object-store: move packed_git and packed_git_mru to object store
[git/git.git] / server-info.c
1 #include "cache.h"
2 #include "repository.h"
3 #include "refs.h"
4 #include "object.h"
5 #include "commit.h"
6 #include "tag.h"
7 #include "packfile.h"
8 #include "object-store.h"
9
10 /*
11 * Create the file "path" by writing to a temporary file and renaming
12 * it into place. The contents of the file come from "generate", which
13 * should return non-zero if it encounters an error.
14 */
15 static int update_info_file(char *path, int (*generate)(FILE *))
16 {
17 char *tmp = mkpathdup("%s_XXXXXX", path);
18 int ret = -1;
19 int fd = -1;
20 FILE *fp = NULL, *to_close;
21
22 safe_create_leading_directories(path);
23 fd = git_mkstemp_mode(tmp, 0666);
24 if (fd < 0)
25 goto out;
26 to_close = fp = fdopen(fd, "w");
27 if (!fp)
28 goto out;
29 fd = -1;
30 ret = generate(fp);
31 if (ret)
32 goto out;
33 fp = NULL;
34 if (fclose(to_close))
35 goto out;
36 if (adjust_shared_perm(tmp) < 0)
37 goto out;
38 if (rename(tmp, path) < 0)
39 goto out;
40 ret = 0;
41
42 out:
43 if (ret) {
44 error_errno("unable to update %s", path);
45 if (fp)
46 fclose(fp);
47 else if (fd >= 0)
48 close(fd);
49 unlink(tmp);
50 }
51 free(tmp);
52 return ret;
53 }
54
55 static int add_info_ref(const char *path, const struct object_id *oid,
56 int flag, void *cb_data)
57 {
58 FILE *fp = cb_data;
59 struct object *o = parse_object(oid);
60 if (!o)
61 return -1;
62
63 if (fprintf(fp, "%s %s\n", oid_to_hex(oid), path) < 0)
64 return -1;
65
66 if (o->type == OBJ_TAG) {
67 o = deref_tag(o, path, 0);
68 if (o)
69 if (fprintf(fp, "%s %s^{}\n",
70 oid_to_hex(&o->oid), path) < 0)
71 return -1;
72 }
73 return 0;
74 }
75
76 static int generate_info_refs(FILE *fp)
77 {
78 return for_each_ref(add_info_ref, fp);
79 }
80
81 static int update_info_refs(int force)
82 {
83 char *path = git_pathdup("info/refs");
84 int ret = update_info_file(path, generate_info_refs);
85 free(path);
86 return ret;
87 }
88
89 /* packs */
90 static struct pack_info {
91 struct packed_git *p;
92 int old_num;
93 int new_num;
94 int nr_alloc;
95 int nr_heads;
96 unsigned char (*head)[20];
97 } **info;
98 static int num_pack;
99 static const char *objdir;
100 static int objdirlen;
101
102 static struct pack_info *find_pack_by_name(const char *name)
103 {
104 int i;
105 for (i = 0; i < num_pack; i++) {
106 struct packed_git *p = info[i]->p;
107 /* skip "/pack/" after ".git/objects" */
108 if (!strcmp(p->pack_name + objdirlen + 6, name))
109 return info[i];
110 }
111 return NULL;
112 }
113
114 /* Returns non-zero when we detect that the info in the
115 * old file is useless.
116 */
117 static int parse_pack_def(const char *line, int old_cnt)
118 {
119 struct pack_info *i = find_pack_by_name(line + 2);
120 if (i) {
121 i->old_num = old_cnt;
122 return 0;
123 }
124 else {
125 /* The file describes a pack that is no longer here */
126 return 1;
127 }
128 }
129
130 /* Returns non-zero when we detect that the info in the
131 * old file is useless.
