git-clone.sh: use the $( ... ) construct for command substitution
[git/jrn.git] / builtin / gc.c
blob63d400bcb2092b1751427994b35057f72b04de17
1 /*
2 * git gc builtin command
4 * Cleanup unreachable files and optimize the repository.
6 * Copyright (c) 2007 James Bowes
8 * Based on git-gc.sh, which is
10 * Copyright (c) 2006 Shawn O. Pearce
13 #include "builtin.h"
14 #include "cache.h"
15 #include "parse-options.h"
16 #include "run-command.h"
17 #include "sigchain.h"
18 #include "argv-array.h"
19 #include "commit.h"
21 #define FAILED_RUN "failed to run %s"
23 static const char * const builtin_gc_usage[] = {
24 N_("git gc [options]"),
25 NULL
28 static int pack_refs = 1;
29 static int aggressive_window = 250;
30 static int gc_auto_threshold = 6700;
31 static int gc_auto_pack_limit = 50;
32 static int detach_auto = 1;
33 static const char *prune_expire = "2.weeks.ago";
35 static struct argv_array pack_refs_cmd = ARGV_ARRAY_INIT;
36 static struct argv_array reflog = ARGV_ARRAY_INIT;
37 static struct argv_array repack = ARGV_ARRAY_INIT;
38 static struct argv_array prune = ARGV_ARRAY_INIT;
39 static struct argv_array rerere = ARGV_ARRAY_INIT;
41 static char *pidfile;
43 static void remove_pidfile(void)
45 if (pidfile)
46 unlink(pidfile);
49 static void remove_pidfile_on_signal(int signo)
51 remove_pidfile();
52 sigchain_pop(signo);
53 raise(signo);
56 static int gc_config(const char *var, const char *value, void *cb)
58 if (!strcmp(var, "gc.packrefs")) {
59 if (value && !strcmp(value, "notbare"))
60 pack_refs = -1;
61 else
62 pack_refs = git_config_bool(var, value);
63 return 0;
65 if (!strcmp(var, "gc.aggressivewindow")) {
66 aggressive_window = git_config_int(var, value);
67 return 0;
69 if (!strcmp(var, "gc.auto")) {
70 gc_auto_threshold = git_config_int(var, value);
71 return 0;
73 if (!strcmp(var, "gc.autopacklimit")) {
74 gc_auto_pack_limit = git_config_int(var, value);
75 return 0;
77 if (!strcmp(var, "gc.autodetach")) {
78 detach_auto = git_config_bool(var, value);
79 return 0;
81 if (!strcmp(var, "gc.pruneexpire")) {
82 if (value && strcmp(value, "now")) {
83 unsigned long now = approxidate("now");
84 if (approxidate(value) >= now)
85 return error(_("Invalid %s: '%s'"), var, value);
87 return git_config_string(&prune_expire, var, value);
89 return git_default_config(var, value, cb);
92 static int too_many_loose_objects(void)
95 * Quickly check if a "gc" is needed, by estimating how
96 * many loose objects there are. Because SHA-1 is evenly
97 * distributed, we can check only one and get a reasonable
98 * estimate.
100 char path[PATH_MAX];
101 const char *objdir = get_object_directory();
102 DIR *dir;
103 struct dirent *ent;
104 int auto_threshold;
105 int num_loose = 0;
106 int needed = 0;
108 if (gc_auto_threshold <= 0)
109 return 0;
111 if (sizeof(path) <= snprintf(path, sizeof(path), "%s/17", objdir)) {
112 warning(_("insanely long object directory %.*s"), 50, objdir);
113 return 0;
115 dir = opendir(path);
116 if (!dir)
117 return 0;
119 auto_threshold = (gc_auto_threshold + 255) / 256;
120 while ((ent = readdir(dir)) != NULL) {
121 if (strspn(ent->d_name, "0123456789abcdef") != 38 ||
122 ent->d_name[38] != '\0')
123 continue;
124 if (++num_loose > auto_threshold) {
125 needed = 1;
126 break;
129 closedir(dir);
130 return needed;
133 static int too_many_packs(void)
135 struct packed_git *p;
136 int cnt;
138 if (gc_auto_pack_limit <= 0)
139 return 0;
141 prepare_packed_git();
142 for (cnt = 0, p = packed_git; p; p = p->next) {
143 if (!p->pack_local)
144 continue;
145 if (p->pack_keep)
146 continue;
148 * Perhaps check the size of the pack and count only
149 * very small ones here?
