Merge branch 'aw/gc-lockfile-fscanf-fix' into maint
[git/git.git] / builtin / gc.c
CommitLineData
6757ada4
JB
1/*
2 * git gc builtin command
3 *
4 * Cleanup unreachable files and optimize the repository.
5 *
6 * Copyright (c) 2007 James Bowes
7 *
8 * Based on git-gc.sh, which is
9 *
10 * Copyright (c) 2006 Shawn O. Pearce
11 */
12
baffc0e7 13#include "builtin.h"
b2141fc1 14#include "config.h"
ebebeaea 15#include "tempfile.h"
697cc8ef 16#include "lockfile.h"
44c637c8 17#include "parse-options.h"
6757ada4 18#include "run-command.h"
4c5baf02 19#include "sigchain.h"
234587fc 20#include "argv-array.h"
eab3296c 21#include "commit.h"
6757ada4
JB
22
23#define FAILED_RUN "failed to run %s"
24
44c637c8 25static const char * const builtin_gc_usage[] = {
9c9b4f2f 26 N_("git gc [<options>]"),
44c637c8
JB
27 NULL
28};
6757ada4 29
56752391 30static int pack_refs = 1;
62aad184 31static int prune_reflogs = 1;
07e7dbf0 32static int aggressive_depth = 50;
1c192f34 33static int aggressive_window = 250;
2c3c4399 34static int gc_auto_threshold = 6700;
97063974 35static int gc_auto_pack_limit = 50;
9f673f94 36static int detach_auto = 1;
dddbad72 37static timestamp_t gc_log_expire_time;
a831c06a 38static const char *gc_log_expire = "1.day.ago";
d3154b44 39static const char *prune_expire = "2.weeks.ago";
e3df33bb 40static const char *prune_worktrees_expire = "3.months.ago";
6757ada4 41
234587fc
JK
42static struct argv_array pack_refs_cmd = ARGV_ARRAY_INIT;
43static struct argv_array reflog = ARGV_ARRAY_INIT;
44static struct argv_array repack = ARGV_ARRAY_INIT;
45static struct argv_array prune = ARGV_ARRAY_INIT;
e3df33bb 46static struct argv_array prune_worktrees = ARGV_ARRAY_INIT;
234587fc 47static struct argv_array rerere = ARGV_ARRAY_INIT;
6757ada4 48
ebebeaea 49static struct tempfile pidfile;
329e6e87 50static struct lock_file log_lock;
4c5baf02 51
478f34d2
DK
52static struct string_list pack_garbage = STRING_LIST_INIT_DUP;
53
54static void clean_pack_garbage(void)
55{
56 int i;
57 for (i = 0; i < pack_garbage.nr; i++)
58 unlink_or_warn(pack_garbage.items[i].string);
59 string_list_clear(&pack_garbage, 0);
60}
61
62static void report_pack_garbage(unsigned seen_bits, const char *path)
63{
64 if (seen_bits == PACKDIR_FILE_IDX)
65 string_list_append(&pack_garbage, path);
66}
67
329e6e87
NTND
68static void process_log_file(void)
69{
70 struct stat st;
a831c06a
DT
71 if (fstat(get_lock_file_fd(&log_lock), &st)) {
72 /*
73 * Perhaps there was an i/o error or another
74 * unlikely situation. Try to make a note of
75 * this in gc.log along with any existing
76 * messages.
