Merge branch 'lt/case-insensitive'
[git/git.git] / builtin-gc.c
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
13 #include "builtin.h"
14 #include "cache.h"
15 #include "parse-options.h"
16 #include "run-command.h"
17
18 #define FAILED_RUN "failed to run %s"
19
20 static const char * const builtin_gc_usage[] = {
21 "git-gc [options]",
22 NULL
23 };
24
25 static int pack_refs = 1;
26 static int aggressive_window = -1;
27 static int gc_auto_threshold = 6700;
28 static int gc_auto_pack_limit = 50;
29 static char *prune_expire = "2.weeks.ago";
30
31 #define MAX_ADD 10
32 static const char *argv_pack_refs[] = {"pack-refs", "--all", "--prune", NULL};
33 static const char *argv_reflog[] = {"reflog", "expire", "--all", NULL};
34 static const char *argv_repack[MAX_ADD] = {"repack", "-d", "-l", NULL};
35 static const char *argv_prune[] = {"prune", "--expire", NULL, NULL};
36 static const char *argv_rerere[] = {"rerere", "gc", NULL};
37
38 static int gc_config(const char *var, const char *value)
39 {
40 if (!strcmp(var, "gc.packrefs")) {
41 if (value && !strcmp(value, "notbare"))
42 pack_refs = -1;
43 else
44 pack_refs = git_config_bool(var, value);
45 return 0;
46 }
47 if (!strcmp(var, "gc.aggressivewindow")) {
48 aggressive_window = git_config_int(var, value);
49 return 0;
50 }
51 if (!strcmp(var, "gc.auto")) {
52 gc_auto_threshold = git_config_int(var, value);
53 return 0;
54 }
55 if (!strcmp(var, "gc.autopacklimit")) {
56 gc_auto_pack_limit = git_config_int(var, value);
57 return 0;
58 }
59 if (!strcmp(var, "gc.pruneexpire")) {
60 if (!value)
61 return config_error_nonbool(var);
62 if (strcmp(value, "now")) {
63 unsigned long now = approxidate("now");
64 if (approxidate(value) >= now)
65 return error("Invalid %s: '%s'", var, value);
66 }
67 prune_expire = xstrdup(value);
68 return 0;
69 }
70 return git_default_config(var, value);
71 }
72
73 static void append_option(const char **cmd, const char *opt, int max_length)
74 {
75 int i;
76
77 for (i = 0; cmd[i]; i++)
78 ;
79
80 if (i + 2 >= max_length)
81 die("Too many options specified");
82 cmd[i++] = opt;
83 cmd[i] = NULL;
84 }
85
86 static int too_many_loose_objects(void)
87 {
88 /*
89 * Quickly check if a "gc" is needed, by estimating how
90 * many loose objects there are. Because SHA-1 is evenly
91 * distributed, we can check only one and get a reasonable
92 * estimate.
93 */
94 char path[PATH_MAX];
95 const char *objdir = get_object_directory();
96 DIR *dir;
97 struct dirent *ent;
98 int auto_threshold;
99 int num_loose = 0;
100 int needed = 0;
101
102 if (gc_auto_threshold <= 0)
103 return 0;
104
105 if (sizeof(path) <= snprintf(path, sizeof(path), "%s/17", objdir)) {
106 warning("insanely long object directory %.*s", 50, objdir);
107 return 0;
108 }
109 dir = opendir(path);
110 if (!dir)
111 return 0;
112
113 auto_threshold = (gc_auto_threshold + 255) / 256;
114 while ((ent = readdir(dir)) != NULL) {
115 if (strspn(ent->d_name, "0123456789abcdef") != 38 ||
116 ent->d_name[38] != '\0')
117 continue;
118 if (++num_loose > auto_threshold) {
119 needed = 1;
120 break;
121 }
122 }
123 closedir(dir);
124 return needed;
125 }
126
127 static int too_many_packs(void)
128 {
129 struct packed_git *p;
130 int cnt;
131
132 if (gc_auto_pack_limit <= 0)
133 return 0;
134
135 prepare_packed_git();
136 for (cnt = 0, p = packed_git; p; p = p->next) {
137 char path[PATH_MAX];
138 size_t len;
139 int keep;
140
141 if (!p->pack_local)
142 continue;
143 len = strlen(p->pack_name);
144 if (PATH_MAX <= len + 1)
145 continue; /* oops, give up */
146 memcpy(path, p->pack_name, len-5);
147 memcpy(path + len - 5, ".keep", 6);
148 keep = access(p->pack_name, F_OK) && (errno == ENOENT);
149 if (keep)
150 continue;
151 /*
152 * Perhaps check the size of the pack and count only
153 * very small ones here?
