Replace our ancient dtoa/strtod implementation with the gdtoa

package, a more recent, generalized set of routines.  Among the
changes:
- Declare strtof() and strtold() in stdlib.h.
- Add glue to libc to support these routines for all kinds
  of ``long double''.
- Update printf() to reflect the fact that dtoa works slightly
  differently now.

As soon as I see that nothing has blown up, I will kill
src/lib/libc/stdlib/strtod.c.  Soon printf() will be able
to use the new routines to output long doubles without loss
of precision, but numerous bugs in the existing code must
be addressed first.

Reviewed by:	bde (briefly), mike (mentor), obrien

20 files changed, 286 insertions, 10 deletions

diff --git a/lib/libc/Makefile b/lib/libc/Makefile
index ae10f73..a6b8989 100644
--- a/lib/libc/Makefile
+++ b/lib/libc/Makefile
@@ -24,6 +24,13 @@ MDASM=
 MIASM=
 NOASM=
 
+# XXX Pull in contrib/netlib/gdtoa, but keep the filenames local to
+#     gdtoa out of libc.
+.PATH:	${.CURDIR}/../../contrib/netlib/gdtoa
+.include "${.CURDIR}/gdtoa/Makefile.inc"
+.PATH:
+.PATH: ${.CURDIR}/gdtoa
+
 #
 # If there is a machine dependent makefile, use it:
 #
diff --git a/lib/libc/alpha/arith.h b/lib/libc/alpha/arith.h
new file mode 100644
index 0000000..de6c33d
--- /dev/null
+++ b/lib/libc/alpha/arith.h
@@ -0,0 +1,13 @@
+/*
+ * MD header for contrib/netlib/gdtoa
+ *
+ * $FreeBSD$
+ */
+
+#define IEEE_8087
+#define Arith_Kind_ASL 1
+#define Long int
+#define Intcast (int)(long)
+#define Double_Align
+#define X64_bit_pointers
+#define Sudden_Underflow
diff --git a/lib/libc/alpha/stdlib/gdtoa.mk b/lib/libc/alpha/stdlib/gdtoa.mk
new file mode 100644
index 0000000..c631f64
--- /dev/null
+++ b/lib/libc/alpha/stdlib/gdtoa.mk
@@ -0,0 +1,4 @@
+# $FreeBSD$
+
+# On Alpha, long double is just double precision.
+MDSRCS+=machdep_ldisd.c
diff --git a/lib/libc/amd64/arith.h b/lib/libc/amd64/arith.h
new file mode 100644
index 0000000..d1bcfb6
--- /dev/null
+++ b/lib/libc/amd64/arith.h
@@ -0,0 +1,8 @@
+/*
+ * MD header for contrib/gdtoa
+ *
+ * $FreeBSD$
+ */
+
+#define IEEE_8087
+#define Arith_Kind_ASL 1
diff --git a/lib/libc/amd64/stdlib/gdtoa.mk b/lib/libc/amd64/stdlib/gdtoa.mk
new file mode 100644
index 0000000..50f2f0d
--- /dev/null
+++ b/lib/libc/amd64/stdlib/gdtoa.mk
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+# Long double is 80 bits
+GDTOASRCS+=strtopx.c
+MDSRCS+=machdep_ldisx.c
diff --git a/lib/libc/gdtoa/Makefile.inc b/lib/libc/gdtoa/Makefile.inc
new file mode 100644
index 0000000..c2c58e1
--- /dev/null
+++ b/lib/libc/gdtoa/Makefile.inc
@@ -0,0 +1,16 @@
+# $FreeBSD$
+
+CFLAGS+=-I${.CURDIR}/../../contrib/gdtoa
+MISRCS+=glue.c
+GDTOASRCS=dmisc.c dtoa.c gdtoa.c gethex.c gmisc.c \
+	hd_init.c hexnan.c misc.c smisc.c \
+	strtoIg.c strtod.c strtodg.c strtof.c strtord.c sum.c ulp.c
+.if exists(${.CURDIR}/${MACHINE_ARCH}/stdlib/gdtoa.mk)
+.include "${.CURDIR}/${MACHINE_ARCH}/stdlib/gdtoa.mk"
+.endif
+.for src in ${GDTOASRCS}
+MISRCS+=gdtoa_${src}
+CLEANFILES+=gdtoa_${src}
+gdtoa_${src}:
+	ln -sf ${.CURDIR}/../../contrib/gdtoa/${src} ${.TARGET}
+.endfor
diff --git a/lib/libc/gdtoa/glue.c b/lib/libc/gdtoa/glue.c
new file mode 100644
index 0000000..b587412
--- /dev/null
+++ b/lib/libc/gdtoa/glue.c
@@ -0,0 +1,10 @@
+/*
+ * Machine-independent glue to integrate David Gay's gdtoa
+ * package into libc.
+ *
+ * $FreeBSD$
+ */
+
+#include "spinlock.h"
+
+spinlock_t __gdtoa_locks[2];
diff --git a/lib/libc/gdtoa/machdep_ldisQ.c b/lib/libc/gdtoa/machdep_ldisQ.c
new file mode 100644
index 0000000..447b07f
--- /dev/null
+++ b/lib/libc/gdtoa/machdep_ldisQ.c
@@ -0,0 +1,45 @@
+/*-
+ * Copyright (c) 2003 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Machine-dependent glue to integrate David Gay's gdtoa
+ * package into libc for architectures where a long double
+ * uses quad precision, such as sparc64.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "gdtoaimp.h"
+
+long double
+strtold(const char * __restrict s, char ** __restrict sp)
+{
+	long double result;
+
+	strtopQ(s, sp, result);
+	return result;
+}
diff --git a/lib/libc/gdtoa/machdep_ldisd.c b/lib/libc/gdtoa/machdep_ldisd.c
new file mode 100644
index 0000000..e2dbb60
--- /dev/null
+++ b/lib/libc/gdtoa/machdep_ldisd.c
@@ -0,0 +1,43 @@
+/*-
