git/path.c
Junio C Hamano ed8794ef7a Merge branch 'lh/systemd-timers'
"git maintenance" scheduler learned to use systemd timers as a
possible backend.

* lh/systemd-timers:
  maintenance: add support for systemd timers on Linux
  maintenance: `git maintenance run` learned `--scheduler=<scheduler>`
  cache.h: Introduce a generic "xdg_config_home_for(…)" function
2021-09-20 15:20:40 -07:00

1559 lines
39 KiB
C

/*
* Utilities for paths and pathnames
*/
#include "cache.h"
#include "repository.h"
#include "strbuf.h"
#include "string-list.h"
#include "dir.h"
#include "worktree.h"
#include "submodule-config.h"
#include "path.h"
#include "packfile.h"
#include "object-store.h"
#include "lockfile.h"
#include "exec-cmd.h"
static int get_st_mode_bits(const char *path, int *mode)
{
struct stat st;
if (lstat(path, &st) < 0)
return -1;
*mode = st.st_mode;
return 0;
}
static char bad_path[] = "/bad-path/";
static struct strbuf *get_pathname(void)
{
static struct strbuf pathname_array[4] = {
STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
};
static int index;
struct strbuf *sb = &pathname_array[index];
index = (index + 1) % ARRAY_SIZE(pathname_array);
strbuf_reset(sb);
return sb;
}
static const char *cleanup_path(const char *path)
{
/* Clean it up */
if (skip_prefix(path, "./", &path)) {
while (*path == '/')
path++;
}
return path;
}
static void strbuf_cleanup_path(struct strbuf *sb)
{
const char *path = cleanup_path(sb->buf);
if (path > sb->buf)
strbuf_remove(sb, 0, path - sb->buf);
}
char *mksnpath(char *buf, size_t n, const char *fmt, ...)
{
va_list args;
unsigned len;
va_start(args, fmt);
len = vsnprintf(buf, n, fmt, args);
va_end(args);
if (len >= n) {
strlcpy(buf, bad_path, n);
return buf;
}
return (char *)cleanup_path(buf);
}
static int dir_prefix(const char *buf, const char *dir)
{
int len = strlen(dir);
return !strncmp(buf, dir, len) &&
(is_dir_sep(buf[len]) || buf[len] == '\0');
}
/* $buf =~ m|$dir/+$file| but without regex */
static int is_dir_file(const char *buf, const char *dir, const char *file)
{
int len = strlen(dir);
if (strncmp(buf, dir, len) || !is_dir_sep(buf[len]))
return 0;
while (is_dir_sep(buf[len]))
len++;
return !strcmp(buf + len, file);
}
static void replace_dir(struct strbuf *buf, int len, const char *newdir)
{
int newlen = strlen(newdir);
int need_sep = (buf->buf[len] && !is_dir_sep(buf->buf[len])) &&
!is_dir_sep(newdir[newlen - 1]);
if (need_sep)
len--; /* keep one char, to be replaced with '/' */
strbuf_splice(buf, 0, len, newdir, newlen);
if (need_sep)
buf->buf[newlen] = '/';
}
struct common_dir {
/* Not considered garbage for report_linked_checkout_garbage */
unsigned ignore_garbage:1;
unsigned is_dir:1;
/* Belongs to the common dir, though it may contain paths that don't */
unsigned is_common:1;
const char *path;
};
static struct common_dir common_list[] = {
{ 0, 1, 1, "branches" },
{ 0, 1, 1, "common" },
{ 0, 1, 1, "hooks" },
{ 0, 1, 1, "info" },
{ 0, 0, 0, "info/sparse-checkout" },
{ 1, 1, 1, "logs" },
{ 1, 0, 0, "logs/HEAD" },
{ 0, 1, 0, "logs/refs/bisect" },
{ 0, 1, 0, "logs/refs/rewritten" },
{ 0, 1, 0, "logs/refs/worktree" },
{ 0, 1, 1, "lost-found" },
{ 0, 1, 1, "objects" },
{ 0, 1, 1, "refs" },
{ 0, 1, 0, "refs/bisect" },
{ 0, 1, 0, "refs/rewritten" },
{ 0, 1, 0, "refs/worktree" },
{ 0, 1, 1, "remotes" },
{ 0, 1, 1, "worktrees" },
{ 0, 1, 1, "rr-cache" },
{ 0, 1, 1, "svn" },
{ 0, 0, 1, "config" },
{ 1, 0, 1, "gc.pid" },
{ 0, 0, 1, "packed-refs" },
{ 0, 0, 1, "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 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)
{
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 = xmalloc(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);
}
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;
}
}
old = root->value;
root->value = value;
return old;
}
typedef int (*match_fn)(const char *unmatched, void *value, 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. If there is
* no such prefix, return -1. Otherwise call fn with the unmatched
* portion of the key and the found value. If fn returns 0 or
* positive, then return its return value. If fn returns negative,
* then call fn with the next-longest /-terminated prefix of the key
* (i.e. a parent directory) for which the trie contains a value, and
* handle its return value the same way. If there is no shorter
* /-terminated prefix with a value left, then return the negative
* return value of the most recent fn invocation.
