Fix strncat/wcsncat

Previously, no checks were done when __n <= __b, but strncat _appends_ after
existing content, making this a overly broad check check. For example, with an
8-byte buffer containing "12345\0", strncat(buf, "ABCD", 4) would have the
check skipped, but the result "12345ABCD\0" is 10 bytes, resulting in an
overflow.

This commit fixes this oversight, and adds a bunch of tests.

1 files changed, 10 insertions, 0 deletions

diff --git a/tests/Makefile b/tests/Makefile
index 6904b2d..9bedd16 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -84,6 +84,11 @@ RUNTIME_TARGETS= \
         test_strlcpy_dynamic_write    \
         test_strlcpy_static_write     \
         test_strncat_dynamic_write    \
+        test_strncat_n_eq_buf          \
+        test_strncat_n_gt_buf          \
+        test_strncat_n_lt_buf          \
+        test_strncat_n_one             \
+        test_strncat_safe              \
         test_strncat_static_write     \
         test_strncpy_dynamic_write    \
         test_strncpy_static_write     \
@@ -101,6 +106,11 @@ RUNTIME_TARGETS= \
         test_wcsnrtombs_static        \
         test_wcscat_static_write      \
         test_wcscpy_static_write      \
+        test_wcsncat_n_eq_buf          \
+        test_wcsncat_n_gt_buf          \
+        test_wcsncat_n_lt_buf          \
+        test_wcsncat_n_one             \
+        test_wcsncat_safe              \
         test_wcsncat_static_write     \
         test_wcsncpy_static_write     \
         test_wmemcpy_dynamic_read     \