Allow multiple instances of dlt-daemon

 - Make dlt-daemon configurable to specify directory of fifos and port of dlt-daemon, this
   allows to run multiple instances of dlt-daemon at one node at the same time. This is useful
   in testing environment where simultanous tests should not interfere due to the same
   instance of dlt-daemon
 - dlt-daemon: add option -t <dir> to specify a directory where all fifos will be created
 - dlt-daemon: add option -p <port> to specify the port under which dlt-daemon can be connected
 - client-library: add environment variable DLT_PIPE_DIR to specify a non-default directory
   of fifos for logging applications
 - client-library: add environment variable DLT_DAEMON_TCP_PORT to specify the port under which
   dlt-daemon can be reached (especially when using dlt-receive)

Signed-off-by: Stefan Vacek <stefan.vacek@intel.com>
Signed-off-by: Lutz Helwing <lutz_helwing@mentor.com>

12 files changed, 205 insertions, 49 deletions

diff --git a/include/dlt/dlt_common.h b/include/dlt/dlt_common.h
index 10334ca..da9835c 100644
--- a/include/dlt/dlt_common.h
+++ b/include/dlt/dlt_common.h
@@ -76,6 +76,7 @@
 */
 
 #include <stdio.h>
+#include <linux/limits.h>
 
 #if !defined(_MSC_VER)
 #include <unistd.h>
@@ -186,12 +187,12 @@ enum {
 };
 
 /**
- * The standard TCP Port used for DLT daemon
+ * The standard TCP Port used for DLT daemon, can be overwritten via -p <port> when starting dlt-daemon
  */
 #define DLT_DAEMON_TCP_PORT 3490
 
 
-/* Initi value for file descritpor */
+/* Initial value for file descriptor */
 #define DLT_FD_INIT -1
 
 /* Minimum value for a file descriptor except the POSIX Standards: stdin=0, stdout=1, stderr=2 */
@@ -331,7 +332,11 @@ extern const char dltSerialHeader[DLT_ID_SIZE];
 extern char dltSerialHeaderChar[DLT_ID_SIZE];
 
 /**
+ * The common base-path of the dlt-daemon-fifo and application-generated fifos
+ */
+extern char dltFifoBaseDir[PATH_MAX + 1];
 
+/**
  * The type of a DLT ID (context id, application id, etc.)
  */
 typedef char ID4[DLT_ID_SIZE];
@@ -1287,6 +1292,12 @@ extern "C"
      */
     void dlt_check_envvar();
 
+    /**
+     * Create the specified path, recursive if necessary
+     * behaves like calling mkdir -p <dir> on the console
+     */
+    int dlt_mkdir_recursive(const char *dir);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/daemon/dlt-daemon.c b/src/daemon/dlt-daemon.c
index 0c70cde..5022da4 100644
--- a/src/daemon/dlt-daemon.c
+++ b/src/daemon/dlt-daemon.c
@@ -96,6 +96,14 @@ void usage()
     printf("  -d            Daemonize\n");
     printf("  -h            Usage\n");
     printf("  -c filename   DLT daemon configuration file (Default: " CONFIGURATION_FILES_DIR "/dlt.conf)\n");
+    printf("  -t directory  Directory for local fifo and user-pipes (Default: /tmp)\n");
+    printf("                (Applications wanting to connect to a daemon using a\n");
+    printf("                custom directory need to be started with the environment \n");
+    printf("                variable DLT_PIPE_DIR set appropriately)\n");
+    printf("  -p port       port to monitor for incoming requests (Default: 3490)\n");
+    printf("                (Applications wanting to connect to a daemon using a custom\n");
+    printf("                port need to be started with the environment variable\n");
+    printf("                DLT_DAEMON_TCP_PORT set appropriately)\n");
 } /* usage() */
 
 /**
@@ -114,9 +122,13 @@ int option_handling(DltDaemonLocal *daemon_local,int argc, char* argv[])
     /* Initialize flags */
     memset(daemon_local,0,sizeof(DltDaemonLocal));
 
+    /* default values */
+    daemon_local->flags.port = DLT_DAEMON_TCP_PORT;
+    strncpy(dltFifoBaseDir, "/tmp", NAME_MAX);
+
     opterr = 0;
 
