1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
/* ----------------------------------------------------------------------- *
*
* 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,
* Boston 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 void strcpy(char *dst, const char *src)
{
while ( *src )
*dst++ = *src++;
*dst = '\0';
}
static void writemsg(const char *msg)
{
com32sys_t inreg;
memset(&inreg, 0, sizeof inreg);
strcpy(__com32.cs_bounce, msg);
inreg.eax.w[0] = 0x0002; /* Write string */
inreg.ebx.w[0] = OFFS(__com32.cs_bounce);
inreg.es = SEG(__com32.cs_bounce);
__com32.cs_intcall(0x22, &inreg, NULL);
};
int __start(void)
{
writemsg("Hello, World!\r\n"
"cmdline = ");
writemsg(__com32.cs_cmdline);
writemsg("\r\n");
return 0;
}
|
