Introduce usagef() that takes a printf-style format

diff --git a/builtin-tar-tree.c b/builtin-tar-tree.c
index 8b3a35e12da2cca8b632d4139bc2c5ba2409d322..3f1e7012db1af7d3695e6517956721a313229d65 100644 (file)
--- a/builtin-tar-tree.c
+++ b/builtin-tar-tree.c
@@ -11,6 +11,9 @@ static const char tar_tree_usage[] =
 "git tar-tree [--remote=<repo>] <tree-ish> [basedir]\n"
 "*** Note that this command is now deprecated; use \"git archive\" instead.";
 
+static const char builtin_get_tar_commit_id_usage[] =
+"git get-tar-commit-id < <tarfile>";
+
 int cmd_tar_tree(int argc, const char **argv, const char *prefix)
 {
        /*
@@ -81,6 +84,9 @@ int cmd_get_tar_commit_id(int argc, const char **argv, const char *prefix)
        char *content = buffer + RECORDSIZE;
        ssize_t n;
 
+       if (argc != 1)
+               usage(builtin_get_tar_commit_id_usage);
+
        n = read_in_full(0, buffer, HEADERSIZE);
        if (n < HEADERSIZE)
                die("git get-tar-commit-id: read error");