aboutsummaryrefslogtreecommitdiff
path: root/builtin-gc.c
blob: bf29f5e1a2b07d66371139948531eb5833fcbbdf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/*
 * git gc builtin command
 *
 * Cleanup unreachable files and optimize the repository.
 *
 * Copyright (c) 2007 James Bowes
 *
 * Based on git-gc.sh, which is
 *
 * Copyright (c) 2006 Shawn O. Pearce
 */

#include "builtin.h"
#include "cache.h"
#include "run-command.h"

#define FAILED_RUN "failed to run %s"

static const char builtin_gc_usage[] = "git-gc [--prune] [--aggressive]";

static int pack_refs = 1;
static int aggressive_window = -1;
static int gc_auto_threshold = 6700;

#define MAX_ADD 10
static const char *argv_pack_refs[] = {"pack-refs", "--all", "--prune", NULL};
static const char *argv_reflog[] = {"reflog", "expire", "--all", NULL};
static const char *argv_repack[MAX_ADD] = {"repack", "-a", "-d", "-l", NULL};
static const char *argv_prune[] = {"prune", NULL};
static const char *argv_rerere[] = {"rerere", "gc", NULL};

static const char *argv_repack_auto[] = {"repack", "-d", "-l", NULL};

static int gc_config(const char *var, const char *value)
{
	if (!strcmp(var, "gc.packrefs")) {
		if (!strcmp(value, "notbare"))
			pack_refs = -1;
		else
			pack_refs = git_config_bool(var, value);
		return 0;
	}
	if (!strcmp(var, "gc.aggressivewindow")) {
		aggressive_window = git_config_int(var, value);
		return 0;
	}
	if (!strcmp(var, "gc.auto")) {
		gc_auto_threshold = git_config_int(var, value);
		return 0;
	}
	return git_default_config(var, value);
}

static void append_option(const char **cmd, const char *opt, int max_length)
{
	int i;

	for (i = 0; cmd[i]; i++)
		;

	if (i + 2 >= max_length)
		die("Too many options specified");
	cmd[i++] = opt;
	cmd[i] = NULL;
}

static int too_many_loose_objects(void)
{
	/*
	 * Quickly check if a "gc" is needed, by estimating how
	 * many loose objects there are.  Because SHA-1 is evenly
	 * distributed, we can check only one and get a reasonable
	 * estimate.
	 */
	char path[PATH_MAX];
	const char *objdir = get_object_directory();
	DIR *dir;
	struct dirent *ent;
	int auto_threshold;
	int num_loose = 0;
	int needed = 0;

	if (sizeof(path) <= snprintf(path, sizeof(path), "%s/17", objdir)) {
		warning("insanely long object directory %.*s", 50, objdir);
		return 0;
	}
	dir = opendir(path);
	if (!dir)
		return 0;

	auto_threshold = (gc_auto_threshold + 255) / 256;
	while ((ent = readdir(dir)) != NULL) {
		if (strspn(ent->d_name, "0123456789abcdef") != 38 ||
		    ent->d_name[38] != '\0')
			continue;
		if (++num_loose > auto_threshold) {
			needed = 1;
			break;
		}
	}
	closedir(dir);
	return needed;
}

static int need_to_gc(void)
{
	/*
	 * Setting gc.auto to 0 or negative can disable the
	 * automatic gc
	 */
	if (gc_auto_threshold <= 0)
		return 0;

	return too_many_loose_objects();
}

int cmd_gc(int argc, const char **argv, const char *prefix)
{
	int i;
	int prune = 0;
	int auto_gc = 0;
	char buf[80];

	git_config(gc_config);

	if (pack_refs < 0)
		pack_refs = !is_bare_repository();

	for (i = 1; i < argc; i++) {
		const char *arg = argv[i];
		if (!strcmp(arg, "--prune")) {
			prune = 1;
			continue;
		}
		if (!strcmp(arg, "--aggressive")) {
			append_option(argv_repack, "-f", MAX_ADD);
			if (aggressive_window > 0) {
				sprintf(buf, "--window=%d", aggressive_window);
				append_option(argv_repack, buf, MAX_ADD);
			}
			continue;
		}
		if (!strcmp(arg, "--auto")) {
			auto_gc = 1;
			continue;
		}
		break;
	}
	if (i != argc)
		usage(builtin_gc_usage);

	if (auto_gc) {
		/*
		 * Auto-gc should be least intrusive as possible.
		 */
		prune = 0;
		for (i = 0; i < ARRAY_SIZE(argv_repack_auto); i++)
			argv_repack[i] = argv_repack_auto[i];
		if (!need_to_gc())
			return 0;
	}

	if (pack_refs && run_command_v_opt(argv_pack_refs, RUN_GIT_CMD))
		return error(FAILED_RUN, argv_pack_refs[0]);

	if (run_command_v_opt(argv_reflog, RUN_GIT_CMD))
		return error(FAILED_RUN, argv_reflog[0]);

	if (run_command_v_opt(argv_repack, RUN_GIT_CMD))
		return error(FAILED_RUN, argv_repack[0]);

	if (prune && run_command_v_opt(argv_prune, RUN_GIT_CMD))
		return error(FAILED_RUN, argv_prune[0]);

	if (run_command_v_opt(argv_rerere, RUN_GIT_CMD))
		return error(FAILED_RUN, argv_rerere[0]);

	if (auto_gc && too_many_loose_objects())
		warning("There are too many unreachable loose objects; "
			"run 'git prune' to remove them.");

	return 0;
}