[GDLT-84] Instead of calling the injection callback, store a pointer

to it and the required parameter data. Call the injection callback
only after releasing the semaphore lock. This way, calling DLT_LOG
will be possible even in the injection callback. Previously this
caused a deadlock because DLT_LOG would require another lock.

Signed-off-by: Christian Muck <christian.muck@bmw.de>

diff --git a/src/lib/dlt_user.c b/src/lib/dlt_user.c
index d1da51a..12d87cc 100755 (executable)
--- a/src/lib/dlt_user.c
+++ b/src/lib/dlt_user.c
@@ -2634,7 +2634,15 @@ int dlt_user_log_check_user_message(void)
     DltUserControlMsgInjection *usercontextinj;
     DltUserControlMsgLogState *userlogstate;
     unsigned char *userbuffer;
-    unsigned char *inject_buffer;
+
+    /* For delayed calling of injection callback, to avoid deadlock */
+    DltUserInjectionCallback   delayed_injection_callback;
+    unsigned char                              *delayed_inject_buffer = 0;
+    uint32_t                                   delayed_inject_data_length = 0;
+
+    /* Ensure that callback is null before searching for it */
+    delayed_injection_callback.injection_callback = 0;
+    delayed_injection_callback.service_id = 0;
 
     if (dlt_user.dlt_user_handle!=-1)
     {
@@ -2731,7 +2739,6 @@ int dlt_user_log_check_user_message(void)
 
                     usercontextinj = (DltUserControlMsgInjection*) (receiver->buf+sizeof(DltUserHeader));
                     userbuffer = (unsigned char*) (receiver->buf+sizeof(DltUserHeader)+sizeof(DltUserControlMsgInjection));
-                    inject_buffer = 0;
 
                     if (userbuffer!=0)
                     {
@@ -2752,33 +2759,18 @@ int dlt_user_log_check_user_message(void)
                                 if ((dlt_user.dlt_ll_ts[usercontextinj->log_level_pos].injection_table) &&
                                         (dlt_user.dlt_ll_ts[usercontextinj->log_level_pos].injection_table[i].service_id == usercontextinj->service_id))
                                 {
-                                    /* callback available, so prepare data, then call it */
-                                    inject_buffer = malloc(usercontextinj->data_length_inject);
-                                    if (inject_buffer!=0)
-                                    {
-                                        /* copy from receiver to inject_buffer */
-                                        memcpy(inject_buffer, userbuffer, usercontextinj->data_length_inject);
-
-                                        /* call callback */
-                                        if (dlt_user.dlt_ll_ts[usercontextinj->log_level_pos].injection_table[i].injection_callback!=0)
-                                        {
-                                            // printf("Got injection(%d), length=%d, '%s' \n", usercontext->service_id, usercontext->data_length_inject, inject_buffer);
-                                            dlt_user.dlt_ll_ts[usercontextinj->log_level_pos].injection_table[i].injection_callback(
-                                                usercontextinj->service_id, inject_buffer, usercontextinj->data_length_inject);
-                                        }
-
-                                        if (inject_buffer!=0)
-                                        {
-                                            free(inject_buffer);
-                                            inject_buffer = 0;
-                                        }
-                                    }
-                                    else
-                                    {
-                                       DLT_SEM_FREE();
-                                       return -1;
-                                    }
-
+                                       /* Prepare delayed injection callback call */
+                                                                       if (dlt_user.dlt_ll_ts[usercontextinj->log_level_pos].injection_table[i].injection_callback!=0)
+                                                                       {
+                                                                               delayed_injection_callback.injection_callback = dlt_user.dlt_ll_ts[usercontextinj->log_level_pos].injection_table[i].injection_callback;
+                                                                               delayed_injection_callback.service_id = usercontextinj->service_id;
+                                                                               delayed_inject_data_length = usercontextinj->data_length_inject;
+                                                                               delayed_inject_buffer = malloc(delayed_inject_data_length);
+                                                                               if(delayed_inject_buffer != 0) {
+                                                                                       memcpy(delayed_inject_buffer, userbuffer, delayed_inject_data_length);
+                                                                               }
+
+                                                                       }
                                     break;
                                 }
                             }
@@ -2786,6 +2778,12 @@ int dlt_user_log_check_user_message(void)
 
                         DLT_SEM_FREE();
 
+                        /* Delayed injection callback call */
+                        if(delayed_inject_buffer != 0 && delayed_injection_callback.injection_callback != 0) {
+                               delayed_injection_callback.injection_callback(delayed_injection_callback.service_id, delayed_inject_buffer, delayed_inject_data_length);
+                               free(delayed_inject_buffer);
+                        }
+
                         /* keep not read data in buffer */
                         if (dlt_receiver_remove(receiver,(sizeof(DltUserHeader)+sizeof(DltUserControlMsgInjection)+usercontextinj->data_length_inject))==-1)
                                                {