detect: break apart sigtable setup and initialization

Allows initialization to be done early, so the table is ready for
dynamic registration by plugins which are loaded before signature
setup.

src/detect-engine-register.c

@@ -439,7 +439,7 @@ void SigTableCleanup(void)
     }
 }
 
-void SigTableSetup(void)
+void SigTableInit(void)
 {
     if (sigmatch_table == NULL) {
         DETECT_TBLSIZE = DETECT_TBLSIZE_STATIC + DETECT_TBLSIZE_STEP;
@@ -447,10 +447,12 @@ void SigTableSetup(void)
         if (sigmatch_table == NULL) {
             DETECT_TBLSIZE = 0;
             FatalError("Could not allocate sigmatch_table");
-            return;
         }
     }
+}
 
+void SigTableSetup(void)
+{
     DetectSidRegister();
     DetectPriorityRegister();
     DetectPrefilterRegister();

src/detect-engine-register.h

@@ -338,6 +338,7 @@ extern int DETECT_TBLSIZE_IDX;
 #define DETECT_TBLSIZE_STEP 256
 int SigTableList(const char *keyword);
 void SigTableCleanup(void);
+void SigTableInit(void);
 void SigTableSetup(void);
 void SigTableRegisterTests(void);
 

src/runmode-unittests.c

@@ -240,6 +240,7 @@ void RunUnittests(int list_unittests, const char *regex_arg)
     AppLayerSetup();
 
     /* hardcoded initialization code */
+    SigTableInit();
     SigTableSetup(); /* load the rule keywords */
     TmqhSetup();
 

src/suricata.c

@@ -2670,6 +2670,8 @@ int PostConfLoadedSetup(SCInstance *suri)
 
     MacSetRegisterFlowStorage();
 
+    SigTableInit();
+
 #ifdef HAVE_PLUGINS
     SCPluginsLoad(suri->capture_plugin_name, suri->capture_plugin_args);
 #endif

src/tests/fuzz/fuzz_siginit.c

@@ -27,6 +27,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
         MpmTableSetup();
         SpmTableSetup();
         EngineModeSetIDS();
+        SigTableInit();
         SigTableSetup();
     }
     if (cnt++ == 1024) {