-    while ((c = getopt (argc, argv, "hdc:")) != -1)
+    while ((c = getopt (argc, argv, "hdc:t:p:")) != -1)
     {
         switch (c)
         {
@@ -130,6 +142,21 @@ int option_handling(DltDaemonLocal *daemon_local,int argc, char* argv[])
             strncpy(daemon_local->flags.cvalue,optarg,NAME_MAX);
             break;
         }
+        case 't':
+        {
+            strncpy(dltFifoBaseDir, optarg, NAME_MAX);
+            break;
+        }
+        case 'p':
+        {
+            daemon_local->flags.port = atoi(optarg);
+            if (daemon_local->flags.port == 0)
+            {
+              fprintf (stderr, "Invalid port `%s' specified.\n", optarg);
+              return -1;
+            }
+            break;
+        }
         case 'h':
         {
             usage();
@@ -137,7 +164,7 @@ int option_handling(DltDaemonLocal *daemon_local,int argc, char* argv[])
         }
         case '?':
         {
-            if (optopt == 'c')
+            if (optopt == 'c' || optopt == 't' || optopt == 'p')
             {
                 fprintf (stderr, "Option -%c requires an argument.\n", optopt);
             }
@@ -161,6 +188,9 @@ int option_handling(DltDaemonLocal *daemon_local,int argc, char* argv[])
         } /* switch() */
     }
 
+    snprintf(daemon_local->flags.userPipesDir, NAME_MAX + 1, "%s/dltpipes", dltFifoBaseDir);
+    snprintf(daemon_local->flags.daemonFifoName, NAME_MAX + 1, "%s/dlt", dltFifoBaseDir);
+
     return 0;
 
  } /* option_handling() */
@@ -186,7 +216,7 @@ int option_file_parser(DltDaemonLocal *daemon_local)
 	daemon_local->flags.offlineTraceMaxSize = 0;
 	daemon_local->flags.loggingMode = DLT_LOG_TO_CONSOLE;
 	daemon_local->flags.loggingLevel = LOG_INFO;
-	strncpy(daemon_local->flags.loggingFilename, DLT_USER_DIR "/dlt.log",sizeof(daemon_local->flags.loggingFilename)-1);
+	snprintf(daemon_local->flags.loggingFilename, sizeof(daemon_local->flags.loggingFilename)-1, "%s/dlt.log", dltFifoBaseDir);
 	daemon_local->flags.loggingFilename[sizeof(daemon_local->flags.loggingFilename)-1]=0;
 	daemon_local->timeoutOnSend = 4;
 	daemon_local->RingbufferMinSize = DLT_DAEMON_RINGBUFFER_MIN_SIZE;
@@ -444,6 +474,14 @@ int main(int argc, char* argv[])
 
 	PRINT_FUNCTION_VERBOSE(daemon_local.flags.vflag);
 
+    /* Make sure the parent user directory is created */
+    if (dlt_mkdir_recursive(dltFifoBaseDir) != 0)
+    {
+      snprintf(str,DLT_DAEMON_TEXTBUFSIZE, "Base dir %s cannot be created!\n", dltFifoBaseDir);
+      dlt_log(LOG_ERR, str);
+      return -1;
+    }
+
     /* --- Daemon init phase 1 begin --- */
     if (dlt_daemon_local_init_p1(&daemon, &daemon_local, daemon_local.flags.vflag)==-1)
     {
@@ -671,20 +709,22 @@ int dlt_daemon_local_init_p1(DltDaemon *daemon, DltDaemonLocal *daemon_local, in
     }
 #endif
 
+    const char *tmpFifo = daemon_local->flags.userPipesDir;
+
     /* create dlt pipes directory */
-    ret=mkdir(DLT_USER_DIR, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IROTH  | S_IWOTH | S_ISVTX );
+    ret=mkdir(tmpFifo, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IROTH  | S_IWOTH | S_ISVTX );
     if (ret==-1 && errno != EEXIST)
     {
-        snprintf(str,DLT_DAEMON_TEXTBUFSIZE,"FIFO user dir %s cannot be created (%s)!\n", DLT_USER_DIR, strerror(errno));
+        snprintf(str,DLT_DAEMON_TEXTBUFSIZE,"FIFO user dir %s cannot be created (%s)!\n", tmpFifo, strerror(errno));
         dlt_log(LOG_WARNING, str);
         return -1;
     }
 
