path.c: refactor and add worktree_git_path()

do_git_path(), which is the common code for all git_path* functions, is
modified to take a worktree struct and can produce paths for any
worktree.

worktree_git_path() is the first function that makes use of this. It can
be used to write code that can examine any worktree. For example,
wt_status_get_state() will be converted using this to take
am/rebase/... state of any worktree.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: pclouds

path.c

@@ -5,6 +5,7 @@
 #include "strbuf.h"
 #include "string-list.h"
 #include "dir.h"
+#include "worktree.h"
 
 static int get_st_mode_bits(const char *path, int *mode)
 {
@@ -383,10 +384,11 @@ static void adjust_git_path(struct strbuf *buf, int git_dir_len)
 		update_common_dir(buf, git_dir_len, NULL);
 }
 
-static void do_git_path(struct strbuf *buf, const char *fmt, va_list args)
+static void do_git_path(const struct worktree *wt, struct strbuf *buf,
+			const char *fmt, va_list args)
 {
 	int gitdir_len;
-	strbuf_addstr(buf, get_git_dir());
+	strbuf_addstr(buf, get_worktree_git_dir(wt));
 	if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
 		strbuf_addch(buf, '/');
 	gitdir_len = buf->len;
@@ -400,7 +402,7 @@ char *git_path_buf(struct strbuf *buf, const char *fmt, ...)
 	va_list args;
 	strbuf_reset(buf);
 	va_start(args, fmt);
-	do_git_path(buf, fmt, args);
+	do_git_path(NULL, buf, fmt, args);
 	va_end(args);
 	return buf->buf;
 }
@@ -409,7 +411,7 @@ void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
 {
 	va_list args;
 	va_start(args, fmt);
-	do_git_path(sb, fmt, args);
+	do_git_path(NULL, sb, fmt, args);
 	va_end(args);
 }
 
@@ -418,7 +420,7 @@ const char *git_path(const char *fmt, ...)
 	struct strbuf *pathname = get_pathname();
 	va_list args;
 	va_start(args, fmt);
-	do_git_path(pathname, fmt, args);
+	do_git_path(NULL, pathname, fmt, args);
 	va_end(args);
 	return pathname->buf;
 }
@@ -428,7 +430,7 @@ char *git_pathdup(const char *fmt, ...)
 	struct strbuf path = STRBUF_INIT;
 	va_list args;
 	va_start(args, fmt);
-	do_git_path(&path, fmt, args);
+	do_git_path(NULL, &path, fmt, args);
 	va_end(args);
 	return strbuf_detach(&path, NULL);
 }
@@ -454,6 +456,16 @@ const char *mkpath(const char *fmt, ...)
 	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(wt, pathname, fmt, args);
+	va_end(args);
+	return pathname->buf;
+}
+
 static void do_submodule_path(struct strbuf *buf, const char *path,
 			      const char *fmt, va_list args)
 {

worktree.h

@@ -42,4 +42,12 @@ extern void free_worktrees(struct worktree **);
 extern const struct worktree *find_shared_symref(const char *symref,
 						 const char *target);
 
+/*
+ * Similar to git_path() but can produce paths for a specified
+ * worktree instead of current one
+ */
+extern const char *worktree_git_path(const struct worktree *wt,
+				     const char *fmt, ...)
+	__attribute__((format (printf, 2, 3)));
+
 #endif