diff --git a/src/util/strings.c b/src/util/strings.c
index e469c2a18..df15ab588 100644
--- a/src/util/strings.c
+++ b/src/util/strings.c
@@ -256,6 +256,26 @@ char *str_strdup(const char *s) {
 #endif
 }
 
+void sbs_printf(struct sbstring *sbs, const char *format, ...)
+{
+    size_t size = sbs->size - (sbs->end - sbs->begin);
+
+    if (size > 0) {
+        va_list argp;
+        va_start(argp, format);
+        int bytes = vsnprintf(sbs->end, size, format, argp);
+        if (bytes > 0) {
+            if ((size_t)bytes >= size) {
+                bytes = size - 1;
+                /* terminate truncated output */
+                sbs->end[bytes] = '\0';
+            }
+            sbs->end += bytes;
+        }
+        va_end(argp);
+    }
+}
+
 void sbs_init(struct sbstring *sbs, char *buffer, size_t size)
 {
     assert(sbs);
diff --git a/src/util/strings.h b/src/util/strings.h
index 29ca11ef7..acce3767b 100644
--- a/src/util/strings.h
+++ b/src/util/strings.h
@@ -48,6 +48,7 @@ extern "C" {
         char *end;
     } sbstring;
 
+    void sbs_printf(struct sbstring *sbs, const char *format, ...);
     void sbs_init(struct sbstring *sbs, char *buffer, size_t size);
     void sbs_adopt(struct sbstring *sbs, char *buffer, size_t size);
     void sbs_strcat(struct sbstring *sbs, const char *str);
diff --git a/src/util/strings.test.c b/src/util/strings.test.c
index b9ab8c729..399f6a4dd 100644
--- a/src/util/strings.test.c
+++ b/src/util/strings.test.c
@@ -234,6 +234,31 @@ static void test_sbs_substr(CuTest * tc)
     CuAssertIntEquals(tc, 'A', buffer[9]);
 }
 
+static void test_sbs_printf(CuTest * tc)
+{
+    char buffer[10];
+    sbstring sbs;
+
+    sbs_init(&sbs, buffer, sizeof(buffer));
+    sbs_printf(&sbs, "%s %d", "1234", 5678);
+    CuAssertStrEquals(tc, "1234 5678", buffer);
+
+    sbs_init(&sbs, buffer, sizeof(buffer));
+    sbs_printf(&sbs, "%s", "12345");
+    sbs_printf(&sbs, "%d", 6789);
+    CuAssertStrEquals(tc, "123456789", buffer);
+
+    sbs_init(&sbs, buffer, sizeof(buffer));
+    sbs_printf(&sbs, "%s", "1234567890");
+    CuAssertStrEquals(tc, "123456789", buffer);
+
+    sbs_init(&sbs, buffer, sizeof(buffer));
+    sbs_printf(&sbs, "%d", 123456789);
+    CuAssertStrEquals(tc, "123456789", buffer);
+    sbs_printf(&sbs, "%s", "Hodor");
+    CuAssertStrEquals(tc, "123456789", buffer);
+}
+
 CuSuite *get_strings_suite(void)
 {
     CuSuite *suite = CuSuiteNew();
@@ -249,5 +274,6 @@ CuSuite *get_strings_suite(void)
     SUITE_ADD_TEST(suite, test_sbstring);
     SUITE_ADD_TEST(suite, test_sbs_strcat);
     SUITE_ADD_TEST(suite, test_sbs_substr);
+    SUITE_ADD_TEST(suite, test_sbs_printf);
     return suite;
 }