IPC: Unix socket added (#43)

* IPC: Unix socket added

The user can select either FIFO or UNIX socket as IPC between user library and daemon through  CMakelist option.
Socket path configurable for both FIFO and Unix Socket now configurable in CMake

Signed-off-by: Christoph Lipka <clipka@de.adit-jv.com>
Signed-off-by: ManikandanC <Manikandan.Chockalingam@in.bosch.com>

1 files changed, 208 insertions, 113 deletions

diff --git a/src/lib/dlt_user.c b/src/lib/dlt_user.c
index 8d1aec1..70fb564 100644
--- a/src/lib/dlt_user.c
+++ b/src/lib/dlt_user.c
@@ -55,7 +55,10 @@
 #include <unistd.h>
 
 #include <stdbool.h>
-
+#ifdef DLT_USE_UNIX_SOCKET_IPC
+#include <sys/un.h>
+#include <sys/socket.h>
+#endif
 
 #include "dlt_user.h"
 #include "dlt_common.h"
@@ -79,8 +82,10 @@ static DltUser dlt_user;
 static bool dlt_user_initialised = false;
 static int dlt_user_freeing = 0;
 
+#ifndef DLT_USE_UNIX_SOCKET_IPC
 static char dlt_user_dir[NAME_MAX + 1];
 static char dlt_daemon_fifo[NAME_MAX + 1];
+#endif
 
 static char str[DLT_USER_BUFFER_LENGTH];
 
@@ -185,50 +190,79 @@ DltReturnValue dlt_user_check_library_version(const char *user_major_version,con
     return DLT_RETURN_OK;
 }
 
-DltReturnValue dlt_init(void)
+#ifdef DLT_USE_UNIX_SOCKET_IPC
+static DltReturnValue dlt_initialize_socket_connection(void)
 {
-    char filename[DLT_USER_MAX_FILENAME_LENGTH];
-    int ret;
+    struct sockaddr_un remote;
+    int status = 0;
+    char dltSockBaseDir[DLT_IPC_PATH_MAX];
 
-    // process is exiting. Do not allocate new resources.
-    if (dlt_user_freeing != 0)
+    DLT_SEM_LOCK();
+    int sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
+
+    if (sockfd == DLT_FD_INIT)
     {
-        // return negative value, to stop the current log
+        dlt_log(LOG_CRIT, "Failed to create socket\n");
+	DLT_SEM_FREE();
         return DLT_RETURN_ERROR;
     }
 
-    // WARNING: multithread unsafe !
-    // Another thread will check that dlt_user_initialised != 0, but the lib is not initialised !
-    dlt_user_initialised = true;
-
-    /* Initialize common part of dlt_init()/dlt_init_file() */
-    if (dlt_init_common() == DLT_RETURN_ERROR)
+    status = fcntl(sockfd, F_SETFL, fcntl(sockfd, F_GETFL, 0) | O_NONBLOCK);
+    if (status == -1)
     {
-        dlt_user_initialised = false;
+        dlt_vlog(LOG_INFO,
+                "Socket %s/dlt cannot be changed to NON BLOCK\n",
+                DLT_USER_IPC_PATH);
         return DLT_RETURN_ERROR;
     }
 
-    /* check environment variables */
-    dlt_check_envvar();
-
-    snprintf(dlt_user_dir, NAME_MAX, "%s/dltpipes", dltFifoBaseDir);
-    snprintf(dlt_daemon_fifo, NAME_MAX, "%s/dlt", dltFifoBaseDir);
+    remote.sun_family = AF_UNIX;
+    snprintf(dltSockBaseDir, DLT_IPC_PATH_MAX, "%s/dlt", DLT_USER_IPC_PATH);
+    strncpy(remote.sun_path, dltSockBaseDir, sizeof(dltSockBaseDir));
 
