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-rw-r--r--com32/mboot/mb_header.h90
1 files changed, 90 insertions, 0 deletions
diff --git a/com32/mboot/mb_header.h b/com32/mboot/mb_header.h
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+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2000 Free Software Foundation, Inc.
+ *
+ * This program 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/*
+ * MultiBoot Header description
+ */
+
+struct multiboot_header
+{
+ /* Must be MULTIBOOT_MAGIC - see below. */
+ unsigned magic;
+
+ /* Feature flags - see below. */
+ unsigned flags;
+
+ /*
+ * Checksum
+ *
+ * The above fields plus this one must equal 0 mod 2^32.
+ */
+ unsigned checksum;
+
+ /* These are only valid if MULTIBOOT_AOUT_KLUDGE is set. */
+ unsigned header_addr;
+ unsigned load_addr;
+ unsigned load_end_addr;
+ unsigned bss_end_addr;
+ unsigned entry_addr;
+
+ /* These are only valid if MULTIBOOT_VIDEO_MODE is set. */
+ unsigned mode_type;
+ unsigned width;
+ unsigned height;
+ unsigned depth;
+};
+
+/*
+ * The entire multiboot_header must be contained
+ * within the first MULTIBOOT_SEARCH bytes of the kernel image.
+ */
+#define MULTIBOOT_SEARCH 8192
+#define MULTIBOOT_FOUND(addr, len) \
+ (! ((addr) & 0x3) \
+ && (len) >= 12 \
+ && *((int *) (addr)) == MULTIBOOT_MAGIC \
+ && ! (*((unsigned *) (addr)) + *((unsigned *) (addr + 4)) \
+ + *((unsigned *) (addr + 8))) \
+ && (! (MULTIBOOT_AOUT_KLUDGE & *((int *) (addr + 4))) || (len) >= 32) \
+ && (! (MULTIBOOT_VIDEO_MODE & *((int *) (addr + 4))) || (len) >= 48))
+
+/* Magic value identifying the multiboot_header. */
+#define MULTIBOOT_MAGIC 0x1BADB002
+
+/*
+ * Features flags for 'flags'.
+ * If a boot loader sees a flag in MULTIBOOT_MUSTKNOW set
+ * and it doesn't understand it, it must fail.
+ */
+#define MULTIBOOT_MUSTKNOW 0x0000FFFF
+
+/* currently unsupported flags... this is a kind of version number. */
+#define MULTIBOOT_UNSUPPORTED 0x0000FFF8
+
+/* Align all boot modules on i386 page (4KB) boundaries. */
+#define MULTIBOOT_PAGE_ALIGN 0x00000001
+
+/* Must pass memory information to OS. */
+#define MULTIBOOT_MEMORY_INFO 0x00000002
+
+/* Must pass video information to OS. */
+#define MULTIBOOT_VIDEO_MODE 0x00000004
+
+/* This flag indicates the use of the address fields in the header. */
+#define MULTIBOOT_AOUT_KLUDGE 0x00010000