Unified error and warning message system for all of mandoc,

featuring three message levels, as agreed during the mandoc hackathon:
* FATAL parser failure, cannot produce any output from this input file:
  eventually, we hope to convert most of these to ERRORs.
* ERROR, meaning mandoc cannot cope fully with the input syntax and will
  probably lose information or produce structurally garbled output;
  it will try to produce output anyway but exit non-zero at the end,
  which is eventually intended to make the ports infrastructure happy.
* WARNING, meaning you should clean up the input file, but output
  is probably mostly OK, so this will not cause error-exit at the end.
This commit is mostly just converting the old system to the new one; before
the classification will become really reliable, we must check all messages.

In particular,
* set up a new central message string table in main.c
* drop the old message string tables from man.c and mdoc.c
* get rid of the piece-meal merr enums in libman and libmdoc
* reduce number of error/warning functions from 16 to 6 (still a lot...)

While here, handle a few problems more gracefully:
* allow .Rv and .Ex to work without a prior .Nm
* allow .An to ignore extra arguments
* allow undeclared columns in .Bl -column

Written by kristaps@.

1 files changed, 7 insertions, 3 deletions

diff --git a/usr.bin/mandoc/mdoc_html.c b/usr.bin/mandoc/mdoc_html.c
index 48ee6ae7338..8862f9f22c7 100644
--- a/usr.bin/mandoc/mdoc_html.c
+++ b/usr.bin/mandoc/mdoc_html.c
@@ -1,4 +1,4 @@
-/*	$Id: mdoc_html.c,v 1.16 2010/05/23 20:05:43 schwarze Exp $ */
+/*	$Id: mdoc_html.c,v 1.17 2010/05/23 22:45:00 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009 Kristaps Dzonsons <kristaps@kth.se>
  *
@@ -23,6 +23,7 @@
 #include <string.h>
 #include <unistd.h>
 
+#include "mandoc.h"
 #include "out.h"
 #include "html.h"
 #include "mdoc.h"
@@ -725,6 +726,9 @@ mdoc_nm_pre(MDOC_ARGS)
 {
 	struct htmlpair	tag;
 
+	if (NULL == n->child && NULL == m->name)
+		return(1);
+
 	if (SEC_SYNOPSIS == n->sec && 
 			n->prev && MDOC_LINE & n->flags) {
 		bufcat_style(h, "clear", "both");
@@ -1177,7 +1181,7 @@ mdoc_ex_pre(MDOC_ARGS)
 			h->flags &= ~HTML_NOSPACE;
 	}
 
-	if (n->child->next)
+	if (n->child && n->child->next)
 		print_text(h, "utilities exit");
 	else
 		print_text(h, "utility exits");
@@ -1947,7 +1951,7 @@ mdoc_rv_pre(MDOC_ARGS)
 			print_text(h, "()");
 	}
 
-	if (n->child->next)
+	if (n->child && n->child->next)
 		print_text(h, "functions return");
 	else
 		print_text(h, "function returns");