1 #include "cache.h"
3 char *prefix_path(const char *prefix, int len, char *path)
4 {
5 char *orig = path;
6 for (;;) {
7 char c;
8 if (*path != '.')
9 break;
10 c = path[1];
11 /* "." */
12 if (!c) {
13 path++;
14 break;
15 }
16 /* "./" */
17 if (c == '/') {
18 path += 2;
19 continue;
20 }
21 if (c != '.')
22 break;
23 c = path[2];
24 if (!c)
25 path += 2;
26 else if (c == '/')
27 path += 3;
28 else
29 break;
30 /* ".." and "../" */
31 /* Remove last component of the prefix */
32 do {
33 if (!len)
34 die("'%s' is outside repository", orig);
35 len--;
36 } while (len && prefix[len-1] != '/');
37 continue;
38 }
39 if (len) {
40 int speclen = strlen(path);
41 char *n = xmalloc(speclen + len + 1);
43 memcpy(n, prefix, len);
44 memcpy(n + len, path, speclen+1);
45 path = n;
46 }
47 return path;
48 }
50 const char **get_pathspec(const char *prefix, char **pathspec)
51 {
52 char *entry = *pathspec;
53 char **p;
54 int prefixlen;
56 if (!prefix && !entry)
57 return NULL;
59 if (!entry) {
60 static const char *spec[2];
61 spec[0] = prefix;
62 spec[1] = NULL;
63 return spec;
64 }
66 /* Otherwise we have to re-write the entries.. */
67 p = pathspec;
68 prefixlen = prefix ? strlen(prefix) : 0;
69 do {
70 *p = prefix_path(prefix, prefixlen, entry);
71 } while ((entry = *++p) != NULL);
72 return (const char **) pathspec;
73 }
75 /*
76 * Test it it looks like we're at the top
77 * level git directory. We want to see a
78 *
79 * - a HEAD symlink and a refs/ directory under ".git"
80 * - either a .git/objects/ directory _or_ the proper
81 * GIT_OBJECT_DIRECTORY environment variable
82 */
83 static int is_toplevel_directory(void)
84 {
85 struct stat st;
87 return !lstat(".git/HEAD", &st) &&
88 S_ISLNK(st.st_mode) &&
89 !access(".git/refs/", X_OK) &&
90 (gitenv(DB_ENVIRONMENT) || !access(".git/objects/", X_OK));
91 }
93 const char *setup_git_directory(void)
94 {
95 static char cwd[PATH_MAX+1];
96 int len, offset;
98 /*
99 * If GIT_DIR is set explicitly, we're not going
100 * to do any discovery
101 */
102 if (gitenv(GIT_DIR_ENVIRONMENT))
103 return NULL;
105 if (!getcwd(cwd, sizeof(cwd)) || cwd[0] != '/')
106 die("Unable to read current working directory");
108 offset = len = strlen(cwd);
109 for (;;) {
110 if (is_toplevel_directory())
111 break;
112 chdir("..");
113 do {
114 if (!offset)
115 die("Not a git repository");
116 } while (cwd[--offset] != '/');
117 }
119 if (offset == len)
120 return NULL;
122 /* Make "offset" point to past the '/', and add a '/' at the end */
123 offset++;
124 cwd[len++] = '/';
125 cwd[len] = 0;
126 return cwd + offset;
127 }