logread: add option to filter for facilities

This adds filtering options for facilities as follows:
    -z	<facility>	handle only messages with given facility (0-23), repeatable
    -Z	<facility>	ignore messages with given facility (0-23), repeatable

With that
* 'logread -z 2 -z 16' will display all MAIL and LOCAL0 messages, while
* 'logread -Z 2 -Z 16' will display all but MAIL and LOCAL0 messages

Signed-off-by: Zefir Kurtisi <zefir.kurtisi@neratec.com>

diff --git a/log/logread.c b/log/logread.c
index e47541a19f5aaef724f1118a0ad26b7a0619d5ea..a7647421e95d2774332ce5d9de91756b5657faf9 100644 (file)
--- a/log/logread.c
+++ b/log/logread.c
@@ -66,6 +66,18 @@ static int log_type = LOG_STDOUT;
 static int log_size, log_udp, log_follow, log_trailer_null = 0;
 static int log_timestamp;
 static int logd_conn_tries = LOGD_CONNECT_RETRY;
+static int facility_include;
+static int facility_exclude;
+
+/* check for facility filter; return 0 if message shall be dropped */
+static int check_facility_filter(int f)
+{
+       if (facility_include)
+               return !!(facility_include & (1 << f));
+       if (facility_exclude)
+               return !(facility_exclude & (1 << f));
+       return 1;
+}
 
 static const char* getcodetext(int value, CODE *codetable) {
        CODE *i;
@@ -133,6 +145,10 @@ static int log_notify(struct blob_attr *msg)
                        exit(-1);
                }
        }
+       p = blobmsg_get_u32(tb[LOG_PRIO]);
+
+       if (!check_facility_filter(LOG_FAC(p)))
+                       return 0;
 
        m = blobmsg_get_string(tb[LOG_MSG]);
        if (regexp_pattern &&
@@ -145,7 +161,6 @@ static int log_notify(struct blob_attr *msg)
                                (unsigned long)t, t_ms);
        }
        c = ctime(&t);
-       p = blobmsg_get_u32(tb[LOG_PRIO]);
        c[strlen(c) - 1] = '\0';
 
        if (log_type == LOG_NET) {
@@ -212,6 +227,8 @@ static int usage(const char *prog)
                "    -p <file>          PID file\n"
                "    -h <hostname>      Add hostname to the message\n"
                "    -P <prefix>        Prefix custom text to streamed messages\n"
+               "    -z <facility>      handle only messages with given facility (0-23), repeatable\n"
+               "    -Z <facility>      ignore messages with given facility (0-23), repeatable\n"
                "    -f                 Follow log messages\n"
                "    -u                 Use UDP as the protocol\n"
                "    -t                 Add an extra timestamp\n"
@@ -290,7 +307,7 @@ int main(int argc, char **argv)
 
        signal(SIGPIPE, SIG_IGN);
 
-       while ((ch = getopt(argc, argv, "u0fcs:l:r:F:p:S:P:h:e:t")) != -1) {
+       while ((ch = getopt(argc, argv, "u0fcs:l:z:Z:r:F:p:S:P:h:e:t")) != -1) {
                switch (ch) {
                case 'u':
                        log_udp = 1;
@@ -320,6 +337,14 @@ int main(int argc, char **argv)
                case 'l':
                        lines = atoi(optarg);
                        break;
+               case 'z':
+                       id = strtoul(optarg, NULL, 0) & 0x1f;
+                       facility_include |= (1 << id);
+                       break;
+               case 'Z':
+                       id = strtoul(optarg, NULL, 0) & 0x1f;
+                       facility_exclude |= (1 << id);
+                       break;
                case 'S':
                        log_size = atoi(optarg);
                        if (log_size < 1)