Add our doscmd to the tree. This is a result of work from BSDI, and

a group of dos emulator developers.
Submitted by:	Jonathan Lemon <jlemon@americantv.com>
Obtained from:	BSDI

1 files changed, 98 insertions, 0 deletions

diff --git a/usr.bin/doscmd/doscmd_loader.c b/usr.bin/doscmd/doscmd_loader.c
new file mode 100644
index 0000000..7032bfb
--- /dev/null
+++ b/usr.bin/doscmd/doscmd_loader.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 1992, 1993, 1996
+ *	Berkeley Software Design, Inc.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Berkeley Software
+ *	Design, Inc.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	BSDI doscmd_loader.c,v 2.3 1996/04/08 19:32:33 bostic Exp
+ *
+ * $Id: doscmd_loader.c,v 1.2 1996/09/22 05:52:59 miff Exp $
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <a.out.h>
+
+/*
+ * reserve space in "low" memory for the interrupt vector table
+ */
+static const char filler[4096] = { 0, };
+
+#define _PATH_DOS_KERNEL_DIR	"/usr/libexec/"
+#define _PATH_DOS_KERNEL	"doscmd.kernel"
+
+int
+load_kernel(void)
+{
+    FILE *fp;
+    struct exec exec;
+    int start_address;
+
+    if ((fp = fopen(_PATH_DOS_KERNEL, "r")) == NULL &&
+	(fp = fopen("obj/" _PATH_DOS_KERNEL, "r")) == NULL &&
+	(fp = fopen(_PATH_DOS_KERNEL_DIR _PATH_DOS_KERNEL, "r")) == NULL &&
+	(fp = fopen(getenv("DOS_KERNEL"), "r")) == NULL)
+	err(1, "load_kernel");
+
+    if (fread(&exec, sizeof(exec), 1, fp) != 1 || N_GETMAGIC(exec) != OMAGIC)
+	errx(1, "bad kernel file format");
+
+    start_address = exec.a_entry & (~(getpagesize() - 1));
+    if (brk(start_address + exec.a_text + exec.a_data + exec.a_bss) < 0)
+	err(1, "load_kernel");
+    fread((char *)start_address, exec.a_text + exec.a_data, 1, fp);
+    bzero((char *)(start_address + exec.a_text + exec.a_data), exec.a_bss);
+    fclose(fp);
+    return(exec.a_entry);
+}
+
+void
+main(int argc, char **argv, char **environ)
+{
+    void (*entry_point)();
+#ifndef __FreeBSD__
+    int fd = open("/dev/mem", 0);
+#endif
+    setgid(getgid());
+    setuid(getuid());
+
+#ifndef __FreeBSD__
+    if (fd < 0)
+	err(1, "/dev/mem");
+#endif
+
+    entry_point = (void (*)()) load_kernel();
+
+#ifndef __FreeBSD__
+    if (read(fd, 0, 0x500 != 0x500))
+	err(1, "/dev/mem");
+
+    close(fd);
+#endif
+
+    (*entry_point)(argc, argv, environ);
+    errx(1, "return from doscmd kernel???");
+}