get_history = 0;
16int get_all = 0;
17int get_verbosely = 0;
18static unsigned char current_commit_sha1[20];
19
20void pull_say(const char *fmt, const char *hex)
21{
22 if (get_verbosely)
23 fprintf(stderr, fmt, hex);
24}
25
26static void report_missing(const char *what, const unsigned char *missing)
27{
28 char missing_hex[41];
29
30 strcpy(missing_hex, sha1_to_hex(missing));;
31 fprintf(stderr,
32 "Cannot obtain needed %s %s\nwhile processing commit %s.\n",
33 what, missing_hex, sha1_to_hex(current_commit_sha1));
34}
35
36static int process(struct object *obj);
37
38static int process_tree(struct tree *tree)
39{
40 struct tree_entry_list *entry;
41
42 if (parse_tree(tree))
43 return -1;
44
45 entry = tree->entries;
46 tree->entries = NULL;
47 while (entry) {
48 struct tree_entry_list *next = entry->next;
49 if (process(entry->item.any))
50 return -1;
51 free(entry);
52 entry = next;
53 }
54 return 0;
55}
56
57#define COMPLETE 1U
58#define TO_FETCH 2U
59#define TO_SCAN 4U
60#define SCANNED 8U
61
62static struct commit_list *complete = NULL;
63
64static int process_commit(struct commit *commit)
65{
66 if (parse_commit(commit))
67 return -1;
68
69 while (complete && complete->item->date >= commit->date) {
70 pop_most_recent_commit(&complete, COMPLETE);
71 }
72
73 if (commit->object.flags & COMPLETE)
74 return 0;
75
76 memcpy(current_commit_sha1, commit->object.sha1, 20);
77
78 pull_say("walk %s\n", sha1_to_hex(commit->object.sha1));
79
80 if (get_tree) {
81 if (process(&commit->tree->object))
82 return -1;
83 if (!get_all)
84 get_tree = 0;
85 }
86 if (get_history) {
87 struct commit_list *parents = commit->parents;
88 for (; parents; parents = parents->next) {
89 if (process(&parents->item->object))
90 return -1;
91 }
92 }
93 return 0;
94}
95
96static int process_tag(struct tag *tag)
97{
98 if (parse_tag(tag))
99 return -1;
100 return process(tag->tagged);
101}
102
103static struct object_list *process_queue = NULL;
104static struct object_list **process_queue_end = &process_queue;
105
106static int process_object(struct object *obj)
107{
108 if (obj->flags & SCANNED)
109 return 0;
110 obj->flags |= SCANNED;
111
112 if (obj->type == commit_type) {
113 if (process_commit((struct commit *)obj))
114 return -1;
115 return 0;
116 }
117 if (obj->type == tree_type) {
118 if (process_tree((struct tree *)obj))
119 return -1;
120 return 0;
121 }
122 if (obj->type == blob_type) {
123 return 0;
124 }
125 if (obj->type == tag_type) {
126 if (process_tag((struct tag *)obj))
127 return -1;
128 return 0;
129 }
130 return error("Unable to determine requirements "
131 "of type %s for %s",
132 obj->type, sha1_to_hex(obj->sha1));
133}
134
135static int process(struct object *obj)
136{
137 if (has_sha1_file(obj->sha1)) {
138 parse_object(obj->sha1);
139 /* We already have it, so we should scan it now. */
140 if (obj->flags & (SCANNED | TO_SCAN))
141 return 0;
142 object_list_insert(obj, process_queue_end);
143 process_queue_end = &(*process_queue_end)->next;
144 obj->flags |= TO_SCAN;
145 return 0;
146 }
147 if (obj->flags & (COMPLETE | TO_FETCH))
148 return 0;
149 object_list_insert(obj, process_queue_end);
150 process_queue_end = &(*process_queue_end)->next;
151 obj->flags |= TO_FETCH;
152
153 prefetch(obj->sha1);
154
155 return 0;
156}
157
158static int loop(void)
159{
160 struct object_list *elem;
161
162 while (process_queue) {
163 struct object *obj = process_queue->item;
164 elem = process_queue;
165 process_queue = elem->next;
166 free(elem);
167 if (!process_queue)
168 process_queue_end = &process_queue;
169
170 /* If we are not scanning this object, we placed it in
171 * the queue because we needed to fetch it first.
172 */
173 if (! (obj->flags & TO_SCAN)) {
174 if (!has_sha1_file(obj->sha1) && fetch(obj->sha1)) {
175 report_missing(obj->type
176 ? obj->type
177 : "object", obj->sha1);
178 return -1;
179 }
180 }
181 if (!obj->type)
182 parse_object(obj->sha1);
183 if (process_object(obj))
184 return -1;
185 }
186 return 0;
187}
188
189static int interpret_target(char *target, unsigned char *sha1)
190{
191 if (!get_sha1_hex(target, sha1))
192 return 0;
193 if (!check_ref_format(target)) {
194 if (!fetch_ref(target, sha1)) {
195 return 0;
196 }
197 }
198 return -1;
199}
200
201static int mark_complete(const char *path, const unsigned char *sha1)
202{
203 struct commit *commit = lookup_commit_reference_gently(sha1, 1);
204 if (commit) {
205 commit->object.flags |= COMPLETE;
206 insert_by_date(commit, &complete);
207 }
208 return 0;
209}
210
211int pull(char *target)
212{
213 unsigned char sha1[20];
214 int fd = -1;
215
216 save_commit_buffer = 0;
217 if (write_ref && current_ref) {
218 fd = lock_ref_sha1(write_ref, current_ref);
219 if (fd < 0)
220 return -1;
221 }
222
223 for_each_ref(mark_complete);
224
225 if (interpret_target(target, sha1))
226 return error("Could not interpret %s as something to pull",
227 target);
228 if (process(lookup_unknown_object(sha1)))
229 return -1;
230 if (loop())
231 return -1;
232
233 if (write_ref) {
234 if (current_ref) {
235 write_ref_sha1(write_ref, fd, sha1);
236 } else {
237 write_ref_sha1_unlocked(write_ref, sha1);
238 }
239 }
240 return 0;
241}