Support -Ios='OpenBSD 5.1' to override uname(3) as the source of the

default value for the mdoc(7) .Os macro.
Needed for man.cgi on the OpenBSD website.

Problem with man.cgi first noticed by deraadt@;
beck@ and deraadt@ agree with the way to solve the issue.

"Please check them in and I'll look into them later!" kristaps@

10 files changed, 60 insertions, 23 deletions

diff --git a/cgi.c b/cgi.c
index b211ac74..4070d425 100644
--- a/cgi.c
+++ b/cgi.c
@@ -733,7 +733,7 @@ format(const struct req *req, const char *file)
 		return;
 	}
 
-	mp = mparse_alloc(MPARSE_AUTO, MANDOCLEVEL_FATAL, NULL, NULL);
+	mp = mparse_alloc(MPARSE_AUTO, MANDOCLEVEL_FATAL, NULL, NULL, NULL);
 	rc = mparse_readfd(mp, fd, file);
 	close(fd);
 
diff --git a/libmandoc.h b/libmandoc.h
index 2a0c28df..7bcf41e1 100644
--- a/libmandoc.h
+++ b/libmandoc.h
@@ -52,7 +52,7 @@ int		 mandoc_strntoi(const char *, size_t, int);
 const char	*mandoc_a2msec(const char*);
 
 void	 	 mdoc_free(struct mdoc *);
-struct	mdoc	*mdoc_alloc(struct roff *, struct mparse *);
+struct	mdoc	*mdoc_alloc(struct roff *, struct mparse *, char *);
 void		 mdoc_reset(struct mdoc *);
 int	 	 mdoc_parseln(struct mdoc *, int, char *, int);
 int		 mdoc_endparse(struct mdoc *);
diff --git a/libmdoc.h b/libmdoc.h
index a23b2366..cf3a20bb 100644
--- a/libmdoc.h
+++ b/libmdoc.h
@@ -24,6 +24,7 @@ enum	mdoc_next {
 
 struct	mdoc {
 	struct mparse	 *parse; /* parse pointer */
+	char		 *defos; /* default argument for .Os */
 	int		  flags; /* parse flags */
 #define	MDOC_HALT	 (1 << 0) /* error in parse: halt */
 #define	MDOC_LITERAL	 (1 << 1) /* in a literal scope */
diff --git a/main.c b/main.c
index 36d02e3a..7c9a5c60 100644
--- a/main.c
+++ b/main.c
@@ -1,7 +1,7 @@
 /*	$Id$ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
- * Copyright (c) 2010, 2011 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2010, 2011, 2012 Ingo Schwarze <schwarze@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -85,6 +85,7 @@ main(int argc, char *argv[])
 	struct curparse	 curp;
 	enum mparset	 type;
 	enum mandoclevel rc;
+	char		*defos;
 
 	progname = strrchr(argv[0], '/');
 	if (progname == NULL)
@@ -97,10 +98,24 @@ main(int argc, char *argv[])
 	type = MPARSE_AUTO;
 	curp.outtype = OUTT_ASCII;
 	curp.wlevel  = MANDOCLEVEL_FATAL;
+	defos = NULL;
 
 	/* LINTED */
-	while (-1 != (c = getopt(argc, argv, "m:O:T:VW:")))
+	while (-1 != (c = getopt(argc, argv, "I:m:O:T:VW:")))
 		switch (c) {
+		case ('I'):
+			if (strncmp(optarg, "os=", 3)) {
+				fprintf(stderr, "-I%s: Bad argument\n",
+						optarg);
+				return((int)MANDOCLEVEL_BADARG);
+			}
+			if (defos) {
+				fprintf(stderr, "-I%s: Duplicate argument\n",
+						optarg);
+				return((int)MANDOCLEVEL_BADARG);
+			}
+			defos = mandoc_strdup(optarg + 3);
+			break;
 		case ('m'):
 			if ( ! moptions(&type, optarg))
 				return((int)MANDOCLEVEL_BADARG);
@@ -125,7 +140,7 @@ main(int argc, char *argv[])
 			/* NOTREACHED */
 		}
 
