@ -91,54 +91,271 @@ static void replace_dir(struct strbuf *buf, int len, const char *newdir)
@@ -91,54 +91,271 @@ static void replace_dir(struct strbuf *buf, int len, const char *newdir)
buf->buf[newlen] = '/';
}
static const char *common_list[] = {
"/branches", "/hooks", "/info", "!/logs", "/lost-found",
"/objects", "/refs", "/remotes", "/worktrees", "/rr-cache", "/svn",
"config", "!gc.pid", "packed-refs", "shallow",
NULL
struct common_dir {
/* Not considered garbage for report_linked_checkout_garbage */
unsigned ignore_garbage:1;
unsigned is_dir:1;
/* Not common even though its parent is */
unsigned exclude:1;
const char *dirname;
};
static void update_common_dir(struct strbuf *buf, int git_dir_len)
static struct common_dir common_list[] = {
{ 0, 1, 0, "branches" },
{ 0, 1, 0, "hooks" },
{ 0, 1, 0, "info" },
{ 0, 0, 1, "info/sparse-checkout" },
{ 1, 1, 0, "logs" },
{ 1, 1, 1, "logs/HEAD" },
{ 0, 1, 1, "logs/refs/bisect" },
{ 0, 1, 0, "lost-found" },
{ 0, 1, 0, "objects" },
{ 0, 1, 0, "refs" },
{ 0, 1, 1, "refs/bisect" },
{ 0, 1, 0, "remotes" },
{ 0, 1, 0, "worktrees" },
{ 0, 1, 0, "rr-cache" },
{ 0, 1, 0, "svn" },
{ 0, 0, 0, "config" },
{ 1, 0, 0, "gc.pid" },
{ 0, 0, 0, "packed-refs" },
{ 0, 0, 0, "shallow" },
{ 0, 0, 0, NULL }
};
/*
* A compressed trie. A trie node consists of zero or more characters that
* are common to all elements with this prefix, optionally followed by some
* children. If value is not NULL, the trie node is a terminal node.
*
* For example, consider the following set of strings:
* abc
* def
* definite
* definition
*
* The trie would look look like:
* root: len = 0, children a and d non-NULL, value = NULL.
* a: len = 2, contents = bc, value = (data for "abc")
* d: len = 2, contents = ef, children i non-NULL, value = (data for "def")
* i: len = 3, contents = nit, children e and i non-NULL, value = NULL
* e: len = 0, children all NULL, value = (data for "definite")
* i: len = 2, contents = on, children all NULL,
* value = (data for "definition")
*/
struct trie {
struct trie *children[256];
int len;
char *contents;
void *value;
};
static struct trie *make_trie_node(const char *key, void *value)
{
char *base = buf->buf + git_dir_len;
const char **p;
if (is_dir_file(base, "logs", "HEAD") ||
is_dir_file(base, "info", "sparse-checkout"))
return; /* keep this in $GIT_DIR */
for (p = common_list; *p; p++) {
const char *path = *p;
int is_dir = 0;
if (*path == '!')
path++;
if (*path == '/') {
path++;
is_dir = 1;
struct trie *new_node = xcalloc(1, sizeof(*new_node));
new_node->len = strlen(key);
if (new_node->len) {
new_node->contents = xmalloc(new_node->len);
memcpy(new_node->contents, key, new_node->len);
}
new_node->value = value;
return new_node;
}
/*
* Add a key/value pair to a trie. The key is assumed to be \0-terminated.
* If there was an existing value for this key, return it.
*/
static void *add_to_trie(struct trie *root, const char *key, void *value)
{
struct trie *child;
void *old;
int i;
if (!*key) {
/* we have reached the end of the key */
old = root->value;
root->value = value;
return old;
}
for (i = 0; i < root->len; i++) {
if (root->contents[i] == key[i])
continue;
/*
* Split this node: child will contain this node's
* existing children.
