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-rw-r--r--libblkid/wholedisk.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/libblkid/wholedisk.c b/libblkid/wholedisk.c
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+++ b/libblkid/wholedisk.c
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+/*
+ * No copyright is claimed. This code is in the public domain; do with
+ * it what you wish.
+ *
+ * Written by Karel Zak <kzak@redhat.com>
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+
+#include "blkdev.h"
+#include "wholedisk.h"
+
+int is_whole_disk_fd(int fd, const char *name)
+{
+#ifdef HDIO_GETGEO
+ if (fd != -1) {
+ struct hd_geometry geometry;
+ int i = ioctl(fd, HDIO_GETGEO, &geometry);
+ if (i == 0)
+ return 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]);
+}
+
+int is_whole_disk(const char *name)
+{
+ int fd = -1, res = 0;
+#ifdef HDIO_GETGEO
+ fd = open(name, O_RDONLY);
+ if (fd != -1)
+#endif
+ res = is_whole_disk_fd(fd, name);
+
+ if (fd != -1)
+ close(fd);
+ return res;
+}
+
+#ifdef TEST_PROGRAM
+int main(int argc, char **argv)
+{
+ if (argc < 2) {
+ fprintf(stderr, "usage: %s <device>\n", argv[0]);
+ exit(EXIT_FAILURE);
+ }
+
+ printf("%s: is%s whole disk\n", argv[1],
+ is_whole_disk(argv[1]) ? "" : " NOT");
+ exit(EXIT_SUCCESS);
+}
+#endif