-    dlt_user.dlt_is_file = 0;
-    dlt_user.overflow = 0;
-    dlt_user.overflow_counter = 0;
-#ifdef DLT_SHM_ENABLE
-    memset(&(dlt_user.dlt_shm),0,sizeof(DltShm));
-#endif
+    if (strlen(DLT_USER_IPC_PATH) > DLT_IPC_PATH_MAX)
+    {
+        dlt_vlog(LOG_INFO,
+                 "Provided path too long...trimming it to path[%s]\n",
+                 dltSockBaseDir);
+    }
 
-    /* create dlt pipes directory */
-    /* Make sure the parent user directory is created */
-    if (dlt_mkdir_recursive(dltFifoBaseDir) != 0)
+    if (connect(sockfd, (struct sockaddr*) &remote, sizeof(remote)) == -1)
+    {
+        if (dlt_user.connection_state != DLT_USER_RETRY_CONNECT)
+        {
+            dlt_vlog(LOG_INFO,
+                     "Socket %s cannot be opened. Retrying later...\n",
+                     dltSockBaseDir);
+            dlt_user.connection_state = DLT_USER_RETRY_CONNECT;
+        }
+    }
+    else
     {
-      dlt_vnlog(LOG_ERR,DLT_USER_BUFFER_LENGTH, "Base dir %s cannot be created!\n", dltFifoBaseDir);
-      return DLT_RETURN_ERROR;
+        dlt_user.dlt_log_handle = sockfd;
+        dlt_user.connection_state = DLT_USER_CONNECTED;
+
+        if (dlt_receiver_init(&(dlt_user.receiver),
+                              sockfd,
+                              DLT_USER_RCVBUF_MAX_SIZE) == DLT_RETURN_ERROR)
+        {
+            dlt_user_initialised = false;
+            DLT_SEM_FREE();
+            return DLT_RETURN_ERROR;
+        }
     }
+    DLT_SEM_FREE();
+
+    return DLT_RETURN_OK;
+}
+#else /* setup fifo*/
+static DltReturnValue dlt_initialize_fifo_connection(void)
+{
+    char filename[DLT_USER_MAX_FILENAME_LENGTH];
+    int ret;
 
+    snprintf(dlt_user_dir, NAME_MAX, "%s/dltpipes", dltFifoBaseDir);
+    snprintf(dlt_daemon_fifo, NAME_MAX, "%s/dlt", dltFifoBaseDir);
     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)
     {
@@ -250,7 +284,7 @@ DltReturnValue dlt_init(void)
 
     /* create and open DLT user FIFO */
     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);
 
@@ -281,33 +315,77 @@ DltReturnValue dlt_init(void)
     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. */
-        dlt_vnlog(LOG_INFO, DLT_USER_BUFFER_LENGTH, "FIFO %s cannot be opened. Retrying later...\n",dlt_daemon_fifo);
-        //return DLT_RETURN_OK;
-    }
-    else
-    {
-#ifdef DLT_SHM_ENABLE
-        /* init shared memory */
-        if (dlt_shm_init_client(&(dlt_user.dlt_shm),DLT_SHM_KEY) < 0)
+    
+        if (dlt_user.connection_state != DLT_USER_RETRY_CONNECT)
         {
             /* 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. */
-            dlt_vnlog(LOG_INFO, DLT_USER_BUFFER_LENGTH, "Shared memory %d cannot be created. Retrying later...\n", DLT_SHM_KEY);
-            //return DLT_RETURN_OK;
+            dlt_vnlog(LOG_INFO, DLT_USER_BUFFER_LENGTH, "FIFO %s cannot be opened. Retrying later...\n",dlt_daemon_fifo);
+            dlt_user.connection_state = DLT_USER_RETRY_CONNECT;
         }
+        //return DLT_RETURN_OK;
+    }
+
+    return DLT_RETURN_OK;
+}
 #endif
+
+DltReturnValue dlt_init(void)
+{
+    // process is exiting. Do not allocate new resources.
+    if (dlt_user_freeing != 0)
+    {
+        // return negative value, to stop the current log
+        return DLT_RETURN_ERROR;
     }
 