+ * Copyright (c) 2003 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Machine-dependent glue to integrate David Gay's gdtoa
+ * package into libc for architectures where a long double
+ * is the same as a double, such as the Alpha.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "gdtoaimp.h"
+
+long double
+strtold(const char * __restrict s, char ** __restrict sp)
+{
+
+	return strtod(s, sp);
+}
diff --git a/lib/libc/gdtoa/machdep_ldisx.c b/lib/libc/gdtoa/machdep_ldisx.c
new file mode 100644
index 0000000..1920c39
--- /dev/null
+++ b/lib/libc/gdtoa/machdep_ldisx.c
@@ -0,0 +1,45 @@
+/*-
+ * Copyright (c) 2003 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Machine-dependent glue to integrate David Gay's gdtoa
+ * package into libc for architectures where a long double
+ * is an IEEE extended precision number.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "gdtoaimp.h"
+
+long double
+strtold(const char * __restrict s, char ** __restrict sp)
+{
+	long double result;
+
+	strtopx(s, sp, result);
+	return result;
+}
diff --git a/lib/libc/i386/arith.h b/lib/libc/i386/arith.h
new file mode 100644
index 0000000..d1bcfb6
--- /dev/null
+++ b/lib/libc/i386/arith.h
@@ -0,0 +1,8 @@
+/*
+ * MD header for contrib/gdtoa
+ *
+ * $FreeBSD$
+ */
+
+#define IEEE_8087
+#define Arith_Kind_ASL 1
diff --git a/lib/libc/i386/stdlib/gdtoa.mk b/lib/libc/i386/stdlib/gdtoa.mk
new file mode 100644
index 0000000..50f2f0d
--- /dev/null
+++ b/lib/libc/i386/stdlib/gdtoa.mk
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+# Long double is 80 bits
+GDTOASRCS+=strtopx.c
+MDSRCS+=machdep_ldisx.c
diff --git a/lib/libc/ia64/arith.h b/lib/libc/ia64/arith.h
new file mode 100644
index 0000000..9102826
--- /dev/null
+++ b/lib/libc/ia64/arith.h
@@ -0,0 +1,30 @@
+/*
+ * MD header for contrib/gdtoa
+ *
+ * $FreeBSD$
+ */
+
+#include <machine/endian.h>
+
+#if _BYTE_ORDER == _LITTLE_ENDIAN
+
+#define IEEE_8087
+#define Arith_Kind_ASL 1
+#define Long int
+#define Intcast (int)(long)
+#define Double_Align
+#define X64_bit_pointers
+
+#else /* _BYTE_ORDER == _LITTLE_ENDIAN */
+
+#define IEEE_MC68k
+#define Arith_Kind_ASL 2
+#define Long int
+#define Intcast (int)(long)
+#define Double_Align
+#define X64_bit_pointers
+#ifdef gcc_bug	/* XXX Why does arithchk report sudden underflow here? */
+#define Sudden_Underflow
+#endif
+
+#endif
diff --git a/lib/libc/ia64/stdlib/gdtoa.mk b/lib/libc/ia64/stdlib/gdtoa.mk
new file mode 100644
index 0000000..50f2f0d
--- /dev/null
+++ b/lib/libc/ia64/stdlib/gdtoa.mk
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+# Long double is 80 bits
+GDTOASRCS+=strtopx.c
+MDSRCS+=machdep_ldisx.c
diff --git a/lib/libc/powerpc/arith.h b/lib/libc/powerpc/arith.h
new file mode 100644
index 0000000..9f4cfe4
--- /dev/null
+++ b/lib/libc/powerpc/arith.h
@@ -0,0 +1,9 @@
+/*
+ * MD header for contrib/gdtoa
+ *
+ * $FreeBSD$
+ */
+
+#define IEEE_MC68k
+#define Arith_Kind_ASL 2
+#define Double_Align
diff --git a/lib/libc/powerpc/stdlib/gdtoa.mk b/lib/libc/powerpc/stdlib/gdtoa.mk
new file mode 100644
index 0000000..f951a8d
--- /dev/null
+++ b/lib/libc/powerpc/stdlib/gdtoa.mk
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+# Long double is quad precision
+GDTOASRCS+=strtopQ.c
+MDSRCS+=machdep_ldisQ.c
diff --git a/lib/libc/sparc64/arith.h b/lib/libc/sparc64/arith.h
new file mode 100644
index 0000000..c954a9c
--- /dev/null
+++ b/lib/libc/sparc64/arith.h
@@ -0,0 +1,12 @@
+/*
+ * MD header for contrib/gdtoa
+ *
+ * $FreeBSD$
+ */
+
+#define IEEE_MC68k
+#define Arith_Kind_ASL 2
+#define Long int
+#define Intcast (int)(long)
+#define Double_Align
+#define X64_bit_pointers
diff --git a/lib/libc/sparc64/stdlib/gdtoa.mk b/lib/libc/sparc64/stdlib/gdtoa.mk
new file mode 100644
index 0000000..f951a8d
--- /dev/null
+++ b/lib/libc/sparc64/stdlib/gdtoa.mk
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+# Long double is quad precision
+GDTOASRCS+=strtopQ.c
+MDSRCS+=machdep_ldisQ.c
diff --git a/lib/libc/stdio/vfprintf.c b/lib/libc/stdio/vfprintf.c
index b0084c8..460d416 100644
--- a/lib/libc/stdio/vfprintf.c
+++ b/lib/libc/stdio/vfprintf.c
@@ -413,7 +413,10 @@ vfprintf(FILE * __restrict fp, const char * __restrict fmt0, va_list ap)
 #define	BUF		((MAXEXP*2)+MAXFRACT+1)		/* + decimal point */
 #define	DEFPREC		6
 
