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#include <stdint.h>
#include <kernel/syscall/syscall.h>
#include <kernel/interrupts/interrupts.h>
#include <kernel/graphics/vesa.h>
#include <kernel/io/io.h>
DEFN_SYSCALL1(vesa_draw_string, 0, const char *);
DEFN_SYSCALL1(vesa_draw_number, 1, int);
DEFN_SYSCALL1(serial_write, 2, const char *);
static void *syscalls[3] = {
&vesa_draw_string,
&vesa_draw_number,
&serial_write,
};
uint32_t num_syscalls = 3;
void syscall_handler(struct regs *r)
{
serial_write("SYSCALL");
if (r->eax >= num_syscalls)
return;
void *location = syscalls[r->eax];
int ret;
asm (" \
push %1; \
push %2; \
push %3; \
push %4; \
push %5; \
call *%6; \
pop %%ebx; \
pop %%ebx; \
pop %%ebx; \
pop %%ebx; \
pop %%ebx; \
" : "=a" (ret) : "r" (r->edi), "r" (r->esi), "r" (r->edx), "r" (r->ecx), "r" (r->ebx), "r" (location));
r->eax = ret;
}
void syscalls_install()
{
irq_install_handler(0x80, syscall_handler);
}
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