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#include "scheduler.h"
#include <stdlib.h>
void task_a(void) {
while (true) printk("A");
}
void task_b(void) {
while (true) printk("B");
}
constexpr uint16_t max_tasks = 256;
uint16_t curr_task = 0;
uint16_t last_task = 0;
static Scheduler::task tasks[max_tasks];
/* TODO dynamically allocate task stacks */
__attribute__((aligned(16))) uint8_t stack_a[4096] = {0};
__attribute__((aligned(16))) uint8_t stack_b[4096] = {0};
Scheduler::Scheduler(uint16_t cs) : InterruptHandler(0x00) {
printk("add_task: ", add_task({stack_a, task_a, cs}), " stack ",
uhex{reinterpret_cast<uint32_t>(tasks[1].cpu) + sizeof(cpu_state_t)}, " eip: ", uhex{tasks[1].cpu->eip}, '\n');
printk("add_task: ", add_task({stack_b, task_b, cs}), " stack ",
uhex{reinterpret_cast<uint32_t>(tasks[2].cpu) + sizeof(cpu_state_t)}, " eip: ", uhex{tasks[2].cpu->eip}, '\n');
}
uint16_t Scheduler::add_task(Scheduler::task t) {
if (last_task == (max_tasks - 1)) return 0;
uint16_t id = ++last_task;
tasks[id] = t;
return id;
}
cpu_state_t* Scheduler::trigger(cpu_state_t* cpu) {
if (curr_task != 0) {
tasks[curr_task].cpu = cpu;
}
++curr_task;
if (curr_task > last_task) curr_task = 1;
cpu = tasks[curr_task].cpu;
return cpu;
}
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