zcat: fix "zcat FILE" trying to do detection twice

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/archival/bbunzip.c b/archival/bbunzip.c
index 54dc2f5..d59c655 100644 (file)
--- a/archival/bbunzip.c
+++ b/archival/bbunzip.c
@@ -66,12 +66,17 @@ int FAST_FUNC bbunpack(char **argv,
                                if (open_to_or_warn(STDIN_FILENO, filename, O_RDONLY, 0))
                                        goto err;
                        } else {
-                               /* "clever zcat" */
+                               /* "clever zcat" with FILE */
                                int fd = open_zipped(filename);
                                if (fd < 0)
                                        goto err_name;
                                xmove_fd(fd, STDIN_FILENO);
                        }
+               } else
+               if (option_mask32 & SEAMLESS_MAGIC) {
+                       /* "clever zcat" on stdin */
+                       if (setup_unzip_on_fd(STDIN_FILENO, /*fail_if_not_detected*/ 0))
+                               goto err;
                }
 
                /* Special cases: test, stdout */
@@ -115,15 +120,9 @@ int FAST_FUNC bbunpack(char **argv,
                        if (status < 0)
                                exitcode = 1;
                } else {
-                       /* "clever zcat" */
-                       if (!filename) {
-                               if (setup_unzip_on_fd(STDIN_FILENO, /*fail_if_not_detected*/ 0))
-                                       goto err;
-                       }
-                       if (bb_copyfd_eof(STDIN_FILENO, STDOUT_FILENO) < 0) {
+                       if (bb_copyfd_eof(STDIN_FILENO, STDOUT_FILENO) < 0)
                                /* Disk full, tty closed, etc. No point in continuing */
                                xfunc_die();
-                       }
                }
 
                if (!(option_mask32 & OPT_STDOUT))