initial import of NetBSD tree

3 files changed, 760 insertions, 0 deletions

diff --git a/usr.bin/checknr/Makefile b/usr.bin/checknr/Makefile
new file mode 100644
index 00000000000..0c107ae30d2
--- /dev/null
+++ b/usr.bin/checknr/Makefile
@@ -0,0 +1,6 @@
+#	$NetBSD: Makefile,v 1.3 1995/03/26 04:10:08 glass Exp $
+#	@(#)Makefile	8.1 (Berkeley) 6/6/93
+
+PROG=	checknr
+
+.include <bsd.prog.mk>
diff --git a/usr.bin/checknr/checknr.1 b/usr.bin/checknr/checknr.1
new file mode 100644
index 00000000000..1074000c796
--- /dev/null
+++ b/usr.bin/checknr/checknr.1
@@ -0,0 +1,161 @@
+.\"	$NetBSD: checknr.1,v 1.5 1995/03/26 04:10:14 glass Exp $
+.\"
+.\" Copyright (c) 1980, 1990, 1993
+.\"	The Regents of the University of California.  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.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+.\"
+.\"     @(#)checknr.1	8.1 (Berkeley) 6/6/93
+.\"
+.Dd June 6, 1993
+.Dt CHECKNR 1
+.Os BSD 4
+.Sh NAME
+.Nm checknr
+.Nd check nroff/troff files
+.Sh SYNOPSIS
+.Nm checknr
+.Op Fl a Ns Ar \&.x1.y1.x2.y2. ... \&.xn.yn
+.Op Fl c Ns Ar \&.x1.x2.x3 ... \&.xn
+.Op Fl s
+.Op Fl f
+.Ar file
+.Sh DESCRIPTION
+.Nm Checknr
+checks a list of
+.Xr nroff 1
+or
+.Xr troff 1
+input files for certain kinds of errors
+involving mismatched opening and closing delimiters
+and unknown commands.
+If no files are specified,
+.Nm checknr
+checks the standard input.
+.Pp
+Options:
+.Bl -tag -width Ds
+.It Fl a
+Add additional pairs of macros to the list of known macros.
+This must be followed by groups of six characters, each group defining
+a pair of macros.
+The six characters are
+a period,
+the first macro name,
+another period,
+and the second macro name.
+For example, to define a pair .BS and .ES, use
+.Sq Li \-a.BS.ES
+.It Fl c
+Define commands which would otherwise be complained about
+as undefined.
+.It Fl f
+Request
+.Nm checknr
+to ignore
+.Ql \ef
+font changes.
+.It Fl s
+Ignore
+.Ql \es
+size changes.
+.El
+.Pp
+Delimiters checked are:
+.Bl -enum
+.It
+Font changes using \efx ... \efP.
+.It
+Size changes using \esx ... \es0.
+.It
+Macros that come in open ... close forms, for example,
+the .TS and .TE macros which must always come in pairs.
+.El
+.Pp
+.Nm Checknr
+is intended for use on documents that are prepared with
+.Nm checknr
+in mind, much the same as
+.Xr lint 1 .
+It expects a certain document writing style for
+.Ql \ef
+and
+.Ql \es
+commands,
+in that each
+.Ql \efx
+must be terminated with
+.Ql \efP
+and
+each
+.Ql \esx
+must be terminated with
+.Ql \es0 .
+While it will work to directly go into the next font or explicitly
+specify the original font or point size,
+and many existing documents actually do this,
+such a practice will produce complaints from
+.Nm checknr .
+Since it is probably better to use the
+.Ql \efP
+and
+.Ql \es0
+forms anyway,
+you should think of this as a contribution to your document
+preparation style.
+.Pp
+.Nm Checknr
+knows about the
+.Xr ms 7
+and
+.Xr me 7
+macro packages.
+.Sh SEE ALSO
+.Xr nroff 1 ,
+.Xr troff 1 ,
+.Xr checkeq 1 ,
+.Xr ms 7 ,
+.Xr me 7
+.Sh DIAGNOSTICS
+.Bd -ragged -compact
+Complaints about unmatched delimiters.