*
* The key is partially normalized: consecutive slashes are skipped.
*
* For example, consider the trie containing only [logs,
* logs/refs/bisect], both with values, but not logs/refs.
*
* | key | unmatched | prefix to node | return value |
* |--------------------|----------------|------------------|--------------|
* | a | not called | n/a | -1 |
* | logstore | not called | n/a | -1 |
* | logs | \0 | logs | as per fn |
* | logs/ | / | logs | as per fn |
* | logs/refs | /refs | logs | as per fn |
* | logs/refs/ | /refs/ | logs | as per fn |
* | logs/refs/b | /refs/b | logs | as per fn |
* | logs/refs/bisected | /refs/bisected | logs | as per fn |
* | logs/refs/bisect | \0 | logs/refs/bisect | as per fn |
* | logs/refs/bisect/ | / | logs/refs/bisect | as per fn |
* | logs/refs/bisect/a | /a | logs/refs/bisect | as per fn |
* | (If fn in the previous line returns -1, then fn is called once more:) |
* | logs/refs/bisect/a | /refs/bisect/a | logs | 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 */
if (root->value)
return fn(key, root->value, baton);
else
return -1;
}
/* 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->path; p++)
add_to_trie(&common_trie, p->path, 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->is_dir && (unmatched[0] == 0 || unmatched[0] == '/'))
return dir->is_common;
if (!dir->is_dir && unmatched[0] == 0)
return dir->is_common;
return 0;
}
static void update_common_dir(struct strbuf *buf, int git_dir_len,
const char *common_dir)
{
char *base = buf->buf + git_dir_len;
int has_lock_suffix = strbuf_strip_suffix(buf, LOCK_SUFFIX);
init_common_trie();
if (trie_find(&common_trie, base, check_common, NULL) > 0)
replace_dir(buf, git_dir_len, common_dir);
if (has_lock_suffix)
strbuf_addstr(buf, LOCK_SUFFIX);
}
void report_linked_checkout_garbage(void)
{
struct strbuf sb = STRBUF_INIT;
const struct common_dir *p;
int len;
if (!the_repository->different_commondir)
return;
strbuf_addf(&sb, "%s/", get_git_dir());
len = sb.len;
for (p = common_list; p->path; p++) {
const char *path = p->path;
if (p->ignore_garbage)
continue;
strbuf_setlen(&sb, len);
strbuf_addstr(&sb, path);
if (file_exists(sb.buf))
report_garbage(PACKDIR_FILE_GARBAGE, sb.buf);
}
strbuf_release(&sb);
}
static void adjust_git_path(const struct repository *repo,
struct strbuf *buf, int git_dir_len)
{
const char *base = buf->buf + git_dir_len;
if (is_dir_file(base, "info", "grafts"))
strbuf_splice(buf, 0, buf->len,
repo->graft_file, strlen(repo->graft_file));
else if (!strcmp(base, "index"))
strbuf_splice(buf, 0, buf->len,
repo->index_file, strlen(repo->index_file));
else if (dir_prefix(base, "objects"))
replace_dir(buf, git_dir_len + 7, repo->objects->odb->path);
else if (git_hooks_path && dir_prefix(base, "hooks"))
replace_dir(buf, git_dir_len + 5, git_hooks_path);
else if (repo->different_commondir)
update_common_dir(buf, git_dir_len, repo->commondir);
}
static void strbuf_worktree_gitdir(struct strbuf *buf,
const struct repository *repo,
const struct worktree *wt)
{
if (!wt)
strbuf_addstr(buf, repo->gitdir);
else if (!wt->id)
strbuf_addstr(buf, repo->commondir);
else
strbuf_git_common_path(buf, repo, "worktrees/%s", wt->id);
}
static void do_git_path(const struct repository *repo,
const struct worktree *wt, struct strbuf *buf,
const char *fmt, va_list args)
{
int gitdir_len;
strbuf_worktree_gitdir(buf, repo, wt);
if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
strbuf_addch(buf, '/');
gitdir_len = buf->len;
strbuf_vaddf(buf, fmt, args);
if (!wt)
adjust_git_path(repo, buf, gitdir_len);
strbuf_cleanup_path(buf);
}
char *repo_git_path(const struct repository *repo,
const char *fmt, ...)
{
struct strbuf path = STRBUF_INIT;
va_list args;
va_start(args, fmt);
do_git_path(repo, NULL, &path, fmt, args);
va_end(args);
return strbuf_detach(&path, NULL);
}
void strbuf_repo_git_path(struct strbuf *sb,
const struct repository *repo,
const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
do_git_path(repo, NULL, sb, fmt, args);
va_end(args);
}
char *git_path_buf(struct strbuf *buf, const char *fmt, ...)
