Logstorage: Sync behavior bug fix

This commit fixes couple of unexpected behavior on Logstorage sync behavior.
- A log file is created only if necessary to avoid creating an empty log file.
- The cache is synced with the condition:
  1) When the ring buffer is not wrapped around, the cache is synced from
     last sync offset to current offset
  2) When the ring buffer is wrapped around for first time and current offset
     is smaller than last sync offset, the cache is synced from last sync
     offset to end sync offset, and then from beginning to current offset
  3) Otherwise, the cache is synced from offset where the log message starts
     to end sync offset, and then from beginning to current offset

Signed-off-by: Saya Sugiura <ssugiura@jp.adit-jv.com>

7 files changed, 327 insertions, 516 deletions

diff --git a/src/daemon/dlt_daemon_offline_logstorage.c b/src/daemon/dlt_daemon_offline_logstorage.c
index f915086..8a6dd75 100644
--- a/src/daemon/dlt_daemon_offline_logstorage.c
+++ b/src/daemon/dlt_daemon_offline_logstorage.c
@@ -1115,9 +1115,20 @@ int dlt_daemon_logstorage_cleanup(DltDaemon *daemon,
         /* call disconnect on all currently connected devices */
         if (daemon->storage_handle[i].connection_type ==
             DLT_OFFLINE_LOGSTORAGE_DEVICE_CONNECTED)
+        {
+            (&daemon->storage_handle[i])->uconfig.logfile_counteridxlen =
+                                        daemon_local->flags.offlineLogstorageMaxCounterIdx;
+            (&daemon->storage_handle[i])->uconfig.logfile_delimiter =
+                                        daemon_local->flags.offlineLogstorageDelimiter;
+            (&daemon->storage_handle[i])->uconfig.logfile_maxcounter =
+                                        daemon_local->flags.offlineLogstorageMaxCounter;
+            (&daemon->storage_handle[i])->uconfig.logfile_timestamp =
+                                        daemon_local->flags.offlineLogstorageTimestamp;
+
             dlt_logstorage_device_disconnected(
                 &daemon->storage_handle[i],
                 DLT_LOGSTORAGE_SYNC_ON_DAEMON_EXIT);
+        }
 
     return 0;
 }
diff --git a/src/offlinelogstorage/dlt_offline_logstorage.c b/src/offlinelogstorage/dlt_offline_logstorage.c
index 483bf8a..fe1af71 100644
--- a/src/offlinelogstorage/dlt_offline_logstorage.c
+++ b/src/offlinelogstorage/dlt_offline_logstorage.c
@@ -89,11 +89,11 @@ DLT_STATIC void dlt_logstorage_filter_config_free(DltLogStorageFilterConfig *dat
  * @return 0 on success, -1 on error
  */
 DLT_STATIC int dlt_logstorage_list_destroy(DltLogStorageFilterList **list,
+                                           DltLogStorageUserConfig *uconfig,
+                                           char *dev_path,
                                            int reason)
 {
     DltLogStorageFilterList *tmp = NULL;
-    DltLogStorageUserConfig *uconfig = NULL;
-    char *dev_path = NULL;
 
     while (*(list) != NULL) {
         tmp = *list;
@@ -295,7 +295,8 @@ void dlt_logstorage_free(DltLogStorage *handle, int reason)
         return;
     }
 
-    dlt_logstorage_list_destroy(&(handle->config_list), reason);
+    dlt_logstorage_list_destroy(&(handle->config_list), &handle->uconfig,
+                                handle->device_mount_point, reason);
 }
 
 
@@ -2032,6 +2033,8 @@ int dlt_logstorage_write(DltLogStorage *handle,
 
         if (ret == 0) { /* log data (write) */
             ret = config[i]->dlt_logstorage_write(config[i],
+                                                  uconfig,
+                                                  handle->device_mount_point,
                                                   data1,
                                                   size1,
                                                   data2,
diff --git a/src/offlinelogstorage/dlt_offline_logstorage.h b/src/offlinelogstorage/dlt_offline_logstorage.h
index e28e535..33f55f6 100644
--- a/src/offlinelogstorage/dlt_offline_logstorage.h
+++ b/src/offlinelogstorage/dlt_offline_logstorage.h
@@ -54,7 +54,6 @@
 #define DLT_OFFLINE_LOGSTORAGE_H
 
 #include <search.h>
-#include <stdbool.h>
 #include "dlt_common.h"
 #include "dlt-daemon_cfg.h"
 #include "dlt_config_file_parser.h"
@@ -125,6 +124,7 @@ typedef struct
     unsigned int offset;          /* current write offset */
     unsigned int wrap_around_cnt; /* wrap around counter */
     unsigned int last_sync_offset; /* last sync position */
+    unsigned int end_sync_offset; /* end position of previous round */
 } DltLogStorageCacheFooter;
 
 typedef struct
@@ -164,6 +164,8 @@ struct DltLogStorageFilterConfig
                                   char *dev_path,
                                   int log_msg_size);
     int (*dlt_logstorage_write)(DltLogStorageFilterConfig *config,
+                                DltLogStorageUserConfig *file_config,
+                                char *dev_path,
                                 unsigned char *data1,
                                 int size1,
                                 unsigned char *data2,
@@ -180,10 +182,6 @@ struct DltLogStorageFilterConfig
     void *cache;                    /* log data cache */
     unsigned int specific_size;     /* cache size used for specific_size sync strategy */
     unsigned int current_write_file_offset;    /* file offset for specific_size sync strategy */
-    unsigned int total_write_count; /* total count of data need to sync to file */
-    bool pre_cache_sync;            /* sync done in previous wrap around */
-    bool cur_cache_sync;            /* sync done in present cache */
-    bool sync_from_start;           /* sync done from start of cache */
     DltLogStorageFileList *records; /* File name list */
 };
 
diff --git a/src/offlinelogstorage/dlt_offline_logstorage_behavior.c b/src/offlinelogstorage/dlt_offline_logstorage_behavior.c
index 5d9576b..f4d1d97 100644
--- a/src/offlinelogstorage/dlt_offline_logstorage_behavior.c
+++ b/src/offlinelogstorage/dlt_offline_logstorage_behavior.c
@@ -28,6 +28,7 @@
 #include <sys/stat.h>
 #include <unistd.h>
 #include <stdlib.h>
+#include <errno.h>
 
