Fix build when zlib is not installed

Author: LocutusOfBorg

src/offlinelogstorage/dlt_offline_logstorage.h

@@ -53,7 +53,9 @@
 
 #include <search.h>
 #include <stdbool.h>
+#ifdef DLT_LOGSTORAGE_USE_GZIP
 #include <zlib.h>
+#endif
 #include "dlt_common.h"
 #include "dlt-daemon_cfg.h"
 #include "dlt_config_file_parser.h"
@@ -214,7 +216,9 @@ struct DltLogStorageFilterConfig
                                int status);
     FILE *log;                      /* current open log file */
     int fd;                         /* The file descriptor for the active log file */
+#ifdef DLT_LOGSTORAGE_USE_GZIP
     gzFile *gzlog;                  /* current open gz log file */
+#endif
     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 */

src/offlinelogstorage/dlt_offline_logstorage_behavior.c

@@ -1108,11 +1108,15 @@ int dlt_logstorage_prepare_on_msg(DltLogStorageFilterConfig *config,
                 if ((config->sync == DLT_LOGSTORAGE_SYNC_ON_MSG) ||
                     (config->sync == DLT_LOGSTORAGE_SYNC_UNSET)) {
                     if (config->gzip_compression == DLT_LOGSTORAGE_GZIP_ON) {
-                        if (fsync(fileno(config->gzlog)) != 0) {
+#ifdef DLT_LOGSTORAGE_USE_GZIP
+    			    if (fsync(fileno(config->gzlog)) != 0) {
                             if (errno != ENOSYS) {
                                 dlt_vlog(LOG_ERR, "%s: failed to sync gzip log file\n", __func__);
                             }
                         }
+#else
+                        dlt_vlog(LOG_ERR, "%s: dlt-daemon not compiled with logstorage gzip support\n", __func__);
+#endif
                     }
                     else {
                         if (fsync(fileno(config->log)) != 0) {