Function load_process

lab8/src/5/src/kernel/program.cpp:292–339

}

void load_process(const char *filename)
{
    interruptManager.disableInterrupt();

    PCB *process = programManager.running;
    ProcessStartStack *interruptStack =
        (ProcessStartStack *)((int)process + PAGE_SIZE - sizeof(ProcessStartStack));

    interruptStack->edi = 0;
    interruptStack->esi = 0;
    interruptStack->ebp = 0;
    interruptStack->esp_dummy = 0;
    interruptStack->ebx = 0;
    interruptStack->edx = 0;
    interruptStack->ecx = 0;
    interruptStack->eax = 0;
    interruptStack->gs = 0;

    interruptStack->fs = programManager.USER_DATA_SELECTOR;
    interruptStack->es = programManager.USER_DATA_SELECTOR;
    interruptStack->ds = programManager.USER_DATA_SELECTOR;

    interruptStack->eip = (int)filename;
    interruptStack->cs = programManager.USER_CODE_SELECTOR;   // 用户模式平坦模式
    interruptStack->eflags = (0 << 12) | (1 << 9) | (1 << 1); // IOPL, IF = 1 开中断, MBS = 1 默认

    interruptStack->esp = memoryManager.allocatePages(AddressPoolType::USER, 1);
    if (interruptStack->esp == 0)
    {
        printf("can not build process!\n");
        process->status = ProgramStatus::DEAD;
        asm_halt();
    }
    interruptStack->esp += PAGE_SIZE;
    
    // 设置进程返回地址
    int *userStack = (int *)interruptStack->esp;
    userStack -= 3;
    userStack[0] = (int)exit;
    userStack[1] = 0;
    userStack[2] = 0;

    interruptStack->esp = (int)userStack;

    interruptStack->ss = programManager.USER_STACK_SELECTOR;

    asm_start_process((int)interruptStack);
}

void ProgramManager::activateProgramPage(PCB *program)
{