151 cnt++;
153 return gc_auto_pack_limit <= cnt;
156 static void add_repack_all_option(void)
158 if (prune_expire && !strcmp(prune_expire, "now"))
159 argv_array_push(&repack, "-a");
160 else {
161 argv_array_push(&repack, "-A");
162 if (prune_expire)
163 argv_array_pushf(&repack, "--unpack-unreachable=%s", prune_expire);
167 static int need_to_gc(void)
170 * Setting gc.auto to 0 or negative can disable the
171 * automatic gc.
173 if (gc_auto_threshold <= 0)
174 return 0;
177 * If there are too many loose objects, but not too many
178 * packs, we run "repack -d -l". If there are too many packs,
179 * we run "repack -A -d -l". Otherwise we tell the caller
180 * there is no need.
182 if (too_many_packs())
183 add_repack_all_option();
184 else if (!too_many_loose_objects())
185 return 0;
187 if (run_hook(NULL, "pre-auto-gc", NULL))
188 return 0;
189 return 1;
192 /* return NULL on success, else hostname running the gc */
193 static const char *lock_repo_for_gc(int force, pid_t* ret_pid)
195 static struct lock_file lock;
196 char my_host[128];
197 struct strbuf sb = STRBUF_INIT;
198 struct stat st;
199 uintmax_t pid;
200 FILE *fp;
201 int fd;
203 if (pidfile)
204 /* already locked */
205 return NULL;
207 if (gethostname(my_host, sizeof(my_host)))
208 strcpy(my_host, "unknown");
210 fd = hold_lock_file_for_update(&lock, git_path("gc.pid"),
211 LOCK_DIE_ON_ERROR);
212 if (!force) {
213 static char locking_host[128];
214 int should_exit;
215 fp = fopen(git_path("gc.pid"), "r");
216 memset(locking_host, 0, sizeof(locking_host));
217 should_exit =
218 fp != NULL &&
219 !fstat(fileno(fp), &st) &&
221 * 12 hour limit is very generous as gc should
222 * never take that long. On the other hand we
223 * don't really need a strict limit here,
224 * running gc --auto one day late is not a big
225 * problem. --force can be used in manual gc
226 * after the user verifies that no gc is
227 * running.
