fix(printf): fctprintf() must not append null terminator

Fixes #39, references #19

2 files changed, 6 insertions, 3 deletions

diff --git a/printf.c b/printf.c
index df88d3d..c9a1175 100644
--- a/printf.c
+++ b/printf.c
@@ -134,8 +134,10 @@ static inline void _out_char(char character, void* buffer, size_t idx, size_t ma
 static inline void _out_fct(char character, void* buffer, size_t idx, size_t maxlen)

 {

   (void)idx; (void)maxlen;

-  // buffer is the output fct pointer

-  ((out_fct_wrap_type*)buffer)->fct(character, ((out_fct_wrap_type*)buffer)->arg);

+  if (character) {

+    // buffer is the output fct pointer

+    ((out_fct_wrap_type*)buffer)->fct(character, ((out_fct_wrap_type*)buffer)->arg);

+  }

 }

 

 

diff --git a/test/test_suite.cpp b/test/test_suite.cpp
index bcddd4f..100b59f 100644
--- a/test/test_suite.cpp
+++ b/test/test_suite.cpp
@@ -69,7 +69,8 @@ TEST_CASE("fctprintf", "[]" ) {
   printf_idx = 0U;

   memset(printf_buffer, 0xCC, 100U);

   test::fctprintf(&_out_fct, nullptr, "This is a test of %X", 0x12EFU);

-  REQUIRE(!strcmp(printf_buffer, "This is a test of 12EF"));

+  REQUIRE(!strncmp(printf_buffer, "This is a test of 12EF", 22U));

+  REQUIRE(printf_buffer[22] == (char)0xCC);

 }