Factoring output padding code to ensure "nan" gets padded correctly

1 files changed, 28 insertions, 48 deletions

diff --git a/printf.c b/printf.c
index dd92831..7c346bf 100644
--- a/printf.c
+++ b/printf.c
@@ -186,11 +186,34 @@ static unsigned int _atoi(const char** str)
   return i;

 }

 

-// 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)

+// output the specified string in reverse, taking care of any zero-padding

+static size_t _out_rev(out_fct_type out, char* buffer, size_t idx, size_t maxlen, const char* buf, size_t len, unsigned int width, unsigned int flags)

 {

   const size_t start_idx = idx;

+  

+  // pad spaces up to given width

+  if (!(flags & FLAGS_LEFT) && !(flags & FLAGS_ZEROPAD)) {

+    for (size_t i = len; i < width; i++) {

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

+    }

+  }

+

+  // reverse string

+  while (len) out(buf[--len], buffer, idx++, maxlen);

 

+  // append pad spaces up to given width

+  if (flags & FLAGS_LEFT) {

+    while (idx - start_idx < width) {

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

+    }

+  }

+  

+  return idx;

+}

+

+// 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)

+{

   // pad leading zeros

   if (!(flags & FLAGS_LEFT)) {

     if (width && (flags & FLAGS_ZEROPAD) && (negative || (flags & (FLAGS_PLUS | FLAGS_SPACE)))) {

@@ -238,26 +261,7 @@ static size_t _ntoa_format(out_fct_type out, char* buffer, size_t idx, size_t ma
     }

   }

 

-  // pad spaces up to given width

-  if (!(flags & FLAGS_LEFT) && !(flags & FLAGS_ZEROPAD)) {

-    for (size_t i = len; i < width; i++) {

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

-    }

-  }

-

-  // reverse string

-  for (size_t i = 0U; i < len; i++) {

-    out(buf[len - i - 1U], buffer, idx++, maxlen);

-  }

-

-  // append pad spaces up to given width

-  if (flags & FLAGS_LEFT) {

-    while (idx - start_idx < width) {

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

-    }

-  }

-

-  return idx;

+  return _out_rev(out, buffer, idx, maxlen, buf, len, width, flags);

 }

 

 

@@ -319,8 +323,6 @@ static size_t _etoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, d
 

 static size_t _ftoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, double value, unsigned int prec, unsigned int width, unsigned int flags)

 {

-  const size_t start_idx = idx;

-

   char buf[PRINTF_FTOA_BUFFER_SIZE];

   size_t len  = 0U;

   double diff = 0.0;

@@ -330,10 +332,7 @@ static size_t _ftoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, d
 

   // test for NaN

   if (value != value) {

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

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

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

-    return idx;

+    return _out_rev(out, buffer, idx, maxlen, "nan", 3, width, flags);	// ensure value is padded as required

   }

 

   // test for very large values

@@ -445,26 +444,7 @@ static size_t _ftoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, d
     }

   }

 

-  // pad spaces up to given width

-  if (!(flags & FLAGS_LEFT) && !(flags & FLAGS_ZEROPAD)) {

-    for (size_t i = len; i < width; i++) {

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

-    }

-  }

-

-  // reverse string

-  for (size_t i = 0U; i < len; i++) {

-    out(buf[len - i - 1U], buffer, idx++, maxlen);

-  }

-

-  // append pad spaces up to given width

-  if (flags & FLAGS_LEFT) {

-    while (idx - start_idx < width) {

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

-    }

-  }

-

-  return idx;

+  return _out_rev(out, buffer, idx, maxlen, buf, len, width, flags);

 }

 

 #if defined(PRINTF_SUPPORT_EXPONENTIAL)