[PATCH] Add option to grub-probe to accept system devices as arguments

[Fabian Greffrath]

The following patch adds to grub-probe the ability to accept system devices as
arguments and e.g. convert between system devices and GRUB drives.

This patch is improved over the one from my previous posting and has some minor
issues fixed. Please use this version instead. It is all my work.




2008-02-11  Fabian Greffrath  <address@hidden>

        * util/grub-probe.c: Add new parameter '-d, --device'. If this is set,
        grub-probe expects the given argument to be a block device. All of the
        '--target' parameters work with this option as well. If the '--device'
        parameter is not set, grub-probe will work as before.

        * util/getroot.c (grub_util_check_block_device): New public function
        that returns the given argument if it is a block device and returns
        NULL else.

        * util/getroot.h (grub_util_check_block_device): Export function.

diff -Naru grub2-1.96+20080203~/include/grub/util/getroot.h 
grub2-1.96+20080203/include/grub/util/getroot.h
--- grub2-1.96+20080203~/include/grub/util/getroot.h    2008-01-12 
16:11:56.000000000 +0100
+++ grub2-1.96+20080203/include/grub/util/getroot.h     2008-02-08 
12:49:52.000000000 +0100
@@ -29,5 +29,6 @@
 char *grub_get_prefix (const char *dir);
 int grub_util_get_dev_abstraction (const char *os_dev);
 char *grub_util_get_grub_dev (const char *os_dev);
+char *grub_util_check_block_device (const char *blk_dev);
 
 #endif /* ! GRUB_UTIL_GETROOT_HEADER */
diff -Naru grub2-1.96+20080203~/util/getroot.c 
grub2-1.96+20080203/util/getroot.c
--- grub2-1.96+20080203~/util/getroot.c 2008-01-12 16:11:56.000000000 +0100
+++ grub2-1.96+20080203/util/getroot.c  2008-02-08 12:49:52.000000000 +0100
@@ -327,3 +327,17 @@
 
   return grub_dev;
 }
+
+char *
+grub_util_check_block_device (const char *blk_dev)
+{
+  struct stat st;
+
+  if (stat (blk_dev, &st) < 0)
+    grub_util_error ("Cannot stat `%s'", blk_dev);
+
+  if (S_ISBLK (st.st_mode))
+    return strdup (blk_dev);
+  else
+    return 0;
+}
diff -Naru grub2-1.96+20080203~/util/grub-probe.c 
grub2-1.96+20080203/util/grub-probe.c
--- grub2-1.96+20080203~/util/grub-probe.c      2008-01-25 23:33:57.000000000 
+0100
+++ grub2-1.96+20080203/util/grub-probe.c       2008-02-08 12:50:13.000000000 
+0100
@@ -50,6 +50,7 @@
 };
 
 int print = PRINT_FS;
+static unsigned int argument_is_device = 0;
 
 void
 grub_putchar (int c)
@@ -84,9 +85,18 @@
   int abstraction_type;
   grub_device_t dev = NULL;
   
-  device_name = grub_guess_root_device (path);
+  if (argument_is_device)
+    device_name = grub_util_check_block_device (path);
+  else
+    device_name = grub_guess_root_device (path);
+
   if (! device_name)
-    grub_util_error ("cannot find a device for %s.\n", path);
+    {
+      if (argument_is_device)
+        grub_util_error ("%s is not a block device.\n", path);
+      else
+        grub_util_error ("cannot find a device for %s.\n", path);
+    }
 
   if (print == PRINT_DEVICE)
     {
@@ -201,6 +211,7 @@
 
 static struct option options[] =
   {
+    {"device", no_argument, 0, 'd'},
     {"device-map", required_argument, 0, 'm'},
     {"target", required_argument, 0, 't'},
     {"help", no_argument, 0, 'h'},
@@ -217,10 +228,11 @@
             "Try ``grub-probe --help'' for more information.\n");
   else
     printf ("\
-Usage: grub-probe [OPTION]... PATH\n\
+Usage: grub-probe [OPTION]... [PATH|DEVICE]\n\
 \n\
-Probe device information for a given path.\n\
+Probe device information for a given path or device.\n\
 \n\
+  -d, --device              given argument is a system device, not a path\n\
   -m, --device-map=FILE     use FILE as the device map [default=%s]\n\
   -t, --target=(fs|drive|device|partmap|abstraction)\n\
                             print filesystem module, GRUB drive, system 
device, partition map module or abstraction module [default=fs]\n\
@@ -246,13 +258,17 @@
   /* Check for options.  */
   while (1)
     {
-      int c = getopt_long (argc, argv, "m:t:hVv", options, 0);
+      int c = getopt_long (argc, argv, "dm:t:hVv", options, 0);
       
       if (c == -1)
        break;
       else
        switch (c)
          {
+         case 'd':
+           argument_is_device = 1;
+           break;
+
          case 'm':
            if (dev_map)
              free (dev_map);