+Complaints about unrecognized commands.
+Various complaints about the syntax of commands.
+.Ed
+.Sh BUGS
+There is no way to define a 1 character macro name using
+.Fl a .
+.Pp
+Does not correctly recognize certain reasonable constructs,
+such as conditionals.
+.Sh HISTORY
+The
+.Nm
+command appeared in 
+.Bx 4.0 .
diff --git a/usr.bin/checknr/checknr.c b/usr.bin/checknr/checknr.c
new file mode 100644
index 00000000000..e9f19ce819b
--- /dev/null
+++ b/usr.bin/checknr/checknr.c
@@ -0,0 +1,593 @@
+/*	$NetBSD: checknr.c,v 1.4 1995/03/26 04:10:19 glass Exp $	*/
+
+/*
+ * Copyright (c) 1980, 1993
+ *	The Regents of the University of California.  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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ */
+
+#ifndef lint
+static char copyright[] =
+"@(#) Copyright (c) 1980, 1993\n\
+	The Regents of the University of California.  All rights reserved.\n";
+#endif /* not lint */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)checknr.c	8.1 (Berkeley) 6/6/93";
+#else 
+static char rcsid[] = "$NetBSD: checknr.c,v 1.4 1995/03/26 04:10:19 glass Exp $";
+#endif
+#endif /* not lint */
+
+/*
+ * checknr: check an nroff/troff input file for matching macro calls.
+ * we also attempt to match size and font changes, but only the embedded
+ * kind.  These must end in \s0 and \fP resp.  Maybe more sophistication
+ * later but for now think of these restrictions as contributions to
+ * structured typesetting.
+ */
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+
+#define MAXSTK	100	/* Stack size */
+#define MAXBR	100	/* Max number of bracket pairs known */
+#define MAXCMDS	500	/* Max number of commands known */
+
+/*
+ * The stack on which we remember what we've seen so far.
+ */
+struct stkstr {
+	int opno;	/* number of opening bracket */
+	int pl;		/* '+', '-', ' ' for \s, 1 for \f, 0 for .ft */
+	int parm;	/* parm to size, font, etc */
+	int lno;	/* line number the thing came in in */
+} stk[MAXSTK];
+int stktop;
+
+/*
+ * The kinds of opening and closing brackets.
+ */
+struct brstr {
+	char *opbr;
+	char *clbr;
+} br[MAXBR] = {
+	/* A few bare bones troff commands */
+#define SZ	0
+	"sz",	"sz",	/* also \s */
+#define FT	1
+	"ft",	"ft",	/* also \f */
+	/* the -mm package */
+	"AL",	"LE",
+	"AS",	"AE",
+	"BL",	"LE",
+	"BS",	"BE",
+	"DF",	"DE",
+	"DL",	"LE",
+	"DS",	"DE",
+	"FS",	"FE",
+	"ML",	"LE",
+	"NS",	"NE",
+	"RL",	"LE",
+	"VL",	"LE",
+	/* the -ms package */
+	"AB",	"AE",
+	"BD",	"DE",
+	"CD",	"DE",
+	"DS",	"DE",
+	"FS",	"FE",
+	"ID",	"DE",
+	"KF",	"KE",
+	"KS",	"KE",
+	"LD",	"DE",
+	"LG",	"NL",
+	"QS",	"QE",
+	"RS",	"RE",
+	"SM",	"NL",
+	"XA",	"XE",
+	"XS",	"XE",
+	/* The -me package */
+	"(b",	")b",
+	"(c",	")c",
+	"(d",	")d",
+	"(f",	")f",
+	"(l",	")l",
+	"(q",	")q",
+	"(x",	")x",
+	"(z",	")z",
+	/* Things needed by preprocessors */
+	"EQ",	"EN",
+	"TS",	"TE",
+	/* Refer */
+	"[",	"]",
+	0,	0
+};
+
+/*
+ * All commands known to nroff, plus macro packages.