{
va_list args;
strbuf_reset(buf);
va_start(args, fmt);
do_git_path(the_repository, NULL, buf, fmt, args);
va_end(args);
return buf->buf;
}
void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
do_git_path(the_repository, NULL, sb, fmt, args);
va_end(args);
}
const char *git_path(const char *fmt, ...)
{
struct strbuf *pathname = get_pathname();
va_list args;
va_start(args, fmt);
do_git_path(the_repository, NULL, pathname, fmt, args);
va_end(args);
return pathname->buf;
}
char *git_pathdup(const char *fmt, ...)
{
struct strbuf path = STRBUF_INIT;
va_list args;
va_start(args, fmt);
do_git_path(the_repository, NULL, &path, fmt, args);
va_end(args);
return strbuf_detach(&path, NULL);
}
char *mkpathdup(const char *fmt, ...)
{
struct strbuf sb = STRBUF_INIT;
va_list args;
va_start(args, fmt);
strbuf_vaddf(&sb, fmt, args);
va_end(args);
strbuf_cleanup_path(&sb);
return strbuf_detach(&sb, NULL);
}
const char *mkpath(const char *fmt, ...)
{
va_list args;
struct strbuf *pathname = get_pathname();
va_start(args, fmt);
strbuf_vaddf(pathname, fmt, args);
va_end(args);
return cleanup_path(pathname->buf);
}
const char *worktree_git_path(const struct worktree *wt, const char *fmt, ...)
{
struct strbuf *pathname = get_pathname();
va_list args;
va_start(args, fmt);
do_git_path(the_repository, wt, pathname, fmt, args);
va_end(args);
return pathname->buf;
}
static void do_worktree_path(const struct repository *repo,
struct strbuf *buf,
const char *fmt, va_list args)
{
strbuf_addstr(buf, repo->worktree);
if(buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
strbuf_addch(buf, '/');
strbuf_vaddf(buf, fmt, args);
strbuf_cleanup_path(buf);
}
char *repo_worktree_path(const struct repository *repo, const char *fmt, ...)
{
struct strbuf path = STRBUF_INIT;
va_list args;
if (!repo->worktree)
return NULL;
va_start(args, fmt);
do_worktree_path(repo, &path, fmt, args);
va_end(args);
return strbuf_detach(&path, NULL);
}
void strbuf_repo_worktree_path(struct strbuf *sb,
const struct repository *repo,
const char *fmt, ...)
{
va_list args;
if (!repo->worktree)
return;
va_start(args, fmt);
do_worktree_path(repo, sb, fmt, args);
va_end(args);
}
/* Returns 0 on success, negative on failure. */
static int do_submodule_path(struct strbuf *buf, const char *path,
const char *fmt, va_list args)
{
struct strbuf git_submodule_common_dir = STRBUF_INIT;
struct strbuf git_submodule_dir = STRBUF_INIT;
int ret;
ret = submodule_to_gitdir(&git_submodule_dir, path);
if (ret)
goto cleanup;
strbuf_complete(&git_submodule_dir, '/');
strbuf_addbuf(buf, &git_submodule_dir);
strbuf_vaddf(buf, fmt, args);
if (get_common_dir_noenv(&git_submodule_common_dir, git_submodule_dir.buf))
update_common_dir(buf, git_submodule_dir.len, git_submodule_common_dir.buf);
strbuf_cleanup_path(buf);
cleanup:
strbuf_release(&git_submodule_dir);
strbuf_release(&git_submodule_common_dir);
return ret;
}
char *git_pathdup_submodule(const char *path, const char *fmt, ...)
{
int err;
va_list args;
struct strbuf buf = STRBUF_INIT;
va_start(args, fmt);
err = do_submodule_path(&buf, path, fmt, args);
va_end(args);
if (err) {
strbuf_release(&buf);
return NULL;
}
return strbuf_detach(&buf, NULL);
}
int strbuf_git_path_submodule(struct strbuf *buf, const char *path,
const char *fmt, ...)
{
int err;
va_list args;
va_start(args, fmt);
err = do_submodule_path(buf, path, fmt, args);
va_end(args);
return err;
}
static void do_git_common_path(const struct repository *repo,
struct strbuf *buf,
const char *fmt,
va_list args)
{
strbuf_addstr(buf, repo->commondir);
if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
strbuf_addch(buf, '/');
strbuf_vaddf(buf, fmt, args);
strbuf_cleanup_path(buf);
}
const char *git_common_path(const char *fmt, ...)
{
struct strbuf *pathname = get_pathname();
va_list args;
va_start(args, fmt);
do_git_common_path(the_repository, pathname, fmt, args);
va_end(args);
return pathname->buf;
}
void strbuf_git_common_path(struct strbuf *sb,
const struct repository *repo,
const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
do_git_common_path(repo, sb, fmt, args);
va_end(args);
}
int validate_headref(const char *path)
{
struct stat st;
char buffer[256];
const char *refname;
struct object_id oid;
int fd;
ssize_t len;
if (lstat(path, &st) < 0)
return -1;
/* Make sure it is a "refs/.." symlink */
if (S_ISLNK(st.st_mode)) {
len = readlink(path, buffer, sizeof(buffer)-1);
if (len >= 5 && !memcmp("refs/", buffer, 5))
return 0;
return -1;
}
/*
* Anything else, just open it and try to see if it is a symbolic ref.