     // S_ISGID cannot be set by mkdir, let's reassign right bits
-    ret=chmod(DLT_USER_DIR, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH  | S_IWOTH | S_IXOTH | S_ISGID | S_ISVTX );
+    ret=chmod(tmpFifo, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH  | S_IWOTH | S_IXOTH | S_ISGID | S_ISVTX );
     if (ret==-1)
     {
-        snprintf(str,DLT_DAEMON_TEXTBUFSIZE,"FIFO user dir %s cannot be chmoded (%s)!\n", DLT_USER_DIR, strerror(errno));
+        snprintf(str,DLT_DAEMON_TEXTBUFSIZE,"FIFO user dir %s cannot be chmoded (%s)!\n", tmpFifo, strerror(errno));
         dlt_log(LOG_WARNING, str);
         return -1;
     }
@@ -846,27 +886,30 @@ int dlt_daemon_local_connection_init(DltDaemon *daemon, DltDaemonLocal *daemon_l
     umask(0);
 
     /* Try to delete existing pipe, ignore result of unlink */
-    unlink(DLT_USER_FIFO);
+    const char *tmpFifo = daemon_local->flags.daemonFifoName;
+    unlink(tmpFifo);
 
-    ret=mkfifo(DLT_USER_FIFO, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP );
+    ret=mkfifo(tmpFifo, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP );
     if (ret==-1)
     {
-        snprintf(str,DLT_DAEMON_TEXTBUFSIZE,"FIFO user %s cannot be created (%s)!\n",DLT_USER_FIFO, strerror(errno));
+        snprintf(str,DLT_DAEMON_TEXTBUFSIZE,"FIFO user %s cannot be created (%s)!\n",tmpFifo, strerror(errno));
         dlt_log(LOG_WARNING, str);
         return -1;
     } /* if */
 
-    daemon_local->fp = open(DLT_USER_FIFO, O_RDWR);
+    daemon_local->fp = open(tmpFifo, O_RDWR);
     if (daemon_local->fp==-1)
     {
-        snprintf(str,DLT_DAEMON_TEXTBUFSIZE,"FIFO user %s cannot be opened (%s)!\n",DLT_USER_FIFO, strerror(errno));
+        snprintf(str,DLT_DAEMON_TEXTBUFSIZE,"FIFO user %s cannot be opened (%s)!\n",tmpFifo, strerror(errno));
         dlt_log(LOG_WARNING, str);
         return -1;
     } /* if */
 
     /* create and open socket to receive incoming connections from client */
-    if(dlt_daemon_socket_open(&(daemon_local->sock)))
+    if(dlt_daemon_socket_open(&(daemon_local->sock), daemon_local->flags.port))
+    {
     	return -1;
+    }
 
     /* prepare usage of select(), add FIFO and receiving socket */
     FD_ZERO(&(daemon_local->master));
@@ -1044,7 +1087,7 @@ void dlt_daemon_local_cleanup(DltDaemon *daemon, DltDaemonLocal *daemon_local, i
     dlt_file_free(&(daemon_local->file),daemon_local->flags.vflag);
 
     /* Try to delete existing pipe, ignore result of unlink() */
-    unlink(DLT_USER_FIFO);
+    unlink(daemon_local->flags.daemonFifoName);
 
 #ifdef DLT_SHM_ENABLE
 	/* free shared memory */
@@ -1069,10 +1112,16 @@ void dlt_daemon_signal_handler(int sig)
         dlt_log(LOG_NOTICE, str);
 
         /* Try to delete existing pipe, ignore result of unlink() */
-        unlink(DLT_USER_FIFO);
+        char tmp[PATH_MAX + 1];
+        snprintf(tmp, PATH_MAX, "%s/dlt", dltFifoBaseDir);
+        tmp[PATH_MAX] = 0;
+        unlink(tmp);
 
         /* Try to delete lock file, ignore result of unlink() */
-        unlink(DLT_DAEMON_LOCK_FILE);
+        snprintf(tmp, PATH_MAX, "%s/%s", dltFifoBaseDir, DLT_DAEMON_LOCK_FILE);
+        tmp[PATH_MAX] = 0;
+        unlink(tmp);
+
 