+ * Used so we can complain about unrecognized commands.
+ */
+char *knowncmds[MAXCMDS] = {
+"$c", "$f", "$h", "$p", "$s", "(b", "(c", "(d", "(f", "(l", "(q", "(t",
+"(x", "(z", ")b", ")c", ")d", ")f", ")l", ")q", ")t", ")x", ")z", "++",
+"+c", "1C", "1c", "2C", "2c", "@(", "@)", "@C", "@D", "@F", "@I", "@M",
+"@c", "@e", "@f", "@h", "@m", "@n", "@o", "@p", "@r", "@t", "@z", "AB",
+"AE", "AF", "AI", "AL", "AM", "AS", "AT", "AU", "AX", "B",  "B1", "B2",
+"BD", "BE", "BG", "BL", "BS", "BT", "BX", "C1", "C2", "CD", "CM", "CT",
+"D",  "DA", "DE", "DF", "DL", "DS", "DT", "EC", "EF", "EG", "EH", "EM",
+"EN", "EQ", "EX", "FA", "FD", "FE", "FG", "FJ", "FK", "FL", "FN", "FO",
+"FQ", "FS", "FV", "FX", "H",  "HC", "HD", "HM", "HO", "HU", "I",  "ID",
+"IE", "IH", "IM", "IP", "IX", "IZ", "KD", "KE", "KF", "KQ", "KS", "LB",
+"LC", "LD", "LE", "LG", "LI", "LP", "MC", "ME", "MF", "MH", "ML", "MR",
+"MT", "ND", "NE", "NH", "NL", "NP", "NS", "OF", "OH", "OK", "OP", "P",
+"P1", "PF", "PH", "PP", "PT", "PX", "PY", "QE", "QP", "QS", "R",  "RA",
+"RC", "RE", "RL", "RP", "RQ", "RS", "RT", "S",  "S0", "S2", "S3", "SA",
+"SG", "SH", "SK", "SM", "SP", "SY", "T&", "TA", "TB", "TC", "TD", "TE",
+"TH", "TL", "TM", "TP", "TQ", "TR", "TS", "TX", "UL", "US", "UX", "VL",
+"WC", "WH", "XA", "XD", "XE", "XF", "XK", "XP", "XS", "[",  "[-", "[0",
+"[1", "[2", "[3", "[4", "[5", "[<", "[>", "[]", "]",  "]-", "]<", "]>",
+"][", "ab", "ac", "ad", "af", "am", "ar", "as", "b",  "ba", "bc", "bd",
+"bi", "bl", "bp", "br", "bx", "c.", "c2", "cc", "ce", "cf", "ch", "cs",
+"ct", "cu", "da", "de", "di", "dl", "dn", "ds", "dt", "dw", "dy", "ec",
+"ef", "eh", "el", "em", "eo", "ep", "ev", "ex", "fc", "fi", "fl", "fo",
+"fp", "ft", "fz", "hc", "he", "hl", "hp", "ht", "hw", "hx", "hy", "i",
+"ie", "if", "ig", "in", "ip", "it", "ix", "lc", "lg", "li", "ll", "ln",
+"lo", "lp", "ls", "lt", "m1", "m2", "m3", "m4", "mc", "mk", "mo", "n1",
+"n2", "na", "ne", "nf", "nh", "nl", "nm", "nn", "np", "nr", "ns", "nx",
+"of", "oh", "os", "pa", "pc", "pi", "pl", "pm", "pn", "po", "pp", "ps",
+"q",  "r",  "rb", "rd", "re", "rm", "rn", "ro", "rr", "rs", "rt", "sb",
+"sc", "sh", "sk", "so", "sp", "ss", "st", "sv", "sz", "ta", "tc", "th",
+"ti", "tl", "tm", "tp", "tr", "u",  "uf", "uh", "ul", "vs", "wh", "xp",
+"yr", 0
+};
+
+int	lineno;		/* current line number in input file */
+char	line[256];	/* the current line */
+char	*cfilename;	/* name of current file */
+int	nfiles;		/* number of files to process */
+int	fflag;		/* -f: ignore \f */
+int	sflag;		/* -s: ignore \s */