*/
child = malloc(sizeof(*child));
memcpy(child->children, root->children, sizeof(root->children));
child->len = root->len - i - 1;
if (child->len) {
child->contents = xstrndup(root->contents + i + 1,
child->len);
}
if (is_dir && dir_prefix(base, path)) {
replace_dir(buf, git_dir_len, get_git_common_dir());
return;
child->value = root->value;
root->value = NULL;
root->len = i;
memset(root->children, 0, sizeof(root->children));
root->children[(unsigned char)root->contents[i]] = child;
/* This is the newly-added child. */
root->children[(unsigned char)key[i]] =
make_trie_node(key + i + 1, value);
return NULL;
}
/* We have matched the entire compressed section */
if (key[i]) {
child = root->children[(unsigned char)key[root->len]];
if (child) {
return add_to_trie(child, key + root->len + 1, value);
} else {
child = make_trie_node(key + root->len + 1, value);
root->children[(unsigned char)key[root->len]] = child;
return NULL;
}
if (!is_dir && !strcmp(base, path)) {
replace_dir(buf, git_dir_len, get_git_common_dir());
return;
}
old = root->value;
root->value = value;
return old;
}
typedef int (*match_fn)(const char *unmatched, void *data, void *baton);
/*
* Search a trie for some key. Find the longest /-or-\0-terminated
* prefix of the key for which the trie contains a value. Call fn
* with the unmatched portion of the key and the found value, and
* return its return value. If there is no such prefix, return -1.
*
* The key is partially normalized: consecutive slashes are skipped.
*
* For example, consider the trie containing only [refs,
* refs/worktree] (both with values).
*
* | key | unmatched | val from node | return value |
* |-----------------|------------|---------------|--------------|
* | a | not called | n/a | -1 |
* | refs | \0 | refs | as per fn |
* | refs/ | / | refs | as per fn |
* | refs/w | /w | refs | as per fn |
* | refs/worktree | \0 | refs/worktree | as per fn |
* | refs/worktree/ | / | refs/worktree | as per fn |
* | refs/worktree/a | /a | refs/worktree | as per fn |
* |-----------------|------------|---------------|--------------|
*
*/
static int trie_find(struct trie *root, const char *key, match_fn fn,
void *baton)
{
int i;
int result;
struct trie *child;
if (!*key) {
/* we have reached the end of the key */
if (root->value && !root->len)
return fn(key, root->value, baton);
else
return -1;
}
for (i = 0; i < root->len; i++) {
/* Partial path normalization: skip consecutive slashes. */
if (key[i] == '/' && key[i+1] == '/') {
key++;
continue;
}
if (root->contents[i] != key[i])
return -1;
}
/* Matched the entire compressed section */
key += i;
if (!*key)
/* End of key */
return fn(key, root->value, baton);
/* Partial path normalization: skip consecutive slashes */
while (key[0] == '/' && key[1] == '/')
key++;
child = root->children[(unsigned char)*key];
if (child)
result = trie_find(child, key + 1, fn, baton);
else
result = -1;
if (result >= 0 || (*key != '/' && *key != 0))
return result;
if (root->value)
return fn(key, root->value, baton);
else
return -1;
}
static struct trie common_trie;
static int common_trie_done_setup;
static void init_common_trie(void)
{
struct common_dir *p;
if (common_trie_done_setup)
return;
for (p = common_list; p->dirname; p++)
add_to_trie(&common_trie, p->dirname, p);
common_trie_done_setup = 1;
}
/*
* Helper function for update_common_dir: returns 1 if the dir
* prefix is common.
*/
static int check_common(const char *unmatched, void *value, void *baton)
{
struct common_dir *dir = value;
if (!dir)
return 0;
if (dir->is_dir && (unmatched[0] == 0 || unmatched[0] == '/'))
return !dir->exclude;
if (!dir->is_dir && unmatched[0] == 0)
return !dir->exclude;
return 0;
}
static void update_common_dir(struct strbuf *buf, int git_dir_len)
{
char *base = buf->buf + git_dir_len;
init_common_trie();
if (trie_find(&common_trie, base, check_common, NULL) > 0)
replace_dir(buf, git_dir_len, get_git_common_dir());
}
void report_linked_checkout_garbage(void)
{
struct strbuf sb = STRBUF_INIT;
const char **p;
const struct common_dir *p;
int len;
if (!git_common_dir_env)
return;
strbuf_addf(&sb, "%s/", get_git_dir());
len = sb.len;
for (p = common_list; *p; p++) {
const char *path = *p;
if (*path == '!')
for (p = common_list; p->dirname; p++) {
const char *path = p->dirname;
if (p->ignore_garbage)
continue;
strbuf_setlen(&sb, len);
strbuf_addstr(&sb, path);
Junio C Hamano
10 years ago