Proper setup and error checking of pthread_create

* Replace all start_XXX functions with one start_thread
* Don't make pthread_t static
* Don't use pthread_attr_t. Simply pass NULL
* Bail out  when pthread_create() fails
* Check if MAX_THREADS gets exceeded

Signed-off-by: Sebastian Kloska <sebastian.kloska@daimler.com>

8 files changed, 49 insertions, 77 deletions

diff --git a/src/system/dlt-system-filetransfer.c b/src/system/dlt-system-filetransfer.c
index 9091b1a..85aa380 100644
--- a/src/system/dlt-system-filetransfer.c
+++ b/src/system/dlt-system-filetransfer.c
@@ -765,12 +765,3 @@ void filetransfer_thread(void *v_conf)
         sleep(conf->Filetransfer.TimeDelay);
     }
 }
-
-void start_filetransfer(DltSystemConfiguration *conf)
-{
-    DLT_LOG(dltsystem, DLT_LOG_DEBUG, DLT_STRING("dlt-system-filetransfer, start."));
-    static pthread_attr_t t_attr;
-    static pthread_t pt;
-    pthread_create(&pt, &t_attr, (void *)filetransfer_thread, conf);
-    threads.threads[threads.count++] = pt;
-}
diff --git a/src/system/dlt-system-journal.c b/src/system/dlt-system-journal.c
index 2845406..ee3ddf0 100644
--- a/src/system/dlt-system-journal.c
+++ b/src/system/dlt-system-journal.c
@@ -154,7 +154,8 @@ void dlt_system_journal_get_timestamp(sd_journal *journal, MessageTimestamp *tim
         if (errno != 0)
             time_usecs = 0;
     }
-    else if ((ret = sd_journal_get_realtime_usec(journal, &time_usecs)) < 0) {
+    else if ((ret = sd_journal_get_realtime_usec(journal, &time_usecs)) < 0)
+    {
         DLT_LOG(dltsystem, DLT_LOG_WARN,
                 DLT_STRING("dlt-system-journal failed to get realtime: "),
                 DLT_STRING(strerror(-ret)));
@@ -180,7 +181,8 @@ void dlt_system_journal_get_timestamp(sd_journal *journal, MessageTimestamp *tim
         if (errno != 0)
             time_usecs = 0;
     }
-    else if ((ret = sd_journal_get_monotonic_usec(journal, &time_usecs, NULL)) < 0) {
+    else if ((ret = sd_journal_get_monotonic_usec(journal, &time_usecs, NULL)) < 0)
+    {
         DLT_LOG(dltsystem, DLT_LOG_WARN,
                 DLT_STRING("dlt-system-journal failed to get monotonic time: "),
                 DLT_STRING(strerror(-ret)));
@@ -396,14 +398,4 @@ void journal_thread(void *v_conf)
 
 }
 
-void start_systemd_journal(DltSystemConfiguration *conf)
-{
-    DLT_LOG(dltsystem, DLT_LOG_DEBUG,
-            DLT_STRING("dlt-system-journal, start journal"));
-    static pthread_attr_t t_attr;
-    static pthread_t pt;
-    pthread_create(&pt, &t_attr, (void *)journal_thread, conf);
-    threads.threads[threads.count++] = pt;
-}
-
 #endif /* DLT_SYSTEMD_JOURNAL_ENABLE */
diff --git a/src/system/dlt-system-logfile.c b/src/system/dlt-system-logfile.c
index b7ed38a..6466172 100644
--- a/src/system/dlt-system-logfile.c
+++ b/src/system/dlt-system-logfile.c
@@ -143,13 +143,3 @@ void logfile_thread(void *v_conf)
     }
 }
 
-void start_logfile(DltSystemConfiguration *conf)
-{
-    DLT_LOG(dltsystem, DLT_LOG_DEBUG,
-            DLT_STRING("dlt-system-logfile, starting."));
-    DLT_LOG(dltsystem, DLT_LOG_DEBUG, DLT_STRING("Starting thread for logfile"));
-    static pthread_attr_t t_attr;
-    static pthread_t pt;
-    pthread_create(&pt, &t_attr, (void *)logfile_thread, conf);
-    threads.threads[threads.count++] = pt;
-}
diff --git a/src/system/dlt-system-process-handling.c b/src/system/dlt-system-process-handling.c
index 8b89c03..af6ba66 100644
--- a/src/system/dlt-system-process-handling.c
+++ b/src/system/dlt-system-process-handling.c
@@ -119,33 +119,63 @@ void start_threads(DltSystemConfiguration *config)
         threads.threads[i] = 0;
 
 #if defined(DLT_SYSTEMD_WATCHDOG_ENABLE)
-    start_systemd_watchdog(config);
+    start_thread(config, watchdog_thread, "systemd watchdog");
 #endif
 
     if (config->Shell.Enable)
         init_shell();
 
     if (config->LogFile.Enable)
-        start_logfile(config);
+        start_thread(config, logfile_thread, "log file");
 
     if (config->Filetransfer.Enable)
-        start_filetransfer(config);
+        start_thread(config, filetransfer_thread, "file transfer");
 
     if (config->LogProcesses.Enable)
-        start_logprocess(config);
+        start_thread(config, logprocess_thread, "log process");
 
     if (config->Syslog.Enable)
-        start_syslog(config);
+        start_thread(config, syslog_thread, "syslog");
 
 #if defined(DLT_SYSTEMD_JOURNAL_ENABLE)
 
     if (config->Journal.Enable)
-        start_systemd_journal(config);
+        start_thread(config, journal_thread, "systemd journal");
 