+int	ncmds;		/* size of knowncmds */
+int	slot;		/* slot in knowncmds found by binsrch */
+
+char	*malloc();
+
+main(argc, argv)
+int argc;
+char **argv;
+{
+	FILE *f;
+	int i;
+	char *cp;
+	char b1[4];
+
+	/* Figure out how many known commands there are */
+	while (knowncmds[ncmds])
+		ncmds++;
+	while (argc > 1 && argv[1][0] == '-') {
+		switch(argv[1][1]) {
+
+		/* -a: add pairs of macros */
+		case 'a':
+			i = strlen(argv[1]) - 2;
+			if (i % 6 != 0)
+				usage();
+			/* look for empty macro slots */
+			for (i=0; br[i].opbr; i++)
+				;
+			for (cp=argv[1]+3; cp[-1]; cp += 6) {
+				br[i].opbr = malloc(3);
+				strncpy(br[i].opbr, cp, 2);
+				br[i].clbr = malloc(3);
+				strncpy(br[i].clbr, cp+3, 2);
+				addmac(br[i].opbr);	/* knows pairs are also known cmds */
+				addmac(br[i].clbr);
+				i++;
+			}
+			break;
+
+		/* -c: add known commands */
+		case 'c':
+			i = strlen(argv[1]) - 2;
+			if (i % 3 != 0)
+				usage();
+			for (cp=argv[1]+3; cp[-1]; cp += 3) {
+				if (cp[2] && cp[2] != '.')
+					usage();
+				strncpy(b1, cp, 2);
+				addmac(b1);
+			}
+			break;
+
+		/* -f: ignore font changes */
+		case 'f':
+			fflag = 1;
+			break;
+
+		/* -s: ignore size changes */
+		case 's':
+			sflag = 1;
+			break;
+		default:
+			usage();
+		}
+		argc--; argv++;
+	}
+
+	nfiles = argc - 1;
+
+	if (nfiles > 0) {
+		for (i=1; i<argc; i++) {
+			cfilename = argv[i];
+			f = fopen(cfilename, "r");
+			if (f == NULL)
+				perror(cfilename);
+			else
+				process(f);
+		}
+	} else {
+		cfilename = "stdin";
+		process(stdin);
+	}
+	exit(0);
+}
+
+usage()
+{
+	printf("Usage: checknr -s -f -a.xx.yy.xx.yy... -c.xx.xx.xx...\n");
+	exit(1);
+}
+
+process(f)
+FILE *f;
+{
+	register int i, n;
+	char mac[5];	/* The current macro or nroff command */
+	int pl;
+
+	stktop = -1;
+	for (lineno = 1; fgets(line, sizeof line, f); lineno++) {
+		if (line[0] == '.') {
+			/*
+			 * find and isolate the macro/command name.
+			 */
+			strncpy(mac, line+1, 4);
+			if (isspace(mac[0])) {
+				pe(lineno);
+				printf("Empty command\n");
+			} else if (isspace(mac[1])) {
+				mac[1] = 0;
+			} else if (isspace(mac[2])) {
+				mac[2] = 0;
+			} else if (mac[0] != '\\' || mac[1] != '\"') {
+				pe(lineno);
+				printf("Command too long\n");
+			}
+
+			/*
+			 * Is it a known command?
+			 */
+			checkknown(mac);
+
+			/*
+			 * Should we add it?
+			 */
+			if (eq(mac, "de"))
+				addcmd(line);
+
+			chkcmd(line, mac);
+		}
+
+		/*
+		 * At this point we process the line looking
+		 * for \s and \f.