 #include "dlt_offline_logstorage.h"
 #include "dlt_offline_logstorage_behavior.h"
@@ -75,8 +76,11 @@ void dlt_logstorage_log_file_name(char *log_file_name,
         snprintf(file_index, 10, "%d", idx);
         digit_idx = strlen(file_index);
 
-        for (i = 0; i < (file_config->logfile_counteridxlen - digit_idx); i++)
-            strcat(log_file_name, "0");
+        if (file_config->logfile_counteridxlen > digit_idx)
+        {
+            for (i = 0 ; i < (file_config->logfile_counteridxlen - digit_idx) ; i++)
+                strcat(log_file_name, "0");
+        }
     }
 
     strcat(log_file_name, file_index);
@@ -528,6 +532,35 @@ DLT_STATIC int dlt_logstorage_find_dlt_header(void *ptr,
 }
 
 /**
+ * dlt_logstorage_find_last_dlt_header
+ *
+ * search for last dlt header in cache
+ *
+ * @param ptr         cache starting position
+ * @param offset      offset
+ * @param cnt         count
+ * @return index on success, -1 on error
+ */
+DLT_STATIC int dlt_logstorage_find_last_dlt_header(void *ptr,
+                                                   unsigned int offset,
+                                                   unsigned int cnt)
+{
+    char substring[] = {'D', 'L', 'T', 0x01};
+    while(cnt > 0)
+    {
+        if (*((char *)(ptr + offset + cnt)) == 'D')
+        {
+            if (strncmp(ptr + offset + cnt, substring, 4) == 0)
+            {
+                return cnt;
+            }
+        }
+        cnt--;
+    }
+    return -1;
+}
+
+/**
  * dlt_logstorage_check_write_ret
  *
  * check the return value of fwrite
@@ -551,121 +584,12 @@ DLT_STATIC void dlt_logstorage_check_write_ret(DltLogStorageFilterConfig *config
             dlt_vlog(LOG_ERR, "%s: failed to flush log file\n", __func__);
 
         if (fsync(fileno(config->log)) != 0)
-            dlt_vlog(LOG_ERR, "%s: failed to sync log file\n", __func__);
-    }
-}
-
-/**
- * dlt_logstorage_sync_create_new_file
- *
- * Write the log message and open new log file
- *
- * @param config            DltLogStorageFilterConfig
- * @param file_config       DltLogStorageUserConfig
- * @param dev_path          Storage device mount point
- * @param remain_file_size  log file remaining size
- * @return 0 on success, -1 on error
- */
-DLT_STATIC DltReturnValue dlt_logstorage_sync_create_new_file(
-    DltLogStorageFilterConfig *config,
-    DltLogStorageUserConfig *file_config,
-    char *dev_path,
-    unsigned int remain_file_size)
-{
-    int index = 0;
-    int ret;
-    unsigned int cache_offset = 0;
-    unsigned int count = 0;
-    DltLogStorageCacheFooter *footer = NULL;
-
-    if ((config == NULL) || (file_config == NULL) || (dev_path == NULL)) {
-        dlt_vlog(LOG_ERR, "%s: cannot retrieve config information\n", __func__);
-        return DLT_RETURN_WRONG_PARAMETER;
-    }
-
-    footer = (DltLogStorageCacheFooter *)(config->cache +
-                                          config->file_size);
-
-    if (footer == NULL) {
-        dlt_vlog(LOG_ERR, "%s: Cannot retrieve cache information\n", __func__);
-        return DLT_RETURN_WRONG_PARAMETER;
-    }
-
-    /* sync capable data to file */
-    if (footer->offset >= footer->last_sync_offset) {
-        count = config->file_size - footer->offset;
-
-        if (count > remain_file_size)
-            count = remain_file_size;
-
-        index = dlt_logstorage_find_dlt_header(config->cache, footer->offset, count);
-        cache_offset = footer->offset;
-    }
-    else {
-        count = config->file_size - footer->last_sync_offset;
-
-        if (count > remain_file_size)
-            count = remain_file_size;
-
-        index = dlt_logstorage_find_dlt_header(config->cache,
-                                               footer->last_sync_offset,
-                                               count);
-        cache_offset = footer->last_sync_offset;
-
-    }
-
-    if (index >= 0) {
-        ret = fwrite(config->cache + cache_offset + index, count - index, 1, config->log);
-        dlt_logstorage_check_write_ret(config, ret);
-        config->current_write_file_offset += count - index;
-    }
-
-    if (footer->last_sync_offset == 0)
-        footer->last_sync_offset = footer->offset + count;
-    else
-        footer->last_sync_offset += count;
-
-    config->total_write_count -= count;
-
-    /* sync data to current file in case of file is not full */
-    if (config->current_write_file_offset < config->file_size) {
-        count = config->file_size - config->current_write_file_offset;
-
-        if (footer->last_sync_offset < config->file_size) {
-            ret = fwrite(config->cache + footer->last_sync_offset, count, 1, config->log);
-            dlt_logstorage_check_write_ret(config, ret);
-            footer->last_sync_offset += count;
-        }
-        /* sync remaining amount of file from start of cache */
-        else {
-            config->sync_from_start = 1;
-
-            if (count > footer->offset)
-                count = footer->offset;
-
-            ret = fwrite(config->cache, count, 1, config->log);
-            dlt_logstorage_check_write_ret(config, ret);
-            footer->last_sync_offset = count;
-        }
-
-        config->total_write_count -= count;
-    }
-
-    config->current_write_file_offset = 0;
-    fclose(config->log);
-    config->log = NULL;
-
-    /* get always a new file */
-    if (dlt_logstorage_prepare_on_msg(config,
-                                      file_config,
-                                      dev_path,
-                                      config->file_size) != 0) {
-        dlt_vlog(LOG_ERR,
-                 "%s: failed to prepare log file for file_size\n", __func__);
-        return DLT_RETURN_ERROR;
+            /* some filesystem doesn't support fsync() */
+            if (errno != ENOSYS)
+            {
+                dlt_vlog(LOG_ERR, "%s: failed to sync log file\n", __func__);
+            }
     }
-
-    return DLT_RETURN_OK;
 }
 
