1 files changed, 125 insertions, 0 deletions

diff --git a/src/lib/libc/stdlib/gcvt.c b/src/lib/libc/stdlib/gcvt.c
new file mode 100644
index 0000000000..d9081a7d39
--- /dev/null
+++ b/src/lib/libc/stdlib/gcvt.c
@@ -0,0 +1,125 @@
+/*      $OpenBSD: gcvt.c,v 1.12 2010/09/25 13:19:19 millert Exp $       */
+
+/*
+ * Copyright (c) 2002, 2003, 2006, 2010
+ *      Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Sponsored in part by the Defense Advanced Research Projects
+ * Agency (DARPA) and Air Force Research Laboratory, Air Force
+ * Materiel Command, USAF, under agreement number F39502-99-1-0512.
+ */
+
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+extern char *__dtoa(double, int, int, int *, int *, char **);
+extern void  __freedtoa(char *);
+
+#define DEFPREC 6
+
+char *
+gcvt(double value, int ndigit, char *buf)
+{
+        char *digits, *dst, *src;
+        int i, decpt, sign;
+        struct lconv *lconv;
+
+        lconv = localeconv();
+        if (ndigit <= 0) {
+                /* Match printf(3) behavior. */
+                ndigit = ndigit ? DEFPREC : 1;
+        }
+
+        digits = __dtoa(value, 2, ndigit, &decpt, &sign, NULL);
+        if (digits == NULL)
+                return (NULL);
+        if (decpt == 9999) {
+                /*
+                 * Infinity or NaN, convert to inf or nan with sign.
+                 * We can't infer buffer size based on ndigit.
+                 * We have to assume it is at least 5 chars.
+                 */
+                snprintf(buf, 5, "%s%s", sign ? "-" : "",
+                    *digits == 'I' ? "inf" : "nan");
+                __freedtoa(digits);
+                return (buf);
+        }
+
+        dst = buf;
+        if (sign)
+                *dst++ = '-';
+
+        /* Match printf(3) behavior for exponential vs. regular fomatting. */
+        if (decpt <= -4 || decpt > ndigit) {
+                /* exponential format (e.g. 1.2345e+13) */
+                if (--decpt < 0) {
+                        sign = 1;
+                        decpt = -decpt;
+                } else
+                        sign = 0;
+                src = digits;
+                *dst++ = *src++;
+                if (*src != '\0') {
+                        *dst++ = *lconv->decimal_point;
+                        do {
+                                *dst++ = *src++;
+                        } while (*src != '\0');
+                }
+                *dst++ = 'e';
+                if (sign)
+                        *dst++ = '-';
+                else
+                        *dst++ = '+';
+                if (decpt < 10) {
+                        *dst++ = '0';
+                        *dst++ = '0' + decpt;
+                        *dst = '\0';
+                } else {
+                        /* XXX - optimize */
+                        for (sign = decpt, i = 0; (sign /= 10) != 0; i++)
+                                continue;
+                        dst[i + 1] = '\0';
+                        while (decpt != 0) {
+                                dst[i--] = '0' + decpt % 10;
+                                decpt /= 10;
+                        }
+                }
+        } else {
+                /* standard format */
+                for (i = 0, src = digits; i < decpt; i++) {
+                        if (*src != '\0')
+                                *dst++ = *src++;
+                        else
+                                *dst++ = '0';
+                }
+                if (*src != '\0') {
+                        if (src == digits)
+                                *dst++ = '0';   /* zero before decimal point */
+                        *dst++ = *lconv->decimal_point;
+                        while (decpt < 0) {
+                                *dst++ = '0';
+                                decpt++;
+                        }
+                        for (i = decpt; digits[i] != '\0'; i++) {
+                                *dst++ = digits[i];
+                        }
+                }
+                *dst = '\0';
+        }
+        __freedtoa(digits);
+        return (buf);
+}