77 */
78 int saved_errno = errno;
79 fprintf(stderr, _("Failed to fstat %s: %s"),
80 get_tempfile_path(&log_lock.tempfile),
81 strerror(saved_errno));
82 fflush(stderr);
329e6e87 83 commit_lock_file(&log_lock);
a831c06a
DT
84 errno = saved_errno;
85 } else if (st.st_size) {
86 /* There was some error recorded in the lock file */
87 commit_lock_file(&log_lock);
88 } else {
89 /* No error, clean up any old gc.log */
90 unlink(git_path("gc.log"));
329e6e87 91 rollback_lock_file(&log_lock);
a831c06a 92 }
329e6e87
NTND
93}
94
95static void process_log_file_at_exit(void)
96{
97 fflush(stderr);
98 process_log_file();
99}
100
101static void process_log_file_on_signal(int signo)
102{
103 process_log_file();
104 sigchain_pop(signo);
105 raise(signo);
106}
107
5801d3b4 108static void gc_config(void)
6757ada4 109{
5801d3b4
TA
110 const char *value;
111
112 if (!git_config_get_value("gc.packrefs", &value)) {
c5e5a2c0 113 if (value && !strcmp(value, "notbare"))
6757ada4
JB
114 pack_refs = -1;
115 else
5801d3b4 116 pack_refs = git_config_bool("gc.packrefs", value);
17815501 117 }
5801d3b4
TA
118
119 git_config_get_int("gc.aggressivewindow", &aggressive_window);
120 git_config_get_int("gc.aggressivedepth", &aggressive_depth);
121 git_config_get_int("gc.auto", &gc_auto_threshold);
122 git_config_get_int("gc.autopacklimit", &gc_auto_pack_limit);
123 git_config_get_bool("gc.autodetach", &detach_auto);
77d67977
CC
124 git_config_get_expiry("gc.pruneexpire", &prune_expire);
125 git_config_get_expiry("gc.worktreepruneexpire", &prune_worktrees_expire);
94c9b5af 126 git_config_get_expiry("gc.logexpiry", &gc_log_expire);
a831c06a 127
5801d3b4 128 git_config(git_default_config, NULL);
6757ada4
JB
129}
130
a087cc98 131static int too_many_loose_objects(void)
2c3c4399
JH
132{
133 /*
134 * Quickly check if a "gc" is needed, by estimating how
135 * many loose objects there are. Because SHA-1 is evenly
136 * distributed, we can check only one and get a reasonable
137 * estimate.
138 */
2c3c4399
JH
139 DIR *dir;
140 struct dirent *ent;
141 int auto_threshold;
142 int num_loose = 0;
143 int needed = 0;
144
17815501
JH
145 if (gc_auto_threshold <= 0)
146 return 0;
147
07af8891 148 dir = opendir(git_path("objects/17"));
2c3c4399
JH
149 if (!dir)
150 return 0;
151
42c78a21 152 auto_threshold = DIV_ROUND_UP(gc_auto_threshold, 256);
2c3c4399
JH
153 while ((ent = readdir(dir)) != NULL) {
154 if (strspn(ent->d_name, "0123456789abcdef") != 38 ||
155 ent->d_name[38] != '\0')
156 continue;
157 if (++num_loose > auto_threshold) {
158 needed = 1;
159 break;
160 }
161 }
162 closedir(dir);
163 return needed;
164}
165
17815501
JH
166static int too_many_packs(void)
167{
168 struct packed_git *p;
169 int cnt;
170
171 if (gc_auto_pack_limit <= 0)
172 return 0;
173
174 prepare_packed_git();
175 for (cnt = 0, p = packed_git; p; p = p->next) {
17815501
JH
176 if (!p->pack_local)
177 continue;
01af249f 178 if (p->pack_keep)
17815501
JH
179 continue;
180 /*
181 * Perhaps check the size of the pack and count only
182 * very small ones here?
183 */
184 cnt++;
185 }
5f4e3bf5 186 return gc_auto_pack_limit < cnt;
17815501
JH
187}
188
7e52f566
JK
189static void add_repack_all_option(void)
190{
191 if (prune_expire && !strcmp(prune_expire, "now"))
234587fc 192 argv_array_push(&repack, "-a");
7e52f566 193 else {
234587fc
JK
194 argv_array_push(&repack, "-A");
195 if (prune_expire)
196 argv_array_pushf(&repack, "--unpack-unreachable=%s", prune_expire);
7e52f566
JK
197 }
198}
199
bdf56de8
DT
200static void add_repack_incremental_option(void)
201{
202 argv_array_push(&repack, "--no-write-bitmap-index");
203}
204
a087cc98
JH
205static int need_to_gc(void)
206{
207 /*
b14d255b
BC
208 * Setting gc.auto to 0 or negative can disable the
209 * automatic gc.
a087cc98 210 */
b14d255b 211 if (gc_auto_threshold <= 0)
95143f9e
JH
212 return 0;
213
17815501
JH
214 /*
215 * If there are too many loose objects, but not too many
216 * packs, we run "repack -d -l". If there are too many packs,
217 * we run "repack -A -d -l". Otherwise we tell the caller
218 * there is no need.
