scheduler.c

#include "scheduler.h"

void scheduler_init()
{
    next_sch_pid = 0;
    curr_sch_pid = 0;
}

process_t* get_next_process()
{
    process_t* next_process = processes[next_sch_pid];

    curr_sch_pid = next_sch_pid;
    next_sch_pid++;
    next_sch_pid = next_sch_pid % process_count;

    return next_process;
}

void scheduler(int eip, int edi, int esi, int ebp, int esp, int ebx, int edx, int ecx, int eax)
{
    print("EAX = ");
    printi(eax);

    process_t* curr_process;

    curr_process = processes[curr_sch_pid];
    next_process = get_next_process();

    if (curr_process->state == RUNNING) {
        curr_process->context.eax = eax;
        curr_process->context.ecx = ecx;
        curr_process->context.edx = edx;
        curr_process->context.ebx = ebx;
        curr_process->context.esp = esp;
        curr_process->context.ebp = ebp;
        curr_process->context.esi = esi;
        curr_process->context.edi = edi;
        curr_process->context.eip = eip;
    }

    curr_process->state = READY;

    asm(" mov %0, %%eax; \
          mov %0, %%ecx; \
          mov %0, %%edx; \
          mov %0, %%ebx; \
          mov %0, %%esi; \
          mov %0, %%edi;"
          : : 
          "r" (next_process->context.eax),
          "r" (next_process->context.ecx),
          "r" (next_process->context.edx),
          "r" (next_process->context.ebx),
          "r" (next_process->context.esi),
          "r" (next_process->context.edi));

    next_process->state = RUNNING;
}

void run_next_process()
{
    asm(" sti; \
          jmp *%0" 
          : : 
          "r" (next_process->context.eip));
}