git-commit-vandalism/setup.c
Linus Torvalds 5f5608bcec [PATCH] Make .git directory validation code test HEAD
Inspired by a report by Kalle Valo, this changes git-sh-setup-script and
the "setup_git_directory()" function to test that $GIT_DIR/HEAD is a
symlink, since a number of core git features depend on that these days.

We used to allow a regular file there, but git-fsck-cache has been
complaining about that for a while, and anything that uses branches
depends on the HEAD file being a symlink, so let's just encode that as a
fundamental requirement.

Before, a non-symlink HEAD file would appear to work, but have subtle bugs
like not having the HEAD show up as a valid reference (because it wasn't
under "refs"). Now, we will complain loudly, and the user can fix it up
trivially instead of getting strange behaviour.

This also removes the tests for "$GIT_DIR" and "$GIT_OBJECT_DIRECTORY"
being directories, since the other tests will implicitly test for that
anyway (ie the tests for HEAD, refs and 00 would fail).

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2005-08-27 23:20:24 -07:00

128 lines
2.4 KiB
C

#include "cache.h"
char *prefix_path(const char *prefix, int len, char *path)
{
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;
}
const char **get_pathspec(const char *prefix, char **pathspec)
{
char *entry = *pathspec;
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 it it looks like we're at the top
* level git directory. We want to see a
*
* - a HEAD symlink and a refs/ directory under ".git"
* - either a .git/objects/ directory _or_ the proper
* GIT_OBJECT_DIRECTORY environment variable
*/
static int is_toplevel_directory(void)
{
struct stat st;
return !lstat(".git/HEAD", &st) &&
S_ISLNK(st.st_mode) &&
!access(".git/refs/", X_OK) &&
(gitenv(DB_ENVIRONMENT) || !access(".git/objects/", X_OK));
}
const char *setup_git_directory(void)
{
static char cwd[PATH_MAX+1];
int len, offset;
/*
* If GIT_DIR is set explicitly, we're not going
* to do any discovery
*/
if (gitenv(GIT_DIR_ENVIRONMENT))
return NULL;
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)
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;
}