[2/2] Fix gcvt to always show 'ndigits' of precision

Message ID 20191218164906.1124916-2-keithp@keithp.com
State Accepted
Commit 11f99384d2971356bab2fcac7e29792250abea73
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Series
  • [1/2] Fix fcvt to only show 'ndigit' past decimal
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Commit Message

Keith Packard Dec. 18, 2019, 4:49 p.m.
Leading zeros after the decimal point should not count
towards the 'ndigits' limit.

This makes gcvt match glibc and the posix gcvt man page.

Signed-off-by: Keith Packard <keithp@keithp.com>

---
 newlib/libc/stdlib/ecvtbuf.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

-- 
2.24.0

Patch

diff --git a/newlib/libc/stdlib/ecvtbuf.c b/newlib/libc/stdlib/ecvtbuf.c
index 12e8c9a92..228362e07 100644
--- a/newlib/libc/stdlib/ecvtbuf.c
+++ b/newlib/libc/stdlib/ecvtbuf.c
@@ -349,15 +349,10 @@  _gcvt (struct _reent *ptr,
       char *end;
       char *p;
 
-      if (invalue < 1.0)
-	{
-	  /* what we want is ndigits after the point */
-	  p = _dtoa_r (ptr, invalue, 3, ndigit, &decpt, &sign, &end);
-	}
-      else
-	{
-	  p = _dtoa_r (ptr, invalue, 2, ndigit, &decpt, &sign, &end);
-	}
+      /* We always want ndigits of precision, even if that means printing
+       * a bunch of leading zeros for numbers < 1.0
+       */
+      p = _dtoa_r (ptr, invalue, 2, ndigit, &decpt, &sign, &end);
 
       if (decpt == 9999)
 	{
@@ -383,11 +378,12 @@  _gcvt (struct _reent *ptr,
 	  if (buf == save)
 	    *buf++ = '0';
 	  *buf++ = '.';
-	  while (decpt < 0 && ndigit > 0)
+
+	  /* Leading zeros don't count towards 'ndigit' */
+	  while (decpt < 0)
 	    {
 	      *buf++ = '0';
 	      decpt++;
-	      ndigit--;
 	    }
 
 	  /* Print rest of stuff */