Files
FireBee_SVN/emusd.c
Markus Fröschle 1e3221a84e initial import
2013-05-01 20:10:04 +00:00

121 lines
2.0 KiB
C

/*
* emusd.c
*
* The driver actually resides within BaS_gcc. All we need to do within the AUTO-folder program is to find the driver
* entry point and put its address into the XHDI cookie
*
* Created on: 01.05.2013
* Author: mfro
*/
#include <stdint.h>
#include <stddef.h>
#include <stdio.h>
#include <osbind.h>
#define XHDIMAGIC 0x27011992L
typedef uint32_t (*cookie_fun)(uint16_t opcode,...);
static cookie_fun old_vector = NULL;
static long cookieptr (void)
{
return *((long *)0x5a0L);
}
static int getcookie(uint32_t cookie, uint32_t *p_value)
{
long *cookiejar = (long *) Supexec (cookieptr);
if (!cookiejar) return 0;
do
{
if (cookiejar[0] == cookie)
{
if (p_value) *p_value = cookiejar[1];
return 1;
}
else
cookiejar = &(cookiejar[2]);
} while (cookiejar[-2]);
return 0;
}
static void setcookie(uint32_t cookie, uint32_t value)
{
long *cookiejar = (long *) Supexec(cookieptr);
do
{
if (cookiejar[0] == cookie)
{
cookiejar[1] = value;
return;
}
else
cookiejar = &(cookiejar[2]);
} while (cookiejar[-2]);
}
static cookie_fun get_fun_ptr(void)
{
static cookie_fun XHDI = NULL;
static int have_it = 0;
if (!have_it)
{
uint32_t *magic_test;
getcookie ('XHDI', (uint32_t *) &XHDI);
have_it = 1;
/* check magic */
magic_test = (uint32_t *)XHDI;
if (magic_test && (magic_test[-1] != XHDIMAGIC))
XHDI = NULL;
}
return XHDI;
}
__extension__ cookie_fun bas_sd_vector(cookie_fun old_vector)
{
register long retvalue __asm__("d0");
__asm__ __volatile(
"move.l %1,-(sp)\n\t"
"trap #0\n\t"
"addq.l #4,sp\n\t"
: "=r"(retvalue)
: "g"(old_vector)
:
);
retvalue;
}
int main(int argc, char *argv[])
{
uint32_t value;
cookie_fun bas_vector;
if (getcookie('XHDI', &value))
{
if ((old_vector = get_fun_ptr()))
{
printf("old XHDI vector (%p) found and saved\r\n", old_vector);
}
}
bas_vector = bas_sd_vector(old_vector);
printf("got vector from BaS: %p\r\n", bas_vector);
setcookie('XHDI', (uint32_t) bas_vector);
printf("vector to BaS driver set\r\n");
return 0;
}