Wonders of roff(7): Integer numbers in numerical expressions can carry

scaling units, and some manuals (e.g. in devel/grcs) actually use that,
so let's support it.  Missing feature reported by naddy@.

5 files changed, 92 insertions, 7 deletions

diff --git a/regress/usr.bin/mandoc/roff/nr/Makefile b/regress/usr.bin/mandoc/roff/nr/Makefile
index e5b14f41098..8da6887869c 100644
--- a/regress/usr.bin/mandoc/roff/nr/Makefile
+++ b/regress/usr.bin/mandoc/roff/nr/Makefile
@@ -1,6 +1,6 @@
-# $OpenBSD: Makefile,v 1.8 2014/11/10 20:59:41 schwarze Exp $
+# $OpenBSD: Makefile,v 1.9 2015/01/23 00:38:43 schwarze Exp $
 
-REGRESS_TARGETS = argc divzero eval escname int predef rr
+REGRESS_TARGETS = argc divzero eval escname int predef rr scale
 LINT_TARGETS	= divzero escname
 
 .include <bsd.regress.mk>
diff --git a/regress/usr.bin/mandoc/roff/nr/scale.in b/regress/usr.bin/mandoc/roff/nr/scale.in
new file mode 100644
index 00000000000..6f63c589736
--- /dev/null
+++ b/regress/usr.bin/mandoc/roff/nr/scale.in
@@ -0,0 +1,26 @@
+.TH NR-INT 1 "January 23, 2015" OpenBSD
+.SH NAME
+nr-scale \- scaling units in numeric expressions
+.SH DESCRIPTION
+.nr Y 1f+1
+\nY
+.nr Y 1i+1
+\nY
+.nr Y 10c+1
+\nY
+.nr Y 1v+1
+\nY
+.nr Y 1P+1
+\nY
+.nr Y 1m+1
+\nY
+.nr Y 1n+1
+\nY
+.nr Y 10p+1
+\nY
+.nr Y 1u+1
+\nY
+.nr Y 100M+1
+\nY
+.nr Y 1X+2
+\nY
diff --git a/regress/usr.bin/mandoc/roff/nr/scale.out_ascii b/regress/usr.bin/mandoc/roff/nr/scale.out_ascii
new file mode 100644
index 00000000000..c6f79b2af8a
--- /dev/null
+++ b/regress/usr.bin/mandoc/roff/nr/scale.out_ascii
@@ -0,0 +1,13 @@
+NR-INT(1)                   General Commands Manual                  NR-INT(1)
+
+
+
+NNAAMMEE
+       nr-scale - scaling units in numeric expressions
+
+DDEESSCCRRIIPPTTIIOONN
+       65537 241 945 41 41 25 25 34 2 25 1
+
+
+
+OpenBSD                        January 23, 2015                      NR-INT(1)
diff --git a/share/man/man7/roff.7 b/share/man/man7/roff.7
index b670366b38b..b14dccdcc2a 100644
--- a/share/man/man7/roff.7
+++ b/share/man/man7/roff.7
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: roff.7,v 1.45 2015/01/21 23:48:05 jmc Exp $
+.\"	$OpenBSD: roff.7,v 1.46 2015/01/23 00:38:42 schwarze Exp $
 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010, 2011, 2013, 2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: January 21 2015 $
+.Dd $Mdocdate: January 23 2015 $
 .Dt ROFF 7
 .Os
 .Sh NAME
@@ -1713,6 +1713,14 @@ prefixed by an optional sign
 .Sq +
 or
 .Sq - .
+Each number may be followed by one optional scaling unit described below
+.Sx Scaling Widths .
+The following equations hold:
+.Bd -literal -offset indent
+1i = 6v = 6P = 10m = 10n = 72p = 1000M = 240u = 240
+254c = 100i = 24000u = 24000 
+1f = 65536u = 65536
+.Ed
 .Pp
 The following binary operators are implemented.
 Unless otherwise stated, they behave as in the C language:
diff --git a/usr.bin/mandoc/roff.c b/usr.bin/mandoc/roff.c
index 6e38f63443c..223cc407ff1 100644
--- a/usr.bin/mandoc/roff.c
+++ b/usr.bin/mandoc/roff.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: roff.c,v 1.125 2015/01/22 22:50:31 schwarze Exp $ */
+/*	$OpenBSD: roff.c,v 1.126 2015/01/23 00:38:42 schwarze Exp $ */
 /*
  * Copyright (c) 2010, 2011, 2012, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2015 Ingo Schwarze <schwarze@openbsd.org>
@@ -1639,8 +1639,46 @@ roff_getnum(const char *v, int *pos, int *res)
 	if (n)
 		*res = -*res;
 
-	*pos = p;
-	return 1;
+	/* Each number may be followed by one optional scaling unit. */
+
+	switch (v[p]) {
+	case 'f':
+		*res *= 65536;
+		break;
+	case 'i':
+		*res *= 240;
+		break;
+	case 'c':
+		*res *= 240;
+		*res /= 2.54;
+		break;
+	case 'v':
+		/* FALLTROUGH */
+	case 'P':
+		*res *= 40;
+		break;
+	case 'm':
+		/* FALLTROUGH */
+	case 'n':
+		*res *= 24;
+		break;
+	case 'p':
+		*res *= 10;
+		*res /= 3;
+		break;
+	case 'u':
+		break;
+	case 'M':
+		*res *= 6;
+		*res /= 25;
+		break;
+	default:
+		p--;
+		break;
+	}
+
+	*pos = p + 1;
+	return(1);
 }
 
 /*