===================================================================
RCS file: /cvs/mandoc/tag.c,v
retrieving revision 1.21
retrieving revision 1.26
diff -u -p -r1.21 -r1.26
--- mandoc/tag.c	2018/11/22 11:30:23	1.21
+++ mandoc/tag.c	2020/01/19 18:02:00	1.26
@@ -1,6 +1,6 @@
-/*	$Id: tag.c,v 1.21 2018/11/22 11:30:23 schwarze Exp $ */
+/*	$Id: tag.c,v 1.26 2020/01/19 18:02:00 schwarze Exp $ */
 /*
- * Copyright (c) 2015, 2016, 2018 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2015,2016,2018,2019,2020 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
@@ -18,9 +18,7 @@
 
 #include <sys/types.h>
 
-#if HAVE_ERR
-#include <err.h>
-#endif
+#include <errno.h>
 #include <limits.h>
 #include <signal.h>
 #include <stddef.h>
@@ -32,6 +30,7 @@
 
 #include "mandoc_aux.h"
 #include "mandoc_ohash.h"
+#include "mandoc.h"
 #include "tag.h"
 
 struct tag_entry {
@@ -54,7 +53,7 @@ static struct tag_files	 tag_files;
  * but for simplicity, create it anyway.
  */
 struct tag_files *
-tag_init(void)
+tag_init(char *tagname)
 {
 	struct sigaction	 sa;
 	int			 ofd;
@@ -62,6 +61,7 @@ tag_init(void)
 	ofd = -1;
 	tag_files.tfd = -1;
 	tag_files.tcpgid = -1;
+	tag_files.tagname = tagname;
 
 	/* Clean up when dying from a signal. */
 
@@ -83,8 +83,10 @@ tag_init(void)
 
 	/* Save the original standard output for use by the pager. */
 
-	if ((tag_files.ofd = dup(STDOUT_FILENO)) == -1)
+	if ((tag_files.ofd = dup(STDOUT_FILENO)) == -1) {
+		mandoc_msg(MANDOCERR_DUP, 0, 0, "%s", strerror(errno));
 		goto fail;
+	}
 
 	/* Create both temporary output files. */
 
@@ -92,12 +94,20 @@ tag_init(void)
 	    sizeof(tag_files.ofn));
 	(void)strlcpy(tag_files.tfn, "/tmp/man.XXXXXXXXXX",
 	    sizeof(tag_files.tfn));
-	if ((ofd = mkstemp(tag_files.ofn)) == -1)
+	if ((ofd = mkstemp(tag_files.ofn)) == -1) {
+		mandoc_msg(MANDOCERR_MKSTEMP, 0, 0,
+		    "%s: %s", tag_files.ofn, strerror(errno));
 		goto fail;
-	if ((tag_files.tfd = mkstemp(tag_files.tfn)) == -1)
+	}
+	if ((tag_files.tfd = mkstemp(tag_files.tfn)) == -1) {
+		mandoc_msg(MANDOCERR_MKSTEMP, 0, 0,
+		    "%s: %s", tag_files.tfn, strerror(errno));
 		goto fail;
-	if (dup2(ofd, STDOUT_FILENO) == -1)
+	}
+	if (dup2(ofd, STDOUT_FILENO) == -1) {
+		mandoc_msg(MANDOCERR_DUP, 0, 0, "%s", strerror(errno));
 		goto fail;
+	}
 	close(ofd);
 
 	/*
@@ -120,6 +130,7 @@ fail:
 	*tag_files.tfn = '\0';
 	tag_files.ofd = -1;
 	tag_files.tfd = -1;
+	tag_files.tagname = NULL;
 	return NULL;
 }
 
@@ -142,11 +153,11 @@ tag_put(const char *s, int prio, size_t line)
 		s += 2;
 
 	/*
-	 * Skip whitespace and whatever follows it,
+	 * Skip whitespace and escapes and whatever follows,
 	 * and if there is any, downgrade the priority.
 	 */
 
-	len = strcspn(s, " \t");
+	len = strcspn(s, " \t\\");
 	if (len == 0)
 		return;
 
@@ -185,12 +196,13 @@ tag_put(const char *s, int prio, size_t line)
 
 		/* A better entry is already present, ignore the new one. */
 
-		if (entry->prio > 0 && entry->prio < prio)
+		if (entry->prio != -1 && entry->prio < prio)
 			return;
 
 		/* The existing entry is worse, clear it. */
 
-		if (entry->prio < 1 || entry->prio > prio)
+		if (entry->prio == -1 || entry->prio == 0 ||
+		    entry->prio > prio)
 			entry->nlines = 0;
 	}
 
@@ -216,21 +228,27 @@ tag_write(void)
 	struct tag_entry	*entry;
 	size_t			 i;
 	unsigned int		 slot;
+	int			 empty;
 
 	if (tag_files.tfd <= 0)
 		return;
 	if (tag_files.tagname != NULL && ohash_find(&tag_data,
             ohash_qlookup(&tag_data, tag_files.tagname)) == NULL) {
-		warnx("%s: no such tag", tag_files.tagname);
+		mandoc_msg(MANDOCERR_TAG, 0, 0, "%s", tag_files.tagname);
 		tag_files.tagname = NULL;
 	}
-	stream = fdopen(tag_files.tfd, "w");
+	if ((stream = fdopen(tag_files.tfd, "w")) == NULL)
+		mandoc_msg(MANDOCERR_FDOPEN, 0, 0, "%s", strerror(errno));
+	empty = 1;
 	entry = ohash_first(&tag_data, &slot);
 	while (entry != NULL) {
-		if (stream != NULL && entry->prio >= 0)
-			for (i = 0; i < entry->nlines; i++)
+		if (stream != NULL && entry->prio != -1) {
+			for (i = 0; i < entry->nlines; i++) {
 				fprintf(stream, "%s %s %zu\n",
 				    entry->s, tag_files.ofn, entry->lines[i]);
+				empty = 0;
+			}
+		}
 		free(entry->lines);
 		free(entry);
 		entry = ohash_next(&tag_data, &slot);
@@ -241,6 +259,10 @@ tag_write(void)
 	else
 		close(tag_files.tfd);
 	tag_files.tfd = -1;
+	if (empty) {
+		unlink(tag_files.tfn);
+		*tag_files.tfn = '\0';
+	}
 }
 
 void