132 */
133 static int read_pack_info_file(const char *infofile)
134 {
135 FILE *fp;
136 char line[1000];
137 int old_cnt = 0;
138
139 fp = fopen_or_warn(infofile, "r");
140 if (!fp)
141 return 1; /* nonexistent is not an error. */
142
143 while (fgets(line, sizeof(line), fp)) {
144 int len = strlen(line);
145 if (len && line[len-1] == '\n')
146 line[--len] = 0;
147
148 if (!len)
149 continue;
150
151 switch (line[0]) {
152 case 'P': /* P name */
153 if (parse_pack_def(line, old_cnt++))
154 goto out_stale;
155 break;
156 case 'D': /* we used to emit D but that was misguided. */
157 case 'T': /* we used to emit T but nobody uses it. */
158 goto out_stale;
159 default:
160 error("unrecognized: %s", line);
161 break;
162 }
163 }
164 fclose(fp);
165 return 0;
166 out_stale:
167 fclose(fp);
168 return 1;
169 }
170
171 static int compare_info(const void *a_, const void *b_)
172 {
173 struct pack_info *const *a = a_;
174 struct pack_info *const *b = b_;
175
176 if (0 <= (*a)->old_num && 0 <= (*b)->old_num)
177 /* Keep the order in the original */
178 return (*a)->old_num - (*b)->old_num;
179 else if (0 <= (*a)->old_num)
180 /* Only A existed in the original so B is obviously newer */
181 return -1;
182 else if (0 <= (*b)->old_num)
183 /* The other way around. */
184 return 1;
185
186 /* then it does not matter but at least keep the comparison stable */
187 if ((*a)->p == (*b)->p)
188 return 0;
189 else if ((*a)->p < (*b)->p)
190 return -1;
191 else
192 return 1;
193 }
194
195 static void init_pack_info(const char *infofile, int force)
196 {
197 struct packed_git *p;
198 int stale;
199 int i = 0;
200
201 objdir = get_object_directory();
202 objdirlen = strlen(objdir);
203
204 prepare_packed_git();
205 for (p = get_packed_git(the_repository); p; p = p->next) {
206 /* we ignore things on alternate path since they are
207 * not available to the pullers in general.
208 */
209 if (!p->pack_local)
210 continue;
211 i++;
212 }
213 num_pack = i;
214 info = xcalloc(num_pack, sizeof(struct pack_info *));
215 for (i = 0, p = get_packed_git(the_repository); p; p = p->next) {
216 if (!p->pack_local)
217 continue;
218 info[i] = xcalloc(1, sizeof(struct pack_info));
219 info[i]->p = p;
220 info[i]->old_num = -1;
221 i++;
222 }
223
224 if (infofile && !force)
225 stale = read_pack_info_file(infofile);
226 else
227 stale = 1;
228
229 for (i = 0; i < num_pack; i++) {
230 if (stale) {
231 info[i]->old_num = -1;
232 info[i]->nr_heads = 0;
233 }
234 }
235
236 /* renumber them */
237 QSORT(info, num_pack, compare_info);
238 for (i = 0; i < num_pack; i++)
239 info[i]->new_num = i;
240 }
241
242 static void free_pack_info(void)
243 {
244 int i;
245 for (i = 0; i < num_pack; i++)
246 free(info[i]);
247 free(info);
248 }
249
250 static int write_pack_info_file(FILE *fp)
251 {
252 int i;
253 for (i = 0; i < num_pack; i++) {
254 if (fprintf(fp, "P %s\n", info[i]->p->pack_name + objdirlen + 6) < 0)
255 return -1;
256 }
257 if (fputc('\n', fp) == EOF)
258 return -1;
259 return 0;
260 }
261
262 static int update_info_packs(int force)
263 {
264 char *infofile = mkpathdup("%s/info/packs", get_object_directory());
265 int ret;
266
267 init_pack_info(infofile, force);
268 ret = update_info_file(infofile, write_pack_info_file);
269 free_pack_info();
270 free(infofile);
271 return ret;
272 }
273
274 /* public */
275 int update_server_info(int force)
276 {
277 /* We would add more dumb-server support files later,
278 * including index of available pack files and their
279 * intended audiences.
280 */
281 int errs = 0;
282
283 errs = errs | update_info_refs(force);
284 errs = errs | update_info_packs(force);
285
286 /* remove leftover rev-cache file if there is any */
287 unlink_or_warn(git_path("info/rev-cache"));
288
289 return errs;
290 }