1 files changed, 217 insertions, 111 deletions

diff --git a/path.c b/path.c
index e608993801..69265f42ce 100644
--- a/path.c
+++ b/path.c
@@ -4,6 +4,7 @@
 #include "cache.h"
 #include "strbuf.h"
 #include "string-list.h"
+#include "dir.h"
 
 static int get_st_mode_bits(const char *path, int *mode)
 {
@@ -16,11 +17,15 @@ static int get_st_mode_bits(const char *path, int *mode)
 
 static char bad_path[] = "/bad-path/";
 
-static char *get_pathname(void)
+static struct strbuf *get_pathname(void)
 {
-	static char pathname_array[4][PATH_MAX];
+	static struct strbuf pathname_array[4] = {
+		STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
+	};
 	static int index;
-	return pathname_array[3 & ++index];
+	struct strbuf *sb = &pathname_array[3 & ++index];
+	strbuf_reset(sb);
+	return sb;
 }
 
 static char *cleanup_path(char *path)
@@ -34,6 +39,13 @@ static char *cleanup_path(char *path)
 	return path;
 }
 
+static void strbuf_cleanup_path(struct strbuf *sb)
+{
+	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;
@@ -49,152 +61,221 @@ char *mksnpath(char *buf, size_t n, const char *fmt, ...)
 	return cleanup_path(buf);
 }
 
-static char *vsnpath(char *buf, size_t n, const char *fmt, va_list args)
+static int dir_prefix(const char *buf, const char *dir)
 {
-	const char *git_dir = get_git_dir();
-	size_t len;
+	int len = strlen(dir);
+	return !strncmp(buf, dir, len) &&
+		(is_dir_sep(buf[len]) || buf[len] == '\0');
+}
 
-	len = strlen(git_dir);
-	if (n < len + 1)
-		goto bad;
-	memcpy(buf, git_dir, len);
-	if (len && !is_dir_sep(git_dir[len-1]))
-		buf[len++] = '/';
-	len += vsnprintf(buf + len, n - len, fmt, args);
-	if (len >= n)
-		goto bad;
-	return cleanup_path(buf);
-bad:
-	strlcpy(buf, bad_path, n);
-	return buf;
+/* $buf =~ m|$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);
 }
 
-char *git_snpath(char *buf, size_t n, const char *fmt, ...)
+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] = '/';
+}
+
+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
+};
+
+static void update_common_dir(struct strbuf *buf, int git_dir_len, const char *common_dir)
+{
+	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;
+		}
+
+		if (!common_dir)
+			common_dir = get_git_common_dir();
+
+		if (is_dir && dir_prefix(base, path)) {
+			replace_dir(buf, git_dir_len, common_dir);
+			return;
+		}
+		if (!is_dir && !strcmp(base, path)) {
+			replace_dir(buf, git_dir_len, common_dir);
+			return;
+		}
+	}
+}
+
+void report_linked_checkout_garbage(void)
+{
+	struct strbuf sb = STRBUF_INIT;
+	const char **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 == '!')
+			continue;
+		strbuf_setlen(&sb, len);
+		strbuf_addstr(&sb, path);
+		if (file_exists(sb.buf))
+			report_garbage("unused in linked checkout", sb.buf);
+	}
+	strbuf_release(&sb);
+}
+
+static void adjust_git_path(struct strbuf *buf, int git_dir_len)
+{
+	const char *base = buf->buf + git_dir_len;
+	if (git_graft_env && is_dir_file(base, "info", "grafts"))
+		strbuf_splice(buf, 0, buf->len,
+			      get_graft_file(), strlen(get_graft_file()));
+	else if (git_index_env && !strcmp(base, "index"))
+		strbuf_splice(buf, 0, buf->len,
+			      get_index_file(), strlen(get_index_file()));
+	else if (git_db_env && dir_prefix(base, "objects"))
+		replace_dir(buf, git_dir_len + 7, get_object_directory());
+	else if (git_common_dir_env)
+		update_common_dir(buf, git_dir_len, NULL);
+}
+
+static void do_git_path(struct strbuf *buf, const char *fmt, va_list args)
+{
+	int gitdir_len;
+	strbuf_addstr(buf, get_git_dir());
+	if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
+		strbuf_addch(buf, '/');
+	gitdir_len = buf->len;
+	strbuf_vaddf(buf, fmt, args);
+	adjust_git_path(buf, gitdir_len);
+	strbuf_cleanup_path(buf);
+}
+
+void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
 {
-	char *ret;
 	va_list args;
 	va_start(args, fmt);
-	ret = vsnpath(buf, n, fmt, args);
+	do_git_path(sb, fmt, args);
 	va_end(args);
-	return ret;
 }
 
