text: /*
   * Copyright (c) 2013-2019 Huawei Technologies Co., Ltd. All rights reserved.
   * Copyright (c) 2020-2021 Huawei Device Co., Ltd. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without modification,
   * are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice, this list of
   *    conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright notice, this list
   *    of conditions and the following disclaimer in the documentation and/or other materials
   *    provided with the distribution.
   *
   * 3. Neither the name of the copyright holder nor the names of its contributors may be used
   *    to endorse or promote products derived from this software without specific prior written
   *    permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
   * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
   * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
   * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include "los_hilog.h"
  #include "los_init.h"
  #include "los_mp.h"
  #include "los_mux.h"
  #include "los_process_pri.h"
  #include "los_task_pri.h"
  #include "fs/file.h"
  #include "fs/driver.h"
  #include "los_vm_map.h"
  #include "los_vm_lock.h"
  #include "user_copy.h"
  
  #define HILOG_BUFFER LOSCFG_HILOG_BUFFER_SIZE
  #define DRIVER_MODE 0666
  #define HILOG_DRIVER "/dev/hilog"
  
  struct HiLogEntry {
      unsigned int len;
      unsigned int hdrSize;
      unsigned int pid : 16;
      unsigned int taskId : 16;
      unsigned int sec;
      unsigned int nsec;
      unsigned int reserved;
      char msg[0];
  };
  
  ssize_t HilogRead(struct file *filep, char __user *buf, size_t count);
  ssize_t HilogWrite(struct file *filep, const char __user *buf, size_t count);
  int HiLogOpen(struct file *filep);
  int HiLogClose(struct file *filep);
  
  static ssize_t HiLogWrite(struct file *filep, const char *buffer, size_t bufLen);
  static ssize_t HiLogRead(struct file *filep, char *buffer, size_t bufLen);
  
  STATIC struct file_operations_vfs g_hilogFops = {
      HiLogOpen,  /* open */
      HiLogClose, /* close */
      HiLogRead,  /* read */
      HiLogWrite, /* write */
      NULL,       /* seek */
      NULL,       /* ioctl */
      NULL,       /* mmap */
  #ifndef CONFIG_DISABLE_POLL
      NULL, /* poll */
  #endif
      NULL, /* unlink */
  };
  
  struct HiLogCharDevice {
      int flag;
      LosMux mtx;
      unsigned char *buffer;
      wait_queue_head_t wq;
      size_t writeOffset;
      size_t headOffset;
      size_t size;
      size_t count;
  } g_hiLogDev;
  
  static inline unsigned char *HiLogBufferHead(void)
  {
      return g_hiLogDev.buffer + g_hiLogDev.headOffset;
  }
  
  int HiLogOpen(struct file *filep)
  {
      (void)filep;
      return 0;
  }
  
  int HiLogClose(struct file *filep)
  {
      (void)filep;
      return 0;
  }
  
  static void HiLogBufferInc(size_t sz)
  {
      if (g_hiLogDev.size + sz <= HILOG_BUFFER) {
          g_hiLogDev.size += sz;
          g_hiLogDev.writeOffset += sz;
          g_hiLogDev.writeOffset %= HILOG_BUFFER;
          g_hiLogDev.count++;
      }
  }
  
  static void HiLogBufferDec(size_t sz)
  {
      if (g_hiLogDev.size >= sz) {
          g_hiLogDev.size -= sz;
          g_hiLogDev.headOffset += sz;
          g_hiLogDev.headOffset %= HILOG_BUFFER;
          g_hiLogDev.count--;
      }
  }
  
  static int HiLogBufferCopy(unsigned char *dst, unsigned dstLen, const unsigned char *src, size_t srcLen)
  {
      int retval = -1;
      size_t minLen = (dstLen > srcLen) ? srcLen : dstLen;
  
      if (LOS_IsUserAddressRange((VADDR_T)(UINTPTR)dst, minLen) &&
          LOS_IsUserAddressRange((VADDR_T)(UINTPTR)src, minLen)) {
          return retval;
      }
  