219 */
17815501 220 if (too_many_packs())
7e52f566 221 add_repack_all_option();
bdf56de8
DT
222 else if (too_many_loose_objects())
223 add_repack_incremental_option();
224 else
17815501 225 return 0;
bde30540 226
15048f8a 227 if (run_hook_le(NULL, "pre-auto-gc", NULL))
bde30540 228 return 0;
95143f9e 229 return 1;
a087cc98
JH
230}
231
64a99eb4
NTND
232/* return NULL on success, else hostname running the gc */
233static const char *lock_repo_for_gc(int force, pid_t* ret_pid)
234{
235 static struct lock_file lock;
da25bdb7 236 char my_host[HOST_NAME_MAX + 1];
64a99eb4
NTND
237 struct strbuf sb = STRBUF_INIT;
238 struct stat st;
239 uintmax_t pid;
240 FILE *fp;
4f1c0b21 241 int fd;
00539cef 242 char *pidfile_path;
64a99eb4 243
ebebeaea 244 if (is_tempfile_active(&pidfile))
4c5baf02
JN
245 /* already locked */
246 return NULL;
247
5781a9a2 248 if (xgethostname(my_host, sizeof(my_host)))
5096d490 249 xsnprintf(my_host, sizeof(my_host), "unknown");
64a99eb4 250
00539cef
MH
251 pidfile_path = git_pathdup("gc.pid");
252 fd = hold_lock_file_for_update(&lock, pidfile_path,
64a99eb4
NTND
253 LOCK_DIE_ON_ERROR);
254 if (!force) {
da25bdb7
RS
255 static char locking_host[HOST_NAME_MAX + 1];
256 static char *scan_fmt;
4f1c0b21 257 int should_exit;
da25bdb7
RS
258
259 if (!scan_fmt)
afe2fab7 260 scan_fmt = xstrfmt("%s %%%ds", "%"SCNuMAX, HOST_NAME_MAX);
00539cef 261 fp = fopen(pidfile_path, "r");
64a99eb4
NTND
262 memset(locking_host, 0, sizeof(locking_host));
263 should_exit =
264 fp != NULL &&
265 !fstat(fileno(fp), &st) &&
266 /*
267 * 12 hour limit is very generous as gc should
268 * never take that long. On the other hand we
269 * don't really need a strict limit here,
270 * running gc --auto one day late is not a big
271 * problem. --force can be used in manual gc
272 * after the user verifies that no gc is
273 * running.
274 */
275 time(NULL) - st.st_mtime <= 12 * 3600 &&
da25bdb7 276 fscanf(fp, scan_fmt, &pid, locking_host) == 2 &&
64a99eb4 277 /* be gentle to concurrent "gc" on remote hosts */
ed7eda8b 278 (strcmp(locking_host, my_host) || !kill(pid, 0) || errno == EPERM);
64a99eb4
NTND
279 if (fp != NULL)
280 fclose(fp);
281 if (should_exit) {
282 if (fd >= 0)
283 rollback_lock_file(&lock);
284 *ret_pid = pid;
00539cef 285 free(pidfile_path);
64a99eb4
NTND
286 return locking_host;
287 }
288 }
289
290 strbuf_addf(&sb, "%"PRIuMAX" %s",
291 (uintmax_t) getpid(), my_host);
292 write_in_full(fd, sb.buf, sb.len);
293 strbuf_release(&sb);
294 commit_lock_file(&lock);
ebebeaea
MH
295 register_tempfile(&pidfile, pidfile_path);
296 free(pidfile_path);
64a99eb4
NTND
297 return NULL;
298}
299
329e6e87
NTND
300static int report_last_gc_error(void)
301{
302 struct strbuf sb = STRBUF_INIT;
a831c06a
DT
303 int ret = 0;
304 struct stat st;
305 char *gc_log_path = git_pathdup("gc.log");
329e6e87 306
a831c06a
DT
307 if (stat(gc_log_path, &st)) {
308 if (errno == ENOENT)
309 goto done;
310
311 ret = error_errno(_("Can't stat %s"), gc_log_path);
312 goto done;
313 }
314
315 if (st.st_mtime < gc_log_expire_time)
316 goto done;
317
318 ret = strbuf_read_file(&sb, gc_log_path, 0);
329e6e87 319 if (ret > 0)