154 */
155 cnt++;
156 }
157 return gc_auto_pack_limit <= cnt;
158 }
159
160 static int run_hook(void)
161 {
162 const char *argv[2];
163 struct child_process hook;
164 int ret;
165
166 argv[0] = git_path("hooks/pre-auto-gc");
167 argv[1] = NULL;
168
169 if (access(argv[0], X_OK) < 0)
170 return 0;
171
172 memset(&hook, 0, sizeof(hook));
173 hook.argv = argv;
174 hook.no_stdin = 1;
175 hook.stdout_to_stderr = 1;
176
177 ret = start_command(&hook);
178 if (ret) {
179 warning("Could not spawn %s", argv[0]);
180 return ret;
181 }
182 ret = finish_command(&hook);
183 if (ret == -ERR_RUN_COMMAND_WAITPID_SIGNAL)
184 warning("%s exited due to uncaught signal", argv[0]);
185 return ret;
186 }
187
188 static int need_to_gc(void)
189 {
190 /*
191 * Setting gc.auto to 0 or negative can disable the
192 * automatic gc.
193 */
194 if (gc_auto_threshold <= 0)
195 return 0;
196
197 /*
198 * If there are too many loose objects, but not too many
199 * packs, we run "repack -d -l". If there are too many packs,
200 * we run "repack -A -d -l". Otherwise we tell the caller
201 * there is no need.
202 */
203 if (too_many_packs())
204 append_option(argv_repack, "-A", MAX_ADD);
205 else if (!too_many_loose_objects())
206 return 0;
207
208 if (run_hook())
209 return 0;
210 return 1;
211 }
212
213 int cmd_gc(int argc, const char **argv, const char *prefix)
214 {
215 int prune = 0;
216 int aggressive = 0;
217 int auto_gc = 0;
218 int quiet = 0;
219 char buf[80];
220
221 struct option builtin_gc_options[] = {
222 OPT_BOOLEAN(0, "prune", &prune, "prune unreferenced objects"),
223 OPT_BOOLEAN(0, "aggressive", &aggressive, "be more thorough (increased runtime)"),
224 OPT_BOOLEAN(0, "auto", &auto_gc, "enable auto-gc mode"),
225 OPT_BOOLEAN('q', "quiet", &quiet, "suppress progress reports"),
226 OPT_END()
227 };
228
229 git_config(gc_config);
230
231 if (pack_refs < 0)
232 pack_refs = !is_bare_repository();
233
234 argc = parse_options(argc, argv, builtin_gc_options, builtin_gc_usage, 0);
235 if (argc > 0)
236 usage_with_options(builtin_gc_usage, builtin_gc_options);
237
238 if (aggressive) {
239 append_option(argv_repack, "-f", MAX_ADD);
240 if (aggressive_window > 0) {
241 sprintf(buf, "--window=%d", aggressive_window);
242 append_option(argv_repack, buf, MAX_ADD);
243 }
244 }
245 if (quiet)
246 append_option(argv_repack, "-q", MAX_ADD);
247
248 if (auto_gc) {
249 /*
250 * Auto-gc should be least intrusive as possible.
251 */
252 prune = 0;
253 if (!need_to_gc())
254 return 0;
255 fprintf(stderr, "Auto packing your repository for optimum "
256 "performance. You may also\n"
257 "run \"git gc\" manually. See "
258 "\"git help gc\" for more information.\n");
259 } else {
260 /*
261 * Use safer (for shared repos) "-A" option to
262 * repack when not pruning. Auto-gc makes its
263 * own decision.
264 */
265 if (prune)
266 append_option(argv_repack, "-a", MAX_ADD);
267 else
268 append_option(argv_repack, "-A", MAX_ADD);
269 }
270
271 if (pack_refs && run_command_v_opt(argv_pack_refs, RUN_GIT_CMD))
272 return error(FAILED_RUN, argv_pack_refs[0]);
273
274 if (run_command_v_opt(argv_reflog, RUN_GIT_CMD))
275 return error(FAILED_RUN, argv_reflog[0]);
276
277 if (run_command_v_opt(argv_repack, RUN_GIT_CMD))
278 return error(FAILED_RUN, argv_repack[0]);
279
280 argv_prune[2] = prune_expire;
281 if (run_command_v_opt(argv_prune, RUN_GIT_CMD))
282 return error(FAILED_RUN, argv_prune[0]);
283
284 if (run_command_v_opt(argv_rerere, RUN_GIT_CMD))
285 return error(FAILED_RUN, argv_rerere[0]);
286
287 if (auto_gc && too_many_loose_objects())
288 warning("There are too many unreachable loose objects; "
289 "run 'git prune' to remove them.");
290
291 return 0;
292 }