Add support for forcing EFI installation to the removable media path

Add an extra option to grub-install "--force-extra-removable". On EFI
platforms, this will cause an extra copy of the grub-efi image to be
written to the appropriate removable media patch
/boot/efi/EFI/BOOT/BOOT$ARCH.EFI as well. This will help with broken
UEFI implementations where the firmware does not work when configured
with new boot paths.

Author: shankerwangmiao

util/grub-install.c

@@ -55,6 +55,7 @@
 
 static char *target;
 static int removable = 0;
+static int force_extra_removable = 0;
 static int recheck = 0;
 static int update_nvram = 1;
 static char *install_device = NULL;
@@ -109,7 +110,8 @@ enum
     OPTION_LABEL_FONT,
     OPTION_LABEL_COLOR,
     OPTION_LABEL_BGCOLOR,
-    OPTION_PRODUCT_VERSION
+    OPTION_PRODUCT_VERSION,
+    OPTION_FORCE_EXTRA_REMOVABLE,
   };
 
 static int fs_probe = 1;
@@ -212,6 +214,10 @@ argp_parser (int key, char *arg, struct argp_state *state)
       removable = 1;
       return 0;
 
+    case OPTION_FORCE_EXTRA_REMOVABLE:
+      force_extra_removable = 1;
+      return 0;
+
     case OPTION_ALLOW_FLOPPY:
       allow_floppy = 1;
       return 0;
@@ -302,6 +308,9 @@ static struct argp_option options[] = {
   {"label-color", OPTION_LABEL_COLOR, N_("COLOR"), 0, N_("use COLOR for label"), 2},
   {"label-bgcolor", OPTION_LABEL_BGCOLOR, N_("COLOR"), 0, N_("use COLOR for label background"), 2},
   {"product-version", OPTION_PRODUCT_VERSION, N_("STRING"), 0, N_("use STRING as product version"), 2},
+  {"force-extra-removable", OPTION_FORCE_EXTRA_REMOVABLE, 0, 0,
+   N_("force installation to the removable media path also. "
+      "This option is only available on EFI."), 2},
   {0, 0, 0, 0, 0, 0}
 };
 
