[Libguestfs] [PATCH] NTFS: Invoke mkfs ntfs with -Q option.

[Richard W.M. Jones]

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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>From 4ccaf11cb04d69763e390d4df5d6eecf9270e2ca Mon Sep 17 00:00:00 2001
From: Richard Jones <rjones at redhat.com>
Date: Sun, 8 Nov 2009 11:57:02 +0000
Subject: [PATCH] NTFS: Invoke mkfs ntfs with -Q option.

By default mkfs.ntfs writes zeroes and does bad block detection
over the whole disk.  This is slow and unnecessary in the virtual
case.  Pass -Q option to avoid this.
---
 daemon/mkfs.c |   58 ++++++++++++++++++++++++++++++++++++++++----------------
 1 files changed, 41 insertions(+), 17 deletions(-)

diff --git a/daemon/mkfs.c b/daemon/mkfs.c
index faeeaeb..84b7298 100644
--- a/daemon/mkfs.c
+++ b/daemon/mkfs.c
@@ -29,15 +29,40 @@
 #include "daemon.h"
 #include "actions.h"
 
-int
-do_mkfs (const char *fstype, const char *device)
+#define MAX_ARGS 16
+
+static int
+mkfs (const char *fstype, const char *device,
+      const char **extra, size_t nr_extra)
 {
-  char *err;
+  const char *argv[MAX_ARGS];
+  size_t i = 0, j;
   int r;
+  char *err;
+
+  argv[i++] = "/sbin/mkfs";
+  argv[i++] = "-t";
+  argv[i++] = fstype;
+
+  /* mkfs.ntfs requires the -Q argument otherwise it writes zeroes
+   * to every block and does bad block detection, neither of which
+   * are useful behaviour for virtual devices.
+   */
+  if (strcmp (fstype, "ntfs") == 0)
+    argv[i++] = "-Q";
 
-  r = command (NULL, &err, "/sbin/mkfs", "-t", fstype, device, NULL);
+  for (j = 0; j < nr_extra; ++j)
+    argv[i++] = extra[j];
+
+  argv[i++] = device;
+  argv[i++] = NULL;
+
+  if (i > MAX_ARGS)
+    abort ();
+
+  r = commandv (NULL, &err, argv);
   if (r == -1) {
-    reply_with_error ("mkfs: %s", err);
+    reply_with_error ("mkfs: %s: %s: %s", fstype, device, err);
     free (err);
     return -1;
   }
@@ -47,22 +72,21 @@ do_mkfs (const char *fstype, const char *device)
 }
 
 int
-do_mkfs_b (const char *fstype, int blocksize, const char *device)
+do_mkfs (const char *fstype, const char *device)
 {
-  char *err;
-  int r;
+  return mkfs (fstype, device, NULL, 0);
+}
 
+int
+do_mkfs_b (const char *fstype, int blocksize, const char *device)
+{
+  const char *extra[2];
   char blocksize_s[32];
+
   snprintf (blocksize_s, sizeof blocksize_s, "%d", blocksize);
 
-  r = command (NULL, &err,
-               "/sbin/mkfs", "-t", fstype, "-b", blocksize_s, device, NULL);
-  if (r == -1) {
-    reply_with_error ("mkfs_b: %s", err);
-    free (err);
-    return -1;
-  }
+  extra[0] = "-b";
+  extra[1] = blocksize_s;
 
-  free (err);
-  return 0;
+  return mkfs (fstype, device, extra, 2);
 }
-- 
1.6.5.rc2