From b883356cf6cfb07ee36eaf14ea590e2318efc4ae Mon Sep 17 00:00:00 2001
From: Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>
Date: Wed, 14 Apr 2010 18:46:02 +0200
Subject: [PATCH] ntldr support. (based on information from nyu but no code
 from him)

---
 conf/i386-pc.rmk       |   6 ++
 loader/i386/pc/ntldr.c | 140 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 146 insertions(+)
 create mode 100644 loader/i386/pc/ntldr.c

diff --git a/conf/i386-pc.rmk b/conf/i386-pc.rmk
index 1b6221f4d..c138188ed 100644
--- a/conf/i386-pc.rmk
+++ b/conf/i386-pc.rmk
@@ -143,6 +143,12 @@ chain_mod_SOURCES = loader/i386/pc/chainloader.c
 chain_mod_CFLAGS = $(COMMON_CFLAGS)
 chain_mod_LDFLAGS = $(COMMON_LDFLAGS)
 
+# For ntldr.mod.
+pkglib_MODULES += ntldr.mod
+ntldr_mod_SOURCES = loader/i386/pc/ntldr.c
+ntldr_mod_CFLAGS = $(COMMON_CFLAGS)
+ntldr_mod_LDFLAGS = $(COMMON_LDFLAGS)
+
 pkglib_MODULES += linux16.mod
 linux16_mod_SOURCES = loader/i386/pc/linux.c
 linux16_mod_CFLAGS = $(COMMON_CFLAGS)
diff --git a/loader/i386/pc/ntldr.c b/loader/i386/pc/ntldr.c
new file mode 100644
index 000000000..9e461ff49
--- /dev/null
+++ b/loader/i386/pc/ntldr.c
@@ -0,0 +1,140 @@
+/* chainloader.c - boot another boot loader */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2002,2004,2007,2009,2010  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/loader.h>
+#include <grub/file.h>
+#include <grub/err.h>
+#include <grub/device.h>
+#include <grub/disk.h>
+#include <grub/misc.h>
+#include <grub/types.h>
+#include <grub/partition.h>
+#include <grub/dl.h>
+#include <grub/command.h>
+#include <grub/machine/biosnum.h>
+#include <grub/i18n.h>
+#include <grub/video.h>
+#include <grub/mm.h>
+#include <grub/cpu/relocator.h>
+
+static grub_dl_t my_mod;
+static struct grub_relocator *rel;
+
+#define GRUB_NTLDR_SEGMENT         0x2000
+
+static grub_err_t
+grub_ntldr_boot (void)
+{
+  struct grub_relocator16_state state = { 
+    .cs = GRUB_NTLDR_SEGMENT,
+    .ip = 0
+  };
+  grub_video_set_mode ("text", 0, 0);
+
+  return grub_relocator16_boot (rel, state);
+}
+
+static grub_err_t
+grub_ntldr_unload (void)
+{
+  grub_relocator_unload (rel);
+  rel = NULL;
+  grub_dl_unref (my_mod);
+  return GRUB_ERR_NONE;
+}
+
+static grub_err_t
+grub_cmd_ntldr (grub_command_t cmd __attribute__ ((unused)),
+		int argc, char *argv[])
+{
+  grub_file_t file = 0;
+  grub_err_t err;
+  void *bs, *ntldr;
+  grub_size_t ntldrsize;
+  grub_device_t dev;
+
+  if (argc == 0)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT, "no file specified");
+
+  grub_dl_ref (my_mod);
+
+  rel = grub_relocator_new ();
+  if (!rel)
+    goto fail;
+
+  file = grub_file_open (argv[0]);
+  if (! file)
+    goto fail;
+
+  err = grub_relocator_alloc_chunk_addr (rel, &bs, 0x7C00,
+					 GRUB_DISK_SECTOR_SIZE);
+  if (err)
+    goto fail;
+
+  dev = grub_device_open (0);
+
+  if (dev && dev->disk)
+    {
+      err = grub_disk_read (dev->disk, 0, 0, GRUB_DISK_SECTOR_SIZE, bs);
+      if (err)
+	{
+	  grub_device_close (dev);
+	  goto fail;
+	}
+    }
+
+  if (dev)
+    grub_device_close (dev);
+
+  ntldrsize = grub_file_size (file);
+  err = grub_relocator_alloc_chunk_addr (rel, &ntldr, GRUB_NTLDR_SEGMENT << 4,
+					 ntldrsize);
+  if (err)
+    goto fail;
+
+  if (grub_file_read (file, ntldr, ntldrsize)
+      != (grub_ssize_t) ntldrsize)
+    goto fail;
+ 
+  grub_loader_set (grub_ntldr_boot, grub_ntldr_unload, 1);
+  return GRUB_ERR_NONE;
+
+ fail:
+
+  if (file)
+    grub_file_close (file);
+
+  grub_ntldr_unload ();
+
+  return grub_errno;
+}
+
+static grub_command_t cmd;
+
+GRUB_MOD_INIT(ntldr)
+{
+  cmd = grub_register_command ("ntldr", grub_cmd_ntldr,
+			       0, N_("Load NTLDR or BootMGR."));
+  my_mod = mod;
+}
+
+GRUB_MOD_FINI(ntldr)
+{
+  grub_unregister_command (cmd);
+}