+    // WARNING: multithread unsafe !
+    // Another thread will check that dlt_user_initialised != 0, but the lib is not initialised !
+    dlt_user_initialised = true;
+
+    /* Initialize common part of dlt_init()/dlt_init_file() */
+    if (dlt_init_common() == DLT_RETURN_ERROR)
+    {
+        dlt_user_initialised = false;
+        return DLT_RETURN_ERROR;
+    }
+    strncpy(dltFifoBaseDir, DLT_USER_IPC_PATH, sizeof(DLT_USER_IPC_PATH));
+    /* check environment variables */
+    dlt_check_envvar();
 
+    dlt_user.dlt_is_file = 0;
+    dlt_user.overflow = 0;
+    dlt_user.overflow_counter = 0;
+#ifdef DLT_SHM_ENABLE
+    memset(&(dlt_user.dlt_shm),0,sizeof(DltShm));
+    /* init shared memory */
+    if (dlt_shm_init_client(&(dlt_user.dlt_shm),DLT_SHM_KEY) < 0)
+    {
+        snprintf(str,DLT_USER_BUFFER_LENGTH,"Logging disabled, Shared memory %d cannot be created!\n",DLT_SHM_KEY);
+        dlt_log(LOG_WARNING, str);
+        //return 0;
+    }
+#elif defined DLT_USE_UNIX_SOCKET_IPC
+    if (dlt_initialize_socket_connection() != DLT_RETURN_OK)
+    {
+        // We could connect to the pipe, but not to the socket, which is normally
+        // open before by the DLT daemon => bad failure => return error code
+        // in case application is started before daemon, it is expected behaviour
+        return DLT_RETURN_ERROR;
+    }
+#else /* FIFO connection */
+    if (dlt_initialize_fifo_connection() != DLT_RETURN_OK)
+    {
+        return DLT_RETURN_ERROR;
+    }
+    dlt_user.connection_state = DLT_USER_CONNECTED;
     if (dlt_receiver_init(&(dlt_user.receiver),dlt_user.dlt_user_handle, DLT_USER_RCVBUF_MAX_SIZE) == DLT_RETURN_ERROR)
     {
         dlt_user_initialised = false;
         return DLT_RETURN_ERROR;
     }
+#endif
 
     /* These will be lazy initialized only when needed */
     dlt_user.dlt_segmented_queue_read_handle = -1;
@@ -676,7 +754,9 @@ int dlt_user_atexit_blow_out_user_buffer(void){
 DltReturnValue dlt_free(void)
 {
     uint32_t i;
+#ifndef DLT_USE_UNIX_SOCKET_IPC
     char filename[DLT_USER_MAX_FILENAME_LENGTH];
+#endif
 
     if( dlt_user_freeing != 0 )
         // resources are already being freed. Do nothing and return.
@@ -694,15 +774,15 @@ DltReturnValue dlt_free(void)
 
     dlt_stop_threads();
 
+#ifndef DLT_USE_UNIX_SOCKET_IPC
     if (dlt_user.dlt_user_handle!=DLT_FD_INIT)
     {
-        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;
-
+        snprintf(filename,DLT_USER_MAX_FILENAME_LENGTH,"%s/dlt%d",dlt_user_dir,getpid());
         unlink(filename);
     }
+#endif
 
 #ifdef DLT_SHM_ENABLE
     /* free shared memory */
@@ -1347,7 +1427,6 @@ DltReturnValue dlt_forward_msg(void *msgdata,size_t size)
             }
         }
 
-        /* log to FIFO */
         ret = dlt_user_log_out3(dlt_user.dlt_log_handle,
                                 &(userheader), sizeof(DltUserHeader),
                                 msgdata, size, 0, 0);
@@ -3599,13 +3678,11 @@ DltReturnValue dlt_user_log_send_log(DltContextData *log, int mtype)
                 dlt_shm_push(&dlt_user.dlt_shm,msg.headerbuffer+sizeof(DltStorageHeader), msg.headersize-sizeof(DltStorageHeader),
                                             log->buffer, log->size, 0, 0);
 
