mke2fs.c (zap_sector): Don't erase BSD disklabels on Alpha.

	(From Thorsten Kukuk <kukuk@suse.de>)

diff --git a/misc/ChangeLog b/misc/ChangeLog
index d84bf1f52db9633516404f4e0d22f86fada0a165..523f12b986f6b6570c28a3c46479329c4c04b13a 100644 (file)
--- a/misc/ChangeLog
+++ b/misc/ChangeLog
@@ -1,3 +1,8 @@
+2002-03-07  Theodore Tso  <tytso@mit.edu>
+
+       * mke2fs.c (zap_sector): Don't erase BSD disklabels on Alpha.
+               (From Thorsten Kukuk <kukuk@suse.de>)
+
 2002-03-04  Philipp Thomas  <pthomas@suse.de>
 
        * chattr.c (main), fsck.c (main), mke2fs.c (main), findsuper.c

diff --git a/misc/mke2fs.c b/misc/mke2fs.c
index f2fa3bd89438007c65f2ca76fc34169f82c626ae..671bd9e4e0fc927798edd545b34bf7d1d37ff79f 100644 (file)
--- a/misc/mke2fs.c
+++ b/misc/mke2fs.c
@@ -20,7 +20,7 @@
 #include <fcntl.h>
 #include <ctype.h>
 #include <time.h>
-#ifdef linux
+#ifdef __linux__
 #include <sys/utsname.h>
 #endif
 #ifdef HAVE_GETOPT_H
@@ -550,10 +550,16 @@ static void reserve_inodes(ext2_filsys fs)
        ext2fs_mark_ib_dirty(fs);
 }
 
+#ifdef __alpha__
+#define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
+#define BSD_LABEL_OFFSET        64
+#endif
+
 static void zap_sector(ext2_filsys fs, int sect, int nsect)
 {
        char *buf;
        int retval;
+       unsigned int *magic;
 
        buf = malloc(512*nsect);
        if (!buf) {
@@ -562,7 +568,20 @@ static void zap_sector(ext2_filsys fs, int sect, int nsect)
                exit(1);
        }
        memset(buf, 0, 512*nsect);
-       
+
+#ifdef __alpha__
+       /* Check for a BSD disklabel, and don't erase it if so */
+       retval = io_channel_read_blk(fs->io, 0, -512, buf);
+       if (retval)
+               fprintf(stderr, _("Warning: could not read block 0: %s\n"),
+                       error_message(retval));
+       else {
+               magic = (unsigned int *) (buf + BSD_LABEL_OFFSET);
+               if (*magic == BSD_DISKMAGIC)
+                       return;
+       }
+#endif
+
        io_channel_set_blksize(fs->io, 512);
        retval = io_channel_write_blk(fs->io, sect, -512*nsect, buf);
        io_channel_set_blksize(fs->io, fs->blocksize);
@@ -776,7 +795,7 @@ static void PRS(int argc, char *argv[])
        const char *    fs_type = 0;
        int             default_features = 1;
        blk_t           dev_size;
-#ifdef linux
+#ifdef __linux__
        struct          utsname ut;
 #endif
 
@@ -804,7 +823,7 @@ static void PRS(int argc, char *argv[])
        param.s_feature_incompat |= EXT2_FEATURE_INCOMPAT_FILETYPE;
        param.s_feature_ro_compat |= EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER;
                
-#ifdef linux
+#ifdef __linux__
        if (uname(&ut)) {
                perror("uname");
                exit(1);