[PATCH v2] grub-core/commands/probe.c: Add bootable parameter

[Carlo Caione]

From: Carlo Caione <address@hidden>

Sometimes we are interested in checking whether an msdos partition has
the boot flag set. Introduce a new parameter to the probe command to
check this.

Signed-off-by: Carlo Caione <address@hidden>
---
 grub-core/commands/probe.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/grub-core/commands/probe.c b/grub-core/commands/probe.c
index cf2793e1d..f7a5563bf 100644
--- a/grub-core/commands/probe.c
+++ b/grub-core/commands/probe.c
@@ -31,6 +31,7 @@
 #include <grub/env.h>
 #include <grub/extcmd.h>
 #include <grub/i18n.h>
+#include <grub/msdos_partition.h>
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -45,6 +46,7 @@ static const struct grub_arg_option options[] =
     {"fs",             'f', 0, N_("Determine filesystem type."), 0, 0},
     {"fs-uuid",                'u', 0, N_("Determine filesystem UUID."), 0, 0},
     {"label",          'l', 0, N_("Determine filesystem label."), 0, 0},
+    {"bootable",       'b', 0, N_("Determine if bootable / active flag is 
set."), 0, 0},
     {0, 0, 0, 0, 0, 0}
   };
 
@@ -154,6 +156,30 @@ grub_cmd_probe (grub_extcmd_context_t ctxt, int argc, char 
**args)
       grub_device_close (dev);
       return GRUB_ERR_NONE;
     }
+  if (state[6].set)
+    {
+      const char *val = "none";
+      if (dev->disk && dev->disk->partition &&
+          grub_strcmp (dev->disk->partition->partmap->name, "msdos") == 0)
+        {
+          struct grub_msdos_partition_mbr mbr;
+          int index = dev->disk->partition->index;
+          grub_partition_t part = dev->disk->partition;
+          dev->disk->partition = part->parent;
+          if (!grub_disk_read (dev->disk, 0, 0, sizeof (mbr), &mbr))
+            {
+              if (mbr.entries[index].type != GRUB_PC_PARTITION_TYPE_GPT_DISK &&
+                  mbr.entries[index].flag & 0x80)
+                val = "bootable";
+            }
+        }
+      if (state[0].set)
+        grub_env_set (state[0].arg, val);
+      else
+        grub_printf ("%s", val);
+      grub_device_close (dev);
+      return GRUB_ERR_NONE;
+    }
   grub_device_close (dev);
   return grub_error (GRUB_ERR_BAD_ARGUMENT, "unrecognised target");
 }
-- 
2.14.1