From dce9812e5f4b5b2bb520ffc93b9847cb6fcb2075 Mon Sep 17 00:00:00 2001
From: Bryce Kwon <bryce@brycekwon.com>
Date: Sat, 31 Oct 2026 17:48:01 -1000
Subject: Key the cached scan on every setting it uses

Two cgitrc files sharing a cache-root read one list, so strict-export
and trust-scan-config set in one applied to the other, and a changed
setting stayed stale until the list expired. The first request after
an upgrade scans again, and the files under the old names are never
read.
---
 source/cgit.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 57 insertions(+), 5 deletions(-)

(limited to 'source/cgit.c')

diff --git a/source/cgit.c b/source/cgit.c
index f8795d7..3571bc4 100644
--- a/source/cgit.c
+++ b/source/cgit.c
@@ -376,18 +376,70 @@ out:
  */
 static void apply_config(const char *name, const char *value);
 
+/*
+ * The cached list is read back as trusted config, so it is kept under a name
+ * drawn from every setting that changes what the scan writes, from the scan
+ * itself to the defaults cgit_add_repo hands each repository. Two sites
+ * sharing a cache-root, or one that changed a setting, would otherwise read
+ * a list scanned under other settings until it expired.
+ */
+static void build_scan_key(struct strbuf *key, const char *path)
+{
+	const char *texts[] = {
+		path,
+		ctx.cfg.project_list,
+		ctx.cfg.strict_export,
+		ctx.cfg.section,
+		ctx.cfg.module_link,
+		ctx.cfg.clone_url,
+	};
+	const int numbers[] = {
+		ctx.cfg.scan_hidden_path,
+		ctx.cfg.remove_suffix,
+		ctx.cfg.section_from_path,
+		ctx.cfg.enable_git_config,
+		ctx.cfg.trust_scan_config,
+		ctx.cfg.snapshots,
+		ctx.cfg.max_stats,
+		ctx.cfg.branch_sort,
+		ctx.cfg.commit_sort,
+		ctx.cfg.enable_blame,
+		ctx.cfg.enable_commit_graph,
+		ctx.cfg.enable_commit_trailers,
+		ctx.cfg.enable_follow_links,
+		ctx.cfg.enable_gitmodules_links,
+		ctx.cfg.enable_html_serving,
+		ctx.cfg.enable_log_filecount,
+		ctx.cfg.enable_log_linecount,
+		ctx.cfg.enable_mailmap,
+		ctx.cfg.enable_remote_branches,
+		ctx.cfg.enable_subject_links,
+	};
+	size_t i;
+
+	// Each text goes behind its length so no value can run into the next,
+	// and an unset one is told apart from an empty one.
+	for (i = 0; i < ARRAY_SIZE(texts); i++) {
+		if (texts[i])
+			strbuf_addf(key, "%zu|%s", strlen(texts[i]), texts[i]);
+		else
+			strbuf_addch(key, '-');
+	}
+	for (i = 0; i < ARRAY_SIZE(numbers); i++)
+		strbuf_addf(key, "%d|", numbers[i]);
+}
+
 static void process_cached_repolist(const char *path)
 {
 	struct stat st;
+	struct strbuf key = STRBUF_INIT;
 	struct strbuf cached_rc = STRBUF_INIT;
 	time_t age;
-	unsigned long hash;
 	int devnull;
 
-	hash = cache_hash_str(path);
-	if (ctx.cfg.project_list)
-		hash += cache_hash_str(ctx.cfg.project_list);
-	strbuf_addf(&cached_rc, "%s/rc-%8lx", ctx.cfg.cache_root, hash);
+	build_scan_key(&key, path);
+	strbuf_addf(&cached_rc, "%s/rc-%8lx", ctx.cfg.cache_root, cache_hash_str(key.buf));
+	strbuf_release(&key);
 
 	if (stat(cached_rc.buf, &st)) {
 		// Nothing is cached yet, so this request scans in its own
-- 
cgit 2.12.1