make __dtoa & strtod() thread-safe useing the same method as newer gdtoa

codebase.  tested mostly by ckuethe and myself.  __dtoa() use now requires
a call to __freedtoa()

1 files changed, 10 insertions, 4 deletions

diff --git a/src/lib/libc/stdlib/ecvt.c b/src/lib/libc/stdlib/ecvt.c
index eb0e428996..719370a8f3 100644
--- a/src/lib/libc/stdlib/ecvt.c
+++ b/src/lib/libc/stdlib/ecvt.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: ecvt.c,v 1.5 2006/01/10 16:18:37 millert Exp $        */
+/*      $OpenBSD: ecvt.c,v 1.6 2006/10/29 18:45:56 deraadt Exp $        */
 
 /*
  * Copyright (c) 2002, 2006 Todd C. Miller <Todd.Miller@courtesan.com>
@@ -25,13 +25,14 @@
 #include <string.h>
 
 extern char *__dtoa(double, int, int, int *, int *, char **);
+extern void  __freedtoa(char *);
 static char *__cvt(double, int, int *, int *, int, int);
 
 static char *
 __cvt(double value, int ndigit, int *decpt, int *sign, int fmode, int pad)
 {
         static char *s;
-        char *p, *rve;
+        char *p, *rve, c;
         size_t siz;
 
         if (ndigit == 0) {
@@ -64,15 +65,20 @@ __cvt(double value, int ndigit, int *decpt, int *sign, int fmode, int pad)
                 if (*decpt == 9999) {
                         /* Infinity or Nan, convert to inf or nan like printf */
                         *decpt = 0;
-                        return(*p == 'I' ? "inf" : "nan");
+                        c = *p;
+                        __freedtoa(p);
+                        return(c == 'I' ? "inf" : "nan");
                 }
                 /* Make a local copy and adjust rve to be in terms of s */
                 if (pad && fmode)
                         siz += *decpt;
-                if ((s = (char *)malloc(siz)) == NULL)
+                if ((s = (char *)malloc(siz)) == NULL) {
+                        __freedtoa(p);
                         return(NULL);
+                }
                 (void) strlcpy(s, p, siz);
                 rve = s + (rve - p);
+                __freedtoa(p);
         }
 
         /* Add trailing zeros */