-	curp.mp = mparse_alloc(type, curp.wlevel, mmsg, &curp);
+	curp.mp = mparse_alloc(type, curp.wlevel, mmsg, &curp, defos);
 
 	/*
 	 * Conditionally start up the lookaside buffer before parsing.
@@ -152,6 +167,7 @@ main(int argc, char *argv[])
 		(*curp.outfree)(curp.outdata);
 	if (curp.mp)
 		mparse_free(curp.mp);
+	free(defos);
 
 	return((int)rc);
 }
diff --git a/mandoc.1 b/mandoc.1
index 778737aa..6bb82c28 100644
--- a/mandoc.1
+++ b/mandoc.1
@@ -1,6 +1,7 @@
 .\"	$Id$
 .\"
 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
+.\" Copyright (c) 2012 Ingo Schwarze <schwarze@openbsd.org>
 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above
@@ -23,6 +24,9 @@
 .Sh SYNOPSIS
 .Nm mandoc
 .Op Fl V
+.Sm off
+.Op Fl I Cm os Li = Ar name
+.Sm on
 .Op Fl m Ns Ar format
 .Op Fl O Ns Ar option
 .Op Fl T Ns Ar output
@@ -49,6 +53,15 @@ output.
 .Pp
 The arguments are as follows:
 .Bl -tag -width Ds
+.Sm off
+.It Fl I Cm os Li = Ar name
+.Sm on
+Override the default operating system
+.Ar name
+for the
+.Xr mdoc 7
+.Sq \&Os
+macro.
 .It Fl m Ns Ar format
 Input format.
 See
diff --git a/mandoc.h b/mandoc.h
index 219972c0..a24db913 100644
--- a/mandoc.h
+++ b/mandoc.h
@@ -413,8 +413,8 @@ int		  mchars_spec2cp(const struct mchars *,
 			const char *, size_t);
 const char	 *mchars_spec2str(const struct mchars *, 
 			const char *, size_t, size_t *);
-struct mparse	 *mparse_alloc(enum mparset, 
-			enum mandoclevel, mandocmsg, void *);
+struct mparse	 *mparse_alloc(enum mparset, enum mandoclevel,
+			mandocmsg, void *, char *);
 void		  mparse_free(struct mparse *);
 void		  mparse_keep(struct mparse *);
 enum mandoclevel  mparse_readfd(struct mparse *, int, const char *);
diff --git a/mandocdb.c b/mandocdb.c
index 603b3ba7..e00f18a4 100644
--- a/mandocdb.c
+++ b/mandocdb.c
@@ -396,7 +396,7 @@ main(int argc, char *argv[])
 	info.lorder = 4321;
 	info.flags = R_DUP;
 
-	mp = mparse_alloc(MPARSE_AUTO, MANDOCLEVEL_FATAL, NULL, NULL);
+	mp = mparse_alloc(MPARSE_AUTO, MANDOCLEVEL_FATAL, NULL, NULL, NULL);
 
 	memset(&buf, 0, sizeof(struct buf));
 	memset(&dbuf, 0, sizeof(struct buf));
diff --git a/mdoc.c b/mdoc.c
index df4b0587..f3cf256e 100644
--- a/mdoc.c
+++ b/mdoc.c
@@ -197,13 +197,14 @@ mdoc_free(struct mdoc *mdoc)
  * Allocate volatile and non-volatile parse resources.  
  */
 struct mdoc *
-mdoc_alloc(struct roff *roff, struct mparse *parse)
+mdoc_alloc(struct roff *roff, struct mparse *parse, char *defos)
 {
 	struct mdoc	*p;
 
 	p = mandoc_calloc(1, sizeof(struct mdoc));
 
 	p->parse = parse;
+	p->defos = defos;
 	p->roff = roff;
 
 	mdoc_hash_init();
diff --git a/mdoc_validate.c b/mdoc_validate.c
index 931bf1a3..261a3030 100644
--- a/mdoc_validate.c
+++ b/mdoc_validate.c
@@ -1,7 +1,7 @@
 /*	$Id$ */
 /*
  * Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
- * Copyright (c) 2010, 2011 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2010, 2011, 2012 Ingo Schwarze <schwarze@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -2192,14 +2192,15 @@ post_os(POST_ARGS)
 	n = mdoc->last;
 
