server-info: stop sorting packs by latest date.
[git/git.git] / server-info.c
CommitLineData
8f3f9b09
JH
1#include "cache.h"
2#include "refs.h"
3#include "object.h"
4#include "commit.h"
b614e3d7 5#include "tag.h"
8f3f9b09
JH
6
7/* refs */
8static FILE *info_ref_fp;
8f3f9b09
JH
9
10static int add_info_ref(const char *path, const unsigned char *sha1)
11{
f6b42a81
JH
12 struct object *o = parse_object(sha1);
13
8f3f9b09 14 fprintf(info_ref_fp, "%s %s\n", sha1_to_hex(sha1), path);
f6b42a81 15 if (o->type == tag_type) {
9534f40b
JH
16 o = deref_tag(o, path, 0);
17 if (o)
18 fprintf(info_ref_fp, "%s %s^{}\n",
19 sha1_to_hex(o->sha1), path);
f6b42a81 20 }
8f3f9b09
JH
21 return 0;
22}
23
24static int update_info_refs(int force)
25{
8f3f9b09
JH
26 char *path0 = strdup(git_path("info/refs"));
27 int len = strlen(path0);
28 char *path1 = xmalloc(len + 2);
29
30 strcpy(path1, path0);
31 strcpy(path1 + len, "+");
32
8f3f9b09
JH
33 safe_create_leading_directories(path0);
34 info_ref_fp = fopen(path1, "w");
35 if (!info_ref_fp)
36 return error("unable to update %s", path0);
37 for_each_ref(add_info_ref);
38 fclose(info_ref_fp);
39 rename(path1, path0);
40 free(path0);
41 free(path1);
42 return 0;
43}
44
45/* packs */
4d8fa916 46static struct pack_info {
8f3f9b09
JH
47 struct packed_git *p;
48 int old_num;
49 int new_num;
50 int nr_alloc;
51 int nr_heads;
52 unsigned char (*head)[20];
8f3f9b09
JH
53} **info;
54static int num_pack;
55static const char *objdir;
56static int objdirlen;
57
58static struct object *parse_object_cheap(const unsigned char *sha1)
59{
60 struct object *o;
61
62 if ((o = parse_object(sha1)) == NULL)
63 return NULL;
64 if (o->type == commit_type) {
65 struct commit *commit = (struct commit *)o;
66 free(commit->buffer);
67 commit->buffer = NULL;
f22ca7c5
RF
68 } else if (o->type == tree_type) {
69 struct tree *tree = (struct tree *)o;
70 struct tree_entry_list *e, *n;
71 for (e = tree->entries; e; e = n) {
72 free(e->name);
73 e->name = NULL;
74 n = e->next;
75 free(e);
76 }
77 tree->entries = NULL;
8f3f9b09
JH
78 }
79 return o;
80}
81
82static struct pack_info *find_pack_by_name(const char *name)
83{
84 int i;
85 for (i = 0; i < num_pack; i++) {
86 struct packed_git *p = info[i]->p;
87 /* skip "/pack/" after ".git/objects" */
88 if (!strcmp(p->pack_name + objdirlen + 6, name))
89 return info[i];
90 }
91 return NULL;
92}
93
94static struct pack_info *find_pack_by_old_num(int old_num)
95{
96 int i;
97 for (i = 0; i < num_pack; i++)
98 if (info[i]->old_num == old_num)
99 return info[i];
100 return NULL;
101}
102
103static int add_head_def(struct pack_info *this, unsigned char *sha1)
104{
105 if (this->nr_alloc <= this->nr_heads) {
106 this->nr_alloc = alloc_nr(this->nr_alloc);
107 this->head = xrealloc(this->head, this->nr_alloc * 20);
108 }
109 memcpy(this->head[this->nr_heads++], sha1, 20);
110 return 0;
111}
112
113/* Returns non-zero when we detect that the info in the
114 * old file is useless.
115 */
116static int parse_pack_def(const char *line, int old_cnt)
117{
118 struct pack_info *i = find_pack_by_name(line + 2);
119 if (i) {
120 i->old_num = old_cnt;
121 return 0;
122 }
123 else {
6f42f89c 124 /* The file describes a pack that is no longer here */
8f3f9b09
JH
125 return 1;
126 }
127}
128
6f42f89c 129/* Returns non-zero when we detect that the info in the old file is useless.