-char *git_pathdup(const char *fmt, ...)
+const char *git_path(const char *fmt, ...)
 {
-	char path[PATH_MAX], *ret;
+	struct strbuf *pathname = get_pathname();
 	va_list args;
 	va_start(args, fmt);
-	ret = vsnpath(path, sizeof(path), fmt, args);
+	do_git_path(pathname, fmt, args);
 	va_end(args);
-	return xstrdup(ret);
+	return pathname->buf;
 }
 
-char *mkpathdup(const char *fmt, ...)
+char *git_pathdup(const char *fmt, ...)
 {
-	char *path;
-	struct strbuf sb = STRBUF_INIT;
+	struct strbuf path = STRBUF_INIT;
 	va_list args;
-
 	va_start(args, fmt);
-	strbuf_vaddf(&sb, fmt, args);
+	do_git_path(&path, fmt, args);
 	va_end(args);
-	path = xstrdup(cleanup_path(sb.buf));
-
-	strbuf_release(&sb);
-	return path;
+	return strbuf_detach(&path, NULL);
 }
 
-char *mkpath(const char *fmt, ...)
+char *mkpathdup(const char *fmt, ...)
 {
+	struct strbuf sb = STRBUF_INIT;
 	va_list args;
-	unsigned len;
-	char *pathname = get_pathname();
-
 	va_start(args, fmt);
-	len = vsnprintf(pathname, PATH_MAX, fmt, args);
+	strbuf_vaddf(&sb, fmt, args);
 	va_end(args);
-	if (len >= PATH_MAX)
-		return bad_path;
-	return cleanup_path(pathname);
+	strbuf_cleanup_path(&sb);
+	return strbuf_detach(&sb, NULL);
 }
 
-char *git_path(const char *fmt, ...)
+const char *mkpath(const char *fmt, ...)
 {
-	char *pathname = get_pathname();
 	va_list args;
-	char *ret;
-
+	struct strbuf *pathname = get_pathname();
 	va_start(args, fmt);
-	ret = vsnpath(pathname, PATH_MAX, fmt, args);
+	strbuf_vaddf(pathname, fmt, args);
 	va_end(args);
-	return ret;
+	return cleanup_path(pathname->buf);
 }
 
-void home_config_paths(char **global, char **xdg, char *file)
+static void do_submodule_path(struct strbuf *buf, const char *path,
+			      const char *fmt, va_list args)
 {
-	char *xdg_home = getenv("XDG_CONFIG_HOME");
-	char *home = getenv("HOME");
-	char *to_free = NULL;
+	const char *git_dir;
+	struct strbuf git_submodule_common_dir = STRBUF_INIT;
+	struct strbuf git_submodule_dir = STRBUF_INIT;
 
-	if (!home) {
-		if (global)
-			*global = NULL;
-	} else {
-		if (!xdg_home) {
-			to_free = mkpathdup("%s/.config", home);
-			xdg_home = to_free;
-		}
-		if (global)
-			*global = mkpathdup("%s/.gitconfig", home);
-	}
+	strbuf_addstr(buf, path);
+	if (buf->len && buf->buf[buf->len - 1] != '/')
+		strbuf_addch(buf, '/');
+	strbuf_addstr(buf, ".git");
 
-	if (xdg) {
-		if (!xdg_home)
-			*xdg = NULL;
-		else
-			*xdg = mkpathdup("%s/git/%s", xdg_home, file);
+	git_dir = read_gitfile(buf->buf);
+	if (git_dir) {
+		strbuf_reset(buf);
+		strbuf_addstr(buf, git_dir);
 	}
+	strbuf_addch(buf, '/');
+	strbuf_addstr(&git_submodule_dir, buf->buf);
 