*/
fd = open(path, O_RDONLY);
if (fd < 0)
return -1;
len = read_in_full(fd, buffer, sizeof(buffer)-1);
close(fd);
if (len < 0)
return -1;
buffer[len] = '\0';
/*
* Is it a symbolic ref?
*/
if (skip_prefix(buffer, "ref:", &refname)) {
while (isspace(*refname))
refname++;
if (starts_with(refname, "refs/"))
return 0;
}
/*
* Is this a detached HEAD?
*/
if (!get_oid_hex(buffer, &oid))
return 0;
return -1;
}
static struct passwd *getpw_str(const char *username, size_t len)
{
struct passwd *pw;
char *username_z = xmemdupz(username, len);
pw = getpwnam(username_z);
free(username_z);
return pw;
}
/*
* Return a string with ~ and ~user expanded via getpw*. Returns NULL on getpw
* failure or if path is NULL.
*
* If real_home is true, strbuf_realpath($HOME) is used in the `~/` expansion.
*
* If the path starts with `%(prefix)/`, the remainder is interpreted as
* relative to where Git is installed, and expanded to the absolute path.
*/
char *interpolate_path(const char *path, int real_home)
{
struct strbuf user_path = STRBUF_INIT;
const char *to_copy = path;
if (path == NULL)
goto return_null;
if (skip_prefix(path, "%(prefix)/", &path))
return system_path(path);
if (path[0] == '~') {
const char *first_slash = strchrnul(path, '/');
const char *username = path + 1;
size_t username_len = first_slash - username;
if (username_len == 0) {
const char *home = getenv("HOME");
if (!home)
goto return_null;
if (real_home)
strbuf_add_real_path(&user_path, home);
else
strbuf_addstr(&user_path, home);
#ifdef GIT_WINDOWS_NATIVE
convert_slashes(user_path.buf);
#endif
} else {
struct passwd *pw = getpw_str(username, username_len);
if (!pw)
goto return_null;
strbuf_addstr(&user_path, pw->pw_dir);
}
to_copy = first_slash;
}
strbuf_addstr(&user_path, to_copy);
return strbuf_detach(&user_path, NULL);
return_null:
strbuf_release(&user_path);
return NULL;
}
/*
* First, one directory to try is determined by the following algorithm.
*
* (0) If "strict" is given, the path is used as given and no DWIM is
* done. Otherwise:
* (1) "~/path" to mean path under the running user's home directory;
* (2) "~user/path" to mean path under named user's home directory;
* (3) "relative/path" to mean cwd relative directory; or
* (4) "/absolute/path" to mean absolute directory.
*
* Unless "strict" is given, we check "%s/.git", "%s", "%s.git/.git", "%s.git"
* in this order. We select the first one that is a valid git repository, and
* chdir() to it. If none match, or we fail to chdir, we return NULL.
*
* If all goes well, we return the directory we used to chdir() (but
* before ~user is expanded), avoiding getcwd() resolving symbolic
* links. User relative paths are also returned as they are given,
* except DWIM suffixing.
*/
const char *enter_repo(const char *path, int strict)
{
static struct strbuf validated_path = STRBUF_INIT;
static struct strbuf used_path = STRBUF_INIT;
if (!path)
return NULL;
if (!strict) {
static const char *suffix[] = {
"/.git", "", ".git/.git", ".git", NULL,
};
const char *gitfile;
int len = strlen(path);
int i;
while ((1 < len) && (path[len-1] == '/'))
len--;
/*
* We can handle arbitrary-sized buffers, but this remains as a
* sanity check on untrusted input.
