From da7e10015efd2887075c33990c1413265244664d Mon Sep 17 00:00:00 2001
From: op <op@openbsd.org>
Date: Wed, 29 Mar 2023 07:29:17 +0000
Subject: [PATCH] change tagvisit (aka visit-tag-table) to immediately load the
 tag file

before it used to only record the path to the tag file which was loaded
on demand upon find-tag (M-.).  tagvisit did to do a stat + access dance
to know if the path was pointing to a regular, readable file and
loadtags (called lazily by find-tag) trusted those checks...

Instead, just load the tags in tagvisit and drop the lazy mechanics.

ok tb@
---
 usr.bin/mg/mg.1   |  6 +++---
 usr.bin/mg/tags.c | 52 +++++++++++++++++++++--------------------------
 2 files changed, 26 insertions(+), 32 deletions(-)

diff --git a/usr.bin/mg/mg.1 b/usr.bin/mg/mg.1
index f23e3c0472b..beb85f1151f 100644
--- a/usr.bin/mg/mg.1
+++ b/usr.bin/mg/mg.1
@@ -1,7 +1,7 @@
-.\"	$OpenBSD: mg.1,v 1.127 2022/10/20 18:59:24 op Exp $
+.\"	$OpenBSD: mg.1,v 1.128 2023/03/29 07:29:17 op Exp $
 .\" This file is in the public domain.
 .\"
-.Dd $Mdocdate: October 20 2022 $
+.Dd $Mdocdate: March 29 2023 $
 .Dt MG 1
 .Os
 .Sh NAME
@@ -967,7 +967,7 @@ As it moves, convert any characters to upper case.
 Toggle the visible bell.
 If this toggle is on, the modeline will flash.
 .It visit-tags-table
-Record name of the tags file to be used for subsequent find-tag.
+Load tags file to be used for subsequent find-tag.
 .It what-cursor-position
 Display a bunch of useful information about the current location of
 dot.
diff --git a/usr.bin/mg/tags.c b/usr.bin/mg/tags.c
index 41684a863a8..fcb32515c63 100644
--- a/usr.bin/mg/tags.c
+++ b/usr.bin/mg/tags.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tags.c,v 1.24 2023/03/28 21:33:21 tb Exp $	*/
+/*	$OpenBSD: tags.c,v 1.25 2023/03/29 07:29:17 op Exp $	*/
 
 /*
  * This file is in the public domain.
@@ -39,7 +39,6 @@ static void              unloadtags(void);
 #define DEFAULTFN "tags"
 
 char *tagsfn = NULL;
-int  loaded  = FALSE;
 
 /* ctags(1) entries are parsed and maintained in a tree. */
 struct ctag {
@@ -66,15 +65,13 @@ ctagcmp(struct ctag *s, struct ctag *t)
 }
 
 /*
- * Record the filename that contain tags to be used while loading them
- * on first use. If a filename is already recorded, ask user to retain
- * already loaded tags (if any) and unload them if user chooses not to.
+ * Load a tags file.  If a tags file is already loaded, ask the user to
+ * retain loaded tags (i any) and unload them if the user chooses not to.
  */
 int
 tagsvisit(int f, int n)
 {
 	char fname[NFILEN], *bufp, *temp;
-	struct stat sb;
 
 	if (getbufcwd(fname, sizeof(fname)) == FALSE)
 		fname[0] = '\0';
@@ -90,20 +87,6 @@ tagsvisit(int f, int n)
 	if (bufp == NULL)
 		return (ABORT);
 
-	if (stat(bufp, &sb) == -1) {
-		dobeep();
-		ewprintf("stat: %s", strerror(errno));
-		return (FALSE);
-	} else if (S_ISREG(sb.st_mode) == 0) {
-		dobeep();
-		ewprintf("Not a regular file");
-		return (FALSE);
-	} else if (access(bufp, R_OK) == -1) {
-		dobeep();
-		ewprintf("Cannot access file %s", bufp);
-		return (FALSE);
-	}
-
 	if (tagsfn == NULL) {
 		if (bufp[0] == '\0') {
 			if ((tagsfn = strdup(fname)) == NULL) {
@@ -131,8 +114,14 @@ tagsvisit(int f, int n)
 			ewprintf("Starting a new list of tags table");
 			unloadtags();
 		}
-		loaded = FALSE;
 	}
+
+	if (loadtags(tagsfn) == FALSE) {
+		free(tagsfn);
+		tagsfn = NULL;
+		return (FALSE);
+	}
+
 	return (TRUE);
 }
 
@@ -170,14 +159,6 @@ findtag(int f, int n)
 	if (tagsfn == NULL)
 		if ((ret = tagsvisit(f, n)) != TRUE)
 			return (ret);
-	if (!loaded) {
-		if (loadtags(tagsfn) == FALSE) {
-			free(tagsfn);
-			tagsfn = NULL;
-			return (FALSE);
-		}
-		loaded = TRUE;
-	}
 	return pushtag(tok);
 }
 
@@ -300,6 +281,7 @@ poptag(int f, int n)
 int
 loadtags(const char *fn)
 {
+	struct stat sb;
 	char *l;
 	FILE *fd;
 
@@ -308,6 +290,18 @@ loadtags(const char *fn)
 		ewprintf("Unable to open tags file: %s", fn);
 		return (FALSE);
 	}
+	if (fstat(fileno(fd), &sb) == -1) {
+		dobeep();
+		ewprintf("fstat: %s", strerror(errno));
+		fclose(fd);
+		return (FALSE);
+	}
+	if (!S_ISREG(sb.st_mode)) {
+		dobeep();
+		ewprintf("Not a regular file");
+		fclose(fd);
+		return (FALSE);
+	}
 	while ((l = fparseln(fd, NULL, NULL, "\\\\\0",
 	    FPARSELN_UNESCCONT | FPARSELN_UNESCREST)) != NULL) {
 		if (addctag(l) == FALSE) {
-- 
2.20.1