lib: include \n in zlog_msg_text()

Since the file targets append one anyway, save them some extra work.
syslog can use `%.*s` since it's "forced" printf by API anyway.

Signed-off-by: David Lamparter <equinox@diac24.net>

lib/log_filter.c

@@ -111,13 +111,14 @@ int zlog_filter_dump(char *buf, size_t max_size)
 	return len;
 }
 
-static int search_buf(const char *buf)
+static int search_buf(const char *buf, size_t len)
 {
 	char *found = NULL;
 
 	frr_with_mutex(&logfilterlock) {
 		for (int i = 0; i < zlog_filter_count; i++) {
-			found = strstr(buf, zlog_filters[i]);
+			found = memmem(buf, len, zlog_filters[i],
+				       strlen(zlog_filters[i]));
 			if (found != NULL)
 				return 0;
 		}
@@ -131,10 +132,13 @@ static void zlog_filterfile_fd(struct zlog_target *zt, struct zlog_msg *msgs[],
 {
 	struct zlog_msg *msgfilt[nmsgs];
 	size_t i, o = 0;
+	const char *text;
+	size_t text_len;
 
 	for (i = 0; i < nmsgs; i++) {
 		if (zlog_msg_prio(msgs[i]) >= LOG_DEBUG
-		    && search_buf(zlog_msg_text(msgs[i], NULL)) < 0)
+		    && (text = zlog_msg_text(msgs[i], &text_len))
+		    && search_buf(text, text_len) < 0)
 			continue;
 
 		msgfilt[o++] = msgs[i];

lib/zlog.c

@@ -585,7 +585,7 @@ const char *zlog_msg_text(struct zlog_msg *msg, size_t *textlen)
 		va_end(args);
 
 		msg->textlen = need;
-		need += bputch(&fb, '\0');
+		need += bputch(&fb, '\n');
 
 		if (need <= msg->stackbufsz)
 			msg->text = msg->stackbuf;
@@ -603,7 +603,7 @@ const char *zlog_msg_text(struct zlog_msg *msg, size_t *textlen)
 			vbprintfrr(&fb, msg->fmt, args);
 			va_end(args);
 
-			bputch(&fb, '\0');
+			bputch(&fb, '\n');
 		}
 
 		msg->n_argpos = fb.outpos_i;

lib/zlog.h

@@ -142,7 +142,13 @@ struct zlog_msg;
 extern int zlog_msg_prio(struct zlog_msg *msg);
 extern const struct xref_logmsg *zlog_msg_xref(struct zlog_msg *msg);
 
-/* pass NULL as textlen if you don't need it. */
+/* text is NOT \0 terminated; instead there is a \n after textlen since the
+ * logging targets would jump extra hoops otherwise for a single byte.  (the
+ * \n is not included in textlen)
+ *
+ * calling this with NULL textlen is likely wrong.
+ * use  "%.*s", (int)textlen, text  when passing to printf-like functions
+ */
 extern const char *zlog_msg_text(struct zlog_msg *msg, size_t *textlen);
 
 extern void zlog_msg_args(struct zlog_msg *msg, size_t *hdrlen,

lib/zlog_targets.c

@@ -79,15 +79,13 @@ void zlog_fd(struct zlog_target *zt, struct zlog_msg *msgs[], size_t nmsgs)
 		int prio = zlog_msg_prio(msg);
 
 		if (prio <= zt->prio_min) {
-			iov[iovpos].iov_base = ts_pos;
-			if (iovpos > 0)
-				*ts_pos++ = '\n';
-
 			struct fbuf fbuf = {
 				.buf = ts_buf,
 				.pos = ts_pos,
 				.len = sizeof(ts_buf),
 			};
+
+			iov[iovpos].iov_base = ts_pos;
 			zlog_msg_ts(msg, &fbuf,
 				    ZLOG_TS_LEGACY | zte->ts_subsec);
 			ts_pos = fbuf.pos;
@@ -113,7 +111,7 @@ void zlog_fd(struct zlog_target *zt, struct zlog_msg *msgs[], size_t nmsgs)
 
 			iov[iovpos].iov_base =
 				(char *)zlog_msg_text(msg, &textlen);
-			iov[iovpos].iov_len = textlen;
+			iov[iovpos].iov_len = textlen + 1;
 
 			iovpos++;
 		}
@@ -126,11 +124,6 @@ void zlog_fd(struct zlog_target *zt, struct zlog_msg *msgs[], size_t nmsgs)
 		if (iovpos > 0 && (ts_buf + sizeof(ts_buf) - ts_pos < TS_LEN
 				   || i + 1 == nmsgs
 				   || array_size(iov) - iovpos < 5)) {
-			iov[iovpos].iov_base = (char *)"\n";
-			iov[iovpos].iov_len = 1;
-
-			iovpos++;
-
 			writev(fd, iov, iovpos);
 
 			iovpos = 0;
@@ -445,13 +438,16 @@ static void zlog_syslog(struct zlog_target *zt, struct zlog_msg *msgs[],
 {
 	size_t i;
 	struct zlt_syslog *zte = container_of(zt, struct zlt_syslog, zt);
+	const char *text;
+	size_t text_len;
 
 	for (i = 0; i < nmsgs; i++) {
 		if (zlog_msg_prio(msgs[i]) > zt->prio_min)
 			continue;
 
-		syslog(zlog_msg_prio(msgs[i]) | zte->syslog_facility, "%s",
-		       zlog_msg_text(msgs[i], NULL));
+		text = zlog_msg_text(msgs[i], &text_len);
+		syslog(zlog_msg_prio(msgs[i]) | zte->syslog_facility, "%.*s",
+		       (int)text_len, text);
 	}
 }