 /**
@@ -676,115 +600,108 @@ DLT_STATIC DltReturnValue dlt_logstorage_sync_create_new_file(
  * @param config        DltLogStorageFilterConfig
  * @param file_config   DltLogStorageUserConfig
  * @param dev_path      Storage device mount point path
+ * @param footer        DltLogStorageCacheFooter
+ * @param start_offset  Start offset of the cache
+ * @param end_offset    End offset of the cache
  * @return 0 on success, -1 on error
  */
-DLT_STATIC DltReturnValue dlt_logstorage_sync_to_file(
-    DltLogStorageFilterConfig *config,
-    DltLogStorageUserConfig *file_config,
-    char *dev_path)
+DLT_STATIC int dlt_logstorage_sync_to_file(DltLogStorageFilterConfig *config,
+                                           DltLogStorageUserConfig *file_config,
+                                           char *dev_path,
+                                           DltLogStorageCacheFooter *footer,
+                                           unsigned int start_offset,
+                                           unsigned int end_offset)
 {
     int ret = 0;
-    unsigned int remain_file_size = 0;
-    unsigned int count = 0;
-    DltLogStorageCacheFooter *footer = NULL;
+    int start_index = 0;
+    int end_index = 0;
+    int count;
+    int remain_file_size;
 
-    if ((config == NULL) || (file_config == NULL) || (dev_path == NULL)) {
+    if ((config == NULL) || (file_config == NULL) || (dev_path == NULL) ||
+        (footer == NULL))
+    {
         dlt_vlog(LOG_ERR, "%s: cannot retrieve config information\n", __func__);
-        return DLT_RETURN_WRONG_PARAMETER;
-    }
-
-    footer = (DltLogStorageCacheFooter *)(config->cache + config->file_size);
-
-    if (footer == NULL) {
-        dlt_vlog(LOG_ERR, "%s: Cannot retrieve cache information\n", __func__);
-        return DLT_RETURN_WRONG_PARAMETER;
+        return -1;
     }
 
-    count = footer->offset - footer->last_sync_offset;
+    count = end_offset - start_offset;
     remain_file_size = config->file_size - config->current_write_file_offset;
 
-    /* sync data to file if required sync data exceeds remaining file size */
-    if (count > remain_file_size) {
-        ret = fwrite(config->cache + footer->last_sync_offset, remain_file_size, 1, config->log);
-        dlt_logstorage_check_write_ret(config, ret);
-        config->current_write_file_offset += remain_file_size;
-        footer->last_sync_offset += remain_file_size;
-
-        count = footer->offset - footer->last_sync_offset;
-        config->current_write_file_offset = 0;
-        fclose(config->log);
-        config->log = NULL;
-
-        /* get always a new file */
-        if (dlt_logstorage_prepare_on_msg(config,
-                                          file_config,
-                                          dev_path,
-                                          config->file_size) != 0) {
-            dlt_vlog(LOG_ERR,
-                     "%s: failed to prepare log file for file_size\n", __func__);
-            return DLT_RETURN_ERROR;
-        }
-    }
-
-    ret = fwrite(config->cache + footer->last_sync_offset, count, 1, config->log);
-    dlt_logstorage_check_write_ret(config, ret);
-    config->current_write_file_offset += count;
-    footer->last_sync_offset = footer->offset;
-    config->cur_cache_sync = 1;
-
-    return DLT_RETURN_OK;
-}
-
-/**
- * dlt_logstorage_sync_capable_data_to_file
- *
- * Write the log message to log file
- *
- * @param config        DltLogStorageFilterConfig
- * @param index_status  check for index is required or not
- * @return 0 on success, -1 on error
- */
-DLT_STATIC DltReturnValue dlt_logstorage_sync_capable_data_to_file(
-    DltLogStorageFilterConfig *config,
-    int index_status)
-{
-    int ret = 0;
-    int index = 0;
-    unsigned int count = 0;
-    DltLogStorageCacheFooter *footer = NULL;
+    if (count > remain_file_size)
+    {
+        /* Check if more than one message can fit into the remaining file */
+        start_index = dlt_logstorage_find_dlt_header(config->cache, start_offset,
+                                                     remain_file_size);
+        end_index = dlt_logstorage_find_last_dlt_header(config->cache,
+                                                     start_offset + start_index,
+                                                     remain_file_size - start_index);
+        count = end_index - start_index;
+
+        if ((start_index >= 0) && (end_index > start_index) &&
+            (count > 0) && (count <= remain_file_size))
+        {
+            /* Prepare log file */
+            if (config->log == NULL)
+            {
+                if (dlt_logstorage_prepare_on_msg(config, file_config, dev_path,
+                                                  config->file_size) != 0)
+                {
+                    dlt_vlog(LOG_ERR, "%s: failed to prepare log file\n",
+                             __func__);
+                    return -1;
+                }
+            }
 
