Clarified the role of MDOC_HALT in libmdoc functions by having accessor

functions assert() if they're called after MDOC_HALT is set.

This makes more sense than returning 0 because this return value is used
for parse errors, not programme-flow errors, and it's inconsistent to
use the same value for both.  Plus, prior to this, I'd return 0 without
printing an error message, which would cause failure to go unreported to
the operator.

1 files changed, 8 insertions, 9 deletions

diff --git a/mdoc.c b/mdoc.c
index 389f0bc1..5494b633 100644
--- a/mdoc.c
+++ b/mdoc.c
@@ -106,7 +106,8 @@ const struct mdoc_node *
 mdoc_node(const struct mdoc *m)
 {
 
-	return(MDOC_HALT & m->flags ? NULL : m->first);
+	assert( ! (MDOC_HALT & m->flags));
+	return(m->first);
 }
 
 
@@ -114,7 +115,8 @@ const struct mdoc_meta *
 mdoc_meta(const struct mdoc *m)
 {
 
-	return(MDOC_HALT & m->flags ? NULL : &m->meta);
+	assert( ! (MDOC_HALT & m->flags));
+	return(&m->meta);
 }
 
 
@@ -215,9 +217,8 @@ int
 mdoc_endparse(struct mdoc *m)
 {
 
-	if (MDOC_HALT & m->flags)
-		return(0);
-	else if (mdoc_macroend(m))
+	assert( ! (MDOC_HALT & m->flags));
+	if (mdoc_macroend(m))
 		return(1);
 	m->flags |= MDOC_HALT;
 	return(0);
@@ -227,8 +228,7 @@ int
 mdoc_addspan(struct mdoc *m, const struct tbl_span *sp)
 {
 
-	if (MDOC_HALT & m->flags)
-		return(0);
+	assert( ! (MDOC_HALT & m->flags));
 
 	/* No text before an initial macro. */
 
@@ -250,8 +250,7 @@ int
 mdoc_parseln(struct mdoc *m, int ln, char *buf, int offs)
 {
 
-	if (MDOC_HALT & m->flags)
-		return(0);
+	assert( ! (MDOC_HALT & m->flags));
 
 	m->flags |= MDOC_NEWLINE;