nano

commit b37cc32de0a9f6f87a678758105240ed423da22e
parent 6d724f6d072b8f7eceba405e3d8cc42768c7210a
Author: Benno Schulenberg <bensberg@telfort.nl>
Date:   Wed, 14 May 2025 11:04:36 +0200

history: reverse the order in the file-positions list, to latest first

Putting the record for the last-edited file at the top of the list
ensures that (in case of a duplicate entry) the newest entry will
be encountered first and thus reused.  It also makes searching the
list faster, because the files that the user is likely to soon edit
again will be near the top of the list instead of near the end.

This fixes https://savannah.gnu.org/bugs/?67120.

Problem existed since version 2.3.0, since position logging was
introduced, but was aggravated by the recent anchor-saving code.

Diffstat:
M
src/history.c
 | 
41
++++++++++++-----------------------------

1 file changed, 12 insertions(+), 29 deletions(-)
diff --git a/src/history.c b/src/history.c
@@ -410,11 +410,11 @@ void load_poshistory(void)
 	char *phrase = NULL;
 	struct stat fileinfo;
 	size_t dummy = 0;
-	ssize_t count = 0;
+	int count = 0;
 	ssize_t length;
 
 	/* Read and parse each line, and store the extracted data. */
-	while ((length = getline(&phrase, &dummy, histfile)) > 1) {
+	while (count++ < 200 && (length = getline(&phrase, &dummy, histfile)) > 1) {
 		stanza = strchr(phrase, '/');
 		length -= (stanza ? stanza - phrase : 0);
 
@@ -448,17 +448,6 @@ void load_poshistory(void)
 			lastitem->next = newitem;
 
 		lastitem = newitem;
-
-		/* Impose a limit, so the file will not grow indefinitely. */
-		if (++count > 200) {
-			poshiststruct *drop_record = position_history;
-
-			position_history = position_history->next;
-
-			free(drop_record->filename);
-			free(drop_record->anchors);
-			free(drop_record);
-		}
 	}
 
 	if (fclose(histfile) == EOF)
@@ -476,6 +465,7 @@ void save_poshistory(void)
 	FILE *histfile = fopen(poshistname, "wb");
 	struct stat fileinfo;
 	poshiststruct *item;
+	int count = 0;
 
 	if (histfile == NULL) {
 		jot_error(N_("Error writing %s: %s"), poshistname, strerror(errno));
@@ -486,7 +476,7 @@ void save_poshistory(void)
 	if (chmod(poshistname, S_IRUSR | S_IWUSR) < 0)
 		jot_error(N_("Cannot limit permissions on %s: %s"), poshistname, strerror(errno));
 
-	for (item = position_history; item != NULL; item = item->next) {
+	for (item = position_history; item != NULL && count++ < 200; item = item->next) {
 		char *path_and_place;
 		size_t length = (item->anchors == NULL) ? 0 : strlen(item->anchors);
 
@@ -580,31 +570,24 @@ void update_poshistory(void)
 
 	theone = item;
 
-	/* If we didn't find it, make a new node; otherwise, if we're
-	 * not at the end, move the matching one to the end. */
+	/* If no match was found, make a new node; otherwise, unlink the match. */
 	if (theone == NULL) {
 		theone = nmalloc(sizeof(poshiststruct));
 		theone->filename = copy_of(fullpath);
 		theone->anchors = NULL;
-		if (position_history == NULL)
-			position_history = theone;
-		else
-			previous->next = theone;
-	} else if (item->next != NULL) {
-		if (previous == NULL)
-			position_history = item->next;
-		else
-			previous->next = item->next;
-		while (item->next != NULL)
-			item = item->next;
-		item->next = theone;
+	} else if (previous)
+		previous->next = theone->next;
+
+	/* Place the found or new node at the beginning, if not already there. */
+	if (theone != position_history) {
+		theone->next = position_history;
+		position_history = theone;
 	}
 
 	/* Store the last cursor position. */
 	theone->linenumber = openfile->current->lineno;
 	theone->columnnumber = xplustabs() + 1;
 	theone->anchors = free_and_assign(theone->anchors, stringify_anchors());
-	theone->next = NULL;
 
 	free(fullpath);