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KSMb wrote:when i try to fire some interrupts(from the kernel) this function does not print the related message(from the array).

KSMb wrote:If i try to print only the interrupt number it gaves me strange symbols and not the correct number, so i think it's a problem with the IDT itself.

Octocontrabass wrote:Your isr_common_stub passes a pointer to a struct, but your isr_handler expects a struct. You won't get anything useful until you reconcile this difference. Keep in mind that the ABI allows C functions to clobber their arguments, so you probably want to use a pointer to a struct.

Octocontrabass wrote: Also, there's no need for "call eax", the linker will ensure "call isr_handler" works correctly. (And while we're at it, save an instruction and use "push esp" to put the pointer on the stack.)

isr_handler

Octocontrabass wrote: Even after you fix the above issue, this still won't work since you're not converting the integer to a string. Don't you get a compiler warning about passing an integer type to a function expecting a pointer?

atoi()

MichaelPetch wrote:Octo beat me to it, and you can find a discussion/solution about the issue here: viewtopic.php?f=1&t=33636&p=289580&hili ... _t#p289580

Upon further review of your code there is a mixture of a fix already in place. The parameters to irs_handler is passed properly, just your delcaration and prototype in the C code are wrong. In kernel/include/kernel/isrs.h it should be:

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void isr_handler(registers_t *regs);

and in kernel/arch/i386/isrs.c your isr_handler function should be:

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void isr_handler(registers_t *regs) {
   terminal_writestring("Received interrupt: ");
   terminal_writestring(interrupts_messages[(uint8_t)regs->int_no]); // Print message associated to num
   // terminal_writestring(regs->int_no);
   terminal_writestring("\n");
}

As Octo points out to use terminal_writestring to print an integer you'd have to write a function to do that (ie: itoa).

There is one other significant issue even if you fix the code above will still prevent the right interrupt number from being accessed properly. In kernel/include/kernel/isrs.h you have:

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 // This struct will be used to store all registers we've pushed
typedef struct registers {
    uint32_t ds; // Data segment selector
    uint32_t edi, esi, ebp, esp, ebx, edx, ecx, eax; // Pushed by pusha
    uint32_t int_no, err_code; // Interrupt number and error code
    uint32_t eip, cs, eflags, useresp, ss; // Pushed by the CPU itself
} registers_t;

The problem is that in kernel/arch/i386/boot.asm you do:

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    pusha ; Pushes EDI, ESI, EBP, ESP, EBX, EDX, ECX and EAX registers
    push ds
    push es
    push fs
    push gs

What you push has to exactly match the registers_t structure (in reverse order). You push DS, ES, FS, and GS and not just DS. Because these two things don't match you will be accessing data in registers_t at incorrect offsets. registers_t should look like:

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typedef struct registers {
    uint32_t gs, fs, es, ds; // Segment selectors
    uint32_t edi, esi, ebp, esp, ebx, edx, ecx, eax; // Pushed by pusha
    uint32_t int_no, err_code; // Interrupt number and error code
    uint32_t eip, cs, eflags, useresp, ss; // Pushed by the CPU itself
} registers_t;