patch-2.4.20 linux-2.4.20/arch/x86_64/boot/tools/build.c

• Lines: 190
• Date: Thu Nov 28 15:53:12 2002
• Orig file: linux-2.4.19/arch/x86_64/boot/tools/build.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.19/arch/x86_64/boot/tools/build.c linux-2.4.20/arch/x86_64/boot/tools/build.c
@@ -0,0 +1,189 @@
+/*
+ *  $Id: build.c,v 1.3 2001/06/26 15:14:50 pavel Exp $
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *  Copyright (C) 1997 Martin Mares
+ */
+
+/*
+ * This file builds a disk-image from three different files:
+ *
+ * - bootsect: exactly 512 bytes of 8086 machine code, loads the rest
+ * - setup: 8086 machine code, sets up system parm
+ * - system: 80386 code for actual system
+ *
+ * It does some checking that all files are of the correct type, and
+ * just writes the result to stdout, removing headers and padding to
+ * the right amount. It also writes some system data to stderr.
+ */
+
+/*
+ * Changes by tytso to allow root device specification
+ * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
+ * Cross compiling fixes by Gertjan van Wingerde, July 1996
+ * Rewritten by Martin Mares, April 1997
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <asm/boot.h>
+
+typedef unsigned char byte;
+typedef unsigned short word;
+typedef unsigned long u32;
+
+#define DEFAULT_MAJOR_ROOT 0
+#define DEFAULT_MINOR_ROOT 0
+
+/* Minimal number of setup sectors (see also bootsect.S) */
+#define SETUP_SECTS 4
+
+byte buf[1024];
+int fd;
+int is_big_kernel;
+
+void die(const char * str, ...)
+{
+	va_list args;
+	va_start(args, str);
+	vfprintf(stderr, str, args);
+	fputc('\n', stderr);
+	exit(1);
+}
+
+void file_open(const char *name)
+{
+	if ((fd = open(name, O_RDONLY, 0)) < 0)
+		die("Unable to open `%s': %m", name);
+}
+
+void usage(void)
+{
+	die("Usage: build [-b] bootsect setup system [rootdev] [> image]");
+}
+
+int main(int argc, char ** argv)
+{
+	unsigned int i, c, sz, setup_sectors;
+	u32 sys_size;
+	byte major_root, minor_root;
+	struct stat sb;
+
+	if (argc > 2 && !strcmp(argv[1], "-b"))
+	  {
+	    is_big_kernel = 1;
+	    argc--, argv++;
+	  }
+	if ((argc < 4) || (argc > 5))
+		usage();
+	if (argc > 4) {
+		if (!strcmp(argv[4], "CURRENT")) {
+			if (stat("/", &sb)) {
+				perror("/");
+				die("Couldn't stat /");
+			}
+			major_root = major(sb.st_dev);
+			minor_root = minor(sb.st_dev);
+		} else if (strcmp(argv[4], "FLOPPY")) {
+			if (stat(argv[4], &sb)) {
+				perror(argv[4]);
+				die("Couldn't stat root device.");
+			}
+			major_root = major(sb.st_rdev);
+			minor_root = minor(sb.st_rdev);
+		} else {
+			major_root = 0;
+			minor_root = 0;
+		}
+	} else {
+		major_root = DEFAULT_MAJOR_ROOT;
+		minor_root = DEFAULT_MINOR_ROOT;
+	}
+	fprintf(stderr, "Root device is (%d, %d)\n", major_root, minor_root);
+
+	file_open(argv[1]);
+	i = read(fd, buf, sizeof(buf));
+	fprintf(stderr,"Boot sector %d bytes.\n",i);
+	if (i != 512)
+		die("Boot block must be exactly 512 bytes");
+	if (buf[510] != 0x55 || buf[511] != 0xaa)
+		die("Boot block hasn't got boot flag (0xAA55)");
+	buf[508] = minor_root;
+	buf[509] = major_root;
+	if (write(1, buf, 512) != 512)
+		die("Write call failed");
+	close (fd);
+
+	file_open(argv[2]);				    /* Copy the setup code */
+	for (i=0 ; (c=read(fd, buf, sizeof(buf)))>0 ; i+=c )
+		if (write(1, buf, c) != c)
+			die("Write call failed");
+	if (c != 0)
+		die("read-error on `setup'");
+	close (fd);
+
+	setup_sectors = (i + 511) / 512;	/* Pad unused space with zeros */
+	/* for compatibility with ancient versions of LILO. */
+	if (setup_sectors < SETUP_SECTS)
+		setup_sectors = SETUP_SECTS;
+	fprintf(stderr, "Setup is %d bytes.\n", i);
+	memset(buf, 0, sizeof(buf));
+	while (i < setup_sectors * 512) {
+		c = setup_sectors * 512 - i;
+		if (c > sizeof(buf))
+			c = sizeof(buf);
+		if (write(1, buf, c) != c)
+			die("Write call failed");
+		i += c;
+	}
+
+	file_open(argv[3]);
+	if (fstat (fd, &sb))
+		die("Unable to stat `%s': %m", argv[3]);
+	sz = sb.st_size;
+	fprintf (stderr, "System is %d kB\n", sz/1024);
+	sys_size = (sz + 15) / 16;
+	/* 0x28000*16 = 2.5 MB, conservative estimate for the current maximum */
+	if (sys_size > (is_big_kernel ? 0x28000 : DEF_SYSSIZE))
+		die("System is too big. Try using %smodules.",
+			is_big_kernel ? "" : "bzImage or ");
+	if (sys_size > 0xefff)
+		fprintf(stderr,"warning: kernel is too big for standalone boot "
+		    "from floppy\n");
+	while (sz > 0) {
+		int l, n;
+
+		l = (sz > sizeof(buf)) ? sizeof(buf) : sz;
+		if ((n=read(fd, buf, l)) != l) {
+			if (n < 0)
+				die("Error reading %s: %m", argv[3]);
+			else
+				die("%s: Unexpected EOF", argv[3]);
+		}
+		if (write(1, buf, l) != l)
+			die("Write failed");
+		sz -= l;
+	}
+	close(fd);
+
+	if (lseek(1, 497, SEEK_SET) != 497)		    /* Write sizes to the bootsector */
+		die("Output: seek failed");
+	buf[0] = setup_sectors;
+	if (write(1, buf, 1) != 1)
+		die("Write of setup sector count failed");
+	if (lseek(1, 500, SEEK_SET) != 500)
+		die("Output: seek failed");
+	buf[0] = (sys_size & 0xff);
+	buf[1] = ((sys_size >> 8) & 0xff);
+	if (write(1, buf, 2) != 2)
+		die("Write of image length failed");
+
+	return 0;					    /* Everything is OK */
+}