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#ident "$Id$"
/* ----------------------------------------------------------------------- *
*
* Copyright 2002 H. Peter Anvin - All Rights Reserved
*
* 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, Inc., 53 Temple Place Ste 330,
* Bostom MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* hello2.c
*
* Simple COM32 image
*
* This version shows how to use the bounce buffer for data transfer
* to the BIOS or COMBOOT system calls.
*/
#include <com32.h>
#define NULL ((void *)0)
static inline void memset(void *buf, int ch, unsigned int len)
{
asm volatile("cld; rep; stosb"
: "+D" (buf), "+c" (len) : "a" (ch) : "memory");
}
static inline void memcpy(void *dst, const void *src, unsigned int len)
{
asm volatile("cld; rep; movsb"
: "+D" (dst), "+S" (src), "+c" (len) : : "memory");
}
int __start(void)
{
const char msg[] = "Hello, World!\r\n";
com32sys_t inreg, outreg;
const char *p;
memset(&inreg, 0, sizeof inreg);
/* Bounce buffer is at least 64K in size */
memcpy(__com32.cs_bounce, msg, sizeof msg);
inreg.eax.w[0] = 0x0002; /* Write string */
inreg.ebx.w[0] = OFFS(__com32.cs_bounce);
inreg.es = SEG(__com32.cs_bounce);
__com32.cs_syscall(0x22, &inreg, NULL);
return 0;
}
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