-            /* log to FIFO */
             ret = dlt_user_log_out3(dlt_user.dlt_log_handle,
                                     &(userheader), sizeof(DltUserHeader),
                                     0, 0,
                                     0, 0);
 #else
-            /* log to FIFO */
 #ifdef DLT_TEST_ENABLE
             if(dlt_user.corrupt_user_header) {
                 userheader.pattern[0]=0xff;
@@ -3669,6 +3746,7 @@ DltReturnValue dlt_user_log_send_log(DltContextData *log, int mtype)
                 /* handle not open or pipe error */
                 close(dlt_user.dlt_log_handle);
                 dlt_user.dlt_log_handle = -1;
+                dlt_user.connection_state = DLT_USER_RETRY_CONNECT;
 
     #ifdef DLT_SHM_ENABLE
                 /* free shared memory */
@@ -3738,7 +3816,6 @@ DltReturnValue dlt_user_log_send_register_application(void)
         return DLT_RETURN_OK;
     }
 
-    /* log to FIFO */
     ret = dlt_user_log_out3(dlt_user.dlt_log_handle,
                     &(userheader), sizeof(DltUserHeader),
                     &(usercontext), sizeof(DltUserControlMsgRegisterApplication),
@@ -3795,10 +3872,10 @@ DltReturnValue dlt_user_log_send_unregister_application(void)
         return DLT_RETURN_OK;
     }
 
-    /* log to FIFO */
     return dlt_user_log_out2(dlt_user.dlt_log_handle,
-                    &(userheader), sizeof(DltUserHeader),
-                    &(usercontext), sizeof(DltUserControlMsgUnregisterApplication));
+                            &(userheader), sizeof(DltUserHeader),
+                            &(usercontext), sizeof(DltUserControlMsgUnregisterApplication));
+
 }
 
 DltReturnValue dlt_user_log_send_register_context(DltContextData *log)
@@ -3851,7 +3928,6 @@ DltReturnValue dlt_user_log_send_register_context(DltContextData *log)
         return DLT_RETURN_OK;
     }
 
-    /* log to FIFO */
     if (dlt_user.appID[0]!='\0')
     {
         ret = dlt_user_log_out3(dlt_user.dlt_log_handle, &(userheader), sizeof(DltUserHeader), &(usercontext), sizeof(DltUserControlMsgRegisterContext),log->context_description,usercontext.description_length);
@@ -3921,10 +3997,11 @@ DltReturnValue dlt_user_log_send_unregister_context(DltContextData *log)
         return DLT_RETURN_OK;
     }
 
-    /* log to FIFO */
     return dlt_user_log_out2(dlt_user.dlt_log_handle,
-                    &(userheader), sizeof(DltUserHeader),
-                    &(usercontext), sizeof(DltUserControlMsgUnregisterContext));
+                            &(userheader),
+                            sizeof(DltUserHeader),
+                            &(usercontext),
+                            sizeof(DltUserControlMsgUnregisterContext));
 }
 
 DltReturnValue dlt_send_app_ll_ts_limit(const char *appid, DltLogLevelType loglevel, DltTraceStatusType tracestatus)
@@ -3979,10 +4056,10 @@ DltReturnValue dlt_send_app_ll_ts_limit(const char *appid, DltLogLevelType logle
         return DLT_RETURN_OK;
     }
 
-    /* log to FIFO */
     return dlt_user_log_out2(dlt_user.dlt_log_handle,
-                    &(userheader), sizeof(DltUserHeader),
-                    &(usercontext), sizeof(DltUserControlMsgAppLogLevelTraceStatus));
+                            &(userheader), sizeof(DltUserHeader),
+                            &(usercontext), sizeof(DltUserControlMsgAppLogLevelTraceStatus));
+
 }
 
 DltReturnValue dlt_user_log_send_log_mode(DltUserLogMode mode)
@@ -4010,7 +4087,6 @@ DltReturnValue dlt_user_log_send_log_mode(DltUserLogMode mode)
         return DLT_RETURN_OK;
     }
 