 		/* Terminate program */
         exit(0);
@@ -1138,12 +1187,18 @@ void dlt_daemon_daemonize(int verbose)
     umask(DLT_DAEMON_UMASK);
 
     /* Change to known directory */
-    if(chdir(DLT_USER_DIR) < 0)
-        dlt_log(LOG_WARNING, "Failed to chdir to DLT_USER_DIR.\n");;
+    if(chdir(dltFifoBaseDir) < 0)
+    {
+        snprintf(str, DLT_DAEMON_TEXTBUFSIZE, "Failed to chdir to fifo-dir %s\n", dltFifoBaseDir);
+        dlt_log(LOG_WARNING, str);
+    }
 
-    /* Ensure single copy of daemon;
+    /* Ensure single copy of daemon; if started with same directory
        run only one instance at a time */
-    lfp=open(DLT_DAEMON_LOCK_FILE,O_RDWR|O_CREAT,DLT_DAEMON_LOCK_FILE_PERM);
+    char dlt_daemon_lock_file[PATH_MAX + 1];
+    snprintf(dlt_daemon_lock_file, PATH_MAX, "%s/%s", dltFifoBaseDir, DLT_DAEMON_LOCK_FILE);
+    dlt_daemon_lock_file[PATH_MAX] = 0;
+    lfp=open(dlt_daemon_lock_file,O_RDWR|O_CREAT,DLT_DAEMON_LOCK_FILE_PERM);
     if (lfp<0)
     {
     	dlt_log(LOG_CRIT, "Can't open lock file, exiting DLT daemon\n");
diff --git a/src/daemon/dlt-daemon.h b/src/daemon/dlt-daemon.h
index fee6767..8edeead 100644
--- a/src/daemon/dlt-daemon.h
+++ b/src/daemon/dlt-daemon.h
@@ -112,6 +112,9 @@ typedef struct
     char pathToECUSoftwareVersion[256]; /**< (String: Filename) The file from which to read the ECU version from. */
     int  sendTimezone; /**< (Boolean) Send Timezone perdiodically */
     int  offlineLogstorageMaxDevices; /**< (int) Maximum devices to be used as offline logstorage devices */
+    char userPipesDir[NAME_MAX + 1]; /**< (String: Directory) directory where dltpipes reside (Default: /tmp/dltpipes) */
+    char daemonFifoName[NAME_MAX + 1]; /**< (String: Filename) name of local fifo (Default: /tmp/dlt) */
+    unsigned int  port; /**< port number */
 } DltDaemonFlags;
 
 /**
diff --git a/src/daemon/dlt_daemon_common.c b/src/daemon/dlt_daemon_common.c
index 2064e94..af97b16 100644
--- a/src/daemon/dlt_daemon_common.c
+++ b/src/daemon/dlt_daemon_common.c
@@ -390,7 +390,7 @@ DltDaemonApplication* dlt_daemon_application_add(DltDaemon *daemon,char *apid,pi
         {
     		if ( close(application->user_handle) < 0 )
     		{
-    			snprintf(str,DLT_DAEMON_COMMON_TEXTBUFSIZE, "close() failed to %s, errno=%d (%s)!\n",filename,errno,strerror(errno)); /* errno 2: ENOENT - No such file or directory */
+    			snprintf(str,DLT_DAEMON_COMMON_TEXTBUFSIZE, "close() failed to %s/dltpipes/dlt%d, errno=%d (%s)!\n",dltFifoBaseDir,pid,errno,strerror(errno)); /* errno 2: ENOENT - No such file or directory */
     		    dlt_log(LOG_WARNING, str);
     		}
 
