userspace/snmpd: add wrsBootUserspaceDaemonsMissing to wrsBootStatusGroup

Checking if all processes from array "userspace_deamons" are running.
Can return to snmp:
--all running
--error (cannot run ps or problem with multiple process' instances)
--number of missing processes

Signed-off-by: Adam Wujek <adam.wujek@cern.ch>

userspace/snmpd/WR-SWITCH-MIB.txt

@@ -382,6 +382,20 @@ wrsBootKernelModulesMissing  OBJECT-TYPE
         other errors (like unable to open /proc/modules) are reported as maximum number of missing modules"
     ::= { wrsBootStatusGroup 13 }
 
+wrsBootUserspaceDaemonsMissing  OBJECT-TYPE
+    SYNTAX       INTEGER {
+                        allDeamonsPresent(0)
+    }
+    MAX-ACCESS    read-only
+    STATUS        current
+    DESCRIPTION
+        "Checking if all desired deamons are running.
+        allDeamonsPresent - all deamons running
+        other numbers represent number of deamons not running
+        other errors (can be: unable to run ps command or problem with multiple process instances) 
+        are reported as maximum number of missing modules"
+    ::= { wrsBootStatusGroup 14 }
+
 -- wrsTemperatureGroup (.7.1.3)
 wrsTemperatureGroup     OBJECT IDENTIFIER ::= { wrsOperationStatus 3 }
 

userspace/snmpd/wrsBootStatusGroup.c

@@ -15,6 +15,8 @@
 #define LOAD_LM32_STATUS_FILE "/tmp/load_lm32_status"
 
 #define MODULES_FILE "/proc/modules"
+/* get process list, output only process' command */
+#define PROCESS_COMMAND "/bin/ps axo command"
 
 /* Macros for fscanf function to read line with maximum of "x" characters
  * without new line. Macro expands to something like: "%10[^\n]" */
@@ -39,6 +41,7 @@ static struct pickinfo wrsBootStatus_pickinfo[] = {
 	FIELD(wrsBootStatus_s, ASN_INTEGER, wrsBootLoadFPGA),
 	FIELD(wrsBootStatus_s, ASN_INTEGER, wrsBootLoadLM32),
 	FIELD(wrsBootStatus_s, ASN_INTEGER, wrsBootKernelModulesMissing),
+	FIELD(wrsBootStatus_s, ASN_INTEGER, wrsBootUserspaceDaemonsMissing),
 };
 
 struct wrsBootStatus_s wrsBootStatus_s;
@@ -58,6 +61,23 @@ static struct wrs_km_item kernel_modules[] = {
 	[6] = {"g_serial"},
 };
 
+/* user space deamon list item */
+struct wrs_usd_item {
+	char *key;
+};
+
+/* user space deamon list */
+static struct wrs_km_item userspace_deamons[] = {
+	[0] = {.key = "/usr/sbin/dropbear"},
+	[1] = {"/wr/bin/wrsw_hal"}, /* two wrsw_hal instances */
+	[2] = {"/wr/bin/wrsw_hal"}, /* two wrsw_hal instances */
+	[3] = {"/wr/bin/wrsw_rtud"},
+	[4] = {"/wr/bin/ppsi"},
+	[5] = {"/usr/sbin/lighttpd"},
+	[6] = {"/usr/bin/monit"},
+	[7] = {"snmpd"},
+};
+
 struct wrs_bc_item {
 	char *key;
 	uint32_t value;
@@ -347,6 +367,58 @@ static void get_loaded_kernel_modules_status(void)
 	fclose(f);
 }
 
+/* check if deamons from userspace_deamons array are running */
+static void get_deamons_status(void)
+{
+	FILE *f;
+	char key[41]; /* 1 for null char */
+	int ret;
+	int i;
+	int processes_found;
+	int processes_missing;
+
+	/* use ps command to get process list, more portable, less error prone
+	 * but probably slower than manually parsing /proc/ */
+	f = popen(PROCESS_COMMAND, "r");
+	if (!f) {
+		snmp_log(LOG_ERR, "SNMP: wrsBootStatusGroup failed to execute "
+			 PROCESS_COMMAND"\n");
+		/* notify snmp about error in processes list */
+		wrsBootStatus_s.wrsBootUserspaceDaemonsMissing =
+						ARRAY_SIZE(userspace_deamons);
+		return;
+	}
+
+	while (ret != EOF) {
+		/* read first word from line (process name) ignore rest of
+		 * the line */
+		ret = fscanf(f, "%40s%*[^\n]", key);
+		if (ret != 1)
+			continue; /* error... or EOF */
+
+		for (i = 0; i < ARRAY_SIZE(userspace_deamons); i++) {
+			if (strncmp(key, userspace_deamons[i].key, 40))
+				continue;
+			processes_found++;
+			break;
+		}
+	}
+
+	processes_missing = ARRAY_SIZE(userspace_deamons) - processes_found;
+
+	/* save number of processes missing */
+	if (processes_missing < 0) {
+		/* probably something wrong with multiple process' instances */
+		wrsBootStatus_s.wrsBootUserspaceDaemonsMissing =
+						ARRAY_SIZE(userspace_deamons);
+	} else {
+		wrsBootStatus_s.wrsBootUserspaceDaemonsMissing =
+							processes_missing;
+	}
+
+	pclose(f);
+}
+
 time_t wrsBootStatus_data_fill(void)
 {
 	static time_t time_update;
@@ -371,6 +443,9 @@ time_t wrsBootStatus_data_fill(void)
 	/* get loaded kernel modules */
 	get_loaded_kernel_modules_status();
 
+	/* get info about running deamons */
+	get_deamons_status();
+
 	/* there was an update, return current time */
 	return time_update;
 }

userspace/snmpd/wrsBootStatusGroup.h

@@ -52,6 +52,7 @@ struct wrsBootStatus_s {
 	int32_t wrsBootLoadFPGA;
 	int32_t wrsBootLoadLM32;
 	int32_t wrsBootKernelModulesMissing;
+	int32_t wrsBootUserspaceDaemonsMissing;
 };
 
 extern struct wrsBootStatus_s wrsBootStatus_s;