print unlink(2) errno in copy_or_link_directory
[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 = 250;
27 static int gc_auto_threshold = 6700;
28 static int gc_auto_pack_limit = 50;
29 static const 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, void *cb)
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 && strcmp(value, "now")) {
61                         unsigned long now = approxidate("now");
62                         if (approxidate(value) >= now)
63                                 return error("Invalid %s: '%s'", var, value);
64                 }
65                 return git_config_string(&prune_expire, var, value);
66         }
67         return git_default_config(var, value, cb);
68 }
69
70 static void append_option(const char **cmd, const char *opt, int max_length)
71 {
72         int i;
73
74         for (i = 0; cmd[i]; i++)
75                 ;
76
77         if (i + 2 >= max_length)
78                 die("Too many options specified");
79         cmd[i++] = opt;
80         cmd[i] = NULL;
81 }
82
83 static int too_many_loose_objects(void)
84 {
85         /*
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.
90          */
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;
98
99         if (gc_auto_threshold <= 0)
100                 return 0;
101
102         if (sizeof(path) <= snprintf(path, sizeof(path), "%s/17", objdir)) {
103                 warning("insanely long object directory %.*s", 50, objdir);
104                 return 0;
105         }
106         dir = opendir(path);
107         if (!dir)
108                 return 0;
109
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;
118                 }
119         }
120         closedir(dir);
121         return needed;
122 }
123
124 static int too_many_packs(void)
125 {
126         struct packed_git *p;
127         int cnt;
128
129         if (gc_auto_pack_limit <= 0)
130                 return 0;
131
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;
138                 /*
139                  * Perhaps check the size of the pack and count only
140                  * very small ones here?
141                  */
142                 cnt++;
143         }
144         return gc_auto_pack_limit <= cnt;
145 }
146
147 static int need_to_gc(void)
148 {
149         /*
150          * Setting gc.auto to 0 or negative can disable the
151          * automatic gc.
152          */
153         if (gc_auto_threshold <= 0)
154                 return 0;
155
156         /*
157          * If there are too many loose objects, but not too many
158          * packs, we run "repack -d -l".  If there are too many packs,
159          * we run "repack -A -d -l".  Otherwise we tell the caller
160          * there is no need.
161          */
162         if (too_many_packs())
163                 append_option(argv_repack,
164                               prune_expire && !strcmp(prune_expire, "now") ?
165                               "-a" : "-A",
166                               MAX_ADD);
167         else if (!too_many_loose_objects())
168                 return 0;
169
170         if (run_hook(NULL, "pre-auto-gc", NULL))
171                 return 0;
172         return 1;
173 }
174
175 int cmd_gc(int argc, const char **argv, const char *prefix)
176 {
177         int aggressive = 0;
178         int auto_gc = 0;
179         int quiet = 0;
180         char buf[80];
181
182         struct option builtin_gc_options[] = {
183                 { OPTION_STRING, 0, "prune", &prune_expire, "date",
184                         "prune unreferenced objects",
185                         PARSE_OPT_OPTARG, NULL, (intptr_t)prune_expire },
186                 OPT_BOOLEAN(0, "aggressive", &aggressive, "be more thorough (increased runtime)"),
187                 OPT_BOOLEAN(0, "auto", &auto_gc, "enable auto-gc mode"),
188                 OPT_BOOLEAN('q', "quiet", &quiet, "suppress progress reports"),
189                 OPT_END()
190         };
191
192         git_config(gc_config, NULL);
193
194         if (pack_refs < 0)
195                 pack_refs = !is_bare_repository();
196
197         argc = parse_options(argc, argv, builtin_gc_options, builtin_gc_usage, 0);
198         if (argc > 0)
199                 usage_with_options(builtin_gc_usage, builtin_gc_options);
200
201         if (aggressive) {
202                 append_option(argv_repack, "-f", MAX_ADD);
203                 append_option(argv_repack, "--depth=250", MAX_ADD);
204                 if (aggressive_window > 0) {
205                         sprintf(buf, "--window=%d", aggressive_window);
206                         append_option(argv_repack, buf, MAX_ADD);
207                 }
208         }
209         if (quiet)
210                 append_option(argv_repack, "-q", MAX_ADD);
211
212         if (auto_gc) {
213                 /*
214                  * Auto-gc should be least intrusive as possible.
215                  */
216                 if (!need_to_gc())
217                         return 0;
218                 fprintf(stderr, "Auto packing your repository for optimum "
219                         "performance. You may also\n"
220                         "run \"git gc\" manually. See "
221                         "\"git help gc\" for more information.\n");
222         } else
223                 append_option(argv_repack,
224                               prune_expire && !strcmp(prune_expire, "now")
225                               ? "-a" : "-A",
226                               MAX_ADD);
227
228         if (pack_refs && run_command_v_opt(argv_pack_refs, RUN_GIT_CMD))
229                 return error(FAILED_RUN, argv_pack_refs[0]);
230
231         if (run_command_v_opt(argv_reflog, RUN_GIT_CMD))
232                 return error(FAILED_RUN, argv_reflog[0]);
233
234         if (run_command_v_opt(argv_repack, RUN_GIT_CMD))
235                 return error(FAILED_RUN, argv_repack[0]);
236
237         if (prune_expire) {
238                 argv_prune[2] = prune_expire;
239                 if (run_command_v_opt(argv_prune, RUN_GIT_CMD))
240                         return error(FAILED_RUN, argv_prune[0]);
241         }
242
243         if (run_command_v_opt(argv_rerere, RUN_GIT_CMD))
244                 return error(FAILED_RUN, argv_rerere[0]);
245
246         if (auto_gc && too_many_loose_objects())
247                 warning("There are too many unreachable loose objects; "
248                         "run 'git prune' to remove them.");
249
250         return 0;
251 }