@@ -402,7 +402,7 @@ DltDaemonApplication* dlt_daemon_application_add(DltDaemon *daemon,char *apid,pi
     /* open user pipe only if it is not yet opened */
     if (application->user_handle==DLT_FD_INIT && pid!=0)
     {
-        snprintf(filename,DLT_DAEMON_COMMON_TEXTBUFSIZE,"%s/dlt%d",DLT_USER_DIR,pid);
+        snprintf(filename,DLT_DAEMON_COMMON_TEXTBUFSIZE,"%s/dltpipes/dlt%d",dltFifoBaseDir,pid);
 
         dlt_user_handle = open(filename, O_WRONLY|O_NONBLOCK);
         if ( dlt_user_handle < 0 )
diff --git a/src/daemon/dlt_daemon_socket.c b/src/daemon/dlt_daemon_socket.c
index 709868f..fa91485 100644
--- a/src/daemon/dlt_daemon_socket.c
+++ b/src/daemon/dlt_daemon_socket.c
@@ -63,7 +63,7 @@
 /** Global text output buffer, mainly used for creation of error/warning strings */
 static char str[DLT_DAEMON_TEXTBUFSIZE];
 
-int dlt_daemon_socket_open(int *sock)
+int dlt_daemon_socket_open(int *sock, unsigned int servPort)
 {
     int yes = 1;
     char portnumbuffer[33];
@@ -75,7 +75,7 @@ int dlt_daemon_socket_open(int *sock)
     hints.ai_socktype = SOCK_STREAM;
     hints.ai_flags = AI_PASSIVE; // use my IP address
 
-    sprintf(portnumbuffer, "%d", DLT_DAEMON_TCP_PORT);
+    snprintf(portnumbuffer, 32, "%d", servPort);
     if ((rv = getaddrinfo(NULL, portnumbuffer, &hints, &servinfo)) != 0) {
         snprintf(str, DLT_DAEMON_TEXTBUFSIZE, "getaddrinfo: %s\n", gai_strerror(rv));
         dlt_log(LOG_WARNING, str);
@@ -115,7 +115,7 @@ int dlt_daemon_socket_open(int *sock)
 
     freeaddrinfo(servinfo);
 
-    snprintf(str, DLT_DAEMON_TEXTBUFSIZE, "%s: Listening on port: %u\n", __FUNCTION__, DLT_DAEMON_TCP_PORT);
+    snprintf(str, DLT_DAEMON_TEXTBUFSIZE, "%s: Listening on port: %u\n", __FUNCTION__, servPort);
     dlt_log(LOG_INFO, str);
 
     // get socket buffer size
diff --git a/src/daemon/dlt_daemon_socket.h b/src/daemon/dlt_daemon_socket.h
index 5d4718c..cc8dfb5 100644
--- a/src/daemon/dlt_daemon_socket.h
+++ b/src/daemon/dlt_daemon_socket.h
@@ -62,7 +62,7 @@
 #include "dlt_common.h"
 #include "dlt_user.h"
 
-int dlt_daemon_socket_open(int *sock);
+int dlt_daemon_socket_open(int *sock, unsigned int servPort);
 int dlt_daemon_socket_close(int sock);
 
 int dlt_daemon_socket_get_send_qeue_max_size(int sock);
diff --git a/src/lib/dlt_client.c b/src/lib/dlt_client.c
index 2c9f46a..b77556d 100644
--- a/src/lib/dlt_client.c
+++ b/src/lib/dlt_client.c
@@ -131,7 +131,9 @@ int dlt_client_connect(DltClient *client, int verbose)
     char portnumbuffer[33];
     struct addrinfo hints, *servinfo, *p;
     int rv;
-
+    char *env_daemon_port;
+   /* the port may be specified by an environment variable, defaults to DLT_DAEMON_TCP_PORT */
+    unsigned short servPort = DLT_DAEMON_TCP_PORT;
     memset(&hints, 0, sizeof(hints));
     hints.ai_socktype = SOCK_STREAM;
 
@@ -140,9 +142,20 @@ int dlt_client_connect(DltClient *client, int verbose)
         return -1;
     }
 