      if (LOS_IsUserAddressRange((VADDR_T)(UINTPTR)dst, minLen)) {
          retval = LOS_ArchCopyToUser(dst, src, minLen);
      } else if (LOS_IsUserAddressRange((VADDR_T)(UINTPTR)src, minLen)) {
          retval = LOS_ArchCopyFromUser(dst, src, minLen);
      } else {
          retval = memcpy_s(dst, dstLen, src, srcLen);
      }
      return retval;
  }
  
  static int HiLogReadRingBuffer(unsigned char *buffer, size_t bufLen)
  {
      size_t retval;
      size_t bufLeft = HILOG_BUFFER - g_hiLogDev.headOffset;
      if (bufLeft > bufLen) {
          retval = HiLogBufferCopy(buffer, bufLen, HiLogBufferHead(), bufLen);
      } else {
          retval = HiLogBufferCopy(buffer, bufLen, HiLogBufferHead(), bufLeft);
          if (retval < 0) {
              return retval;
          }
  
          retval = HiLogBufferCopy(buffer + bufLeft, bufLen - bufLeft, g_hiLogDev.buffer, bufLen - bufLeft);
      }
      return retval;
  }
  
  static ssize_t HiLogRead(struct file *filep, char *buffer, size_t bufLen)
  {
      size_t retval;
      struct HiLogEntry header;
  
      (void)filep;
      wait_event_interruptible(g_hiLogDev.wq, (g_hiLogDev.size > 0));
  
      (VOID)LOS_MuxAcquire(&g_hiLogDev.mtx);
      retval = HiLogReadRingBuffer((unsigned char *)&header, sizeof(header));
      if (retval < 0) {
          retval = -EINVAL;
          goto out;
      }
  
      if (bufLen < header.len + sizeof(header)) {
          dprintf("buffer too small,bufLen=%d, header.len=%d,%d\n", bufLen, header.len, header.hdrSize);
          retval = -ENOMEM;
          goto out;
      }
  
      HiLogBufferDec(sizeof(header));
  
      retval = HiLogBufferCopy((unsigned char *)buffer, bufLen, (unsigned char *)&header, sizeof(header));
      if (retval < 0) {
          retval = -EINVAL;
          goto out;
      }
  
      retval = HiLogReadRingBuffer((unsigned char *)(buffer + sizeof(header)), header.len);
      if (retval < 0) {
          retval = -EINVAL;
          goto out;
      }
  
      HiLogBufferDec(header.len);
      retval = header.len + sizeof(header);
  out:
      if (retval == -ENOMEM) {
          // clean ring buffer
          g_hiLogDev.writeOffset = 0;
          g_hiLogDev.headOffset = 0;
          g_hiLogDev.size = 0;
          g_hiLogDev.count = 0;
      }
      (VOID)LOS_MuxRelease(&g_hiLogDev.mtx);
      return retval;
  }
  
  static int HiLogWriteRingBuffer(unsigned char *buffer, size_t bufLen)
  {
      int retval;
      size_t bufLeft = HILOG_BUFFER - g_hiLogDev.writeOffset;
      if (bufLen > bufLeft) {
          retval = HiLogBufferCopy(g_hiLogDev.buffer + g_hiLogDev.writeOffset, bufLeft, buffer, bufLeft);
          if (retval) {
              return -1;
          }
          retval = HiLogBufferCopy(g_hiLogDev.buffer, HILOG_BUFFER, buffer + bufLeft, bufLen - bufLeft);
      } else {
          retval = HiLogBufferCopy(g_hiLogDev.buffer + g_hiLogDev.writeOffset, bufLeft, buffer, bufLen);
      }
      if (retval < 0) {
          return -1;
      }
      return 0;
  }
  
  static void HiLogHeadInit(struct HiLogEntry *header, size_t len)
  {
      struct timespec now;
      int ret;
  
      ret = clock_gettime(CLOCK_REALTIME, &now);
      if (ret != 0) {
          dprintf("In %s line %d,clock_gettime fail\n", __FUNCTION__, __LINE__);
          return;
      }
  
