enhanced configuration file error reporting and verification

- enhanced config file checking - no active actions are detected
- added -N rsyslogd command line option for a config validation run
  (which does not execute actual syslogd code and does not interfere
  with a running instance)
- somewhat improved emergency configuration. It is now also selected
  if the config contains no active actions
- rsyslogd error messages are now reported to stderr by default. can be
  turned off by the new "$ErrorMessagesToStderr off" directive
Thanks to HKS for suggesting these new features.

3 files changed, 38 insertions, 1 deletions

diff --git a/runtime/conf.c b/runtime/conf.c
index 71b2b2da..6a7caa41 100644
--- a/runtime/conf.c
+++ b/runtime/conf.c
@@ -83,6 +83,8 @@ DEFobjCurrIf(module)
 DEFobjCurrIf(errmsg)
 DEFobjCurrIf(net)
 
+static int iNbrActions; /* number of actions the running config has. Needs to be init on ReInitConf() */
+
 /* The following global variables are used for building
  * tag and host selector lines during startup and config reload.
  * This is stored as a global variable pool because of its ease. It is
@@ -1060,6 +1062,7 @@ static rsRetVal cflineDoAction(uchar **p, action_t **ppAction)
 					pAction->f_ReduceRepeated = 0;
 				}
 				pAction->bEnabled = 1; /* action is enabled */
+				iNbrActions++;	/* one more active action! */
 			}
 			break;
 		}
@@ -1159,6 +1162,34 @@ cfline(uchar *line, selector_t **pfCurr)
 }
 
 
+/* Reinitialize the configuration subsystem. This is a "work-around" to the fact
+ * that we do not yet have actual config objects. This method is to be called
+ * whenever a totally new config is started (which means on startup and HUP).
+ * Note that it MUST NOT be called for an included config file.
+ * rgerhards, 2008-07-28
+ */
+static rsRetVal
+ReInitConf(void)
+{
+	DEFiRet;
+	iNbrActions = 0;	/* this is what we created the function for ;) - action count is reset */
+	RETiRet;
+}
+
+
+/* return the current number of active actions
+ * rgerhards, 2008-07-28
+ */
+static rsRetVal
+GetNbrActActions(int *piNbrActions)
+{
+	DEFiRet;
+	assert(piNbrActions != NULL);
+	*piNbrActions = iNbrActions;
+	RETiRet;
+}
+
+
 /* queryInterface function
  * rgerhards, 2008-02-29
  */
@@ -1179,6 +1210,8 @@ CODESTARTobjQueryInterface(conf)
 	pIf->doIncludeLine = doIncludeLine;
 	pIf->cfline = cfline;
 	pIf->processConfFile = processConfFile;
+	pIf->ReInitConf = ReInitConf;
+	pIf->GetNbrActActions = GetNbrActActions;
 
 finalize_it:
 ENDobjQueryInterface(conf)
diff --git a/runtime/conf.h b/runtime/conf.h
index 31ca27b3..2494d4dc 100644
--- a/runtime/conf.h
+++ b/runtime/conf.h
@@ -37,8 +37,10 @@ BEGINinterface(conf) /* name must also be changed in ENDinterface macro! */
 	rsRetVal (*doIncludeLine)(uchar **pp, __attribute__((unused)) void* pVal);
 	rsRetVal (*cfline)(uchar *line, selector_t **pfCurr);
 	rsRetVal (*processConfFile)(uchar *pConfFile);
+	rsRetVal (*ReInitConf)(void);
+	rsRetVal (*GetNbrActActions)(int *);
 ENDinterface(conf)
-#define confCURR_IF_VERSION 1 /* increment whenever you change the interface structure! */
+#define confCURR_IF_VERSION 2 /* increment whenever you change the interface structure! */
 
 
 /* prototypes */
diff --git a/runtime/rsyslog.h b/runtime/rsyslog.h
index 95b2c756..61d81f90 100644
--- a/runtime/rsyslog.h
+++ b/runtime/rsyslog.h
@@ -123,6 +123,7 @@ enum rsRetVal_				/** return value. All methods return this if not specified oth
 	RS_RET_TRUE = -3,		/**< to indicate a true state (can be used as TRUE, legacy) */
 	RS_RET_FALSE = -2,		/**< to indicate a false state (can be used as FALSE, legacy) */
 	RS_RET_NO_IRET = -8,	/**< This is a trick for the debuging system - it means no iRet is provided  */
+	RS_RET_VALIDATION_RUN = -9,	/**< indicates a (config) validation run, processing not carried out */
 	RS_RET_ERR = -3000,	/**< generic failure */
 	RS_TRUNCAT_TOO_LARGE = -3001, /**< truncation operation where too many chars should be truncated */
 	RS_RET_FOUND_AT_STRING_END = -3002, /**< some value found, but at the last pos of string */
@@ -248,6 +249,7 @@ enum rsRetVal_				/** return value. All methods return this if not specified oth
 	RS_RET_RETRY = -2100, /**< call should be retried (e.g. EGAIN on recv) */
 	RS_RET_GSS_ERR = -2101, /**< generic error occured in GSSAPI subsystem */
 	RS_RET_CERTLESS = -2102, /**< state: we run without machine cert (this may be OK) */
+	RS_RET_NO_ACTIONS = -2103, /**< no active actions are configured (no output will be created) */
 
 	/* RainerScript error messages (range 1000.. 1999) */
 	RS_RET_SYSVAR_NOT_FOUND = 1001, /**< system variable could not be found (maybe misspelled) */