[syslinux] Can not use read file SYSLINUX API call

[Phung Chi Kien]

Hi Peter Anvin
I tried to use open file and read file SYSLINUX API. But it always make my
PC104 freeze. My snip code :


================================================
int __start(void)
{
int ax,cx,dx,es,si,di,t;
com32sys_t  inreg,outreg;

memset(&inreg, 0, sizeof inreg);
memset(&outreg, 0, sizeof outreg);
strcopy(__com32.cs_bounce, "test.txt");
inreg.eax.w[0] = 0x0006;  // Open file
inreg.esi.w[0] = OFFS(__com32.cs_bounce);
inreg.es = SEG(__com32.cs_bounce);
__com32.cs_intcall(0x22, &inreg, &outreg);

si = outreg.esi.w[0];
cx = outreg.ecx.w[0];
ax = outreg.eax.w[0];
if ((ax % cx) == 0)
t = ax / cx;
else
t = (ax / cx) + 1;

memset(&inreg, 0, sizeof inreg);
inreg.esi.w[0] = si;
inreg.ecx.w[0] = t;
inreg.eax.w[0] = 0x0007;  // Read file
inreg.ebx.w[0] = OFFS(__com32.cs_bounce);
inreg.es = SEG(__com32.cs_bounce);
__com32.cs_intcall(0x22, &inreg, NULL);

memset(&inreg, 0, sizeof inreg);
inreg.eax.w[0] = 0x0002;  //  Write content of file to console
inreg.ebx.w[0] = OFFS(__com32.cs_bounce);
inreg.es = SEG(__com32.cs_bounce);
__com32.cs_intcall(0x22, &inreg, NULL);

memset(&inreg, 0, sizeof inreg);
inreg.eax.w[0] = 0x000C;  //  Clean up
inreg.edx.w[0] = 0x0000;
__com32.cs_intcall(0x22, &inreg, NULL);

..........................

=========================================
Please tell me where is the error in my codes.
Thanks very much

Phung Chi Kien
Automation Institute
Hanoi
Vietnam