_ecvt:

- Rewrite the function, getting rid of alloca and unneeded code parts
- Relies on working sprintf, especially allows to detect the decimal point position independent of wanted precision
- Fixes all msvcrt printf winetests

svn path=/trunk/; revision=42383

reactos/lib/sdk/crt/crt.rbuild

@@ -317,7 +317,6 @@
 		<file>abort.c</file>
 		<file>atexit.c</file>
 		<file>ecvt.c</file>
-		<file>ecvtbuf.c</file>
 		<file>errno.c</file>
 		<file>fcvt.c</file>
 		<file>fcvtbuf.c</file>

reactos/lib/sdk/crt/stdlib/ecvt.c

@@ -1,7 +1,12 @@
-/* Copyright (C) 1998 DJ Delorie, see COPYING.DJ for details */
-#include <precomp.h>
+/*
+ * PROJECT:         ReactOS CRT
+ * LICENSE:         See COPYING in the top level directory
+ * PURPOSE:         CRT's ecvt
+ * FILE:            lib/sdk/crt/stdlib/ecvt.c
+ * PROGRAMERS:      Gregor Schneider (parts based on ecvtbuf.c by DJ Delorie)
+ */
 
-char *ecvtbuf (double, int, int *, int *, char *);
+#include <precomp.h>
 
 /*
  * @implemented
@@ -9,6 +14,98 @@ char *ecvtbuf (double, int, int *, int *, char *);
 char *
 _ecvt (double value, int ndigits, int *decpt, int *sign)
 {
-  static char ecvt_buf[DBL_MAX_10_EXP + 10];
-  return ecvtbuf (value, ndigits, decpt, sign, ecvt_buf);
+  char *ecvtbuf, *cvtbuf;
+  char *s, *d;
+
+  s = cvtbuf = (char*)malloc(ndigits + 18); /* sign, dot, null, 15 for alignment */
+  d = ecvtbuf = (char*)malloc(DBL_MAX_10_EXP + 10);
+
+  *sign = 0;
+  *decpt = 0;
+
+  if (cvtbuf == NULL || ecvtbuf == NULL)
+  {
+    return NULL;
+  }
+
+  sprintf(cvtbuf, "%-+.*E", ndigits, value);
+  /* Treat special values */
+  if (strncmp(s, "NaN", 3) == 0)
+  {
+    memcpy(ecvtbuf, s, 4);
+  }
+  else if (strncmp(s + 1, "Inf", 3) == 0)
+  {
+    memcpy(ecvtbuf, s, 5);
+  }
+  else 
+  {
+    /* Set the sign */
+    if (*s && *s == '-')
+    {
+      *sign = 1;
+    }
+    s++;
+    /* Copy the first digit */
+    if (*s && *s != '.')
+    {
+      if (d - ecvtbuf < ndigits)
+      {
+        *d++ = *s++;
+      }
+      else
+      {
+        s++;
+      }
+    }
+    /* Skip the decimal point */
+    if (*s && *s == '.')
+    {
+      s++;
+    }
+    /* Copy fractional digits */
+    while (*s && *s != 'E')
+    {
+      if (d - ecvtbuf < ndigits)
+      {
+        *d++ = *s++;
+      }
+      else
+      {
+        s++;
+      }
+    }
+    /* Skip the exponent */
+    if (*s && *s == 'E')
+    {
+      s++;
+    }
+    /* Set the decimal point to the exponent value plus the one digit we copied */
+    *decpt = atoi(s) + 1;
+    /* Handle special decimal point cases */
+    if (cvtbuf[1] == '0')
+    {
+      *decpt = 0;
+    }
+    if (ndigits < 1)
+    {
+      /* Need enhanced precision*/
+      char* tbuf = (char*)malloc(ndigits + 18);
+      sprintf(tbuf, "%-+.*E", ndigits + 2, value);
+      if (tbuf[1] >= '5')
+      {
+        (*decpt)++;
+      }
+      free(tbuf);
+    }
+    /* Pad with zeroes */
+    while (d - ecvtbuf < ndigits)
+    {
+      *d++ = '0';
+    }
+    /* Terminate */
+    *d = '\0';
+  }
+  free(cvtbuf);
+  return ecvtbuf;
 }

reactos/lib/sdk/crt/stdlib/ecvtbuf.c

@@ -1,108 +0,0 @@
-/* Copyright (C) 1998 DJ Delorie, see COPYING.DJ for details */
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <float.h>
-#include <malloc.h>
-// #include <msvcrt/locale.h>
-
-void __ecvround (char *, char *, const char *, int *);
-
-void
-__ecvround (char *numbuf, char *last_digit, const char *after_last, int *decpt)
-{
-  char *p;
-  int carry = 0;
-
-  /* Do we have at all to round the last digit?  */
-  if (*after_last > '4')
-    {
-      p = last_digit;
-      carry = 1;
-
-      /* Propagate the rounding through trailing '9' digits.  */
-      do {
-	int sum = *p + carry;
-	carry = sum > '9';
-	*p-- = sum - carry * 10;
-      } while (carry && p >= numbuf);
-
-      /* We have 9999999... which needs to be rounded to 100000..  */
-      if (carry && p == numbuf)
-	{
-	  *p = '1';
-	  *decpt += 1;
-	}
-    }
-}
-
-char *
-ecvtbuf (double value, int ndigits, int *decpt, int *sign, char *buf)
-{
-  static char INFINITY[] = "Infinity";
-  char decimal = '.' /* localeconv()->decimal_point[0] */;
-  char *cvtbuf = (char *)_alloca (ndigits + 20); /* +3 for sign, dot, null; */
-					        /* two extra for rounding */
-						/* 15 extra for alignment */
-  char *s = cvtbuf, *d = buf;
-
-  /* Produce two extra digits, so we could round properly.  */
-  sprintf (cvtbuf, "%-+.*E", ndigits + 2, value);
-  *decpt = 0;
-
-  /* The sign.  */
-  if (*s++ == '-')
-    *sign = 1;
-  else
-    *sign = 0;
-
-  /* Special values get special treatment.  */
-  if (strncmp (s, "Inf", 3) == 0)
-    {
-      /* SunOS docs says we have return "Infinity" for NDIGITS >= 8.  */
-      memcpy (buf, INFINITY, ndigits >= 8 ? 9 : 3);
-      if (ndigits < 8)
-	buf[3] = '\0';
-    }
-  else if (strcmp (s, "NaN") == 0)
-    memcpy (buf, s, 4);
-  else
-    {
-      char *last_digit, *digit_after_last;
-
-      /* Copy (the single) digit before the decimal.  */
-      while (*s && *s != decimal && d - buf < ndigits)
-	*d++ = *s++;
-
-      /* If we don't see any exponent, here's our decimal point.  */
-      *decpt = d - buf;
-      if (*s)
-	s++;
-
-      /* Copy the fraction digits.  */
-      while (*s && *s != 'E' && d - buf < ndigits)
-	*d++ = *s++;
-
-      /* Remember the last digit copied and the one after it.  */
-      last_digit = d > buf ? d - 1 : d;
-      digit_after_last = s;
-
-      /* Get past the E in exponent field.  */
-      while (*s && *s++ != 'E')
-	;
-
-      /* Adjust the decimal point by the exponent value.  */
-      *decpt += atoi (s);
-
-      /* Pad with zeroes if needed.  */
-      while (d - buf < ndigits)
-	*d++ = '0';
-
-      /* Zero-terminate.  */
-      *d = '\0';
-
-      /* Round if necessary.  */
-      __ecvround (buf, last_digit, digit_after_last, decpt);
-    }
-  return buf;
-}