-    if (config == NULL) {
-        dlt_vlog(LOG_ERR, "%s: cannot retrieve config information\n", __func__);
-        return DLT_RETURN_WRONG_PARAMETER;
-    }
+            ret = fwrite(config->cache + start_offset + start_index, count, 1,
+                         config->log);
+            dlt_logstorage_check_write_ret(config, ret);
 
-    footer = (DltLogStorageCacheFooter *)(config->cache + config->file_size);
+            /* Close log file */
+            fclose(config->log);
+            config->log = NULL;
+            config->current_write_file_offset = 0;
 
-    if (footer == NULL) {
-        dlt_vlog(LOG_ERR, "%s: Cannot retrieve cache information\n", __func__);
-        return DLT_RETURN_WRONG_PARAMETER;
+            footer->last_sync_offset = start_offset + count;
+            start_offset = footer->last_sync_offset;
+        }
+        else
+        {
+            /* Close log file */
+            fclose(config->log);
+            config->log = NULL;
+            config->current_write_file_offset = 0;
+        }
     }
 
-    count = config->file_size - footer->last_sync_offset;
+    start_index = dlt_logstorage_find_dlt_header(config->cache, start_offset,
+                                                 count);
+    count = end_offset - start_offset - start_index;
 
-    if (index_status == 1)
-        index = dlt_logstorage_find_dlt_header(config->cache,
-                                               footer->last_sync_offset,
-                                               count);
+    if ((start_index >= 0) && (count > 0))
+    {
+        /* Prepare log file */
+        if (config->log == NULL)
+        {
+            if (dlt_logstorage_prepare_on_msg(config, file_config, dev_path,
+                                              config->file_size) != 0)
+            {
+                dlt_vlog(LOG_ERR, "%s: failed to prepare log file\n", __func__);
+                return -1;
+            }
+        }
 
-    if ((count > 0) && (index >= 0)) {
-        ret = fwrite(config->cache + footer->last_sync_offset + index,
-                     count - index,
-                     1,
+        ret = fwrite(config->cache + start_offset + start_index, count, 1,
                      config->log);
         dlt_logstorage_check_write_ret(config, ret);
-        config->current_write_file_offset += count - index;
+
+        config->current_write_file_offset += count;
+        footer->last_sync_offset = end_offset;
     }
 
-    config->total_write_count -= count;
-    footer->last_sync_offset = 0;
+    footer->wrap_around_cnt = 0;
 
-    return DLT_RETURN_OK;
+    return 0;
 }
 
 /**
@@ -858,6 +775,8 @@ int dlt_logstorage_prepare_on_msg(DltLogStorageFilterConfig *config,
  * @return 0 on success, -1 on error
  */
 int dlt_logstorage_write_on_msg(DltLogStorageFilterConfig *config,
+                                DltLogStorageUserConfig *file_config,
+                                char *dev_path,
                                 unsigned char *data1,
                                 int size1,
                                 unsigned char *data2,
@@ -867,8 +786,11 @@ int dlt_logstorage_write_on_msg(DltLogStorageFilterConfig *config,
 {
     int ret;
 
-    if ((config == NULL) || (data1 == NULL) || (data2 == NULL) || (data3 == NULL))
+    if ((config == NULL) || (data1 == NULL) || (data2 == NULL) || (data3 == NULL) ||
+        (file_config == NULL) || (dev_path == NULL))
+    {
         return -1;
+    }
 
     ret = fwrite(data1, 1, size1, config->log);
 
@@ -956,75 +878,54 @@ int dlt_logstorage_prepare_msg_cache(DltLogStorageFilterConfig *config,
 
     log_msg_size = log_msg_size; /* satisfy compiler */
 
-    /* create file to sync cache into later */
-    if (config->log == NULL) {
-
-        if ((DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                    DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0) &&
-            (config->specific_size > config->file_size)) {
-            dlt_log(LOG_ERR,
-                    "Cannot prepare log file for ON_DAEMON_SPECIFIC_SIZE sync\n");
-            return -1;
-        }
-        else
-        /* get always a new file */
-        if (dlt_logstorage_prepare_on_msg(config,
-                                          file_config,
-                                          dev_path,
-                                          config->file_size) != 0) {
-            dlt_log(LOG_ERR,
-                    "Cannot prepare log file for ON_DAEMON_EXIT sync\n");
-            return -1;
-        }
+    /* check specific size is smaller than file size */
+    if ((DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
+                     DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0) &&
+                     (config->specific_size > config->file_size))
+    {
+        dlt_log(LOG_ERR,
+                "Cache size is larger than file size. "
+                "Cannot prepare log file for ON_SPECIFIC_SIZE sync\n");
+        return -1;
     }
 
-    if (config->cache == NULL) {
+    if (config->cache == NULL)
+    {
+        unsigned int cache_size = 0;
 