 #endif
 }
 
 /**
+ * Start a thread and add it to the thread pool.
+ */
+
+void start_thread(DltSystemConfiguration *conf,
+                  void (thread)(void *), const char *name)
+{
+    if (threads.count == MAX_THREADS) {
+        DLT_LOG(dltsystem, DLT_LOG_ERROR,
+                DLT_STRING("Could not create thread for "),
+                DLT_STRING(name),
+                DLT_STRING("Out of thread slots.\n"));
+        return;
+    }
+
+    DLT_LOG(dltsystem, DLT_LOG_DEBUG, DLT_STRING("Creating thread for "),
+            DLT_STRING(name),
+            DLT_STRING("\n"));
+
+    pthread_t pt;
+
+    if (pthread_create(&pt, NULL, (void *)thread, conf) == 0)
+        threads.threads[threads.count++] = pt;
+    else
+        DLT_LOG(dltsystem, DLT_LOG_ERROR,
+                DLT_STRING("Could not create thread for "),
+                DLT_STRING(name),
+                DLT_STRING("\n"));
+}
+
+/**
  * Wait for threads to exit.
  * There's not actually a condition currently
  * to bail out of file transfer without a signal.
diff --git a/src/system/dlt-system-processes.c b/src/system/dlt-system-processes.c
index 24a6dcf..71f5a1d 100644
--- a/src/system/dlt-system-processes.c
+++ b/src/system/dlt-system-processes.c
@@ -159,13 +159,3 @@ void logprocess_thread(void *v_conf)
         }
     }
 }
-
-void start_logprocess(DltSystemConfiguration *conf)
-{
-    DLT_LOG(dltsystem, DLT_LOG_DEBUG,
-            DLT_STRING("dlt-system-processes, starting process log."));
-    static pthread_attr_t t_attr;
-    static pthread_t pt;
-    pthread_create(&pt, &t_attr, (void *)logprocess_thread, conf);
-    threads.threads[threads.count++] = pt;
-}
diff --git a/src/system/dlt-system-syslog.c b/src/system/dlt-system-syslog.c
index fc59774..0e2e2c4 100644
--- a/src/system/dlt-system-syslog.c
+++ b/src/system/dlt-system-syslog.c
@@ -151,13 +151,3 @@ void syslog_thread(void *v_conf)
 
     close (sock);
 }
-
-void start_syslog(DltSystemConfiguration *conf)
-{
-    DLT_LOG(dltsystem, DLT_LOG_DEBUG,
-            DLT_STRING("dlt-system-syslog, start syslog"));
-    static pthread_attr_t t_attr;
-    static pthread_t pt;
-    pthread_create(&pt, &t_attr, (void *)syslog_thread, conf);
-    threads.threads[threads.count++] = pt;
-}
diff --git a/src/system/dlt-system-watchdog.c b/src/system/dlt-system-watchdog.c
index f85398b..fd6bcac 100644
--- a/src/system/dlt-system-watchdog.c
+++ b/src/system/dlt-system-watchdog.c
@@ -160,17 +160,4 @@ void watchdog_thread(void *v_conf)
         DLT_LOG(watchdogContext, DLT_LOG_ERROR, DLT_STRING("systemd watchdog timeout (WATCHDOG_USEC) is null\n"));
     }
 }
-
-void start_systemd_watchdog(DltSystemConfiguration *conf)
-{
-    DLT_LOG(dltsystem, DLT_LOG_DEBUG, DLT_STRING("Creating thread for systemd watchdog\n"));
-
-    static pthread_attr_t t_attr;
-    static pthread_t pt;
-
-    if (pthread_create(&pt, &t_attr, (void *)watchdog_thread, conf) == 0)
-        threads.threads[threads.count++] = pt;
-    else
-        DLT_LOG(dltsystem, DLT_LOG_ERROR, DLT_STRING("Could not create thread for systemd watchdog\n"));
-}
 #endif
diff --git a/src/system/dlt-system.h b/src/system/dlt-system.h
index 46738b8..e60cb9b 100644
--- a/src/system/dlt-system.h
+++ b/src/system/dlt-system.h
@@ -175,23 +175,25 @@ int read_configuration_file(DltSystemConfiguration *config, char *file_name);
 /* In dlt-process-handling.c */
 int daemonize();
 void start_threads(DltSystemConfiguration *config);
+void start_thread(DltSystemConfiguration *conf,
+                  void (thread)(void *), const char *nam);
 void join_threads();
 void dlt_system_signal_handler(int sig);
 void register_with_dlt(DltSystemConfiguration *config);
 
-/* Thread initiators: */
+/* Threads */
 void init_shell();
-void start_syslog();
-void start_filetransfer(DltSystemConfiguration *conf);
-void start_logfile(DltSystemConfiguration *conf);
-void start_logprocess(DltSystemConfiguration *conf);
+void syslog_thread(void *v_conf);
+void filetransfer_thread(void *v_conf);
+void logfile_thread(void *v_conf);
+void logprocess_thread(void *v_conf);
 
 #if defined(DLT_SYSTEMD_WATCHDOG_ENABLE)
-void start_systemd_watchdog(DltSystemConfiguration *conf);
+void watchdog_thread(void *v_conf);
 #endif
 
 #if defined(DLT_SYSTEMD_JOURNAL_ENABLE)
-void start_systemd_journal(DltSystemConfiguration *conf);
+void journal_thread(void *v_conf);
 #endif
 
 #endif /* DLT_SYSTEM_H_ */