229 time(NULL) - st.st_mtime <= 12 * 3600 &&
230 fscanf(fp, "%"PRIuMAX" %127c", &pid, locking_host) == 2 &&
231 /* be gentle to concurrent "gc" on remote hosts */
232 (strcmp(locking_host, my_host) || !kill(pid, 0) || errno == EPERM);
233 if (fp != NULL)
234 fclose(fp);
235 if (should_exit) {
236 if (fd >= 0)
237 rollback_lock_file(&lock);
238 *ret_pid = pid;
239 return locking_host;
243 strbuf_addf(&sb, "%"PRIuMAX" %s",
244 (uintmax_t) getpid(), my_host);
245 write_in_full(fd, sb.buf, sb.len);
246 strbuf_release(&sb);
247 commit_lock_file(&lock);
249 pidfile = git_pathdup("gc.pid");
250 sigchain_push_common(remove_pidfile_on_signal);
251 atexit(remove_pidfile);
253 return NULL;
256 int cmd_gc(int argc, const char **argv, const char *prefix)
258 int aggressive = 0;
259 int auto_gc = 0;
260 int quiet = 0;
261 int force = 0;
262 const char *name;
263 pid_t pid;
265 struct option builtin_gc_options[] = {
266 OPT__QUIET(&quiet, N_("suppress progress reporting")),
267 { OPTION_STRING, 0, "prune", &prune_expire, N_("date"),
268 N_("prune unreferenced objects"),
269 PARSE_OPT_OPTARG, NULL, (intptr_t)prune_expire },
270 OPT_BOOL(0, "aggressive", &aggressive, N_("be more thorough (increased runtime)")),
271 OPT_BOOL(0, "auto", &auto_gc, N_("enable auto-gc mode")),
272 OPT_BOOL(0, "force", &force, N_("force running gc even if there may be another gc running")),
273 OPT_END()
276 if (argc == 2 && !strcmp(argv[1], "-h"))
277 usage_with_options(builtin_gc_usage, builtin_gc_options);
279 argv_array_pushl(&pack_refs_cmd, "pack-refs", "--all", "--prune", NULL);
280 argv_array_pushl(&reflog, "reflog", "expire", "--all", NULL);
281 argv_array_pushl(&repack, "repack", "-d", "-l", NULL);
282 argv_array_pushl(&prune, "prune", "--expire", NULL );
283 argv_array_pushl(&rerere, "rerere", "gc", NULL);
285 git_config(gc_config, NULL);
287 if (pack_refs < 0)
288 pack_refs = !is_bare_repository();
290 argc = parse_options(argc, argv, prefix, builtin_gc_options,
291 builtin_gc_usage, 0);
292 if (argc > 0)
293 usage_with_options(builtin_gc_usage, builtin_gc_options);
295 if (aggressive) {
296 argv_array_push(&repack, "-f");
297 argv_array_push(&repack, "--depth=250");
298 if (aggressive_window > 0)
299 argv_array_pushf(&repack, "--window=%d", aggressive_window);
301 if (quiet)
302 argv_array_push(&repack, "-q");
304 if (auto_gc) {
306 * Auto-gc should be least intrusive as possible.
308 if (!need_to_gc())
309 return 0;
310 if (!quiet) {
311 if (detach_auto)
312 fprintf(stderr, _("Auto packing the repository in background for optimum performance.\n"));
313 else
314 fprintf(stderr, _("Auto packing the repository for optimum performance.\n"));
315 fprintf(stderr, _("See \"git help gc\" for manual housekeeping.\n"));
317 if (detach_auto)
319 * failure to daemonize is ok, we'll continue
320 * in foreground
322 daemonize();
323 } else
324 add_repack_all_option();
326 name = lock_repo_for_gc(force, &pid);
327 if (name) {
328 if (auto_gc)
329 return 0; /* be quiet on --auto */
330 die(_("gc is already running on machine '%s' pid %"PRIuMAX" (use --force if not)"),
331 name, (uintmax_t)pid);
334 if (pack_refs && run_command_v_opt(pack_refs_cmd.argv, RUN_GIT_CMD))
335 return error(FAILED_RUN, pack_refs_cmd.argv[0]);
337 if (run_command_v_opt(reflog.argv, RUN_GIT_CMD))
338 return error(FAILED_RUN, reflog.argv[0]);
340 if (run_command_v_opt(repack.argv, RUN_GIT_CMD))
341 return error(FAILED_RUN, repack.argv[0]);
343 if (prune_expire) {
344 argv_array_push(&prune, prune_expire);
345 if (quiet)
346 argv_array_push(&prune, "--no-progress");
347 if (run_command_v_opt(prune.argv, RUN_GIT_CMD))
348 return error(FAILED_RUN, prune.argv[0]);
351 if (run_command_v_opt(rerere.argv, RUN_GIT_CMD))
352 return error(FAILED_RUN, rerere.argv[0]);
354 if (auto_gc && too_many_loose_objects())
355 warning(_("There are too many unreachable loose objects; "
356 "run 'git prune' to remove them."));
358 return 0;