         /* check for sync_specific_size strategy */
         if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                   DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0) {
-            /* check total logstorage cache size */
-            if ((g_logstorage_cache_size +
-                 config->specific_size +
-                 sizeof(DltLogStorageCacheFooter)) >
-                g_logstorage_cache_max) {
-                dlt_log(LOG_ERR, "Max size of Logstorage Cache already used.");
-                return -1;
-            }
-
-            /* create cache */
-            config->cache = calloc(1,
-                                   config->specific_size +
-                                   sizeof(DltLogStorageCacheFooter));
-
-            /* update current used cache size */
-            g_logstorage_cache_size = config->specific_size +
-                sizeof(DltLogStorageCacheFooter);
+               DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0)
+        {
+            cache_size = config->specific_size;
+        }
+        else  /* other cache strategies */
+        {
+            cache_size = config->file_size;
         }
-        else { /* other cache strategies */
-
-            /* check total logstorage cache size */
-            if ((g_logstorage_cache_size +
-                 config->file_size +
-                 sizeof(DltLogStorageCacheFooter)) >
-                g_logstorage_cache_max) {
-                dlt_log(LOG_ERR, "Max size of Logstorage Cache already used.");
-                return -1;
-            }
-
-            /* create cache */
-            config->cache = calloc(1,
-                                   config->file_size +
-                                   sizeof(DltLogStorageCacheFooter));
 
-            /* update current used cache size */
-            g_logstorage_cache_size = config->file_size +
-                sizeof(DltLogStorageCacheFooter);
+        /* check total logstorage cache size */
+        if ((g_logstorage_cache_size + cache_size +
+             sizeof(DltLogStorageCacheFooter)) >
+             g_logstorage_cache_max)
+        {
+            dlt_log(LOG_ERR, "Max size of Logstorage Cache already used.");
+            return -1;
         }
 
+        /* create cache */
+        config->cache = calloc(1, cache_size + sizeof(DltLogStorageCacheFooter));
+
         if (config->cache == NULL)
+        {
             dlt_log(LOG_CRIT,
                     "Cannot allocate memory for filter ring buffer\n");
+        }
+        else
+        {
+            /* update current used cache size */
+            g_logstorage_cache_size = cache_size + sizeof(DltLogStorageCacheFooter);
+        }
     }
 
     return 0;
@@ -1036,6 +937,8 @@ int dlt_logstorage_prepare_msg_cache(DltLogStorageFilterConfig *config,
  * Write the log message.
  *
  * @param config        DltLogStorageFilterConfig
+ * @param file_config   User configurations for log file
+ * @param dev_path      Storage device path
  * @param data1         header
  * @param size1         header size
  * @param data2         storage header
@@ -1045,6 +948,8 @@ int dlt_logstorage_prepare_msg_cache(DltLogStorageFilterConfig *config,
  * @return 0 on success, -1 on error
  */
 int dlt_logstorage_write_msg_cache(DltLogStorageFilterConfig *config,
+                                   DltLogStorageUserConfig *file_config,
+                                   char *dev_path,
                                    unsigned char *data1,
                                    int size1,
                                    unsigned char *data2,
@@ -1053,104 +958,95 @@ int dlt_logstorage_write_msg_cache(DltLogStorageFilterConfig *config,
                                    int size3)
 {
     DltLogStorageCacheFooter *footer = NULL;
-    DltLogStorageUserConfig *uconfig = NULL;
-    char *dev_path = NULL;
     int msg_size;
     int remain_cache_size;
     void *curr_write_addr = NULL;
     int ret = 0;
+    unsigned int cache_size;
 
     if ((config == NULL) || (data1 == NULL) || (size1 < 0) || (data2 == NULL) ||
-        (size2 < 0) || (data3 == NULL) || (size3 < 0) || (config->cache == NULL))
+        (size2 < 0) || (data3 == NULL) || (size3 < 0) || (config->cache == NULL) ||
+        (file_config == NULL) || (dev_path == NULL))
+    {
         return -1;
+    }
 
     if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                               DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0) {
-        footer = (DltLogStorageCacheFooter *)(config->cache +
-                                              config->specific_size);
-
-        if (footer == NULL) {
-            dlt_log(LOG_ERR, "Cannot retrieve cache footer. Address is NULL\n");
-            return -1;
-        }
-
-        msg_size = size1 + size2 + size3;
-        remain_cache_size = config->specific_size - footer->offset;
+                                     DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0)
+    {
+        cache_size = config->specific_size;
+    }
+    else
+    {
+        cache_size = config->file_size;
     }
-    else {
-        footer = (DltLogStorageCacheFooter *)(config->cache +
-                                              config->file_size);
-
-        if (footer == NULL) {
-            dlt_log(LOG_ERR, "Cannot retrieve cache footer. Address is NULL\n");
-            return -1;
-        }
 
-        msg_size = size1 + size2 + size3;
-        remain_cache_size = config->file_size - footer->offset;
+    footer = (DltLogStorageCacheFooter *)(config->cache + cache_size);
+    if (footer == NULL)
+    {
+        dlt_log(LOG_ERR, "Cannot retrieve cache footer. Address is NULL\n");
+        return -1;
     }
+    msg_size = size1 + size2 + size3;
+    remain_cache_size = cache_size - footer->offset;
 
-    if (msg_size <= remain_cache_size) { /* add at current position */
+    if (msg_size <= remain_cache_size) /* add at current position */
+    {
         curr_write_addr = (void *)(config->cache + footer->offset);
         footer->offset += msg_size;
+        if (footer->wrap_around_cnt < 1) {
+            footer->end_sync_offset = footer->offset;
+        }
     }
-    else if (msg_size > remain_cache_size)
+    else
     {
-        if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                   DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0) {
-            /*check for message size exceeds cache size for specific_size strategy */
-            if ((unsigned int)msg_size > config->specific_size) {
-                dlt_log(LOG_WARNING, "Message is larger than cache. Discard.\n");
-                return -1;
-            }
-        }
-        else if ((unsigned int)msg_size > config->file_size)
+        /*check for message size exceeds cache size for specific_size strategy */
+        if ((unsigned int) msg_size > cache_size)
         {
             dlt_log(LOG_WARNING, "Message is larger than cache. Discard.\n");
             return -1;
         }
 
