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.

1 file changed, 57 insertions, 5 deletions

diff --git a/source/cgit.c b/source/cgit.cindex 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
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