*/
if (PATH_MAX <= len)
return NULL;
strbuf_reset(&used_path);
strbuf_reset(&validated_path);
strbuf_add(&used_path, path, len);
strbuf_add(&validated_path, path, len);
if (used_path.buf[0] == '~') {
char *newpath = interpolate_path(used_path.buf, 0);
if (!newpath)
return NULL;
strbuf_attach(&used_path, newpath, strlen(newpath),
strlen(newpath));
}
for (i = 0; suffix[i]; i++) {
struct stat st;
size_t baselen = used_path.len;
strbuf_addstr(&used_path, suffix[i]);
if (!stat(used_path.buf, &st) &&
(S_ISREG(st.st_mode) ||
(S_ISDIR(st.st_mode) && is_git_directory(used_path.buf)))) {
strbuf_addstr(&validated_path, suffix[i]);
break;
}
strbuf_setlen(&used_path, baselen);
}
if (!suffix[i])
return NULL;
gitfile = read_gitfile(used_path.buf);
if (gitfile) {
strbuf_reset(&used_path);
strbuf_addstr(&used_path, gitfile);
}
if (chdir(used_path.buf))
return NULL;
path = validated_path.buf;
}
else {
const char *gitfile = read_gitfile(path);
if (gitfile)
path = gitfile;
if (chdir(path))
return NULL;
}
if (is_git_directory(".")) {
set_git_dir(".", 0);
check_repository_format(NULL);
return path;
}
return NULL;
}
static int calc_shared_perm(int mode)
{
int tweak;
if (get_shared_repository() < 0)
tweak = -get_shared_repository();
else
tweak = get_shared_repository();
if (!(mode & S_IWUSR))
tweak &= ~0222;
if (mode & S_IXUSR)
/* Copy read bits to execute bits */
tweak |= (tweak & 0444) >> 2;
if (get_shared_repository() < 0)
mode = (mode & ~0777) | tweak;
else
mode |= tweak;
return mode;
}
int adjust_shared_perm(const char *path)
{
int old_mode, new_mode;
if (!get_shared_repository())
return 0;
if (get_st_mode_bits(path, &old_mode) < 0)
return -1;
new_mode = calc_shared_perm(old_mode);
if (S_ISDIR(old_mode)) {
/* Copy read bits to execute bits */
new_mode |= (new_mode & 0444) >> 2;
new_mode |= FORCE_DIR_SET_GID;
}
if (((old_mode ^ new_mode) & ~S_IFMT) &&
chmod(path, (new_mode & ~S_IFMT)) < 0)
return -2;
return 0;
}
void safe_create_dir(const char *dir, int share)
{
if (mkdir(dir, 0777) < 0) {
if (errno != EEXIST) {
perror(dir);
exit(1);
}
}
else if (share && adjust_shared_perm(dir))
die(_("Could not make %s writable by group"), dir);
}
static int have_same_root(const char *path1, const char *path2)
{
int is_abs1, is_abs2;
is_abs1 = is_absolute_path(path1);
is_abs2 = is_absolute_path(path2);
return (is_abs1 && is_abs2 && tolower(path1[0]) == tolower(path2[0])) ||
(!is_abs1 && !is_abs2);
}
/*
* Give path as relative to prefix.
*
* The strbuf may or may not be used, so do not assume it contains the
* returned path.
*/
const char *relative_path(const char *in, const char *prefix,
struct strbuf *sb)
{
int in_len = in ? strlen(in) : 0;
int prefix_len = prefix ? strlen(prefix) : 0;
int in_off = 0;
int prefix_off = 0;
int i = 0, j = 0;
if (!in_len)
return "./";
else if (!prefix_len)
return in;
if (have_same_root(in, prefix))
/* bypass dos_drive, for "c:" is identical to "C:" */
i = j = has_dos_drive_prefix(in);
else {
return in;
}
while (i < prefix_len && j < in_len && prefix[i] == in[j]) {
if (is_dir_sep(prefix[i])) {
while (is_dir_sep(prefix[i]))
i++;
while (is_dir_sep(in[j]))
j++;
prefix_off = i;
in_off = j;
} else {
i++;
j++;
}
}
if (
/* "prefix" seems like prefix of "in" */
i >= prefix_len &&
/*
* but "/foo" is not a prefix of "/foobar"
* (i.e. prefix not end with '/')
*/
prefix_off < prefix_len) {
if (j >= in_len) {
/* in="/a/b", prefix="/a/b" */
in_off = in_len;
} else if (is_dir_sep(in[j])) {
/* in="/a/b/c", prefix="/a/b" */
while (is_dir_sep(in[j]))
j++;
in_off = j;
} else {
/* in="/a/bbb/c", prefix="/a/b" */
i = prefix_off;
}
} else if (
/* "in" is short than "prefix" */
j >= in_len &&
/* "in" not end with '/' */
in_off < in_len) {
if (is_dir_sep(prefix[i])) {
/* in="/a/b", prefix="/a/b/c/" */
while (is_dir_sep(prefix[i]))
i++;
in_off = in_len;
}
}
in += in_off;
in_len -= in_off;
if (i >= prefix_len) {
if (!in_len)
return "./";
else
return in;
}
strbuf_reset(sb);
strbuf_grow(sb, in_len);
while (i < prefix_len) {
if (is_dir_sep(prefix[i])) {
strbuf_addstr(sb, "../");
while (is_dir_sep(prefix[i]))
i++;
continue;
}
i++;
}
if (!is_dir_sep(prefix[prefix_len - 1]))
strbuf_addstr(sb, "../");
strbuf_addstr(sb, in);
return sb->buf;
}
/*
* A simpler implementation of relative_path
*
* Get relative path by removing "prefix" from "in". This function
* first appears in v1.5.6-1-g044bbbc, and makes git_dir shorter
* to increase performance when traversing the path to work_tree.