@@ -843,12 +852,92 @@ try_open (const char *path)
 }
 #endif
 
+/* Helper routine for also_install_removable() below. Walk through the
+   specified dir, looking to see if there is a file/dir that matches
+   the search string exactly, but in a case-insensitive manner. If so,
+   return a copy of the exact file/dir that *does* exist. If not,
+   return NULL */
+static char *
+check_component_exists(const char *dir,
+		       const char *search)
+{
+  grub_util_fd_dir_t d;
+  grub_util_fd_dirent_t de;
+  char *found = NULL;
+
+  d = grub_util_fd_opendir (dir);
+  if (!d)
+    grub_util_error (_("cannot open directory `%s': %s"),
+		     dir, grub_util_fd_strerror ());
+
+  while ((de = grub_util_fd_readdir (d)))
+    {
+      if (strcasecmp (de->d_name, search) == 0)
+	{
+	  found = xstrdup (de->d_name);
+	  break;
+	}
+    }
+  grub_util_fd_closedir (d);
+  return found;
+}
+
+/* Some complex directory-handling stuff in here, to cope with
+ * case-insensitive FAT/VFAT filesystem semantics. Ugh. */
+static void
+also_install_removable(const char *src,
+		       const char *base_efidir,
+		       const char *efi_file)
+{
+  char *dst = NULL;
+  char *cur = NULL;
+  char *found = NULL;
+
+  /* We need to install in $base_efidir/EFI/BOOT/$efi_file, but we
+   * need to cope with case-insensitive stuff here. Build the path one
+   * component at a time, checking for existing matches each time. */
+
+  /* Look for "EFI" in base_efidir. Make it if it does not exist in
+   * some form. */
+  found = check_component_exists(base_efidir, "EFI");
+  if (found == NULL)
+    found = xstrdup("EFI");
+  dst = grub_util_path_concat (2, base_efidir, found);
+  cur = xstrdup (dst);
+  free (dst);
+  free (found);
+  grub_install_mkdir_p (cur);
+
+  /* Now BOOT */
+  found = check_component_exists(cur, "BOOT");
+  if (found == NULL)
+    found = xstrdup("BOOT");
+  dst = grub_util_path_concat (2, cur, found);
+  cur = xstrdup (dst);
+  free (dst);
+  free (found);
+  grub_install_mkdir_p (cur);
+
+  /* Now $efi_file */
+  found = check_component_exists(cur, efi_file);
+  if (found == NULL)
+    found = xstrdup(efi_file);
+  dst = grub_util_path_concat (2, cur, found);
+  cur = xstrdup (dst);
+  free (dst);
+  free (found);
+  grub_install_copy_file (src, cur, 1);
+
+  free (cur);
+}
+
 int
 main (int argc, char *argv[])
 {
   int is_efi = 0;
   const char *efi_distributor = NULL;
   const char *efi_file = NULL;
+  const char *removeable_efi_file = NULL;
   char **grub_devices;
   grub_fs_t grub_fs;
   grub_device_t grub_dev = NULL;
@@ -859,6 +948,7 @@ main (int argc, char *argv[])
   char *relative_grubdir;
   char **efidir_device_names = NULL;
   grub_device_t efidir_grub_dev = NULL;
+  char *base_efidir = NULL;
   char *efidir_grub_devname;
   int efidir_is_mac = 0;
   int is_prep = 0;
@@ -891,6 +981,9 @@ main (int argc, char *argv[])
       bootloader_id = xstrdup ("grub");
     }
 
+  if (removable && force_extra_removable)
+    grub_util_error (_("Invalid to use both --removable and --force_extra_removable"));
+
   if (!grub_install_source_directory)
     {
       if (!target)
@@ -1141,6 +1234,8 @@ main (int argc, char *argv[])
 	    grub_util_error (_("%s doesn't look like an EFI partition"), efidir);
 	}
 
+      base_efidir = xstrdup(efidir);
+
       /* The EFI specification requires that an EFI System Partition must
 	 contain an "EFI" subdirectory, and that OS loaders are stored in
 	 subdirectories below EFI.  Vendors are expected to pick names that do
@@ -1149,14 +1244,17 @@ main (int argc, char *argv[])
       */
       char *t;
       efi_distributor = bootloader_id;
-      if (removable)
+      if (removable || force_extra_removable)
 	{
 	  /* The specification makes stricter requirements of removable
 	     devices, in order that only one image can be automatically loaded
 	     from them.  The image must always reside under /EFI/BOOT, and it
 	     must have a specific file name depending on the architecture.
 	  */
-	  efi_distributor = "BOOT";
+	  if (removable)
+	    {
+	      efi_distributor = "BOOT";
+	    }
 	  switch (platform)
 	    {
 	    case GRUB_INSTALL_PLATFORM_I386_EFI:
@@ -1187,8 +1285,12 @@ main (int argc, char *argv[])
 	      grub_util_error ("%s", _("You've found a bug"));
 	      break;
 	    }
+	  if (force_extra_removable)
+	    {
+	      removeable_efi_file = efi_file;
+	    }
 	}
-      else
+      if (!removable)
 	{
 	  /* It is convenient for each architecture to have a different
 	     efi_file, so that different versions can be installed in parallel.
@@ -1989,6 +2091,9 @@ main (int argc, char *argv[])
 	char *dst = grub_util_path_concat (2, efidir, efi_file);
 	grub_install_copy_file (imgfile, dst, 1);
 
+	if (force_extra_removable)
+	    also_install_removable(imgfile, base_efidir, removeable_efi_file);
+
 	grub_set_install_backup_ponr ();
 
 	free (dst);