#include "Queue.h"
#include "_CJavaScriptEventLoop.h"
using namespace swift;
/// Get the next-in-queue storage slot.
static Job *&nextInQueue(Job *cur) {
return reinterpret_cast(cur->SchedulerPrivate);
}
Job *Queue::claimNext() {
if (auto job = this->HeadJob) {
this->HeadJob = nextInQueue(job);
return job;
}
return nullptr;
}
Queue::Queue() : HeadJob(nullptr), isSpinning(false) {
this->Context = (EventLoopContext) {
.Queue = this,
.Promise = nullptr,
};
}
void runEnqueuedJobs(EventLoopContext *context) {
Queue *queue = (Queue *)(context->Queue);
assert(queue->isSpinning);
while (auto *job = queue->claimNext()) {
job->run(ExecutorRef::generic());
}
queue->isSpinning = false;
}
void Queue::insertJob(swift::Job *newJob) {
Job **position = &HeadJob;
while (auto cur = *position) {
// If we find a job with lower priority, insert here.
if (cur->getPriority() < newJob->getPriority()) {
nextInQueue(newJob) = cur;
*position = newJob;
return;
}
// Otherwise, keep advancing through the queue.
position = &nextInQueue(cur);
}
nextInQueue(newJob) = nullptr;
*position = newJob;
if (!isSpinning) {
isSpinning = true;
registerEventLoopHook(runEnqueuedJobs, &this->Context);
}
}