From ec466f65463e6bfbdf508b50cc2a60593a41b80c Mon Sep 17 00:00:00 2001
From: Quentin Young <qlyoung@cumulusnetworks.com>
Date: Thu, 13 Jun 2019 17:08:05 +0000
Subject: [PATCH] lib: remove snprintf from prefix2str

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>
---
 lib/prefix.c    | 26 +++++++++++++++++++++-----
 tests/subdir.am |  6 ++++++
 2 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/lib/prefix.c b/lib/prefix.c
index 134d9cf908..7abeebcd09 100644
--- a/lib/prefix.c
+++ b/lib/prefix.c
@@ -1329,13 +1329,29 @@ const char *prefix2str(union prefixconstptr pu, char *str, int size)
 {
 	const struct prefix *p = pu.p;
 	char buf[PREFIX2STR_BUFFER];
+	int byte, tmp, a, b;
+	bool z = false;
+	size_t l;
 
 	switch (p->family) {
 	case AF_INET:
 	case AF_INET6:
-		snprintf(str, size, "%s/%d", inet_ntop(p->family, &p->u.prefix,
-						       buf, PREFIX2STR_BUFFER),
-			 p->prefixlen);
+		inet_ntop(p->family, &p->u.prefix, buf, sizeof(buf));
+		l = strlen(buf);
+		buf[l++] = '/';
+		byte = p->prefixlen;
+		if ((tmp = p->prefixlen - 100) >= 0) {
+			buf[l++] = '1';
+			z = true;
+			byte = tmp;
+		}
+		b = byte % 10;
+		a = byte / 10;
+		if (a || z)
+			buf[l++] = '0' + a;
+		buf[l++] = '0' + b;
+		buf[l] = '\0';
+		strlcpy(str, buf, size);
 		break;
 
 	case AF_ETHERNET:
@@ -1349,11 +1365,11 @@ const char *prefix2str(union prefixconstptr pu, char *str, int size)
 		break;
 
 	case AF_FLOWSPEC:
-		sprintf(str, "FS prefix");
+		strlcpy(str, "FS prefix", size);
 		break;
 
 	default:
-		sprintf(str, "UNK prefix");
+		strlcpy(str, "UNK prefix", size);
 		break;
 	}
 
diff --git a/tests/subdir.am b/tests/subdir.am
index 41f1a4873b..270c0811b4 100644
--- a/tests/subdir.am
+++ b/tests/subdir.am
@@ -55,6 +55,7 @@ check_PROGRAMS = \
 	tests/lib/test_memory \
 	tests/lib/test_nexthop_iter \
 	tests/lib/test_ntop \
+	tests/lib/test_prefix2str \
 	tests/lib/test_printfrr \
 	tests/lib/test_privs \
 	tests/lib/test_ringbuf \
@@ -236,6 +237,10 @@ tests_lib_test_ntop_CFLAGS = $(TESTS_CFLAGS)
 tests_lib_test_ntop_CPPFLAGS = $(TESTS_CPPFLAGS)
 tests_lib_test_ntop_LDADD = # none
 tests_lib_test_ntop_SOURCES = tests/lib/test_ntop.c tests/helpers/c/prng.c
+tests_lib_test_prefix2str_CFLAGS = $(TESTS_CFLAGS)
+tests_lib_test_prefix2str_CPPFLAGS = $(TESTS_CPPFLAGS)
+tests_lib_test_prefix2str_LDADD = $(ALL_TESTS_LDADD)
+tests_lib_test_prefix2str_SOURCES = tests/lib/test_prefix2str.c tests/helpers/c/prng.c
 tests_lib_test_printfrr_CFLAGS = $(TESTS_CFLAGS)
 tests_lib_test_printfrr_CPPFLAGS = $(TESTS_CPPFLAGS)
 tests_lib_test_printfrr_LDADD = $(ALL_TESTS_LDADD)
@@ -328,6 +333,7 @@ EXTRA_DIST += \
 	tests/lib/test_atomlist.py \
 	tests/lib/test_nexthop_iter.py \
 	tests/lib/test_ntop.py \
+	tests/lib/test_prefix2str.py \
 	tests/lib/test_printfrr.py \
 	tests/lib/test_ringbuf.py \
 	tests/lib/test_srcdest_table.py \