BusyBox has no business hard coding the number of major and minor bits for a

dev_t.  This is especially important now that the user space concept of a dev_t
and the kernel concept of a dev_t are divergant.  The only bit of user space
allowed to know the number of major and minor bits is include/sys/sysmacros.h
(i.e. part of libc).  When used with a current C library and a 2.6.x kernel,
this fix should allow BusyBox to support wide device major/minor numbers.
 -Erik

1 files changed, 5 insertions, 9 deletions

diff --git a/archival/tar.c b/archival/tar.c
index 2de6454e7..689dd1424 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -49,6 +49,7 @@
 #include <signal.h>
 #include <sys/wait.h>
 #include <sys/socket.h>
+#include <sys/sysmacros.h>     /* major() and minor() */
 #include "unarchive.h"
 #include "busybox.h"
 
@@ -58,11 +59,6 @@
 # define TAR_MAGIC          "ustar"     /* ustar and a null */
 # define TAR_VERSION        "  "        /* Be compatable with GNU tar format */
 
-# ifndef MAJOR
-#  define MAJOR(dev) (((dev)>>8)&0xff)
-#  define MINOR(dev) ((dev)&0xff)
-# endif
-
 static const int TAR_BLOCK_SIZE = 512;
 static const int TAR_MAGIC_LEN = 6;
 static const int TAR_VERSION_LEN = 2;
@@ -262,15 +258,15 @@ static inline int writeTarHeader(struct TarBallInfo *tbInfo,
         } else if (S_ISCHR(statbuf->st_mode)) {
                 header.typeflag = CHRTYPE;
                 putOctal(header.devmajor, sizeof(header.devmajor),
-                                 MAJOR(statbuf->st_rdev));
+                                 major(statbuf->st_rdev));
                 putOctal(header.devminor, sizeof(header.devminor),
-                                 MINOR(statbuf->st_rdev));
+                                 minor(statbuf->st_rdev));
         } else if (S_ISBLK(statbuf->st_mode)) {
                 header.typeflag = BLKTYPE;
                 putOctal(header.devmajor, sizeof(header.devmajor),
-                                 MAJOR(statbuf->st_rdev));
+                                 major(statbuf->st_rdev));
                 putOctal(header.devminor, sizeof(header.devminor),
-                                 MINOR(statbuf->st_rdev));
+                                 minor(statbuf->st_rdev));
         } else if (S_ISFIFO(statbuf->st_mode)) {
                 header.typeflag = FIFOTYPE;
         } else if (S_ISREG(statbuf->st_mode)) {