fix(printf): fix trailing field width in itoa conversion

Fixes #21

2 files changed, 15 insertions, 1 deletions

diff --git a/printf.c b/printf.c
index c28cf13..e4c83e5 100644
--- a/printf.c
+++ b/printf.c
@@ -151,6 +151,8 @@ static inline unsigned int _atoi(const char** str)
 // internal itoa format

 static size_t _ntoa_format(out_fct_type out, char* buffer, size_t idx, size_t maxlen, char* buf, size_t len, bool negative, unsigned int base, unsigned int prec, unsigned int width, unsigned int flags)

 {

+  const size_t start_idx = idx;

+

   // pad leading zeros

   while (!(flags & FLAGS_LEFT) && (len < prec) && (len < PRINTF_NTOA_BUFFER_SIZE)) {

     buf[len++] = '0';

@@ -208,7 +210,7 @@ static size_t _ntoa_format(out_fct_type out, char* buffer, size_t idx, size_t ma
 

   // append pad spaces up to given width

   if (flags & FLAGS_LEFT) {

-    while (idx < width) {

+    while (idx - start_idx < width) {

       out(' ', buffer, idx++, maxlen);

     }

   }

diff --git a/test/test_suite.cpp b/test/test_suite.cpp
index 212fbd3..3ecac5f 100644
--- a/test/test_suite.cpp
+++ b/test/test_suite.cpp
@@ -582,6 +582,18 @@ TEST_CASE("width -20", "[]" ) {
 

   test::sprintf(buffer, "%-20c", 'x');

   REQUIRE(!strcmp(buffer, "x                   "));

+

+  test::sprintf(buffer, "|%5d| |%-2d| |%5d|", 9, 9, 9);

+  REQUIRE(!strcmp(buffer, "|    9| |9 | |    9|"));

+

+  test::sprintf(buffer, "|%5d| |%-2d| |%5d|", 10, 10, 10);

+  REQUIRE(!strcmp(buffer, "|   10| |10| |   10|"));

+

+  test::sprintf(buffer, "|%5d| |%-12d| |%5d|", 9, 9, 9);

+  REQUIRE(!strcmp(buffer, "|    9| |9           | |    9|"));

+

+  test::sprintf(buffer, "|%5d| |%-12d| |%5d|", 10, 10, 10);

+  REQUIRE(!strcmp(buffer, "|   10| |10          | |   10|"));

 }