1 files changed, 45 insertions, 0 deletions
diff --git a/src/modules/systemlib/mixer/mixer.cpp b/src/modules/systemlib/mixer/mixer.cpp
index df0dfe838..cce46bf5f 100644
--- a/src/modules/systemlib/mixer/mixer.cpp
+++ b/src/modules/systemlib/mixer/mixer.cpp
@@ -50,6 +50,8 @@
 #include <stdio.h>
 #include <math.h>
 #include <unistd.h>
+#include <ctype.h>
+#include <systemlib/err.h>
 
 #include "mixer.h"
 
@@ -114,6 +116,33 @@ Mixer::scale_check(struct mixer_scaler_s &scaler)
 	return 0;
 }
 
+const char *
+Mixer::findtag(const char *buf, unsigned &buflen, char tag)
+{
+	while (buflen >= 2) {
+		if ((buf[0] == tag) && (buf[1] == ':'))
+			return buf;
+		buf++;
+		buflen--;
+	}
+	return nullptr;
+}
+
+const char *
+Mixer::skipline(const char *buf, unsigned &buflen)
+{
+	const char *p;
+
+	/* if we can find a CR or NL in the buffer, skip up to it */
+	if ((p = (const char *)memchr(buf, '\r', buflen)) || (p = (const char *)memchr(buf, '\n', buflen))) {
+		/* skip up to it AND one beyond - could be on the NUL symbol now */
+		buflen -= (p - buf) + 1;
+		return p + 1;
+	}
+
+	return nullptr;
+}
+
 /****************************************************************************/
 
 NullMixer::NullMixer() :
@@ -142,6 +171,22 @@ NullMixer *
 NullMixer::from_text(const char *buf, unsigned &buflen)
 {
 	NullMixer *nm = nullptr;
+	const char *end = buf + buflen;
+
+	/* enforce that the mixer ends with space or a new line */
+	for (int i = buflen - 1; i >= 0; i--) {
+		if (buf[i] == '\0')
+			continue;
+
+		/* require a space or newline at the end of the buffer, fail on printable chars */
+		if (buf[i] == ' ' || buf[i] == '\n' || buf[i] == '\r') {
+			/* found a line ending or space, so no split symbols / numbers. good. */
+			break;
+		} else {
+			return nm;
+		}
+
+	}
 
 	if ((buflen >= 2) && (buf[0] == 'Z') && (buf[1] == ':')) {
 		nm = new NullMixer;