-        /*sync to file for specific_size or file_size  */
-        if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                   DLT_LOGSTORAGE_SYNC_ON_FILE_SIZE) > 0) {
-            ret = config->dlt_logstorage_sync(config,
-                                              uconfig,
-                                              dev_path,
-                                              DLT_LOGSTORAGE_SYNC_ON_FILE_SIZE);
-
-            if (ret != 0) {
-                dlt_log(LOG_ERR, "dlt_logstorage_sync: Unable to sync.\n");
-                return -1;
-            }
-        }
-        else if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                        DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0)
-        {
-
-            ret = config->dlt_logstorage_sync(config,
-                                              uconfig,
-                                              dev_path,
-                                              DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE);
-
-            if (ret != 0) {
-                dlt_log(LOG_ERR, "dlt_logstorage_sync: Unable to sync.\n");
-                return -1;
-            }
-        }
-        else if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                        DLT_LOGSTORAGE_SYNC_ON_DEMAND) > 0)
-        {
-            config->pre_cache_sync = config->cur_cache_sync;
-            config->cur_cache_sync = 0;
-
-            if (config->pre_cache_sync == 0)
-                footer->last_sync_offset = 0;
-        }
+         /*sync to file for specific_size or file_size  */
+         if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
+                                                    DLT_LOGSTORAGE_SYNC_ON_FILE_SIZE) > 0)
+         {
+             ret = config->dlt_logstorage_sync(config,
+                                               file_config,
+                                               dev_path,
+                                               DLT_LOGSTORAGE_SYNC_ON_FILE_SIZE);
+             if (ret != 0)
+             {
+                 dlt_log(LOG_ERR,"dlt_logstorage_sync: Unable to sync.\n");
+                 return -1;
+             }
+         }
+         else if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
+                                                         DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0)
+         {
+
+             ret = config->dlt_logstorage_sync(config,
+                                               file_config,
+                                               dev_path,
+                                               DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE);
+             if (ret != 0)
+             {
+                 dlt_log(LOG_ERR,"dlt_logstorage_sync: Unable to sync.\n");
+                 return -1;
+             }
+         }
+         else if ((DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
+                                                         DLT_LOGSTORAGE_SYNC_ON_DEMAND) > 0) ||
+                  (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
+                                                         DLT_LOGSTORAGE_SYNC_ON_DAEMON_EXIT) > 0))
+         {
+             footer->wrap_around_cnt += 1;
+         }
 
         /* start writing from beginning */
+        footer->end_sync_offset = footer->offset;
         curr_write_addr = config->cache;
         footer->offset = msg_size;
-        footer->wrap_around_cnt += 1;
     }
 
     /* write data to cache */
@@ -1179,187 +1075,88 @@ int dlt_logstorage_sync_msg_cache(DltLogStorageFilterConfig *config,
                                   char *dev_path,
                                   int status)
 {
-    int ret = 0;
-    unsigned int remain_file_size = 0;
-    unsigned int count = 0;
+    unsigned int cache_size;
 
     DltLogStorageCacheFooter *footer = NULL;
 
-    if (config == NULL)
+    if ((config == NULL) || (file_config == NULL) || (dev_path == NULL))
+    {
         return -1;
+    }
 
     /* sync only, if given strategy is set */
-    if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync, status) > 0) {
-        if ((config->log == NULL) || (config->cache == NULL)) {
+    if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync, status) > 0)
+    {
+        if (config->cache == NULL)
+        {
             dlt_log(LOG_ERR,
-                    "Cannot copy cache to file. One of both is NULL\n");
+                    "Cannot copy cache to file. Cache is NULL\n");
             return -1;
         }
 