-	free(to_free);
-}
+	strbuf_vaddf(buf, fmt, args);
 
-char *git_path_submodule(const char *path, const char *fmt, ...)
-{
-	char *pathname = get_pathname();
-	struct strbuf buf = STRBUF_INIT;
-	const char *git_dir;
-	va_list args;
-	unsigned len;
+	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);
 
-	len = strlen(path);
-	if (len > PATH_MAX-100)
-		return bad_path;
+	strbuf_cleanup_path(buf);
 
-	strbuf_addstr(&buf, path);
-	if (len && path[len-1] != '/')
-		strbuf_addch(&buf, '/');
-	strbuf_addstr(&buf, ".git");
-
-	git_dir = read_gitfile(buf.buf);
-	if (git_dir) {
-		strbuf_reset(&buf);
-		strbuf_addstr(&buf, git_dir);
-	}
-	strbuf_addch(&buf, '/');
-
-	if (buf.len >= PATH_MAX)
-		return bad_path;
-	memcpy(pathname, buf.buf, buf.len + 1);
+	strbuf_release(&git_submodule_dir);
+	strbuf_release(&git_submodule_common_dir);
+}
 
-	strbuf_release(&buf);
-	len = strlen(pathname);
+char *git_pathdup_submodule(const char *path, const char *fmt, ...)
+{
+	va_list args;
+	struct strbuf buf = STRBUF_INIT;
+	va_start(args, fmt);
+	do_submodule_path(&buf, path, fmt, args);
+	va_end(args);
+	return strbuf_detach(&buf, NULL);
+}
 
+void strbuf_git_path_submodule(struct strbuf *buf, const char *path,
+			       const char *fmt, ...)
+{
+	va_list args;
 	va_start(args, fmt);
-	len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
+	do_submodule_path(buf, path, fmt, args);
 	va_end(args);
-	if (len >= PATH_MAX)
-		return bad_path;
-	return cleanup_path(pathname);
 }
 
 int validate_headref(const char *path)
@@ -303,14 +384,9 @@ return_null:
  * (3) "relative/path" to mean cwd relative directory; or
  * (4) "/absolute/path" to mean absolute directory.
  *
- * Unless "strict" is given, we try access() for existence of "%s.git/.git",
- * "%s/.git", "%s.git", "%s" in this order.  The first one that exists is
- * what we try.
- *
- * Second, we try chdir() to that.  Upon failure, we return NULL.
- *
- * Then, we try if the current directory is a valid git repository.
- * Upon failure, we return NULL.
+ * 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
@@ -614,6 +690,11 @@ const char *remove_leading_path(const char *in, const char *prefix)
  * 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)
 {
@@ -856,3 +937,28 @@ int is_ntfs_dotgit(const char *name)
 			len = -1;
 		}
 }
+
+char *xdg_config_home(const char *filename)
+{
+	const char *home, *config_home;
+
+	assert(filename);
+	config_home = getenv("XDG_CONFIG_HOME");
+	if (config_home && *config_home)
+		return mkpathdup("%s/git/%s", config_home, filename);
+
+	home = getenv("HOME");
+	if (home)
+		return mkpathdup("%s/.config/git/%s", home, filename);
+	return NULL;
+}
+
+GIT_PATH_FUNC(git_path_cherry_pick_head, "CHERRY_PICK_HEAD")
+GIT_PATH_FUNC(git_path_revert_head, "REVERT_HEAD")
+GIT_PATH_FUNC(git_path_squash_msg, "SQUASH_MSG")
+GIT_PATH_FUNC(git_path_merge_msg, "MERGE_MSG")
+GIT_PATH_FUNC(git_path_merge_rr, "MERGE_RR")
+GIT_PATH_FUNC(git_path_merge_mode, "MERGE_MODE")
+GIT_PATH_FUNC(git_path_merge_head, "MERGE_HEAD")
+GIT_PATH_FUNC(git_path_fetch_head, "FETCH_HEAD")
+GIT_PATH_FUNC(git_path_shallow, "shallow")