===================================================================
RCS file: /cvs/mandoc/tag.c,v
retrieving revision 1.3
retrieving revision 1.6
diff -u -p -r1.3 -r1.6
--- mandoc/tag.c	2015/07/21 03:26:22	1.3
+++ mandoc/tag.c	2015/07/28 18:38:55	1.6
@@ -1,4 +1,4 @@
-/*      $Id: tag.c,v 1.3 2015/07/21 03:26:22 schwarze Exp $    */
+/*      $Id: tag.c,v 1.6 2015/07/28 18:38:55 schwarze Exp $    */
 /*
  * Copyright (c) 2015 Ingo Schwarze <schwarze@openbsd.org>
  *
@@ -34,6 +34,7 @@
 
 struct tag_entry {
 	size_t	 line;
+	int	 prio;
 	char	 s[];
 };
 
@@ -43,84 +44,97 @@ static	void	 tag_free(void *, void *);
 static	void	*tag_calloc(size_t, size_t, void *);
 
 static struct ohash	 tag_data;
-static char		*tag_fn = NULL;
-static int		 tag_fd = -1;
+static struct tag_files	 tag_files;
 
 
 /*
- * Set up the ohash table to collect output line numbers
- * where various marked-up terms are documented and create
- * the temporary tags file, saving the name for the pager.
+ * Prepare for using a pager.
+ * Not all pagers are capable of using a tag file,
+ * but for simplicity, create it anyway.
  */
-char *
+struct tag_files *
 tag_init(void)
 {
 	struct ohash_info	 tag_info;
+	int			 ofd;
 
-	tag_fn = mandoc_strdup("/tmp/man.XXXXXXXXXX");
+	ofd = -1;
+	tag_files.tfd = -1;
+
+	/* Save the original standard output for use by the pager. */
+
+	if ((tag_files.ofd = dup(STDOUT_FILENO)) == -1)
+		goto fail;
+
+	/* Create both temporary output files. */
+
+	(void)strlcpy(tag_files.ofn, "/tmp/man.XXXXXXXXXX",
+	    sizeof(tag_files.ofn));
+	(void)strlcpy(tag_files.tfn, "/tmp/man.XXXXXXXXXX",
+	    sizeof(tag_files.tfn));
 	signal(SIGHUP, tag_signal);
 	signal(SIGINT, tag_signal);
 	signal(SIGTERM, tag_signal);
-	if ((tag_fd = mkstemp(tag_fn)) == -1) {
-		free(tag_fn);
-		tag_fn = NULL;
-		return(NULL);
-	}
+	if ((ofd = mkstemp(tag_files.ofn)) == -1)
+		goto fail;
+	if ((tag_files.tfd = mkstemp(tag_files.tfn)) == -1)
+		goto fail;
+	if (dup2(ofd, STDOUT_FILENO) == -1)
+		goto fail;
+	close(ofd);
 
+	/*
+	 * Set up the ohash table to collect output line numbers
+	 * where various marked-up terms are documented.
+	 */
+
 	tag_info.alloc = tag_alloc;
 	tag_info.calloc = tag_calloc;
 	tag_info.free = tag_free;
 	tag_info.key_offset = offsetof(struct tag_entry, s);
 	tag_info.data = NULL;
 	ohash_init(&tag_data, 4, &tag_info);
-	return(tag_fn);
-}
+	return(&tag_files);
 
-/*
- * Return the line number where a term is defined,
- * or 0 if the term is unknown.
- */
-size_t
-tag_get(const char *s, size_t len)
-{
-	struct tag_entry	*entry;
-	const char		*end;
-	unsigned int		 slot;
-
-	if (tag_fd == -1)
-		return(0);
-	if (len == 0)
-		len = strlen(s);
-	end = s + len;
-	slot = ohash_qlookupi(&tag_data, s, &end);
-	entry = ohash_find(&tag_data, slot);
-	return(entry == NULL ? 0 : entry->line);
+fail:
+	tag_unlink();
+	if (ofd != -1)
+		close(ofd);
+	if (tag_files.ofd != -1)
+		close(tag_files.ofd);
+	if (tag_files.tfd != -1)
+		close(tag_files.tfd);
+	*tag_files.ofn = '\0';
+	*tag_files.tfn = '\0';
+	tag_files.ofd = -1;
+	tag_files.tfd = -1;
+	return(NULL);
 }
 
 /*
- * Set the line number where a term is defined.
+ * Set the line number where a term is defined,
+ * unless it is already defined at a higher priority.
  */
 void
-tag_put(const char *s, size_t len, size_t line)
+tag_put(const char *s, int prio, size_t line)
 {
 	struct tag_entry	*entry;
-	const char		*end;
+	size_t			 len;
 	unsigned int		 slot;
 
-	if (tag_fd == -1)
+	if (tag_files.tfd <= 0)
 		return;
-	if (len == 0)
-		len = strlen(s);
-	end = s + len;
-	slot = ohash_qlookupi(&tag_data, s, &end);
+	slot = ohash_qlookup(&tag_data, s);
 	entry = ohash_find(&tag_data, slot);
 	if (entry == NULL) {
-		entry = mandoc_malloc(sizeof(*entry) + len + 1);
+		len = strlen(s) + 1;
+		entry = mandoc_malloc(sizeof(*entry) + len);
 		memcpy(entry->s, s, len);
-		entry->s[len] = '\0';
 		ohash_insert(&tag_data, slot, entry);
-	}
+	} else if (entry->prio <= prio)
+		return;
 	entry->line = line;
+	entry->prio = prio;
 }
 
 /*
@@ -134,13 +148,14 @@ tag_write(void)
 	struct tag_entry	*entry;
 	unsigned int		 slot;
 
-	if (tag_fd == -1)
+	if (tag_files.tfd <= 0)
 		return;
-	stream = fdopen(tag_fd, "w");
+	stream = fdopen(tag_files.tfd, "w");
 	entry = ohash_first(&tag_data, &slot);
 	while (entry != NULL) {
 		if (stream != NULL)
-			fprintf(stream, "%s - %zu\n", entry->s, entry->line);
+			fprintf(stream, "%s %s %zu\n",
+			    entry->s, tag_files.ofn, entry->line);
 		free(entry);
 		entry = ohash_next(&tag_data, &slot);
 	}
@@ -153,8 +168,10 @@ void
 tag_unlink(void)
 {
 
-	if (tag_fn != NULL)
-		unlink(tag_fn);
+	if (*tag_files.ofn != '\0')
+		unlink(tag_files.ofn);
+	if (*tag_files.tfn != '\0')
+		unlink(tag_files.tfn);
 }
 
 static void