-        /* sync cache data to file for specific_size strategies */
-
-        if ((status == DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE)
-            || ((DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                        DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0)
-                && (status == DLT_LOGSTORAGE_SYNC_ON_DEMAND))
-            || ((DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                        DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0)
-                && (status == DLT_LOGSTORAGE_SYNC_ON_DAEMON_EXIT))) {
-            footer = (DltLogStorageCacheFooter *)(config->cache +
-                                                  config->specific_size);
-
-            if (footer == NULL) {
-                dlt_log(LOG_ERR, "Cannot retrieve cache information\n");
-                return -1;
-            }
-
-            count = footer->offset - footer->last_sync_offset;
-            /* write ring buffer into file */
-            ret = fwrite(config->cache + footer->last_sync_offset, count, 1, config->log);
-            dlt_logstorage_check_write_ret(config, ret);
-            config->current_write_file_offset += footer->offset - footer->last_sync_offset;
-            remain_file_size = config->file_size - config->current_write_file_offset;
-
-            if (status == DLT_LOGSTORAGE_SYNC_ON_DEMAND)
-                footer->last_sync_offset = footer->offset;
-            else
-                footer->last_sync_offset = 0;
-
-            if (remain_file_size < config->specific_size) {
-                config->current_write_file_offset = 0;
-                /* clean ring buffer and reset footer information */
-                memset(config->cache,
-                       0,
-                       config->specific_size + sizeof(DltLogStorageCacheFooter));
-
-                /* close the file, a new one will be created when prepare is
-                 * called again */
-
-                fclose(config->log);
-                config->log = NULL;
-            }
+        if (DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
+                                                   DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) > 0)
+        {
+            cache_size = config->specific_size;
         }
-        /* sync cache data to file for file size strategies*/
-
-        else if ((status == DLT_LOGSTORAGE_SYNC_ON_FILE_SIZE) ||
-                 (status == DLT_LOGSTORAGE_SYNC_ON_DAEMON_EXIT) ||
-                 ((DLT_OFFLINE_LOGSTORAGE_IS_STRATEGY_SET(config->sync,
-                                                          DLT_LOGSTORAGE_SYNC_ON_FILE_SIZE) > 0)
-                  && (status == DLT_LOGSTORAGE_SYNC_ON_DEMAND)))
+        else
         {
-            footer = (DltLogStorageCacheFooter *)(config->cache +
-                                                  config->file_size);
-
-            if (footer == NULL) {
-                dlt_log(LOG_ERR, "Cannot retrieve cache information\n");
-                return -1;
-            }
-
-            count = footer->offset - footer->last_sync_offset;
-            /* write cache to file */
-            ret = fwrite(config->cache + footer->last_sync_offset, count, 1, config->log);
-            dlt_logstorage_check_write_ret(config, ret);
-            config->current_write_file_offset += footer->offset - footer->last_sync_offset;
-            footer->last_sync_offset = footer->offset;
-
-            if ((status != DLT_LOGSTORAGE_SYNC_ON_DAEMON_EXIT)
-                && (status != DLT_LOGSTORAGE_SYNC_ON_DEMAND)) {
-                config->current_write_file_offset = 0;
-                /* clean ring buffer and reset footer information */
-                memset(config->cache,
-                       0,
-                       config->file_size + sizeof(DltLogStorageCacheFooter));
-
-                /* close the file, a new one will be created when prepare is
-                 * called again */
-                fclose(config->log);
-                config->log = NULL;
-            }
+            cache_size = config->file_size;
         }
-        /* sync cache to file for on_demand strategy  */
 
-        else if (status == DLT_LOGSTORAGE_SYNC_ON_DEMAND)
+        footer = (DltLogStorageCacheFooter *)(config->cache + cache_size);
+        if (footer == NULL)
         {
-            config->sync_from_start = 0;
-
-            if ((file_config == NULL) || (dev_path == NULL)) {
-                dlt_log(LOG_ERR, "Cannot retrieve user configuration or mount point\n");
-                return -1;
-            }
-
-            footer = (DltLogStorageCacheFooter *)(config->cache +
-                                                  config->file_size);
-
-            if (footer == NULL) {
-                dlt_log(LOG_ERR, "Cannot retrieve cache information\n");
-                return -1;
-            }
-
-            /* check for wrap around is 0 or cache is synced at least once
-             * in every wrap around */
-
-            if ((footer->wrap_around_cnt < 1) || (config->cur_cache_sync == 1)) {
-                ret = dlt_logstorage_sync_to_file(config,
-                                                  file_config,
-                                                  dev_path);
-
-                if (ret != 0)
-                    dlt_vlog(LOG_ERR, "%s: failed to sync data to file \n", __func__);
-            }
-            else {
-                remain_file_size = config->file_size - config->current_write_file_offset;
-
-                /* check for total bytes of data need to sync */
-                if (footer->offset >= footer->last_sync_offset)
-                    config->total_write_count = config->file_size;
-                else
-                    config->total_write_count = config->file_size - footer->last_sync_offset + footer->offset;
-
-                /* sync data to file if required sync data exceeds remaining file size */
-                if (config->total_write_count >= remain_file_size) {
-                    ret = dlt_logstorage_sync_create_new_file(config,
-                                                              file_config,
-                                                              dev_path,
-                                                              remain_file_size);
-
-                    if (ret != 0)
-                        dlt_vlog(LOG_ERR, "%s: failed to sync and open new file\n", __func__);
-
-                    /* sync remaining end of cache data to new file*/
-                    if (config->sync_from_start == 0) {
-                        ret = dlt_logstorage_sync_capable_data_to_file(config, 0);
-
-                        if (ret != 0)
-                            dlt_vlog(LOG_ERR, "%s: failed to sync capable data to file\n", __func__);
-                    }
-                }
-                /* sync data to file if required sync data less than remaining file size */
-                else {
-                    ret = dlt_logstorage_sync_capable_data_to_file(config, 1);
-
-                    if (ret != 0)
-                        dlt_vlog(LOG_ERR, "%s: failed to sync capable data\n", __func__);
-                }
+            dlt_log(LOG_ERR, "Cannot retrieve cache information\n");
+            return -1;
+        }
 
-                /* sync data to file from almost the begin of cache
-                 * if still data needs to sync */
+        /* sync cache data to file */
+        if (footer->wrap_around_cnt < 1)
+        {
+            /* Sync whole cache */
+            dlt_logstorage_sync_to_file(config, file_config, dev_path, footer,
+                                        footer->last_sync_offset, footer->offset);
 
