Merge branch 'maint-1.6.0' into maint-1.6.1
[git/spearce.git] / builtin-gc.c
blobf8eae4adb41d9c338c07aa161e7305bb16742a1e
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"
18 #define FAILED_RUN "failed to run %s"
20 static const char * const builtin_gc_usage[] = {
21 "git gc [options]",
22 NULL
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 const char *prune_expire = "2.weeks.ago";
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};
38 static int gc_config(const char *var, const char *value, void *cb)
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;
47 if (!strcmp(var, "gc.aggressivewindow")) {
48 aggressive_window = git_config_int(var, value);
49 return 0;
51 if (!strcmp(var, "gc.auto")) {
52 gc_auto_threshold = git_config_int(var, value);
53 return 0;
55 if (!strcmp(var, "gc.autopacklimit")) {
56 gc_auto_pack_limit = git_config_int(var, value);
57 return 0;
59 if (!strcmp(var, "gc.pruneexpire")) {
60 if (value && strcmp(value, "now")) {
61 unsigned long now = approxidate("now");
62 if (approxidate(value) >= now)
63 return error("Invalid %s: '%s'", var, value);
65 return git_config_string(&prune_expire, var, value);
67 return git_default_config(var, value, cb);
70 static void append_option(const char **cmd, const char *opt, int max_length)
72 int i;
74 for (i = 0; cmd[i]; i++)
77 if (i + 2 >= max_length)
78 die("Too many options specified");
79 cmd[i++] = opt;
80 cmd[i] = NULL;
83 static int too_many_loose_objects(void)
86 * Quickly check if a "gc" is needed, by estimating how
87 * many loose objects there are. Because SHA-1 is evenly
88 * distributed, we can check only one and get a reasonable
89 * estimate.
91 char path[PATH_MAX];
92 const char *objdir = get_object_directory();
93 DIR *dir;
94 struct dirent *ent;
95 int auto_threshold;
96 int num_loose = 0;
97 int needed = 0;
99 if (gc_auto_threshold <= 0)
100 return 0;
102 if (sizeof(path) <= snprintf(path, sizeof(path), "%s/17", objdir)) {
103 warning("insanely long object directory %.*s", 50, objdir);
104 return 0;
106 dir = opendir(path);
107 if (!dir)
108 return 0;
110 auto_threshold = (gc_auto_threshold + 255) / 256;
111 while ((ent = readdir(dir)) != NULL) {
112 if (strspn(ent->d_name, "0123456789abcdef") != 38 ||
113 ent->d_name[38] != '\0')
114 continue;
115 if (++num_loose > auto_threshold) {
116 needed = 1;
117 break;
120 closedir(dir);
121 return needed;
124 static int too_many_packs(void)
126 struct packed_git *p;
127 int cnt;
129 if (gc_auto_pack_limit <= 0)
130 return 0;
132 prepare_packed_git();
133 for (cnt = 0, p = packed_git; p; p = p->next) {
134 if (!p->pack_local)
135 continue;
136 if (p->pack_keep)
137 continue;
139 * Perhaps check the size of the pack and count only
140 * very small ones here?
142 cnt++;
144 return gc_auto_pack_limit <= cnt;
147 static int run_hook(void)
149 const char *argv[2];
150 struct child_process hook;
151 int ret;
153 argv[0] = git_path("hooks/pre-auto-gc");
154 argv[1] = NULL;
156 if (access(argv[0], X_OK) < 0)
157 return 0;
159 memset(&hook, 0, sizeof(hook));
160 hook.argv = argv;
161 hook.no_stdin = 1;
162 hook.stdout_to_stderr = 1;
164 ret = start_command(&hook);
165 if (ret) {
166 warning("Could not spawn %s", argv[0]);
167 return ret;
169 ret = finish_command(&hook);
170 if (ret == -ERR_RUN_COMMAND_WAITPID_SIGNAL)
171 warning("%s exited due to uncaught signal", argv[0]);
172 return ret;
175 static int need_to_gc(void)
178 * Setting gc.auto to 0 or negative can disable the
179 * automatic gc.
181 if (gc_auto_threshold <= 0)
182 return 0;
185 * If there are too many loose objects, but not too many
186 * packs, we run "repack -d -l". If there are too many packs,
187 * we run "repack -A -d -l". Otherwise we tell the caller
188 * there is no need.
190 if (too_many_packs())
191 append_option(argv_repack,
192 !strcmp(prune_expire, "now") ? "-a" : "-A",
193 MAX_ADD);
194 else if (!too_many_loose_objects())
195 return 0;
197 if (run_hook())
198 return 0;
199 return 1;
202 int cmd_gc(int argc, const char **argv, const char *prefix)
204 int prune = 0;
205 int aggressive = 0;
206 int auto_gc = 0;
207 int quiet = 0;
208 char buf[80];
210 struct option builtin_gc_options[] = {
211 OPT_BOOLEAN(0, "prune", &prune, "prune unreferenced objects (deprecated)"),
212 OPT_BOOLEAN(0, "aggressive", &aggressive, "be more thorough (increased runtime)"),
213 OPT_BOOLEAN(0, "auto", &auto_gc, "enable auto-gc mode"),
214 OPT_BOOLEAN('q', "quiet", &quiet, "suppress progress reports"),
215 OPT_END()
218 git_config(gc_config, NULL);
220 if (pack_refs < 0)
221 pack_refs = !is_bare_repository();
223 argc = parse_options(argc, argv, builtin_gc_options, builtin_gc_usage, 0);
224 if (argc > 0)
225 usage_with_options(builtin_gc_usage, builtin_gc_options);
227 if (aggressive) {
228 append_option(argv_repack, "-f", MAX_ADD);
229 if (aggressive_window > 0) {
230 sprintf(buf, "--window=%d", aggressive_window);
231 append_option(argv_repack, buf, MAX_ADD);
234 if (quiet)
235 append_option(argv_repack, "-q", MAX_ADD);
237 if (auto_gc) {
239 * Auto-gc should be least intrusive as possible.
241 if (!need_to_gc())
242 return 0;
243 fprintf(stderr, "Auto packing your repository for optimum "
244 "performance. You may also\n"
245 "run \"git gc\" manually. See "
246 "\"git help gc\" for more information.\n");
247 } else
248 append_option(argv_repack,
249 !strcmp(prune_expire, "now") ? "-a" : "-A",
250 MAX_ADD);
252 if (pack_refs && run_command_v_opt(argv_pack_refs, RUN_GIT_CMD))
253 return error(FAILED_RUN, argv_pack_refs[0]);
255 if (run_command_v_opt(argv_reflog, RUN_GIT_CMD))
256 return error(FAILED_RUN, argv_reflog[0]);
258 if (run_command_v_opt(argv_repack, RUN_GIT_CMD))
259 return error(FAILED_RUN, argv_repack[0]);
261 argv_prune[2] = prune_expire;
262 if (run_command_v_opt(argv_prune, RUN_GIT_CMD))
263 return error(FAILED_RUN, argv_prune[0]);
265 if (run_command_v_opt(argv_rerere, RUN_GIT_CMD))
266 return error(FAILED_RUN, argv_rerere[0]);
268 if (auto_gc && too_many_loose_objects())
269 warning("There are too many unreachable loose objects; "
270 "run 'git prune' to remove them.");
272 return 0;