a831c06a 320 ret = error(_("The last gc run reported the following. "
329e6e87
NTND
321 "Please correct the root cause\n"
322 "and remove %s.\n"
323 "Automatic cleanup will not be performed "
324 "until the file is removed.\n\n"
325 "%s"),
a831c06a 326 gc_log_path, sb.buf);
329e6e87 327 strbuf_release(&sb);
a831c06a
DT
328done:
329 free(gc_log_path);
330 return ret;
329e6e87
NTND
331}
332
62aad184
NTND
333static int gc_before_repack(void)
334{
335 if (pack_refs && run_command_v_opt(pack_refs_cmd.argv, RUN_GIT_CMD))
336 return error(FAILED_RUN, pack_refs_cmd.argv[0]);
337
338 if (prune_reflogs && run_command_v_opt(reflog.argv, RUN_GIT_CMD))
339 return error(FAILED_RUN, reflog.argv[0]);
340
341 pack_refs = 0;
342 prune_reflogs = 0;
343 return 0;
344}
345
6757ada4
JB
346int cmd_gc(int argc, const char **argv, const char *prefix)
347{
44c637c8 348 int aggressive = 0;
2c3c4399 349 int auto_gc = 0;
a0c14cbb 350 int quiet = 0;
64a99eb4
NTND
351 int force = 0;
352 const char *name;
353 pid_t pid;
329e6e87 354 int daemonized = 0;
6757ada4 355
44c637c8 356 struct option builtin_gc_options[] = {
6705c162
NTND
357 OPT__QUIET(&quiet, N_("suppress progress reporting")),
358 { OPTION_STRING, 0, "prune", &prune_expire, N_("date"),
359 N_("prune unreferenced objects"),
58e9d9d4 360 PARSE_OPT_OPTARG, NULL, (intptr_t)prune_expire },
d5d09d47
SB
361 OPT_BOOL(0, "aggressive", &aggressive, N_("be more thorough (increased runtime)")),
362 OPT_BOOL(0, "auto", &auto_gc, N_("enable auto-gc mode")),
64a99eb4 363 OPT_BOOL(0, "force", &force, N_("force running gc even if there may be another gc running")),
44c637c8
JB
364 OPT_END()
365 };
366
0c8151b6
NTND
367 if (argc == 2 && !strcmp(argv[1], "-h"))
368 usage_with_options(builtin_gc_usage, builtin_gc_options);
369
234587fc
JK
370 argv_array_pushl(&pack_refs_cmd, "pack-refs", "--all", "--prune", NULL);
371 argv_array_pushl(&reflog, "reflog", "expire", "--all", NULL);
372 argv_array_pushl(&repack, "repack", "-d", "-l", NULL);
2cfe2a78 373 argv_array_pushl(&prune, "prune", "--expire", NULL);
df0b6cfb 374 argv_array_pushl(&prune_worktrees, "worktree", "prune", "--expire", NULL);
234587fc
JK
375 argv_array_pushl(&rerere, "rerere", "gc", NULL);
376
a831c06a 377 /* default expiry time, overwritten in gc_config */
5801d3b4 378 gc_config();
a831c06a
DT
379 if (parse_expiry_date(gc_log_expire, &gc_log_expire_time))
380 die(_("Failed to parse gc.logexpiry value %s"), gc_log_expire);
6757ada4
JB
381
382 if (pack_refs < 0)
383 pack_refs = !is_bare_repository();
384
37782920
SB
385 argc = parse_options(argc, argv, prefix, builtin_gc_options,
386 builtin_gc_usage, 0);
44c637c8
JB
387 if (argc > 0)
388 usage_with_options(builtin_gc_usage, builtin_gc_options);
389
390 if (aggressive) {
234587fc 391 argv_array_push(&repack, "-f");
125f8146
NTND
392 if (aggressive_depth > 0)
393 argv_array_pushf(&repack, "--depth=%d", aggressive_depth);
234587fc
JK
394 if (aggressive_window > 0)
395 argv_array_pushf(&repack, "--window=%d", aggressive_window);
6757ada4 396 }
a0c14cbb 397 if (quiet)
234587fc 398 argv_array_push(&repack, "-q");
6757ada4 399
2c3c4399
JH
400 if (auto_gc) {
401 /*
402 * Auto-gc should be least intrusive as possible.
