fdisk: cleanup full disk detection code

The full disk (e.g. /dev/hda) detection code is duplicated on two places and
the code doesn't work correctly with devices which don't support HDIO_GETGEO.

Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/fdisk/disksize.c b/fdisk/disksize.c
index 28b8df0a..cc00e933 100644
--- a/fdisk/disksize.c
+++ b/fdisk/disksize.c
@@ -1,3 +1,9 @@
+#include <stdio.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
 #include <errno.h>
 #include "common.h"
 
@@ -19,3 +25,30 @@ int disksize(int fd, unsigned long long *sectors) {
 		*sectors = (b >> 9);
 	return 0;
 }
+
+int
+is_probably_full_disk(char *name) {
+#ifdef HDIO_GETGEO
+	struct hd_geometry geometry;
+	int fd, i = 0;
+
+	fd = open(name, O_RDONLY);
+	if (fd >= 0) {
+		i = ioctl(fd, HDIO_GETGEO, &geometry);
+		close(fd);
+	}
+	if (i==0)
+		return (fd >= 0 && geometry.start == 0);
+#endif
+	/*
+	 * The "silly heuristic" is still sexy for us, because
+	 * for example Xen doesn't implement HDIO_GETGEO for virtual
+	 * block devices (/dev/xvda).
+	 *
+	 * -- kzak@redhat.com (23-Feb-2006)
+	 */
+	while (*name)
+		name++;
+	return !isdigit(name[-1]);
+}
+