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