When the last file formatted yielded no tags, the tags file got

deleted before starting the pager, even when earlier input files
had written to it; thanks to weerd@ for reporting that bug.

Since we now generate tags for section headers, we almost always
generate at least some.  Consequently, while fixing the above bug,
simplify the code by never deleting the tags file before the pager
exits, not even in the rare case that the file happens to be empty.
Hence, this patch is -75 +63 LOC even though it fixes two bugs.

While deleting the output files belongs after exit from the pager,
closing them should be done before it is started.  Collect the
related code, which was scattered in various places, to where
it belongs, in a dedicated function in the term_tag.c module.
As a side benefit, never fclose(2) stdout, only dup2(2) to it.

Similarly, when the -O tag argument wasn't found in the last file
formatted, there was a complaint about "no such tag" even when the
argument did occur in earlier files.  Fix that by looking for a
matching tag after every formatted file rather than just once at
the very end.  Given that command line arguments aren't properties
of the file(s) being formatted, that check is a job for the main
program, not for the formatters, so while fixing the check, move
it from term_tag.c to main.c.

1 files changed, 2 insertions, 12 deletions

diff --git a/tag.h b/tag.h
index 0d37a66a..407b7c94 100644
--- a/tag.h
+++ b/tag.h
@@ -1,4 +1,4 @@
-/* $Id: tag.h,v 1.11 2020/03/13 15:32:29 schwarze Exp $ */
+/* $Id: tag.h,v 1.12 2020/04/02 22:12:55 schwarze Exp $ */
 /*
  * Copyright (c) 2015, 2018, 2019, 2020 Ingo Schwarze <schwarze@openbsd.org>
  *
@@ -28,17 +28,7 @@
 #define	TAG_FALLBACK	(INT_MAX - 1)	/* Tag only used if unique. */
 #define	TAG_DELETE	(INT_MAX)	/* Tag not used at all. */
 
-/*
- * Return values of tag_check().
- */
-enum tag_result {
-	TAG_OK,		/* Argument exists as a tag. */
-	TAG_MISS,	/* Argument not found. */
-	TAG_EMPTY	/* No tag exists at all. */
-};
-
-
 void		 tag_alloc(void);
+int		 tag_exists(const char *);
 void		 tag_put(const char *, int, struct roff_node *);
-enum tag_result	 tag_check(const char *);
 void		 tag_free(void);