fix(printf): zero precision and zero value hash problem

Fixes #26

2 files changed, 27 insertions, 3 deletions

diff --git a/printf.c b/printf.c
index d71665f..9ef669f 100644
--- a/printf.c
+++ b/printf.c
@@ -163,9 +163,9 @@ static size_t _ntoa_format(out_fct_type out, char* buffer, size_t idx, size_t ma
 

   // handle hash

   if (flags & FLAGS_HASH) {

-    if (((len == prec) || (len == width)) && (len > 0U)) {

+    if (len && ((len == prec) || (len == width))) {

       len--;

-      if ((base == 16U) && (len > 0U)) {

+      if (len && (base == 16U)) {

         len--;

       }

     }

@@ -181,7 +181,7 @@ static size_t _ntoa_format(out_fct_type out, char* buffer, size_t idx, size_t ma
   }

 

   // handle sign

-  if ((len == width) && (negative || (flags & FLAGS_PLUS) || (flags & FLAGS_SPACE))) {

+  if (len && (len == width) && (negative || (flags & FLAGS_PLUS) || (flags & FLAGS_SPACE))) {

     len--;

   }

   if (len < PRINTF_NTOA_BUFFER_SIZE) {

@@ -225,6 +225,11 @@ static size_t _ntoa_long(out_fct_type out, char* buffer, size_t idx, size_t maxl
   char buf[PRINTF_NTOA_BUFFER_SIZE];

   size_t len = 0U;

 

+  // no hash for 0 values

+  if (!value) {

+    flags &= ~FLAGS_HASH;

+  }

+

   // write if precision != 0 and value is != 0

   if (!(flags & FLAGS_PRECISION) || value) {

     do {

@@ -245,6 +250,11 @@ static size_t _ntoa_long_long(out_fct_type out, char* buffer, size_t idx, size_t
   char buf[PRINTF_NTOA_BUFFER_SIZE];

   size_t len = 0U;

 

+  // no hash for 0 values

+  if (!value) {

+    flags &= ~FLAGS_HASH;

+  }

+

   // write if precision != 0 and value is != 0

   if (!(flags & FLAGS_PRECISION) || value) {

     do {

diff --git a/test/test_suite.cpp b/test/test_suite.cpp
index e693851..99e07b7 100644
--- a/test/test_suite.cpp
+++ b/test/test_suite.cpp
@@ -247,6 +247,9 @@ TEST_CASE("+ flag", "[]" ) {
 

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

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

+

+  test::sprintf(buffer, "%+.0d", 0);

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

 }

 

 

@@ -344,6 +347,14 @@ TEST_CASE("- flag", "[]" ) {
 }

 

 

+TEST_CASE("# flag", "[]" ) {

+  char buffer[100];

+

+  test::sprintf(buffer, "%#.0x", 0);

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

+}

+

+

 TEST_CASE("specifier", "[]" ) {

   char buffer[100];

 

@@ -1232,6 +1243,9 @@ TEST_CASE("misc", "[]" ) {
   test::sprintf(buffer, "%.3s", "foobar");

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

 

+  test::sprintf(buffer, "% .0d", 0);

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

+

   test::sprintf(buffer, "%10.5d", 4);

   REQUIRE(!strcmp(buffer, "     00004"));