Provide more meaningful output from 'git init-db'.

Back in the old days of Git when people messed around with their
GIT_DIR environment variable more often it was nice to know whether
or not git-init-db created a .git directory or used GIT_DIR.
As most users at that time were rather technical UNIXy folk the
message "defaulting to local storage area" made sense to some and
seemed reasonable.

But it doesn't really convey any meaning to the new Git user,
as they don't know what a 'local storage area is' nor do they
know enough about Git to care.  It also really doesn't tell the
experienced Git user a whole lot about the command they just ran,
especially if they might be reinitializing an existing repository
(e.g. to update hooks).

So now we print out what we did ("Initialized empty" or
"Reinitialized existing"), what type of repository ("" or "shared"),
and what location the repository will be in ("$GIT_DIR").

Suggested in part by Andy Parkins in his Git 'niggles' list
(<200612132237.10051.andyparkins@gmail.com>).

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/core-tutorial.txt

@@ -57,7 +57,7 @@ $ git-init-db
 to which git will reply
 
 ----------------
-defaulting to local storage area
+Initialized empty Git repository in .git/
 ----------------
 
 which is just git's way of saying that you haven't been doing anything

Documentation/tutorial-2.txt

@@ -18,7 +18,7 @@ Let's start a new project and create a small amount of history:
 $ mkdir test-project
 $ cd test-project
 $ git init-db
-defaulting to local storage area
+Initialized empty Git repository in .git/
 $ echo 'hello world' > file.txt
 $ git add .
 $ git commit -a -m "initial commit"

Documentation/tutorial.txt

@@ -38,7 +38,7 @@ $ git init-db
 Git will reply
 
 ------------------------------------------------
-defaulting to local storage area
+Initialized empty Git repository in .git/
 ------------------------------------------------
 
 You've now initialized the working directory--you may notice a new

builtin-init-db.c

@@ -164,13 +164,14 @@ static void copy_templates(const char *git_dir, int len, const char *template_di
 	closedir(dir);
 }
 
-static void create_default_files(const char *git_dir, const char *template_path)
+static int create_default_files(const char *git_dir, const char *template_path)
 {
 	unsigned len = strlen(git_dir);
 	static char path[PATH_MAX];
 	unsigned char sha1[20];
 	struct stat st1;
 	char repo_version_string[10];
+	int reinit;
 
 	if (len > sizeof(path)-50)
 		die("insane git directory %s", git_dir);
@@ -218,7 +219,8 @@ static void create_default_files(const char *git_dir, const char *template_path)
 	 * branch, if it does not exist yet.
 	 */
 	strcpy(path + len, "HEAD");
-	if (read_ref("HEAD", sha1) < 0) {
+	reinit = !read_ref("HEAD", sha1);
+	if (!reinit) {
 		if (create_symref("HEAD", "refs/heads/master") < 0)
 			exit(1);
 	}
@@ -239,6 +241,8 @@ static void create_default_files(const char *git_dir, const char *template_path)
 		git_config_set("core.filemode",
 			       filemode ? "true" : "false");
 	}
+
+	return reinit;
 }
 
 static const char init_db_usage[] =
@@ -256,7 +260,7 @@ int cmd_init_db(int argc, const char **argv, const char *prefix)
 	const char *sha1_dir;
 	const char *template_dir = NULL;
 	char *path;
-	int len, i;
+	int len, i, reinit;
 
 	for (i = 1; i < argc; i++, argv++) {
 		const char *arg = argv[1];
@@ -274,10 +278,8 @@ int cmd_init_db(int argc, const char **argv, const char *prefix)
 	 * Set up the default .git directory contents
 	 */
 	git_dir = getenv(GIT_DIR_ENVIRONMENT);
-	if (!git_dir) {
+	if (!git_dir)
 		git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
-		fprintf(stderr, "defaulting to local storage area\n");
-	}
 	safe_create_dir(git_dir, 0);
 
 	/* Check to see if the repository version is right.
@@ -287,7 +289,7 @@ int cmd_init_db(int argc, const char **argv, const char *prefix)
 	 */
 	check_repository_format();
 
-	create_default_files(git_dir, template_dir);
+	reinit = create_default_files(git_dir, template_dir);
 
 	/*
 	 * And set up the object store.
@@ -314,5 +316,10 @@ int cmd_init_db(int argc, const char **argv, const char *prefix)
 		git_config_set("receive.denyNonFastforwards", "true");
 	}
 
+	printf("%s%s Git repository in %s/\n",
+		reinit ? "Reinitialized existing" : "Initialized empty",
+		shared_repository ? " shared" : "",
+		git_dir);
+
 	return 0;
 }