+    /* the port may be specified by an environment variable */
+    env_daemon_port = getenv(DLT_CLIENT_ENV_DAEMON_TCP_PORT);
+    if (env_daemon_port != NULL)
+    {
+      servPort = atoi(env_daemon_port);
+    }
+    if (servPort == 0)
+    {
+      servPort = DLT_DAEMON_TCP_PORT;
+    }
+
     if (client->serial_mode==0)
     {
-        sprintf(portnumbuffer, "%d", DLT_DAEMON_TCP_PORT);
+        snprintf(portnumbuffer, 32, "%d", servPort);
         if ((rv = getaddrinfo(client->servIP, portnumbuffer, &hints, &servinfo)) != 0) {
             fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv));
             return -1;
diff --git a/src/lib/dlt_client_cfg.h b/src/lib/dlt_client_cfg.h
index c2592e6..45d1864 100644
--- a/src/lib/dlt_client_cfg.h
+++ b/src/lib/dlt_client_cfg.h
@@ -92,6 +92,9 @@
 #define DLT_CLIENT_INITIAL_BAUDRATE 0
 #endif
 
+/* Name of environment variable for specifying the daemon port */
+#define DLT_CLIENT_ENV_DAEMON_TCP_PORT "DLT_DAEMON_TCP_PORT"
+
 /************************/
 /* Don't change please! */
 /************************/
diff --git a/src/lib/dlt_user.c b/src/lib/dlt_user.c
index 9cf4070..f961bb5 100644
--- a/src/lib/dlt_user.c
+++ b/src/lib/dlt_user.c
@@ -64,6 +64,9 @@ static DltUser dlt_user;
 static int dlt_user_initialised = 0;
 static int dlt_user_freeing = 0;
 
+static char dlt_user_dir[NAME_MAX + 1];
+static char dlt_daemon_fifo[NAME_MAX + 1];
+
 static char str[DLT_USER_BUFFER_LENGTH];
 
 static sem_t dlt_mutex;
@@ -183,6 +186,9 @@ int dlt_init(void)
     /* check environment variables */
     dlt_check_envvar();
 
+    snprintf(dlt_user_dir, NAME_MAX, "%s/dltpipes", dltFifoBaseDir);
+    snprintf(dlt_daemon_fifo, NAME_MAX, "%s/dlt", dltFifoBaseDir);
+
     dlt_user.dlt_is_file = 0;
     dlt_user.overflow = 0;
     dlt_user.overflow_counter = 0;
@@ -191,10 +197,18 @@ int dlt_init(void)
 #endif
 
     /* create dlt pipes directory */
-    ret=mkdir(DLT_USER_DIR, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IROTH  | S_IWOTH | S_ISVTX );
+    /* Make sure the parent user directory is created */
+    if (dlt_mkdir_recursive(dltFifoBaseDir) != 0)
+    {
+      snprintf(str,DLT_USER_BUFFER_LENGTH, "Base dir %s cannot be created!\n", dltFifoBaseDir);
+      dlt_log(LOG_ERR, str);
+      return -1;
+    }
+
+    ret=mkdir(dlt_user_dir, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IROTH  | S_IWOTH | S_ISVTX );
     if (ret==-1 && errno != EEXIST)
     {
-        snprintf(str,DLT_USER_BUFFER_LENGTH,"FIFO user dir %s cannot be created!\n", DLT_USER_DIR);
+        snprintf(str,DLT_USER_BUFFER_LENGTH,"FIFO user dir %s cannot be created!\n", dlt_user_dir);
         dlt_log(LOG_ERR, str);
         return -1;
     }
@@ -203,25 +217,25 @@ int dlt_init(void)
     if(ret == 0)
     {
 		// S_ISGID cannot be set by mkdir, let's reassign right bits
-		ret=chmod(DLT_USER_DIR, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH  | S_IWOTH | S_IXOTH | S_ISGID | S_ISVTX );
+		ret=chmod(dlt_user_dir, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH  | S_IWOTH | S_IXOTH | S_ISGID | S_ISVTX );
 		if (ret==-1)
 		{
-			snprintf(str,DLT_USER_BUFFER_LENGTH,"FIFO user dir %s cannot be chmoded!\n", DLT_USER_DIR);
+			snprintf(str,DLT_USER_BUFFER_LENGTH,"FIFO user dir %s cannot be chmoded!\n", dlt_user_dir);
 			dlt_log(LOG_ERR, str);
 			return -1;
 		}
     }
 
