ExecutionContext.h

/*
 * Copyright (c) 2026, Pedigree Developers
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted.
 */
 
#ifndef PEDIGREE_KERNEL_PROCESS_EXECUTIONCONTEXT_H
#define PEDIGREE_KERNEL_PROCESS_EXECUTIONCONTEXT_H
#include "pedigree/kernel/compiler.h"
#include "pedigree/kernel/process/AtomicStateCleanup.h"
 
#include <config.h>
 
class Thread;
 
enum class ExecutionContext {
  WaitableThread,
  AtomicThread,
  HardDeviceIrq,
  SchedulerIrq,
  HostedSyntheticIrq,
  DebuggerTrap,
};
 
class ExecutionContextState {
 public:
  ExecutionContextState(ExecutionContext context = ExecutionContext::WaitableThread)
      : m_Context(context) {}
 
  ExecutionContext current() const {
    return m_Context;
  }
 
  ExecutionContext enter(ExecutionContext context) {
    const ExecutionContext previous = m_Context;
    m_Context = context;
    return previous;
  }
 
  void restore(ExecutionContext context) {
    m_Context = context;
  }
 
  void reset() {
    m_Context = ExecutionContext::WaitableThread;
  }
 
 private:
  ExecutionContext m_Context;
};
 
class EXPORTED_PUBLIC ExecutionContextGuard {
 public:
  explicit ExecutionContextGuard(ExecutionContext context);
  ~ExecutionContextGuard();
 
 private:
  ExecutionContextGuard(const ExecutionContextGuard&);
  ExecutionContextGuard& operator=(const ExecutionContextGuard&);
 
  static void abandon(void* context);
  void restore();
 
  Thread* m_Thread;
  size_t m_StateLevel;
  ExecutionContext m_Previous;
  AtomicStateCleanupRecord m_Cleanup;
  bool m_Active;
};
 
#endif