403 */
2c3c4399
JH
404 if (!need_to_gc())
405 return 0;
9f673f94
NTND
406 if (!quiet) {
407 if (detach_auto)
408 fprintf(stderr, _("Auto packing the repository in background for optimum performance.\n"));
409 else
410 fprintf(stderr, _("Auto packing the repository for optimum performance.\n"));
411 fprintf(stderr, _("See \"git help gc\" for manual housekeeping.\n"));
412 }
62aad184 413 if (detach_auto) {
329e6e87
NTND
414 if (report_last_gc_error())
415 return -1;
416
c45af94d
JK
417 if (lock_repo_for_gc(force, &pid))
418 return 0;
62aad184
NTND
419 if (gc_before_repack())
420 return -1;
c45af94d
JK
421 delete_tempfile(&pidfile);
422
9f673f94
NTND
423 /*
424 * failure to daemonize is ok, we'll continue
425 * in foreground
426 */
329e6e87 427 daemonized = !daemonize();
62aad184 428 }
a37cce3b 429 } else
7e52f566 430 add_repack_all_option();
2c3c4399 431
64a99eb4
NTND
432 name = lock_repo_for_gc(force, &pid);
433 if (name) {
434 if (auto_gc)
435 return 0; /* be quiet on --auto */
436 die(_("gc is already running on machine '%s' pid %"PRIuMAX" (use --force if not)"),
437 name, (uintmax_t)pid);
438 }
439
329e6e87
NTND
440 if (daemonized) {
441 hold_lock_file_for_update(&log_lock,
442 git_path("gc.log"),
443 LOCK_DIE_ON_ERROR);
076c8278 444 dup2(get_lock_file_fd(&log_lock), 2);
329e6e87
NTND
445 sigchain_push_common(process_log_file_on_signal);
446 atexit(process_log_file_at_exit);
447 }
448
62aad184
NTND
449 if (gc_before_repack())
450 return -1;
6757ada4 451
067fbd41
JK
452 if (!repository_format_precious_objects) {
453 if (run_command_v_opt(repack.argv, RUN_GIT_CMD))
454 return error(FAILED_RUN, repack.argv[0]);
455
456 if (prune_expire) {
457 argv_array_push(&prune, prune_expire);
458 if (quiet)
459 argv_array_push(&prune, "--no-progress");
460 if (run_command_v_opt(prune.argv, RUN_GIT_CMD))
461 return error(FAILED_RUN, prune.argv[0]);
462 }
58e9d9d4 463 }
6757ada4 464
e3df33bb
NTND
465 if (prune_worktrees_expire) {
466 argv_array_push(&prune_worktrees, prune_worktrees_expire);
467 if (run_command_v_opt(prune_worktrees.argv, RUN_GIT_CMD))
468 return error(FAILED_RUN, prune_worktrees.argv[0]);
469 }
470
234587fc
JK
471 if (run_command_v_opt(rerere.argv, RUN_GIT_CMD))
472 return error(FAILED_RUN, rerere.argv[0]);
6757ada4 473
478f34d2
DK
474 report_garbage = report_pack_garbage;
475 reprepare_packed_git();
476 if (pack_garbage.nr > 0)
477 clean_pack_garbage();
478
a087cc98 479 if (auto_gc && too_many_loose_objects())
fea6128b
ÆAB
480 warning(_("There are too many unreachable loose objects; "
481 "run 'git prune' to remove them."));
a087cc98 482
a831c06a
DT
483 if (!daemonized)
484 unlink(git_path("gc.log"));
485
6757ada4
JB
486 return 0;
487}