summaryrefslogtreecommitdiff
path: root/setup.c
blob: 36ede3d87483548bb1ce6c19361d7f6584386147 (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
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
#include "cache.h"

const char *prefix_path(const char *prefix, int len, const char *path)
{
	const char *orig = path;
	for (;;) {
		char c;
		if (*path != '.')
			break;
		c = path[1];
		/* "." */
		if (!c) {
			path++;
			break;
		}
		/* "./" */
		if (c == '/') {
			path += 2;
			continue;
		}
		if (c != '.')
			break;
		c = path[2];
		if (!c)
			path += 2;
		else if (c == '/')
			path += 3;
		else
			break;
		/* ".." and "../" */
		/* Remove last component of the prefix */
		do {
			if (!len)
				die("'%s' is outside repository", orig);
			len--;
		} while (len && prefix[len-1] != '/');
		continue;
	}
	if (len) {
		int speclen = strlen(path);
		char *n = xmalloc(speclen + len + 1);
	
		memcpy(n, prefix, len);
		memcpy(n + len, path, speclen+1);
		path = n;
	}
	return path;
}

/* 
 * Unlike prefix_path, this should be used if the named file does
 * not have to interact with index entry; i.e. name of a random file
 * on the filesystem.
 */
const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
{
	static char path[PATH_MAX];
	if (!pfx || !*pfx || arg[0] == '/')
		return arg;
	memcpy(path, pfx, pfx_len);
	strcpy(path + pfx_len, arg);
	return path;
}

const char **get_pathspec(const char *prefix, const char **pathspec)
{
	const char *entry = *pathspec;
	const char **p;
	int prefixlen;

	if (!prefix && !entry)
		return NULL;

	if (!entry) {
		static const char *spec[2];
		spec[0] = prefix;
		spec[1] = NULL;
		return spec;
	}

	/* Otherwise we have to re-write the entries.. */
	p = pathspec;
	prefixlen = prefix ? strlen(prefix) : 0;
	do {
		*p = prefix_path(prefix, prefixlen, entry);
	} while ((entry = *++p) != NULL);
	return (const char **) pathspec;
}

/*
 * Test if it looks like we're at the top level git directory.
 * We want to see:
 *
 *  - either a .git/objects/ directory _or_ the proper
 *    GIT_OBJECT_DIRECTORY environment variable
 *  - a refs/ directory under ".git"
 *  - either a HEAD symlink or a HEAD file that is formatted as
 *    a proper "ref:".
 */
static int is_toplevel_directory(void)
{
	if (access(".git/refs/", X_OK) ||
	    access(getenv(DB_ENVIRONMENT) ?
		   getenv(DB_ENVIRONMENT) : ".git/objects/", X_OK) ||
	    validate_symref(".git/HEAD"))
		return 0;
	return 1;
}

const char *setup_git_directory_gently(int *nongit_ok)
{
	static char cwd[PATH_MAX+1];
	int len, offset;

	/*
	 * If GIT_DIR is set explicitly, we're not going
	 * to do any discovery, but we still do repository
	 * validation.
	 */
	if (getenv(GIT_DIR_ENVIRONMENT)) {
		char path[PATH_MAX];
		int len = strlen(getenv(GIT_DIR_ENVIRONMENT));
		if (sizeof(path) - 40 < len)
			die("'$%s' too big", GIT_DIR_ENVIRONMENT);
		memcpy(path, getenv(GIT_DIR_ENVIRONMENT), len);
		
		strcpy(path + len, "/refs");
		if (access(path, X_OK))
			goto bad_dir_environ;
		strcpy(path + len, "/HEAD");
		if (validate_symref(path))
			goto bad_dir_environ;
		if (getenv(DB_ENVIRONMENT)) {
			if (access(getenv(DB_ENVIRONMENT), X_OK))
				goto bad_dir_environ;
		}
		else {
			strcpy(path + len, "/objects");
			if (access(path, X_OK))
				goto bad_dir_environ;
		}
		return NULL;
	bad_dir_environ:
		path[len] = 0;
		die("Not a git repository: '%s'", path);
	}

	if (!getcwd(cwd, sizeof(cwd)) || cwd[0] != '/')
		die("Unable to read current working directory");

	offset = len = strlen(cwd);
	for (;;) {
		if (is_toplevel_directory())
			break;
		chdir("..");
		do {
			if (!offset) {
				if (nongit_ok) {
					if (chdir(cwd))
						die("Cannot come back to cwd");
					*nongit_ok = 1;
					return NULL;
				}
				die("Not a git repository");
			}
		} while (cwd[--offset] != '/');
	}

	if (offset == len)
		return NULL;

	/* Make "offset" point to past the '/', and add a '/' at the end */
	offset++;
	cwd[len++] = '/';
	cwd[len] = 0;
	return cwd + offset;
}

int check_repository_format_version(const char *var, const char *value)
{
       if (strcmp(var, "core.repositoryformatversion") == 0)
               repository_format_version = git_config_int(var, value);
	else if (strcmp(var, "core.sharedrepository") == 0)
		shared_repository = git_config_bool(var, value);
       return 0;
}

int check_repository_format(void)
{
	git_config(check_repository_format_version);
	if (GIT_REPO_VERSION < repository_format_version)
		die ("Expected git repo version <= %d, found %d",
		     GIT_REPO_VERSION, repository_format_version);
	return 0;
}

const char *setup_git_directory(void)
{
	const char *retval = setup_git_directory_gently(NULL);
	check_repository_format();
	return retval;
}