init: refactor the template directory discovery into its own function

We will need to call this function from `hook.c` to be able to prevent
hooks from running that were written as part of a `clone` but did not
originate from the template directory.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

builtin/init-db.c

@@ -11,10 +11,6 @@
 #include "parse-options.h"
 #include "worktree.h"
 
-#ifndef DEFAULT_GIT_TEMPLATE_DIR
-#define DEFAULT_GIT_TEMPLATE_DIR "/usr/share/git-core/templates"
-#endif
-
 #ifdef NO_TRUSTABLE_FILEMODE
 #define TEST_FILEMODE 0
 #else
@@ -93,8 +89,9 @@ static void copy_templates_1(struct strbuf *path, struct strbuf *template_path,
 	}
 }
 
-static void copy_templates(const char *template_dir, const char *init_template_dir)
+static void copy_templates(const char *option_template)
 {
+	const char *template_dir = get_template_dir(option_template);
 	struct strbuf path = STRBUF_INIT;
 	struct strbuf template_path = STRBUF_INIT;
 	size_t template_len;
@@ -103,16 +100,8 @@ static void copy_templates(const char *template_dir, const char *init_template_d
 	DIR *dir;
 	char *to_free = NULL;
 
-	if (!template_dir)
-		template_dir = getenv(TEMPLATE_DIR_ENVIRONMENT);
-	if (!template_dir)
-		template_dir = init_template_dir;
-	if (!template_dir)
-		template_dir = to_free = system_path(DEFAULT_GIT_TEMPLATE_DIR);
-	if (!template_dir[0]) {
-		free(to_free);
+	if (!template_dir || !*template_dir)
 		return;
-	}
 
 	strbuf_addstr(&template_path, template_dir);
 	strbuf_complete(&template_path, '/');
@@ -200,7 +189,6 @@ static int create_default_files(const char *template_path,
 	int reinit;
 	int filemode;
 	struct strbuf err = STRBUF_INIT;
-	const char *init_template_dir = NULL;
 	const char *work_tree = get_git_work_tree();
 
 	/*
@@ -212,9 +200,7 @@ static int create_default_files(const char *template_path,
 	 * values (since we've just potentially changed what's available on
 	 * disk).
 	 */
-	git_config_get_pathname("init.templatedir", &init_template_dir);
-	copy_templates(template_path, init_template_dir);
-	free((char *)init_template_dir);
+	copy_templates(template_path);
 	git_config_clear();
 	reset_shared_repository();
 	git_config(git_default_config, NULL);

cache.h

@@ -656,6 +656,7 @@ int path_inside_repo(const char *prefix, const char *path);
 #define INIT_DB_QUIET 0x0001
 #define INIT_DB_EXIST_OK 0x0002
 
+const char *get_template_dir(const char *option_template);
 int init_db(const char *git_dir, const char *real_git_dir,
 	    const char *template_dir, int hash_algo,
 	    const char *initial_branch, unsigned int flags);

setup.c

@@ -6,6 +6,7 @@
 #include "chdir-notify.h"
 #include "promisor-remote.h"
 #include "quote.h"
+#include "exec-cmd.h"
 
 static int inside_git_dir = -1;
 static int inside_work_tree = -1;
@@ -1720,3 +1721,34 @@ int daemonize(void)
 	return 0;
 #endif
 }
+
+#ifndef DEFAULT_GIT_TEMPLATE_DIR
+#define DEFAULT_GIT_TEMPLATE_DIR "/usr/share/git-core/templates"
+#endif
+
+const char *get_template_dir(const char *option_template)
+{
+	const char *template_dir = option_template;
+
+	if (!template_dir)
+		template_dir = getenv(TEMPLATE_DIR_ENVIRONMENT);
+	if (!template_dir) {
+		static const char *init_template_dir;
+		static int initialized;
+
+		if (!initialized) {
+			git_config_get_pathname("init.templatedir",
+						&init_template_dir);
+			initialized = 1;
+		}
+		template_dir = init_template_dir;
+	}
+	if (!template_dir) {
+		static char *dir;
+
+		if (!dir)
+			dir = system_path(DEFAULT_GIT_TEMPLATE_DIR);
+		template_dir = dir;
+	}
+	return template_dir;
+}