     /* create and open DLT user FIFO */
-    snprintf(filename,DLT_USER_MAX_FILENAME_LENGTH,"%s/dlt%d",DLT_USER_DIR,getpid());
-
+    snprintf(filename,DLT_USER_MAX_FILENAME_LENGTH,"%s/dlt%d",dlt_user_dir,getpid());
+     
     /* Try to delete existing pipe, ignore result of unlink */
     unlink(filename);
 
     ret=mkfifo(filename, S_IRUSR | S_IWUSR | S_IWGRP | S_IRGRP );
     if (ret==-1)
     {
-        snprintf(str,DLT_USER_BUFFER_LENGTH,"Loging disabled, FIFO user %s cannot be created!\n",filename);
+        snprintf(str,DLT_USER_BUFFER_LENGTH,"Logging disabled, FIFO user %s cannot be created!\n",filename);
         dlt_log(LOG_WARNING, str);
         /* return 0; */ /* removed to prevent error, when FIFO already exists */
     }
@@ -230,7 +244,7 @@ int dlt_init(void)
     ret=chmod(filename, S_IRUSR | S_IWUSR | S_IWGRP | S_IRGRP );
     if (ret==-1)
     {
-        snprintf(str,DLT_USER_BUFFER_LENGTH,"FIFO user %s cannot be chmoded!\n", DLT_USER_DIR);
+        snprintf(str,DLT_USER_BUFFER_LENGTH,"FIFO user %s cannot be chmoded!\n", dlt_user_dir);
         dlt_log(LOG_WARNING, str);
         return -1;
     }
@@ -238,20 +252,20 @@ int dlt_init(void)
     dlt_user.dlt_user_handle = open(filename, O_RDWR | O_CLOEXEC);
     if (dlt_user.dlt_user_handle == DLT_FD_INIT)
     {
-        snprintf(str,DLT_USER_BUFFER_LENGTH,"Loging disabled, FIFO user %s cannot be opened!\n",filename);
+        snprintf(str,DLT_USER_BUFFER_LENGTH,"Logging disabled, FIFO user %s cannot be opened!\n",filename);
         dlt_log(LOG_WARNING, str);
         unlink(filename);
         return 0;
     }
 
     /* open DLT output FIFO */
-    dlt_user.dlt_log_handle = open(DLT_USER_FIFO, O_WRONLY | O_NONBLOCK | O_CLOEXEC );
+    dlt_user.dlt_log_handle = open(dlt_daemon_fifo, O_WRONLY | O_NONBLOCK | O_CLOEXEC );
     if (dlt_user.dlt_log_handle==-1)
     {
         /* This is a normal usecase. It is OK that the daemon (and thus the FIFO /tmp/dlt)
            starts later and some DLT users have already been started before.
            Thus it is OK if the FIFO can't be opened. */
-        snprintf(str,DLT_USER_BUFFER_LENGTH,"FIFO %s cannot be opened. Retrying later...\n",DLT_USER_FIFO);
+        snprintf(str,DLT_USER_BUFFER_LENGTH,"FIFO %s cannot be opened. Retrying later...\n",dlt_daemon_fifo);
         dlt_log(LOG_INFO, str);
         //return 0;
     }
@@ -612,7 +626,7 @@ int dlt_free(void)
 
     if (dlt_user.dlt_user_handle!=DLT_FD_INIT)
     {
-        snprintf(filename,DLT_USER_MAX_FILENAME_LENGTH,"%s/dlt%d",DLT_USER_DIR,getpid());
+        snprintf(filename,DLT_USER_MAX_FILENAME_LENGTH,"%s/dlt%d",dlt_user_dir,getpid());
 
         close(dlt_user.dlt_user_handle);
         dlt_user.dlt_user_handle=DLT_FD_INIT;
@@ -4252,7 +4266,7 @@ void dlt_user_log_reattach_to_daemon(void)
         dlt_user.dlt_log_handle=-1;
 
         /* try to open pipe to dlt daemon */
-        dlt_user.dlt_log_handle = open(DLT_USER_FIFO, O_WRONLY | O_NONBLOCK);
+        dlt_user.dlt_log_handle = open(dlt_daemon_fifo, O_WRONLY | O_NONBLOCK);
         if (dlt_user.dlt_log_handle > 0)
         {
             if (dlt_user_log_init(&handle,&log_new)==-1)
diff --git a/src/shared/dlt_common.c b/src/shared/dlt_common.c
index 98852fd..b0123b6 100644
--- a/src/shared/dlt_common.c
+++ b/src/shared/dlt_common.c
@@ -34,6 +34,9 @@
 #include <limits.h>   /* for NAME_MAX */
 #include <inttypes.h> /* for PRI formatting macro */
 