-static char *cvt(double, int, int, char *, int *, int, int *, char **);
+extern char *__dtoa(double, int, int, int *, int *, char **);
+extern void __freedtoa(char *s);
+
+static char *cvt(double, int, int, char *, int *, int, int *);
 static int exponent(char *, int, int);
 
 #else /* no FLOATING_POINT */
@@ -840,11 +843,11 @@ fp_begin:		if (prec == -1)
 			}
 			flags |= FPT;
 			if (dtoaresult != NULL) {
-				free(dtoaresult);
+				__freedtoa(dtoaresult);
 				dtoaresult = NULL;
 			}
-			cp = cvt(_double, prec, flags, &softsign,
-				&expt, ch, &ndig, &dtoaresult);
+			dtoaresult = cp = cvt(_double, prec, flags, &softsign,
+				&expt, ch, &ndig);
 			if (ch == 'g' || ch == 'G') {
 				if (expt <= -4 || expt > prec)
 					ch = (ch == 'g') ? 'e' : 'E';
@@ -1138,7 +1141,7 @@ done:
 error:
 #ifdef FLOATING_POINT
 	if (dtoaresult != NULL)
-		free(dtoaresult);
+		__freedtoa(dtoaresult);
 #endif
 	if (convbuf != NULL)
 		free(convbuf);
@@ -1508,11 +1511,9 @@ __grow_type_table (int nextarg, enum typeid **typetable, int *tablesize)
 
 #ifdef FLOATING_POINT
 
-extern char *__dtoa(double, int, int, int *, int *, char **, char **);
-
 static char *
 cvt(double value, int ndigits, int flags, char *sign, int *decpt,
-    int ch, int *length, char **dtoaresultp)
+    int ch, int *length)
 {
 	int mode, dsgn;
 	char *digits, *bp, *rve;
@@ -1529,7 +1530,7 @@ cvt(double value, int ndigits, int flags, char *sign, int *decpt,
 			ndigits++;
 		mode = 2;		/* ndigits significant digits */
 	}
-	digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve, dtoaresultp);
+	digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve);
 	*sign = dsgn != 0;
 	if ((ch != 'g' && ch != 'G') || flags & ALT) {
 		/* print trailing zeros */
diff --git a/lib/libc/stdlib/Makefile.inc b/lib/libc/stdlib/Makefile.inc
index 92c3d29..265aae1 100644
--- a/lib/libc/stdlib/Makefile.inc
+++ b/lib/libc/stdlib/Makefile.inc
@@ -9,7 +9,7 @@ MISRCS+=_Exit.c abort.c abs.c atexit.c atof.c atoi.c atol.c atoll.c \
 	getsubopt.c grantpt.c hcreate.c heapsort.c imaxabs.c imaxdiv.c \
 	insque.c labs.c ldiv.c llabs.c lldiv.c lsearch.c malloc.c merge.c \
 	putenv.c qsort.c qsort_r.c radixsort.c rand.c random.c reallocf.c \
-	realpath.c remque.c setenv.c strfmon.c strhash.c strtod.c strtoimax.c \
+	realpath.c remque.c setenv.c strfmon.c strhash.c strtoimax.c \
 	strtol.c strtoll.c strtoq.c strtoul.c strtoull.c strtoumax.c strtouq.c \
 	system.c tdelete.c tfind.c tsearch.c twalk.c