-    /* log to FIFO */
     return dlt_user_log_out2(dlt_user.dlt_log_handle,
                     &(userheader), sizeof(DltUserHeader),
                     &(logmode), sizeof(DltUserControlMsgLogMode));
@@ -4083,6 +4159,7 @@ DltReturnValue dlt_user_log_check_user_message(void)
     int leave_while=0;
 
     uint32_t i;
+    int fd;
 
     DltUserHeader *userheader;
     DltReceiver *receiver = &(dlt_user.receiver);
@@ -4103,7 +4180,13 @@ DltReturnValue dlt_user_log_check_user_message(void)
     delayed_injection_callback.service_id = 0;
     delayed_log_level_changed_callback.log_level_changed_callback = 0;
 
-    if (dlt_user.dlt_user_handle!=DLT_FD_INIT)
+#ifdef DLT_USE_UNIX_SOCKET_IPC
+    fd = dlt_user.dlt_log_handle;
+#else
+    fd = dlt_user.dlt_user_handle;
+#endif
+
+    if (fd != DLT_FD_INIT)
     {
         while (1)
         {
@@ -4377,10 +4460,8 @@ DltReturnValue dlt_user_log_resend_buffer(void)
 #ifdef DLT_SHM_ENABLE
             dlt_shm_push(&dlt_user.dlt_shm, dlt_user.resend_buffer+sizeof(DltUserHeader), size-sizeof(DltUserHeader), 0, 0, 0, 0);
 
-            /* log to FIFO */
             ret = dlt_user_log_out3(dlt_user.dlt_log_handle, dlt_user.resend_buffer,sizeof(DltUserHeader), 0, 0, 0, 0);
 #else
-            /* log to FIFO */
             ret = dlt_user_log_out3(dlt_user.dlt_log_handle, dlt_user.resend_buffer,size, 0, 0, 0, 0);
 #endif
 
@@ -4413,72 +4494,87 @@ void dlt_user_log_reattach_to_daemon(void)
     {
         dlt_user.dlt_log_handle=-1;
 
+#ifdef DLT_USE_UNIX_SOCKET_IPC
+        /* try to open connection to dlt daemon */
+        dlt_initialize_socket_connection();
+        if (dlt_user.connection_state != DLT_USER_CONNECTED)
+        {
+            /* return if not connected */
+            return;
+        }
+
+#else
         /* try to open pipe to dlt daemon */
-        dlt_user.dlt_log_handle = open(dlt_daemon_fifo, O_WRONLY | O_NONBLOCK);
-        if (dlt_user.dlt_log_handle > 0)
+        int fd = open(dlt_daemon_fifo, O_WRONLY | O_NONBLOCK);
+
+        if (fd < 0)
         {
-            if (dlt_user_log_init(&handle,&log_new) < DLT_RETURN_OK)
-            {
-                return;
-            }
+            return;
+        }
+
+        dlt_user.dlt_log_handle = fd;
+#endif
+        if (dlt_user_log_init(&handle,&log_new) < DLT_RETURN_OK)
+        {
+            return;
+        }
 
 #ifdef DLT_SHM_ENABLE
-            /* init shared memory */
-            if (dlt_shm_init_client(&dlt_user.dlt_shm,DLT_SHM_KEY) < 0)
-            {
-                dlt_vnlog(LOG_WARNING, DLT_USER_BUFFER_LENGTH, "Loging disabled, Shared memory %d cannot be created!\n", DLT_SHM_KEY);
-                //return DLT_RETURN_OK;
-            }
+        /* init shared memory */
+        if (dlt_shm_init_client(&dlt_user.dlt_shm,DLT_SHM_KEY) < 0)
+        {
+            dlt_vnlog(LOG_WARNING, DLT_USER_BUFFER_LENGTH, "Loging disabled, Shared memory %d cannot be created!\n", DLT_SHM_KEY);
+            //return DLT_RETURN_OK;
+        }
 #endif
 
-            dlt_log(LOG_NOTICE, "Logging (re-)enabled!\n");
+        dlt_log(LOG_NOTICE, "Logging (re-)enabled!\n");
 
