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Ignore whitespace Rev 40 → Rev 41

/shark/trunk/oslib/examples/syscalls.c
0,0 → 1,203
/* Project: OSLib
* Description: The OS Construction Kit
* Date: 1.6.2000
* Idea by: Luca Abeni & Gerardo Lamastra
*
* OSLib is an SO project aimed at developing a common, easy-to-use
* low-level infrastructure for developing OS kernels and Embedded
* Applications; it partially derives from the HARTIK project but it
* currently is independently developed.
*
* OSLib is distributed under GPL License, and some of its code has
* been derived from the Linux kernel source; also some important
* ideas come from studying the DJGPP go32 extender.
*
* We acknowledge the Linux Community, Free Software Foundation,
* D.J. Delorie and all the other developers who believe in the
* freedom of software and ideas.
*
* For legalese, check out the included GPL license.
*/
 
/* Address Spaces test file */
 
#include <ll/i386/stdlib.h>
#include <ll/i386/error.h>
#include <ll/i386/mem.h>
#include <ll/i386/hw-arch.h>
#include <ll/i386/farptr.h>
#include <ll/sys/ll/ll-func.h>
#include <ll/sys/ll/aspace.h>
#include <ll/sys/ll/event.h>
#include <ll/string.h>
 
#define USE_NEW_HANDLERS
#define T 1000
#define WAIT() for (w = 0; w < 0x5FFFFF; w++)
 
extern DWORD GDT_base;
extern void int0x31(void);
 
#ifndef USE_NEW_HANDLERS
struct regs {
DWORD flags;
DWORD egs;
DWORD efs;
DWORD ees;
DWORD eds;
DWORD edi;
DWORD esi;
DWORD ebp;
DWORD esp;
DWORD ebx;
DWORD edx;
DWORD ecx;
DWORD eax;
};
#endif
 
BYTE space[2048];
WORD th1, th2, thm;
 
char outstring[] = "Hi there!!!\n";
 
#ifdef USE_NEW_HANDLERS
void chandler(DWORD intnum, struct registers r)
#else
void chandler(struct regs r, DWORD intnum)
#endif
{
message("[System Call] EAX = 0x%lx EBX = 0x%lx ECX = 0x%lx...\n",
r.eax, r.ebx, r.ecx);
 
if (r.eax == 1) {
message("Exit!!!\n");
ll_context_load(thm);
}
 
if (r.eax == 2) {
char string[20];
DWORD p;
unsigned int size;
 
p = GDT_read(r.eds, NULL, NULL, NULL);
p += r.ebx;
size = r.ecx;
if (size > 20) {
size = 20;
}
#if 0
message("Buffer @0x%lx, len %u\n", p, size);
l1_end();
sti();
l1_exit(0);
#endif
 
memcpy(string, (void *)p, size);
string[19] = 0;
message("Write...\n");
message("%s", string);
return;
}
 
message("Unsupported System Call!!!\n");
}
 
 
/* For now, this is not called */
void killer(void)
{
cli();
message("Killer!!!\n");
ll_context_load(thm);
}
 
/*
And this is the thread that runs in the new AS... It cannot call
any function (it is alone in its AS), so it simply plots a star
on the screen and loops waiting for an event that switches to the
main thread.
*/
void nullfun(void *p)
{
/* Some asm to write on the screen (we cannot use libc... it is not
linked in this AS */
__asm__ __volatile__ ("movl $2, %eax");
__asm__ __volatile__ ("movl $1000, %ebx");
__asm__ __volatile__ ("movl $16, %ecx");
__asm__ __volatile__ ("int $0x31");
__asm__ __volatile__ ("movl $1, %eax");
__asm__ __volatile__ ("int $0x31");
 
/* should not arrive here... */
for(;;);
halt();
}
 
int main (int argc, char *argv[])
{
DWORD sp1, sp2;
void *res;
AS as, ds;
int ok;
sp1 = get_SP();
cli();
res = ll_init();
 
if (res == NULL) {
message("Error in LowLevel initialization code...\n");
sti();
l1_exit(-1);
}
message("LowLevel started...\n");
#ifdef USE_NEW_HANDLERS
l1_int_bind(0x31, chandler);
#else
IDT_place(0x31, int0x31);
#endif
as_init();
 
message("Creating an Address Space\n");
as = as_create();
message("Created: ID = %d %x\n", as, as);
message("Binding array @ 0x%lx\n", (DWORD)space);
ok = as_bind(as, (DWORD)space, 0, sizeof(space));
 
if (ok < 0) {
message("Error in as_bind!!!\n");
} else {
message("Bound\n");
}
 
ds = get_DS();
/* Let's create the image of the process...
* 0 --> 1000 : text
* 1000 --> 1000 + strlen(outstring) : initialized data
* ? <-- 2048 : stack
*/
fmemcpy(as, 0, ds, (DWORD)nullfun, 1000);
fmemcpy(as, 1000, ds, (DWORD)outstring, strlen(outstring));
/* Create a thread (in our AS) and a task (in a different AS) */
th1 = ll_context_create(0, (void *)2048, NULL,killer, 0);
ll_context_setspace(th1, as);
/* Save our context, in order to permit to switch back to main */
thm = ll_context_save();
message("I am thread %x\n", thm);
message("Thread 1 created\n");
message("Switching to it...\n");
ll_context_load(th1);
message("Back to Main\n");
 
cli();
ll_end();
sp2 = get_SP();
message("End reached!\n");
message("Actual stack : %lx - ", sp2);
message("Begin stack : %lx\n", sp1);
message("Check if same : %s\n",sp1 == sp2 ? "Ok :-)" : "No :-(");
return 1;
}