initial work on omprog, an output module to send messages to another program

3 files changed, 93 insertions, 19 deletions

diff --git a/plugins/omdtn/Makefile.am b/plugins/omdtn/Makefile.am
deleted file mode 100644
index afb57476..00000000
--- a/plugins/omdtn/Makefile.am
+++ /dev/null
@@ -1,8 +0,0 @@
-pkglib_LTLIBRARIES = omdtn.la
-
-omdtn_la_SOURCES = omdtn.c
-omdtn_la_CPPFLAGS =  $(RSRT_CFLAGS) $(PTHREADS_CFLAGS)
-omdtn_la_LDFLAGS = -module -avoid-version
-omdtn_la_LIBADD = 
-
-EXTRA_DIST = 
diff --git a/plugins/omprog/Makefile.am b/plugins/omprog/Makefile.am
new file mode 100644
index 00000000..63fe09b8
--- /dev/null
+++ b/plugins/omprog/Makefile.am
@@ -0,0 +1,8 @@
+pkglib_LTLIBRARIES = omprog.la
+
+omprog_la_SOURCES = omprog.c
+omprog_la_CPPFLAGS =  $(RSRT_CFLAGS) $(PTHREADS_CFLAGS)
+omprog_la_LDFLAGS = -module -avoid-version
+omprog_la_LIBADD = 
+
+EXTRA_DIST = 
diff --git a/plugins/omdtn/omdtn.c b/plugins/omprog/omprog.c
index 761bde79..0cdacf78 100644
--- a/plugins/omdtn/omdtn.c
+++ b/plugins/omprog/omprog.c
@@ -1,11 +1,6 @@
-/* omdtn.c
- * This is the plugin for rsyslog use in the interplanetary Internet,
- * especially useful for rsyslog in space ships of all kinds.
- * The core idea was introduced in early 2009 and considered
- * doable.
- *
- * Note that this has not yet been tested for robustness but needs
- * to prior to placing it on top of a rocket.
+/* omprog.c
+ * This output plugin enables rsyslog to execute a program and
+ * feed it the message stream as standard input.
  *
  * NOTE: read comments in module-template.h for more specifics!
  *
@@ -55,8 +50,15 @@ MODULE_TYPE_OUTPUT
 DEF_OMOD_STATIC_DATA
 
 typedef struct _instanceData {
+	uchar *szBinary;	/* name of binary to call */
+	pid_t pid;		/* pid of currently running process */
+	int fdPipe;		/* file descriptor to write to */
+	int bIsRunning;		/* is binary currently running? 0-no, 1-yes */
 } instanceData;
 
+/* config settings */
+static uchar *szBinary = NULL;	/* name of binary to call */
+
 BEGINcreateInstance
 CODESTARTcreateInstance
 ENDcreateInstance
@@ -83,9 +85,57 @@ BEGINtryResume
 CODESTARTtryResume
 ENDtryResume
 
+/* creates a pipe and starts program, uses pipe as stdin for program.
+ * rgerhards, 2009-04-01
+ */
+static rsRetVal
+openPipe(instanceData *pData)
+{
+	int pipefd[2];
+	pid_t cpid;
+	char *newargv[] = { NULL };
+	char *newenviron[] = { NULL };
+	DEFiRet;
+
+	assert(pData != NULL);
+
+	if(pipe(pipefd) == -1) {
+		ABORT_FINALIZE(RS_RET_ERR_CREAT_PIPE);
+	}
+
+	cpid = fork();
+	if(cpid == -1) {
+		ABORT_FINALIZE(RS_RET_ERR_FORK);
+	}
+
+	if(cpid == 0) {    
+		/* we are now the child, just set the right selectors and
+		 * exec the binary. If that fails, there is not much we can do.
+		 */
+		fclose(stdin);
+		dup(pipefd[0]);
+		close(pipefd[1]);
+		//fclose(stdout);
+fprintf(stderr, "Program to exec '%s', fdPipe: %d\n", pData->szBinary, pipefd[0]);
+		execve((char*)pData->szBinary, newargv, newenviron);
+	}
+
+	pData->fdPipe = pipefd[1];
+	pData->pid = cpid;
+	close(pipefd[0]);
+	pData->bIsRunning = 1;
+finalize_it:
+	RETiRet;
+}
+
+
 BEGINdoAction
 CODESTARTdoAction
-	write(1, (char*)ppString[0], strlen((char*)ppString[0]));
+	if(pData->bIsRunning == 0) {
+		openPipe(pData);
+	}
+
+	write(pData->fdPipe, (char*)ppString[0], strlen((char*)ppString[0]));
 ENDdoAction
 
 
@@ -93,14 +143,15 @@ BEGINparseSelectorAct
 CODESTARTparseSelectorAct
 CODE_STD_STRING_REQUESTparseSelectorAct(1)
 	/* first check if this config line is actually for us */
-	if(strncmp((char*) p, ":omstdout:", sizeof(":omstdout:") - 1)) {
+	if(strncmp((char*) p, ":omprog:", sizeof(":omprog:") - 1)) {
 		ABORT_FINALIZE(RS_RET_CONFLINE_UNPROCESSED);
 	}
 
 	/* ok, if we reach this point, we have something for us */
-	p += sizeof(":omstdout:") - 1; /* eat indicator sequence  (-1 because of '\0'!) */
+	p += sizeof(":omprog:") - 1; /* eat indicator sequence  (-1 because of '\0'!) */
 	CHKiRet(createInstance(&pData));
 
+	CHKmalloc(pData->szBinary = (uchar*) strdup((char*)szBinary));
 	/* check if a non-standard template is to be applied */
 	if(*(p-1) == ';')
 		--p;
@@ -111,6 +162,10 @@ ENDparseSelectorAct
 
 BEGINmodExit
 CODESTARTmodExit
+	if(szBinary != NULL) {
+		free(szBinary);
+		szBinary = NULL;
+	}
 ENDmodExit
 
 
@@ -120,10 +175,29 @@ CODEqueryEtryPt_STD_OMOD_QUERIES
 ENDqueryEtryPt
 
 
+
+/* Reset config variables for this module to default values.
+ */
+static rsRetVal resetConfigVariables(uchar __attribute__((unused)) *pp, void __attribute__((unused)) *pVal)
+{
+	DEFiRet;
+
+	if(szBinary != NULL) {
+		free(szBinary);
+		szBinary = NULL;
+	}
+
+	RETiRet;
+}
+
+
 BEGINmodInit()
 CODESTARTmodInit
 	*ipIFVersProvided = CURR_MOD_IF_VERSION; /* we only support the current interface specification */
 CODEmodInit_QueryRegCFSLineHdlr
+	CHKiRet(omsdRegCFSLineHdlr((uchar *)"actionomprogbinary", 0, eCmdHdlrGetWord, NULL, &szBinary, STD_LOADABLE_MODULE_ID));
+	CHKiRet(omsdRegCFSLineHdlr((uchar *)"resetconfigvariables", 1, eCmdHdlrCustomHandler, resetConfigVariables, NULL, STD_LOADABLE_MODULE_ID));
+CODEmodInit_QueryRegCFSLineHdlr
 ENDmodInit
 
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