*/
const char *remove_leading_path(const char *in, const char *prefix)
{
static struct strbuf buf = STRBUF_INIT;
int i = 0, j = 0;
if (!prefix || !prefix[0])
return in;
while (prefix[i]) {
if (is_dir_sep(prefix[i])) {
if (!is_dir_sep(in[j]))
return in;
while (is_dir_sep(prefix[i]))
i++;
while (is_dir_sep(in[j]))
j++;
continue;
} else if (in[j] != prefix[i]) {
return in;
}
i++;
j++;
}
if (
/* "/foo" is a prefix of "/foo" */
in[j] &&
/* "/foo" is not a prefix of "/foobar" */
!is_dir_sep(prefix[i-1]) && !is_dir_sep(in[j])
)
return in;
while (is_dir_sep(in[j]))
j++;
strbuf_reset(&buf);
if (!in[j])
strbuf_addstr(&buf, ".");
else
strbuf_addstr(&buf, in + j);
return buf.buf;
}
/*
* It is okay if dst == src, but they should not overlap otherwise.
* The "dst" buffer must be at least as long as "src"; normalizing may shrink
* the size of the path, but will never grow it.
*
* Performs the following normalizations on src, storing the result in dst:
* - Ensures that components are separated by '/' (Windows only)
* - Squashes sequences of '/' except "//server/share" on Windows
* - Removes "." components.
* - Removes ".." components, and the components the precede them.
* Returns failure (non-zero) if a ".." component appears as first path
* component anytime during the normalization. Otherwise, returns success (0).
*
* Note that this function is purely textual. It does not follow symlinks,
* verify the existence of the path, or make any system calls.
*
* prefix_len != NULL is for a specific case of prefix_pathspec():
* assume that src == dst and src[0..prefix_len-1] is already
* normalized, any time "../" eats up to the prefix_len part,
* prefix_len is reduced. In the end prefix_len is the remaining
* prefix that has not been overridden by user pathspec.
*
* NEEDSWORK: This function doesn't perform normalization w.r.t. trailing '/'.
* For everything but the root folder itself, the normalized path should not
* end with a '/', then the callers need to be fixed up accordingly.
*
*/
int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
{
char *dst0;
const char *end;
/*
* Copy initial part of absolute path: "/", "C:/", "//server/share/".
*/
end = src + offset_1st_component(src);
while (src < end) {
char c = *src++;
if (is_dir_sep(c))
c = '/';
*dst++ = c;
}
dst0 = dst;
while (is_dir_sep(*src))
src++;
for (;;) {
char c = *src;
/*
* A path component that begins with . could be
* special:
* (1) "." and ends -- ignore and terminate.
* (2) "./" -- ignore them, eat slash and continue.
* (3) ".." and ends -- strip one and terminate.
* (4) "../" -- strip one, eat slash and continue.
*/
if (c == '.') {
if (!src[1]) {
/* (1) */
src++;
} else if (is_dir_sep(src[1])) {
/* (2) */
src += 2;
while (is_dir_sep(*src))
src++;
continue;
} else if (src[1] == '.') {
if (!src[2]) {
/* (3) */
src += 2;
goto up_one;
} else if (is_dir_sep(src[2])) {
/* (4) */
src += 3;
while (is_dir_sep(*src))
src++;
goto up_one;
}
}
}
/* copy up to the next '/', and eat all '/' */
while ((c = *src++) != '\0' && !is_dir_sep(c))
*dst++ = c;
if (is_dir_sep(c)) {
*dst++ = '/';
while (is_dir_sep(c))
c = *src++;
src--;
} else if (!c)
break;
continue;
up_one:
/*
* dst0..dst is prefix portion, and dst[-1] is '/';
* go up one level.
*/
dst--; /* go to trailing '/' */
if (dst <= dst0)
return -1;
/* Windows: dst[-1] cannot be backslash anymore */
while (dst0 < dst && dst[-1] != '/')
dst--;
if (prefix_len && *prefix_len > dst - dst0)
*prefix_len = dst - dst0;
}
*dst = '\0';
return 0;
}
int normalize_path_copy(char *dst, const char *src)
{
return normalize_path_copy_len(dst, src, NULL);
}
/*
* path = Canonical absolute path
* prefixes = string_list containing normalized, absolute paths without
* trailing slashes (except for the root directory, which is denoted by "/").
*
* Determines, for each path in prefixes, whether the "prefix"
* is an ancestor directory of path. Returns the length of the longest
* ancestor directory, excluding any trailing slashes, or -1 if no prefix
* is an ancestor. (Note that this means 0 is returned if prefixes is
* ["/"].) "/foo" is not considered an ancestor of "/foobar". Directories
* are not considered to be their own ancestors. path must be in a
* canonical form: empty components, or "." or ".." components are not
* allowed.