-                if (config->total_write_count > 0) {
-                    count = footer->offset - footer->last_sync_offset;
-                    ret = fwrite(config->cache + footer->last_sync_offset,
-                                 count,
-                                 1,
-                                 config->log);
-                    dlt_logstorage_check_write_ret(config, ret);
-                    config->current_write_file_offset += count;
+        }
+        else if ((footer->wrap_around_cnt == 1) &&
+                 (footer->offset < footer->last_sync_offset))
+        {
+            /* sync (1) footer->last_sync_offset to footer->end_sync_offset,
+             * and (2) footer->last_sync_offset (= 0) to footer->offset */
+            dlt_logstorage_sync_to_file(config, file_config, dev_path, footer,
+                                        footer->last_sync_offset, footer->end_sync_offset);
+            footer->last_sync_offset = 0;
+            dlt_logstorage_sync_to_file(config, file_config, dev_path, footer,
+                                        footer->last_sync_offset, footer->offset);
+        }
+        else
+        {
+            /* sync (1) footer->offset + index to footer->end_sync_offset,
+             * and (2) footer->last_sync_offset (= 0) to footer->offset */
+            dlt_logstorage_sync_to_file(config, file_config, dev_path, footer,
+                                        footer->offset, footer->end_sync_offset);
+            footer->last_sync_offset = 0;
+            dlt_logstorage_sync_to_file(config, file_config, dev_path, footer,
+                                        footer->last_sync_offset, footer->offset);
+        }
 
-                    footer->last_sync_offset += count;
-                }
+        /* Initialize cache if needed */
+        if ((status == DLT_LOGSTORAGE_SYNC_ON_SPECIFIC_SIZE) ||
+            (status == DLT_LOGSTORAGE_SYNC_ON_FILE_SIZE))
+        {
+            /* clean ring buffer and reset footer information */
+            memset(config->cache, 0,
+                   cache_size + sizeof(DltLogStorageCacheFooter));
+        }
 
-                config->cur_cache_sync = 1;
-            }
+        if (status == DLT_LOGSTORAGE_SYNC_ON_FILE_SIZE)
+        {
+            /* Close log file */
+            fclose(config->log);
+            config->log = NULL;
+            config->current_write_file_offset = 0;
         }
     }
-
     return 0;
 }
diff --git a/src/offlinelogstorage/dlt_offline_logstorage_behavior.h b/src/offlinelogstorage/dlt_offline_logstorage_behavior.h
index 68de0ab..431741b 100644
--- a/src/offlinelogstorage/dlt_offline_logstorage_behavior.h
+++ b/src/offlinelogstorage/dlt_offline_logstorage_behavior.h
@@ -58,6 +58,8 @@ int dlt_logstorage_prepare_on_msg(DltLogStorageFilterConfig *config,
                                   char *dev_path,
                                   int log_msg_size);
 int dlt_logstorage_write_on_msg(DltLogStorageFilterConfig *config,
+                                DltLogStorageUserConfig *file_config,
+                                char *dev_path,
                                 unsigned char *data1,
                                 int size1,
                                 unsigned char *data2,
@@ -79,6 +81,8 @@ int dlt_logstorage_prepare_msg_cache(DltLogStorageFilterConfig *config,
                                      int log_msg_size);
 
 int dlt_logstorage_write_msg_cache(DltLogStorageFilterConfig *config,
+                                   DltLogStorageUserConfig *file_config,
+                                   char *dev_path,
                                    unsigned char *data1,
                                    int size1,
                                    unsigned char *data2,
diff --git a/src/offlinelogstorage/dlt_offline_logstorage_behavior_internal.h b/src/offlinelogstorage/dlt_offline_logstorage_behavior_internal.h
index 6ddf21e..a9d6d7d 100644
--- a/src/offlinelogstorage/dlt_offline_logstorage_behavior_internal.h
+++ b/src/offlinelogstorage/dlt_offline_logstorage_behavior_internal.h
@@ -72,23 +72,19 @@ int dlt_logstorage_open_log_file(DltLogStorageFilterConfig *config,
                                  char *dev_path,
                                  int msg_size);
 
-DLT_STATIC DltReturnValue dlt_logstorage_sync_create_new_file(
-    DltLogStorageFilterConfig *config,
-    DltLogStorageUserConfig *file_config,
-    char *dev_path,
-    unsigned int remain_file_size);
-
-DLT_STATIC DltReturnValue dlt_logstorage_sync_to_file(
-    DltLogStorageFilterConfig *config,
-    DltLogStorageUserConfig *file_config,
-    char *dev_path);
-
-DLT_STATIC DltReturnValue dlt_logstorage_sync_capable_data_to_file(
-    DltLogStorageFilterConfig *config,
-    int index_status);
+DLT_STATIC int dlt_logstorage_sync_to_file(DltLogStorageFilterConfig *config,
+                                           DltLogStorageUserConfig *file_config,
+                                           char *dev_path,
+                                           DltLogStorageCacheFooter *footer,
+                                           unsigned int start_offset,
+                                           unsigned int end_offset);
 
 DLT_STATIC int dlt_logstorage_find_dlt_header(void *ptr,
                                               unsigned int offset,
                                               unsigned int cnt);
 
+DLT_STATIC int dlt_logstorage_find_last_dlt_header(void *ptr,
+                                                   unsigned int offset,
+                                                   unsigned int cnt);
+
 #endif /* DLT_OFFLINELOGSTORAGE_BEHAVIOR_INTERNAL_H_ */
diff --git a/src/offlinelogstorage/dlt_offline_logstorage_internal.h b/src/offlinelogstorage/dlt_offline_logstorage_internal.h
index 9d1eaf7..f5c3fdf 100644
--- a/src/offlinelogstorage/dlt_offline_logstorage_internal.h
+++ b/src/offlinelogstorage/dlt_offline_logstorage_internal.h
@@ -51,6 +51,8 @@
 #define DLT_OFFLINE_LOGSTORAGE_INTERNAL_H
 
 DLT_STATIC int dlt_logstorage_list_destroy(DltLogStorageFilterList **list,
+                                           DltLogStorageUserConfig *uconfig,
+                                           char *dev_path,
                                            int reason);
 
 DLT_STATIC int dlt_logstorage_list_add_config(DltLogStorageFilterConfig *data,