+		 */
+		for (i=0; line[i]; i++)
+			if (line[i]=='\\' && (i==0 || line[i-1]!='\\')) {
+				if (!sflag && line[++i]=='s') {
+					pl = line[++i];
+					if (isdigit(pl)) {
+						n = pl - '0';
+						pl = ' ';
+					} else
+						n = 0;
+					while (isdigit(line[++i]))
+						n = 10 * n + line[i] - '0';
+					i--;
+					if (n == 0) {
+						if (stk[stktop].opno == SZ) {
+							stktop--;
+						} else {
+							pe(lineno);
+							printf("unmatched \\s0\n");
+						}
+					} else {
+						stk[++stktop].opno = SZ;
+						stk[stktop].pl = pl;
+						stk[stktop].parm = n;
+						stk[stktop].lno = lineno;
+					}
+				} else if (!fflag && line[i]=='f') {
+					n = line[++i];
+					if (n == 'P') {
+						if (stk[stktop].opno == FT) {
+							stktop--;
+						} else {
+							pe(lineno);
+							printf("unmatched \\fP\n");
+						}
+					} else {
+						stk[++stktop].opno = FT;
+						stk[stktop].pl = 1;
+						stk[stktop].parm = n;
+						stk[stktop].lno = lineno;
+					}
+				}
+			}
+	}
+	/*
+	 * We've hit the end and look at all this stuff that hasn't been
+	 * matched yet!  Complain, complain.
+	 */
+	for (i=stktop; i>=0; i--) {
+		complain(i);
+	}
+}
+
+complain(i)
+{
+	pe(stk[i].lno);
+	printf("Unmatched ");
+	prop(i);
+	printf("\n");
+}
+
+prop(i)
+{
+	if (stk[i].pl == 0)
+		printf(".%s", br[stk[i].opno].opbr);
+	else switch(stk[i].opno) {
+	case SZ:
+		printf("\\s%c%d", stk[i].pl, stk[i].parm);
+		break;
+	case FT:
+		printf("\\f%c", stk[i].parm);
+		break;
+	default:
+		printf("Bug: stk[%d].opno = %d = .%s, .%s",
+			i, stk[i].opno, br[stk[i].opno].opbr, br[stk[i].opno].clbr);
+	}
+}
+
+chkcmd(line, mac)
+char *line;
+char *mac;
+{
+	register int i, n;
+
+	/*
+	 * Check to see if it matches top of stack.
+	 */
+	if (stktop >= 0 && eq(mac, br[stk[stktop].opno].clbr))
+		stktop--;	/* OK. Pop & forget */
+	else {
+		/* No. Maybe it's an opener */
+		for (i=0; br[i].opbr; i++) {
+			if (eq(mac, br[i].opbr)) {
+				/* Found. Push it. */
+				stktop++;
+				stk[stktop].opno = i;
+				stk[stktop].pl = 0;
+				stk[stktop].parm = 0;
+				stk[stktop].lno = lineno;
+				break;
+			}
+			/*
+			 * Maybe it's an unmatched closer.
+			 * NOTE: this depends on the fact
+			 * that none of the closers can be
+			 * openers too.
+			 */
+			if (eq(mac, br[i].clbr)) {
+				nomatch(mac);
+				break;
+			}
+		}
+	}
+}
+
+nomatch(mac)
+char *mac;
+{
+	register int i, j;
+
+	/*
+	 * Look for a match further down on stack
+	 * If we find one, it suggests that the stuff in
+	 * between is supposed to match itself.
+	 */
+	for (j=stktop; j>=0; j--)
+		if (eq(mac,br[stk[j].opno].clbr)) {
+			/* Found.  Make a good diagnostic. */
+			if (j == stktop-2) {
+				/*
+				 * Check for special case \fx..\fR and don't
+				 * complain.
+				 */
+				if (stk[j+1].opno==FT && stk[j+1].parm!='R'
+				 && stk[j+2].opno==FT && stk[j+2].parm=='R') {
+					stktop = j -1;
+					return;
+				}
+				/*
+				 * We have two unmatched frobs.  Chances are
+				 * they were intended to match, so we mention
+				 * them together.
