From 178f0fbc6e8522780c6ed73ec5e7edaa63d643a9 Mon Sep 17 00:00:00 2001
From: Bryce Kwon <bryce@brycekwon.com>
Date: Sat, 31 Oct 2026 13:30:00 -0700
Subject: Strip a snapshot name's suffixes once

---
 source/ui-snapshot.c | 52 +++++++++++++++++++++-------------------------------
 1 file changed, 21 insertions(+), 31 deletions(-)

(limited to 'source')

diff --git a/source/ui-snapshot.c b/source/ui-snapshot.c
index 321bf61..04defa6 100644
--- a/source/ui-snapshot.c
+++ b/source/ui-snapshot.c
@@ -211,14 +211,11 @@ static int candidate_resolves(const struct cgit_repo *repo, const char *stem,
  * any is tried as a branch, which a branch spelled like a tag's stem would
  * otherwise win.
  */
-static const char *ref_from_filename(const struct cgit_repo *repo, const char *filename,
-	const struct cgit_snapshot_format *format)
+static char *ref_from_filename(const struct cgit_repo *repo, const char *stem)
 {
 	struct strbuf rev = STRBUF_INIT;
-	char *stem = xstrndup(filename, strlen(filename) - strlen(format->suffix));
 	int found = candidate_resolves(repo, stem, &rev, 1) || candidate_resolves(repo, stem, &rev, 0);
 
-	free(stem);
 	if (!found)
 		strbuf_release(&rev);
 	return found ? strbuf_detach(&rev, NULL) : NULL;
@@ -363,58 +360,51 @@ void cgit_print_snapshot(const char *head, const char *hex, const char *filename
 	const char *sig_filename = NULL;
 	char *archive_name = NULL;
 	char *prefix = NULL;
+	char *ref = NULL;
+	size_t len;
 
 	if (!filename) {
 		cgit_print_error_page(400, "Bad Request", "No snapshot name specified");
 		return;
 	}
 
-	if (ends_with(filename, SIG_SUFFIX)) {
+	if (strip_suffix(filename, SIG_SUFFIX, &len)) {
 		sig_filename = filename;
-		archive_name = xstrdup(filename);
-		archive_name[strlen(archive_name) - strlen(SIG_SUFFIX)] = '\0';
-		filename = archive_name;
+		filename = archive_name = xstrndup(filename, len);
 	}
 
 	f = find_format(filename);
 	if (!f || (!sig_filename && !(ctx.repo->snapshots & cgit_snapshot_format_bit(f)))) {
 		cgit_print_error_page(400, "Bad Request", "Unsupported snapshot format: %s", filename);
-		return;
+		goto done;
 	}
 
-	// The name becomes the prefix of every member of the archive, and a
-	// revision expression such as :/pattern could carry a path in it.
-	if (!hex && dwim && strchr(filename, '/')) {
-		cgit_print_error_page(404, "Not Found", "Not found");
-		return;
-	}
-	// A name that is all suffix names no revision, though the lookup below
-	// would settle on a ref called v.
-	if (!hex && dwim && strlen(filename) == strlen(f->suffix)) {
-		cgit_print_error_page(404, "Not Found", "Not found");
-		return;
-	}
 	if (!hex && dwim) {
-		hex = ref_from_filename(ctx.repo, filename, f);
+		strip_suffix(filename, f->suffix, &len);
+		prefix = xstrndup(filename, len);
+		// The stem becomes the prefix of every member of the archive,
+		// and a revision expression such as :/pattern could carry a path
+		// in it. An empty stem names no revision, though the lookup
+		// would settle on a ref called v.
+		if (len && !strchr(prefix, '/'))
+			hex = ref = ref_from_filename(ctx.repo, prefix);
 		if (!hex) {
 			cgit_print_error_page(404, "Not Found", "Not found");
-			return;
+			goto done;
 		}
-		prefix = xstrdup(filename);
-		prefix[strlen(filename) - strlen(f->suffix)] = '\0';
-	}
-
-	if (!hex)
-		hex = head;
-
-	if (!prefix)
+	} else {
 		prefix = xstrdup(cgit_snapshot_prefix(ctx.repo));
+		if (!hex)
+			hex = head;
+	}
 
 	if (sig_filename)
 		send_sig(f, hex, filename, sig_filename);
 	else
 		send_snapshot(f, hex, prefix, filename);
 
+done:
 	free(prefix);
+	free(ref);
 	free(archive_name);
 }
-- 
cgit 2.11.1