init: handle empty "template" parameter

If a user passes "--template=", then our template parameter
is blank. Unfortunately, copy_templates() assumes it has at
least one character, and does all sorts of bad things like
reading from template[-1] and then proceeding to link all of
'/' into the .git directory.

This patch just checks for that condition in copy_templates
and aborts. As a side effect, this means that --template=
now has the meaning "don't copy any templates."

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-init-db.c b/builtin-init-db.c
index e23b8438c741651f48bbf529f89d0336cc718fed..c68a3b1e7409cb15879724d9acef1cecc97ab9fe 100644 (file)
--- a/builtin-init-db.c
+++ b/builtin-init-db.c
@@ -127,6 +127,8 @@ static void copy_templates(const char *template_dir)
                        template_dir = strbuf_detach(&d, NULL);
                }
        }
+       if (!template_dir[0])
+               return;
        strcpy(template_path, template_dir);
        template_len = strlen(template_path);
        if (template_path[template_len-1] != '/') {

diff --git a/t/t0001-init.sh b/t/t0001-init.sh
index d31887f9bf35a7fa9e31b1eb859a9cf21c918d6c..c0b781ae49af6cdc8a9bcc4a551310637366eb8f 100755 (executable)
--- a/t/t0001-init.sh
+++ b/t/t0001-init.sh
@@ -141,4 +141,30 @@ test_expect_success 'reinit' '
        test_cmp again/empty again/err2
 '
 
+test_expect_success 'init with --template' '
+       mkdir template-source &&
+       echo content >template-source/file &&
+       (
+               mkdir template-custom &&
+               cd template-custom &&
+               git init --template=../template-source
+       ) &&
+       test_cmp template-source/file template-custom/.git/file
+'
+
+test_expect_success 'init with --template (blank)' '
+       (
+               mkdir template-plain &&
+               cd template-plain &&
+               git init
+       ) &&
+       test -f template-plain/.git/info/exclude &&
+       (
+               mkdir template-blank &&
+               cd template-blank &&
+               git init --template=
+       ) &&
+       ! test -f template-blank/.git/info/exclude
+'
+
 test_done