+#include <errno.h>
+#include <sys/stat.h> /* for mkdir() */
+
 #include "dlt_common.h"
 #include "dlt_common_cfg.h"
 
@@ -64,6 +67,7 @@ static char str[DLT_COMMON_BUFFER_LENGTH];
 
 const char dltSerialHeader[DLT_ID_SIZE] = { 'D','L','S',1 };
 char dltSerialHeaderChar[DLT_ID_SIZE] = { 'D','L','S',1 };
+char dltFifoBaseDir[PATH_MAX + 1] = "/tmp";
 
 /* internal logging parameters */
 static int logging_mode = DLT_LOG_TO_CONSOLE;
@@ -1983,6 +1987,12 @@ void dlt_log_set_filename(const char *filename)
 
 }
 
+void dlt_log_set_fifo_basedir(const char * env_pipe_dir)
+{
+    strncpy(dltFifoBaseDir, env_pipe_dir, PATH_MAX);
+    dltFifoBaseDir[PATH_MAX] = 0;
+}
+
 void dlt_log_init(int mode)
 {
     logging_mode = mode;
@@ -3723,5 +3733,48 @@ void dlt_check_envvar()
 		}
 	}
 
+    char* env_pipe_dir = getenv("DLT_PIPE_DIR");
+    if( env_pipe_dir != NULL )
+    {
+        dlt_log_set_fifo_basedir(env_pipe_dir);
+    }
+}
+
+int dlt_mkdir_recursive(const char *dir)
+{
+  int ret = 0;
+  char tmp[PATH_MAX+1];
+  char *p = NULL;
+  char *end = NULL;
+  size_t len;
+
+  strncpy(tmp, dir, PATH_MAX);
+  len = strlen(tmp);
+  if(tmp[len - 1] == '/')
+  {
+    tmp[len - 1] = 0;
+  }
+  end = tmp + len;
+
+  for(p = tmp + 1; ((*p) && (ret == 0)) || ((ret == -1 && errno == EEXIST) && (p != end)); p++)
+  {
+    if(*p == '/')
+    {
+      *p = 0;
+      ret = mkdir(tmp, S_IRWXU);
+      *p = '/';
+    }
+  }
+
+  if (ret == 0 || (ret == -1 && errno == EEXIST))
+  {
+    ret = mkdir(tmp, S_IRWXU);
+  }
+
+  if (ret == -1 && errno == EEXIST)
+  {
+    ret = 0;
+  }
 
+  return ret;
 }
diff --git a/src/shared/dlt_user_shared_cfg.h b/src/shared/dlt_user_shared_cfg.h
index fc74c0c..dc31e4d 100644
--- a/src/shared/dlt_user_shared_cfg.h
+++ b/src/shared/dlt_user_shared_cfg.h
@@ -74,12 +74,6 @@
 /* Changable */
 /*************/
 
-/* Directory, where the named pipes to the DLT daemon resides */
-#define DLT_USER_DIR  "/tmp/dltpipes"
-
-/* Name of named pipe to DLT daemon */
-#define DLT_USER_FIFO "/tmp/dlt"
-
 /************************/
 /* Don't change please! */
 /************************/
diff --git a/tests/gtest_dlt_daemon_common.cpp b/tests/gtest_dlt_daemon_common.cpp
index 8049965..58cc77e 100644
--- a/tests/gtest_dlt_daemon_common.cpp
+++ b/tests/gtest_dlt_daemon_common.cpp
@@ -44,6 +44,16 @@ extern "C" {
 #include "dlt_offline_trace.h"
 }
 
+#ifndef DLT_USER_DIR
+#define DLT_USER_DIR  "/tmp/dltpipes"
+#endif
+
+/* Name of named pipe to DLT daemon */
+#ifndef DLT_USER_FIFO
+#define DLT_USER_FIFO "/tmp/dlt"
+#endif
+
+
 /* Begin Method:dlt_daemon_common::dlt_daemon_application_add */
 TEST(t_dlt_daemon_application_add, normal)
 {