8f3f9b09
JH
130 */
131static int parse_head_def(char *line)
132{
133 unsigned char sha1[20];
134 unsigned long num;
135 char *cp, *ep;
136 struct pack_info *this;
137 struct object *o;
138
139 cp = line + 2;
140 num = strtoul(cp, &ep, 10);
141 if (ep == cp || *ep++ != ' ')
142 return error("invalid input ix %s", line);
143 this = find_pack_by_old_num(num);
144 if (!this)
145 return 1; /* You know the drill. */
146 if (get_sha1_hex(ep, sha1) || ep[40] != ' ')
147 return error("invalid input sha1 %s (%s)", line, ep);
148 if ((o = parse_object_cheap(sha1)) == NULL)
149 return error("no such object: %s", line);
150 return add_head_def(this, sha1);
151}
152
153/* Returns non-zero when we detect that the info in the
154 * old file is useless.
155 */
156static int read_pack_info_file(const char *infofile)
157{
158 FILE *fp;
159 char line[1000];
160 int old_cnt = 0;
161
162 fp = fopen(infofile, "r");
163 if (!fp)
164 return 1; /* nonexisting is not an error. */
165
166 while (fgets(line, sizeof(line), fp)) {
167 int len = strlen(line);
168 if (line[len-1] == '\n')
169 line[len-1] = 0;
170
171 switch (line[0]) {
172 case 'P': /* P name */
173 if (parse_pack_def(line, old_cnt++))
174 goto out_stale;
175 break;
6f42f89c
JH
176 case 'D': /* we used to emit D but that was misguided. */
177 goto out_stale;
8f3f9b09
JH
178 break;
179 case 'T': /* T ix sha1 type */
180 if (parse_head_def(line))
181 goto out_stale;
182 break;
183 default:
184 error("unrecognized: %s", line);
185 break;
186 }
187 }
188 fclose(fp);
189 return 0;
190 out_stale:
191 fclose(fp);
192 return 1;
193}
194
8f3f9b09
JH
195static int compare_info(const void *a_, const void *b_)
196{
197 struct pack_info * const* a = a_;
198 struct pack_info * const* b = b_;
199
200 if (0 <= (*a)->old_num && 0 <= (*b)->old_num)
201 /* Keep the order in the original */
202 return (*a)->old_num - (*b)->old_num;
203 else if (0 <= (*a)->old_num)
204 /* Only A existed in the original so B is obviously newer */
205 return -1;
206 else if (0 <= (*b)->old_num)
207 /* The other way around. */
208 return 1;
209
d5eac498
JH
210 /* then it does not matter but at least keep the comparison stable */
211 return (*a)->p - (*b)->p;
8f3f9b09
JH
212}
213
214static void init_pack_info(const char *infofile, int force)
215{
216 struct packed_git *p;
217 int stale;
218 int i = 0;
8f3f9b09
JH
219
220 objdir = get_object_directory();
221 objdirlen = strlen(objdir);
222
223 prepare_packed_git();
224 for (p = packed_git; p; p = p->next) {
225 /* we ignore things on alternate path since they are
226 * not available to the pullers in general.
227 */
228 if (strncmp(p->pack_name, objdir, objdirlen) ||
229 strncmp(p->pack_name + objdirlen, "/pack/", 6))
230 continue;
231 i++;
232 }
233 num_pack = i;
234 info = xcalloc(num_pack, sizeof(struct pack_info *));
235 for (i = 0, p = packed_git; p; p = p->next) {
236 if (strncmp(p->pack_name, objdir, objdirlen) ||
237 p->pack_name[objdirlen] != '/')
238 continue;
6f42f89c 239 info[i] = xcalloc(1, sizeof(struct pack_info));
8f3f9b09
JH
240 info[i]->p = p;
241 info[i]->old_num = -1;
242 i++;
243 }
244
245 if (infofile && !force)
246 stale = read_pack_info_file(infofile);
247 else
248 stale = 1;
249
250 for (i = 0; i < num_pack; i++) {
251 if (stale) {
252 info[i]->old_num = -1;
8f3f9b09
JH
253 info[i]->nr_heads = 0;
254 }
8f3f9b09
JH
255 }
256
6f42f89c 257 /* renumber them */
8f3f9b09
JH
258 qsort(info, num_pack, sizeof(info[0]), compare_info);
259 for (i = 0; i < num_pack; i++)
260 info[i]->new_num = i;
8f3f9b09
JH
261}
262
263static void write_pack_info_file(FILE *fp)
264{
265 int i, j;
266 for (i = 0; i < num_pack; i++)
267 fprintf(fp, "P %s\n", info[i]->p->pack_name + objdirlen + 6);
8f3f9b09
JH
268 for (i = 0; i < num_pack; i++) {
269 struct pack_info *this = info[i];
270 for (j = 0; j < this->nr_heads; j++) {
271 struct object *o = lookup_object(this->head[j]);
272 fprintf(fp, "T %1d %s %s\n",
273 i, sha1_to_hex(this->head[j]), o->type);
274 }
275 }
276
277}
278
279#define REFERENCED 01
8f3f9b09
JH
280#define EMITTED 04
281
282static void show(struct object *o, int pack_ix)
283{
284 /*
285 * We are interested in objects that are not referenced,
8f3f9b09
JH
286 */
287 if (o->flags & EMITTED)
288 return;
289
290 if (!(o->flags & REFERENCED))
291 add_head_def(info[pack_ix], o->sha1);
8f3f9b09
JH
292 o->flags |= EMITTED;
293}
294
295static void find_pack_info_one(int pack_ix)
296{
297 unsigned char sha1[20];
298 struct object *o;
8f3f9b09
JH
299 int i;
300 struct packed_git *p = info[pack_ix]->p;
301 int num = num_packed_objects(p);
302
303 /* Scan objects, clear flags from all the edge ones and
304 * internal ones, possibly marked in the previous round.