+				 */
+				pe(stk[j+1].lno);
+				prop(j+1);
+				printf(" does not match %d: ", stk[j+2].lno);
+				prop(j+2);
+				printf("\n");
+			} else for (i=j+1; i <= stktop; i++) {
+				complain(i);
+			}
+			stktop = j-1;
+			return;
+		}
+	/* Didn't find one.  Throw this away. */
+	pe(lineno);
+	printf("Unmatched .%s\n", mac);
+}
+
+/* eq: are two strings equal? */
+eq(s1, s2)
+char *s1, *s2;
+{
+	return (strcmp(s1, s2) == 0);
+}
+
+/* print the first part of an error message, given the line number */
+pe(lineno)
+int lineno;
+{
+	if (nfiles > 1)
+		printf("%s: ", cfilename);
+	printf("%d: ", lineno);
+}
+
+checkknown(mac)
+char *mac;
+{
+
+	if (eq(mac, "."))
+		return;
+	if (binsrch(mac) >= 0)
+		return;
+	if (mac[0] == '\\' && mac[1] == '"')	/* comments */
+		return;
+
+	pe(lineno);
+	printf("Unknown command: .%s\n", mac);
+}
+
+/*
+ * We have a .de xx line in "line".  Add xx to the list of known commands.
+ */
+addcmd(line)
+char *line;
+{
+	char *mac;
+
+	/* grab the macro being defined */
+	mac = line+4;
+	while (isspace(*mac))
+		mac++;
+	if (*mac == 0) {
+		pe(lineno);
+		printf("illegal define: %s\n", line);
+		return;
+	}
+	mac[2] = 0;
+	if (isspace(mac[1]) || mac[1] == '\\')
+		mac[1] = 0;
+	if (ncmds >= MAXCMDS) {
+		printf("Only %d known commands allowed\n", MAXCMDS);
+		exit(1);
+	}
+	addmac(mac);
+}
+
+/*
+ * Add mac to the list.  We should really have some kind of tree
+ * structure here but this is a quick-and-dirty job and I just don't
+ * have time to mess with it.  (I wonder if this will come back to haunt
+ * me someday?)  Anyway, I claim that .de is fairly rare in user
+ * nroff programs, and the register loop below is pretty fast.
+ */
+addmac(mac)
+char *mac;
+{
+	register char **src, **dest, **loc;
+
+	if (binsrch(mac) >= 0){	/* it's OK to redefine something */
+#ifdef DEBUG
+		printf("binsrch(%s) -> already in table\n", mac);
+#endif DEBUG
+		return;
+	}
+	/* binsrch sets slot as a side effect */
+#ifdef DEBUG
+printf("binsrch(%s) -> %d\n", mac, slot);
+#endif
+	loc = &knowncmds[slot];
+	src = &knowncmds[ncmds-1];
+	dest = src+1;
+	while (dest > loc)
+		*dest-- = *src--;
+	*loc = malloc(3);
+	strcpy(*loc, mac);
+	ncmds++;
+#ifdef DEBUG
+printf("after: %s %s %s %s %s, %d cmds\n", knowncmds[slot-2], knowncmds[slot-1], knowncmds[slot], knowncmds[slot+1], knowncmds[slot+2], ncmds);
+#endif
+}
+
+/*
+ * Do a binary search in knowncmds for mac.
+ * If found, return the index.  If not, return -1.
+ */
+binsrch(mac)
+char *mac;
+{
+	register char *p;	/* pointer to current cmd in list */
+	register int d;		/* difference if any */
+	register int mid;	/* mid point in binary search */
+	register int top, bot;	/* boundaries of bin search, inclusive */
+
+	top = ncmds-1;
+	bot = 0;
+	while (top >= bot) {
+		mid = (top+bot)/2;
+		p = knowncmds[mid];
+		d = p[0] - mac[0];
+		if (d == 0)
+			d = p[1] - mac[1];
+		if (d == 0)
+			return mid;
+		if (d < 0)
+			bot = mid + 1;
+		else
+			top = mid - 1;
+	}
+	slot = bot;	/* place it would have gone */
+	return -1;
+}