      header->len = len;
      header->pid = LOS_GetCurrProcessID();
      header->taskId = LOS_CurTaskIDGet();
      header->sec = now.tv_sec;
      header->nsec = now.tv_nsec;
      header->hdrSize = sizeof(struct HiLogEntry);
  }
  
  static void HiLogCoverOldLog(size_t bufLen)
  {
      int retval;
      struct HiLogEntry header;
      size_t totalSize = bufLen + sizeof(struct HiLogEntry);
      static int dropLogLines = 0;
      static int isLastTimeFull = 0;
      int isThisTimeFull = 0;
  
      while (totalSize + g_hiLogDev.size > HILOG_BUFFER) {
          retval = HiLogReadRingBuffer((unsigned char *)&header, sizeof(header));
          if (retval < 0) {
              break;
          }
  
          dropLogLines++;
          isThisTimeFull = 1;
          isLastTimeFull = 1;
          HiLogBufferDec(sizeof(header));
          HiLogBufferDec(header.len);
      }
      if (isLastTimeFull == 1 && isThisTimeFull == 0) {
          /* so we can only print one log if hilog ring buffer is full in a short time */
          if (dropLogLines > 0) {
              dprintf("hilog ringbuffer full, drop %d line(s) log\n", dropLogLines);
          }
          isLastTimeFull = 0;
          dropLogLines = 0;
      }
  }
  
  int HiLogWriteInternal(const char *buffer, size_t bufLen)
  {
      struct HiLogEntry header;
      int retval;
      LosTaskCB *runTask =  (LosTaskCB *)OsCurrTaskGet();
  
      if ((g_hiLogDev.buffer == NULL) || (OS_INT_ACTIVE) || (runTask->taskStatus & OS_TASK_FLAG_SYSTEM_TASK)) {
          PRINTK("%s\n", buffer);
          return -EAGAIN;
      }
  
      (VOID)LOS_MuxAcquire(&g_hiLogDev.mtx);
      HiLogCoverOldLog(bufLen);
      HiLogHeadInit(&header, bufLen);
  
      retval = HiLogWriteRingBuffer((unsigned char *)&header, sizeof(header));
      if (retval) {
          retval = -ENODATA;
          goto out;
      }
      HiLogBufferInc(sizeof(header));
  
      retval = HiLogWriteRingBuffer((unsigned char *)(buffer), header.len);
      if (retval) {
          retval = -ENODATA;
          goto out;
      }
  
      HiLogBufferInc(header.len);
  
      retval = header.len;
  
  out:
      (VOID)LOS_MuxRelease(&g_hiLogDev.mtx);
      if (retval > 0) {
          wake_up_interruptible(&g_hiLogDev.wq);
      }
      if (retval < 0) {
          dprintf("write fail retval=%d\n", retval);
      }
      return retval;
  }
  
  static ssize_t HiLogWrite(struct file *filep, const char *buffer, size_t bufLen)
  {
      (void)filep;
      if (bufLen + sizeof(struct HiLogEntry) > HILOG_BUFFER) {
          dprintf("input too large\n");
          return -ENOMEM;
      }
  
      return HiLogWriteInternal(buffer, bufLen);
  }
  
  static void HiLogDeviceInit(void)
  {
      g_hiLogDev.buffer = LOS_MemAlloc((VOID *)OS_SYS_MEM_ADDR, HILOG_BUFFER);
      if (g_hiLogDev.buffer == NULL) {
          dprintf("In %s line %d,LOS_MemAlloc fail\n", __FUNCTION__, __LINE__);
      }
  
      init_waitqueue_head(&g_hiLogDev.wq);
      LOS_MuxInit(&g_hiLogDev.mtx, NULL);
  
      g_hiLogDev.writeOffset = 0;
      g_hiLogDev.headOffset = 0;
      g_hiLogDev.size = 0;
      g_hiLogDev.count = 0;
  }
  
  int OsHiLogDriverInit(VOID)
  {
      HiLogDeviceInit();
      return register_driver(HILOG_DRIVER, &g_hilogFops, DRIVER_MODE, NULL);
  }
  
  LOS_MODULE_INIT(OsHiLogDriverInit, LOS_INIT_LEVEL_KMOD_EXTENDED);
  