*/
int longest_ancestor_length(const char *path, struct string_list *prefixes)
{
int i, max_len = -1;
if (!strcmp(path, "/"))
return -1;
for (i = 0; i < prefixes->nr; i++) {
const char *ceil = prefixes->items[i].string;
int len = strlen(ceil);
if (len == 1 && ceil[0] == '/')
len = 0; /* root matches anything, with length 0 */
else if (!strncmp(path, ceil, len) && path[len] == '/')
; /* match of length len */
else
continue; /* no match */
if (len > max_len)
max_len = len;
}
return max_len;
}
/* strip arbitrary amount of directory separators at end of path */
static inline int chomp_trailing_dir_sep(const char *path, int len)
{
while (len && is_dir_sep(path[len - 1]))
len--;
return len;
}
/*
* If path ends with suffix (complete path components), returns the offset of
* the last character in the path before the suffix (sans trailing directory
* separators), and -1 otherwise.
*/
static ssize_t stripped_path_suffix_offset(const char *path, const char *suffix)
{
int path_len = strlen(path), suffix_len = strlen(suffix);
while (suffix_len) {
if (!path_len)
return -1;
if (is_dir_sep(path[path_len - 1])) {
if (!is_dir_sep(suffix[suffix_len - 1]))
return -1;
path_len = chomp_trailing_dir_sep(path, path_len);
suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
}
else if (path[--path_len] != suffix[--suffix_len])
return -1;
}
if (path_len && !is_dir_sep(path[path_len - 1]))
return -1;
return chomp_trailing_dir_sep(path, path_len);
}
/*
* Returns true if the path ends with components, considering only complete path
* components, and false otherwise.
*/
int ends_with_path_components(const char *path, const char *components)
{
return stripped_path_suffix_offset(path, components) != -1;
}
/*
* If path ends with suffix (complete path components), returns the
* part before suffix (sans trailing directory separators).
* Otherwise returns NULL.
*/
char *strip_path_suffix(const char *path, const char *suffix)
{
ssize_t offset = stripped_path_suffix_offset(path, suffix);
return offset == -1 ? NULL : xstrndup(path, offset);
}
int daemon_avoid_alias(const char *p)
{
int sl, ndot;
/*
* This resurrects the belts and suspenders paranoia check by HPA
* done in <435560F7.4080006@zytor.com> thread, now enter_repo()
* does not do getcwd() based path canonicalization.
*
* sl becomes true immediately after seeing '/' and continues to
* be true as long as dots continue after that without intervening
* non-dot character.
*/
if (!p || (*p != '/' && *p != '~'))
return -1;
sl = 1; ndot = 0;
p++;
while (1) {
char ch = *p++;
if (sl) {
if (ch == '.')
ndot++;
else if (ch == '/') {
if (ndot < 3)
/* reject //, /./ and /../ */
return -1;
ndot = 0;
}
else if (ch == 0) {
if (0 < ndot && ndot < 3)
/* reject /.$ and /..$ */
return -1;
return 0;
}
else
sl = ndot = 0;
}
else if (ch == 0)
return 0;
else if (ch == '/') {
sl = 1;
ndot = 0;
}
}
}
/*
* On NTFS, we need to be careful to disallow certain synonyms of the `.git/`
* directory:
*
* - For historical reasons, file names that end in spaces or periods are
* automatically trimmed. Therefore, `.git . . ./` is a valid way to refer
* to `.git/`.
*
* - For other historical reasons, file names that do not conform to the 8.3
* format (up to eight characters for the basename, three for the file
* extension, certain characters not allowed such as `+`, etc) are associated
* with a so-called "short name", at least on the `C:` drive by default.
* Which means that `git~1/` is a valid way to refer to `.git/`.
*
* Note: Technically, `.git/` could receive the short name `git~2` if the
* short name `git~1` were already used. In Git, however, we guarantee that
* `.git` is the first item in a directory, therefore it will be associated
* with the short name `git~1` (unless short names are disabled).
*
* - For yet other historical reasons, NTFS supports so-called "Alternate Data
* Streams", i.e. metadata associated with a given file, referred to via
* `<filename>:<stream-name>:<stream-type>`. There exists a default stream
* type for directories, allowing `.git/` to be accessed via
* `.git::$INDEX_ALLOCATION/`.
*
* When this function returns 1, it indicates that the specified file/directory
* name refers to a `.git` file or directory, or to any of these synonyms, and
* Git should therefore not track it.
*
* For performance reasons, _all_ Alternate Data Streams of `.git/` are
* forbidden, not just `::$INDEX_ALLOCATION`.
*
* This function is intended to be used by `git fsck` even on platforms where
* the backslash is a regular filename character, therefore it needs to handle
* backlash characters in the provided `name` specially: they are interpreted
* as directory separators.
*/
int is_ntfs_dotgit(const char *name)
{
char c;
/*
* Note that when we don't find `.git` or `git~1` we end up with `name`
* advanced partway through the string. That's okay, though, as we
* return immediately in those cases, without looking at `name` any
* further.