-            /* Re-register application */
-            if (dlt_user_log_send_register_application() < DLT_RETURN_ERROR)
-            {
-                return;
-            }
+        /* Re-register application */
+        if (dlt_user_log_send_register_application() < DLT_RETURN_ERROR)
+        {
+            return;
+        }
 
-            DLT_SEM_LOCK();
+        DLT_SEM_LOCK();
 
-            /* Re-register all stored contexts */
-            for (num=0; num<dlt_user.dlt_ll_ts_num_entries; num++)
+        /* Re-register all stored contexts */
+        for (num=0; num<dlt_user.dlt_ll_ts_num_entries; num++)
+        {
+            /* Re-register stored context */
+            if ((dlt_user.appID[0]!='\0') && (dlt_user.dlt_ll_ts) && (dlt_user.dlt_ll_ts[num].contextID[0]!='\0'))
             {
-                /* Re-register stored context */
-                if ((dlt_user.appID[0]!='\0') && (dlt_user.dlt_ll_ts) && (dlt_user.dlt_ll_ts[num].contextID[0]!='\0'))
-                {
-                    //dlt_set_id(log_new.appID, dlt_user.appID);
-                    dlt_set_id(handle.contextID, dlt_user.dlt_ll_ts[num].contextID);
-                    handle.log_level_pos = num;
-                    log_new.context_description = dlt_user.dlt_ll_ts[num].context_description;
+                //dlt_set_id(log_new.appID, dlt_user.appID);
+                dlt_set_id(handle.contextID, dlt_user.dlt_ll_ts[num].contextID);
+                handle.log_level_pos = num;
+                log_new.context_description = dlt_user.dlt_ll_ts[num].context_description;
 
-                    // Release the mutex for sending context registration:
-                    // function  dlt_user_log_send_register_context() can take the mutex to write to the DLT buffer. => dead lock
-                    DLT_SEM_FREE();
+                // Release the mutex for sending context registration:
+                // function  dlt_user_log_send_register_context() can take the mutex to write to the DLT buffer. => dead lock
+                DLT_SEM_FREE();
 
-                    log_new.log_level = DLT_USER_LOG_LEVEL_NOT_SET;
-                    log_new.trace_status = DLT_USER_TRACE_STATUS_NOT_SET;
+                log_new.log_level = DLT_USER_LOG_LEVEL_NOT_SET;
+                log_new.trace_status = DLT_USER_TRACE_STATUS_NOT_SET;
 
-                    if (dlt_user_log_send_register_context(&log_new) < DLT_RETURN_ERROR)
-                    {
-                        return;
-                    }
+                if (dlt_user_log_send_register_context(&log_new) < DLT_RETURN_ERROR)
+                {
+                    return;
+                }
 
-                    reregistered=1;
+                reregistered=1;
 
-                    // Lock again the mutex
-                    // it is necessary in the for(;;) test, in order to have coherent dlt_user data all over the critical section.
-                    DLT_SEM_LOCK();
+                // Lock again the mutex
+                // it is necessary in the for(;;) test, in order to have coherent dlt_user data all over the critical section.
+                DLT_SEM_LOCK();
 
-                }
             }
+        }
 
-            DLT_SEM_FREE();
+        DLT_SEM_FREE();
 
-            if (reregistered==1)
-            {
-                dlt_user_log_resend_buffer();
-            }
+        if (reregistered==1)
+        {
+            dlt_user_log_resend_buffer();
         }
     }
 }
@@ -4503,7 +4599,6 @@ DltReturnValue dlt_user_log_send_overflow(void)
     userpayload.overflow_counter = dlt_user.overflow_counter;
     dlt_set_id(userpayload.apid,dlt_user.appID);
 
-    /* log to FIFO */
     return dlt_user_log_out2(dlt_user.dlt_log_handle,
                     &(userheader), sizeof(DltUserHeader),
                     &(userpayload), sizeof(DltUserControlMsgBufferOverflow));