 	/*
-	 * Set the operating system by way of the `Os' macro.  Note that
-	 * if an argument isn't provided and -DOSNAME="\"foo\"" is
-	 * provided during compilation, this value will be used instead
-	 * of filling in "sysname release" from uname().
+	 * Set the operating system by way of the `Os' macro.
+	 * The order of precedence is:
+	 * 1. the argument of the `Os' macro, unless empty
+	 * 2. the -Ios=foo command line argument, if provided
+	 * 3. -DOSNAME="\"foo\"", if provided during compilation
+	 * 4. "sysname release" from uname(3)
  	 */
 
-	if (mdoc->meta.os)
-		free(mdoc->meta.os);
+	free(mdoc->meta.os);
 
 	buf[0] = '\0';
 	if (-1 == (c = concat(buf, n->child, BUFSIZ))) {
@@ -2209,11 +2210,11 @@ post_os(POST_ARGS)
 
 	assert(c);
 
-	/* XXX: yes, these can all be dynamically-adjusted buffers, but
-	 * it's really not worth the extra hackery.
-	 */
-
 	if ('\0' == buf[0]) {
+		if (mdoc->defos) {
+			mdoc->meta.os = mandoc_strdup(mdoc->defos);
+			return(1);
+		}
 #ifdef OSNAME
 		if (strlcat(buf, OSNAME, BUFSIZ) >= BUFSIZ) {
 			mdoc_nmsg(mdoc, n, MANDOCERR_MEM);
diff --git a/read.c b/read.c
index e96621bf..390b2978 100644
--- a/read.c
+++ b/read.c
@@ -66,6 +66,7 @@ struct	mparse {
 	void		 *arg; /* argument to mmsg */
 	const char	 *file; 
 	struct buf	 *secondary;
+	char		 *defos; /* default operating system */
 };
 
 static	void	  resize_buf(struct buf *, size_t);
@@ -247,7 +248,8 @@ pset(const char *buf, int pos, struct mparse *curp)
 	switch (curp->inttype) {
 	case (MPARSE_MDOC):
 		if (NULL == curp->pmdoc) 
-			curp->pmdoc = mdoc_alloc(curp->roff, curp);
+			curp->pmdoc = mdoc_alloc(curp->roff, curp,
+					curp->defos);
 		assert(curp->pmdoc);
 		curp->mdoc = curp->pmdoc;
 		return;
@@ -263,7 +265,8 @@ pset(const char *buf, int pos, struct mparse *curp)
 
 	if (pos >= 3 && 0 == memcmp(buf, ".Dd", 3))  {
 		if (NULL == curp->pmdoc) 
-			curp->pmdoc = mdoc_alloc(curp->roff, curp);
+			curp->pmdoc = mdoc_alloc(curp->roff, curp,
+					curp->defos);
 		assert(curp->pmdoc);
 		curp->mdoc = curp->pmdoc;
 		return;
@@ -720,7 +723,8 @@ mparse_readfd(struct mparse *curp, int fd, const char *file)
 }
 
 struct mparse *
-mparse_alloc(enum mparset inttype, enum mandoclevel wlevel, mandocmsg mmsg, void *arg)
+mparse_alloc(enum mparset inttype, enum mandoclevel wlevel,
+		mandocmsg mmsg, void *arg, char *defos)
 {
 	struct mparse	*curp;
 
@@ -732,6 +736,7 @@ mparse_alloc(enum mparset inttype, enum mandoclevel wlevel, mandocmsg mmsg, void
 	curp->mmsg = mmsg;
 	curp->arg = arg;
 	curp->inttype = inttype;
+	curp->defos = defos;
 
 	curp->roff = roff_alloc(curp);
 	return(curp);