*/
c = *(name++);
if (c == '.') {
/* .git */
if (((c = *(name++)) != 'g' && c != 'G') ||
((c = *(name++)) != 'i' && c != 'I') ||
((c = *(name++)) != 't' && c != 'T'))
return 0;
} else if (c == 'g' || c == 'G') {
/* git ~1 */
if (((c = *(name++)) != 'i' && c != 'I') ||
((c = *(name++)) != 't' && c != 'T') ||
*(name++) != '~' ||
*(name++) != '1')
return 0;
} else
return 0;
for (;;) {
c = *(name++);
if (!c || c == '\\' || c == '/' || c == ':')
return 1;
if (c != '.' && c != ' ')
return 0;
}
}
static int is_ntfs_dot_generic(const char *name,
const char *dotgit_name,
size_t len,
const char *dotgit_ntfs_shortname_prefix)
{
int saw_tilde;
size_t i;
if ((name[0] == '.' && !strncasecmp(name + 1, dotgit_name, len))) {
i = len + 1;
only_spaces_and_periods:
for (;;) {
char c = name[i++];
if (!c || c == ':')
return 1;
if (c != ' ' && c != '.')
return 0;
}
}
/*
* Is it a regular NTFS short name, i.e. shortened to 6 characters,
* followed by ~1, ... ~4?
*/
if (!strncasecmp(name, dotgit_name, 6) && name[6] == '~' &&
name[7] >= '1' && name[7] <= '4') {
i = 8;
goto only_spaces_and_periods;
}
/*
* Is it a fall-back NTFS short name (for details, see
* https://en.wikipedia.org/wiki/8.3_filename?
*/
for (i = 0, saw_tilde = 0; i < 8; i++)
if (name[i] == '\0')
return 0;
else if (saw_tilde) {
if (name[i] < '0' || name[i] > '9')
return 0;
} else if (name[i] == '~') {
if (name[++i] < '1' || name[i] > '9')
return 0;
saw_tilde = 1;
} else if (i >= 6)
return 0;
else if (name[i] & 0x80) {
/*
* We know our needles contain only ASCII, so we clamp
* here to make the results of tolower() sane.
*/
return 0;
} else if (tolower(name[i]) != dotgit_ntfs_shortname_prefix[i])
return 0;
goto only_spaces_and_periods;
}
/*
* Inline helper to make sure compiler resolves strlen() on literals at
* compile time.
*/
static inline int is_ntfs_dot_str(const char *name, const char *dotgit_name,
const char *dotgit_ntfs_shortname_prefix)
{
return is_ntfs_dot_generic(name, dotgit_name, strlen(dotgit_name),
dotgit_ntfs_shortname_prefix);
}
int is_ntfs_dotgitmodules(const char *name)
{
return is_ntfs_dot_str(name, "gitmodules", "gi7eba");
}
int is_ntfs_dotgitignore(const char *name)
{
return is_ntfs_dot_str(name, "gitignore", "gi250a");
}
int is_ntfs_dotgitattributes(const char *name)
{
return is_ntfs_dot_str(name, "gitattributes", "gi7d29");
}
int is_ntfs_dotmailmap(const char *name)
{
return is_ntfs_dot_str(name, "mailmap", "maba30");
}
int looks_like_command_line_option(const char *str)
{
return str && str[0] == '-';
}
char *xdg_config_home_for(const char *subdir, const char *filename)
{
const char *home, *config_home;
assert(subdir);
assert(filename);
config_home = getenv("XDG_CONFIG_HOME");
if (config_home && *config_home)
return mkpathdup("%s/%s/%s", config_home, subdir, filename);
home = getenv("HOME");
if (home)
return mkpathdup("%s/.config/%s/%s", home, subdir, filename);
return NULL;
}
char *xdg_config_home(const char *filename)
{
return xdg_config_home_for("git", filename);
}
char *xdg_cache_home(const char *filename)
{
const char *home, *cache_home;
assert(filename);
cache_home = getenv("XDG_CACHE_HOME");
if (cache_home && *cache_home)
return mkpathdup("%s/git/%s", cache_home, filename);
home = getenv("HOME");
if (home)
return mkpathdup("%s/.cache/git/%s", home, filename);
return NULL;
}
REPO_GIT_PATH_FUNC(squash_msg, "SQUASH_MSG")
REPO_GIT_PATH_FUNC(merge_msg, "MERGE_MSG")
REPO_GIT_PATH_FUNC(merge_rr, "MERGE_RR")
REPO_GIT_PATH_FUNC(merge_mode, "MERGE_MODE")
REPO_GIT_PATH_FUNC(merge_head, "MERGE_HEAD")
REPO_GIT_PATH_FUNC(merge_autostash, "MERGE_AUTOSTASH")
REPO_GIT_PATH_FUNC(auto_merge, "AUTO_MERGE")
REPO_GIT_PATH_FUNC(fetch_head, "FETCH_HEAD")
REPO_GIT_PATH_FUNC(shallow, "shallow")