zircon/kernel/lib/debuglog/debuglog_internal.h

// Copyright 2020 The Fuchsia Authors
//
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file or at
// https://opensource.org/licenses/MIT

#ifndef ZIRCON_KERNEL_LIB_DEBUGLOG_DEBUGLOG_INTERNAL_H_
#define ZIRCON_KERNEL_LIB_DEBUGLOG_DEBUGLOG_INTERNAL_H_

#include <kernel/event.h>
#include <kernel/mutex.h>
#include <kernel/spinlock.h>

#define DLOG_SIZE (128u * 1024u)
#define DLOG_MASK (DLOG_SIZE - 1u)

#define ALIGN4_TRUNC(n) ((n) & (~3))
#define ALIGN4(n) ALIGN4_TRUNC(((n) + 3))

struct DLog {
  explicit constexpr DLog() {}

  zx_status_t write(uint32_t severity, uint32_t flags, const void* data_ptr, size_t len);

  SpinLock lock;

  size_t head TA_GUARDED(lock) = 0;
  size_t tail TA_GUARDED(lock) = 0;

  bool panic = false;

  AutounsignalEvent event;

  DECLARE_LOCK(DLog, Mutex) readers_lock;
  fbl::DoublyLinkedList<DlogReader*> readers;

  uint8_t data[DLOG_SIZE]{0};
};

#endif  // ZIRCON_KERNEL_LIB_DEBUGLOG_DEBUGLOG_INTERNAL_H_