305 */
306 for (i = 0; i < num; i++) {
307 if (nth_packed_object_sha1(p, i, sha1))
308 die("corrupt pack file %s?", p->pack_name);
d5eac498 309 if ((o = parse_object_cheap(sha1)) == NULL)
8f3f9b09 310 die("cannot parse %s", sha1_to_hex(sha1));
4a4e6fd7
SV
311 if (o->refs) {
312 struct object_refs *refs = o->refs;
313 int j;
314 for (j = 0; j < refs->count; j++)
315 refs->ref[j]->flags = 0;
316 }
8f3f9b09
JH
317 o->flags = 0;
318 }
319
6f42f89c 320 /* Mark all the referenced ones */
8f3f9b09
JH
321 for (i = 0; i < num; i++) {
322 if (nth_packed_object_sha1(p, i, sha1))
323 die("corrupt pack file %s?", p->pack_name);
324 if ((o = lookup_object(sha1)) == NULL)
325 die("cannot find %s", sha1_to_hex(sha1));
4a4e6fd7
SV
326 if (o->refs) {
327 struct object_refs *refs = o->refs;
328 int j;
329 for (j = 0; j < refs->count; j++)
330 refs->ref[j]->flags |= REFERENCED;
331 }
8f3f9b09
JH
332 }
333
334 for (i = 0; i < num; i++) {
335 if (nth_packed_object_sha1(p, i, sha1))
336 die("corrupt pack file %s?", p->pack_name);
337 if ((o = lookup_object(sha1)) == NULL)
338 die("cannot find %s", sha1_to_hex(sha1));
8f3f9b09 339 show(o, pack_ix);
8f3f9b09
JH
340 }
341
342}
343
344static void find_pack_info(void)
345{
346 int i;
347 for (i = 0; i < num_pack; i++) {
348 /* The packed objects are cast in stone, and a head
349 * in a pack will stay as head, so is the set of missing
350 * objects. If the repo has been reorganized and we
351 * are missing some packs available back then, we have
352 * already discarded the info read from the file, so
353 * we will find (old_num < 0) in that case.
354 */
355 if (0 <= info[i]->old_num)
356 continue;
357 find_pack_info_one(i);
358 }
359}
360
361static int update_info_packs(int force)
362{
363 char infofile[PATH_MAX];
364 char name[PATH_MAX];
365 int namelen;
366 FILE *fp;
367
368 namelen = sprintf(infofile, "%s/info/packs", get_object_directory());
369 strcpy(name, infofile);
370 strcpy(name + namelen, "+");
371
372 init_pack_info(infofile, force);
373 find_pack_info();
374
375 safe_create_leading_directories(name);
376 fp = fopen(name, "w");
377 if (!fp)
378 return error("cannot open %s", name);
379 write_pack_info_file(fp);
380 fclose(fp);
381 rename(name, infofile);
382 return 0;
383}
384
8f3f9b09
JH
385/* public */
386int update_server_info(int force)
387{
388 /* We would add more dumb-server support files later,
389 * including index of available pack files and their
390 * intended audiences.
391 */
392 int errs = 0;
393
394 errs = errs | update_info_refs(force);
395 errs = errs | update_info_packs(force);
8f3f9b09 396
6f42f89c
JH
397 /* remove leftover rev-cache file if there is any */
398 unlink(git_path("info/rev-cache"));
399
8f3f9b09
JH
400 return errs;
401}