[PATCH v3 03/10] builtin/index-pack.c: allow stripping arbitrary extensions

From: Taylor Blau <me@ttaylorr.com>
To: git@vger.kernel.org
Cc: dstolee@microsoft.com, gitster@pobox.com, jrnieder@gmail.com,
	peff@peff.net
Subject: [PATCH v3 03/10] builtin/index-pack.c: allow stripping arbitrary extensions
Date: Mon, 25 Jan 2021 18:37:22 -0500	[thread overview]
Message-ID: <8a3e70454b9bc64fc7a5ff07d47f7fde018e6a3d.1611617820.git.me@ttaylorr.com> (raw)
In-Reply-To: <cover.1611617819.git.me@ttaylorr.com>

To derive the filename for a .idx file, 'git index-pack' uses
derive_filename() to strip the '.pack' suffix and add the new suffix.

Prepare for stripping off suffixes other than '.pack' by making the
suffix to strip a parameter of derive_filename(). In order to make this
consistent with the "suffix" parameter which does not begin with a ".",
an additional check in derive_filename.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
---
 builtin/index-pack.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index 557bd2f348..c758f3b8e9 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -1436,15 +1436,15 @@ static void fix_unresolved_deltas(struct hashfile *f)
 	free(sorted_by_pos);
 }
 
-static const char *derive_filename(const char *pack_name, const char *suffix,
-				   struct strbuf *buf)
+static const char *derive_filename(const char *pack_name, const char *strip,
+				   const char *suffix, struct strbuf *buf)
 {
 	size_t len;
-	if (!strip_suffix(pack_name, ".pack", &len))
-		die(_("packfile name '%s' does not end with '.pack'"),
-		    pack_name);
+	if (!strip_suffix(pack_name, strip, &len) || !len ||
+	    pack_name[len - 1] != '.')
+		die(_("packfile name '%s' does not end with '.%s'"),
+		    pack_name, strip);
 	strbuf_add(buf, pack_name, len);
-	strbuf_addch(buf, '.');
 	strbuf_addstr(buf, suffix);
 	return buf->buf;
 }
@@ -1459,7 +1459,7 @@ static void write_special_file(const char *suffix, const char *msg,
 	int msg_len = strlen(msg);
 
 	if (pack_name)
-		filename = derive_filename(pack_name, suffix, &name_buf);
+		filename = derive_filename(pack_name, "pack", suffix, &name_buf);
 	else
 		filename = odb_pack_name(&name_buf, hash, suffix);
 
@@ -1824,7 +1824,7 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 	if (from_stdin && hash_algo)
 		die(_("--object-format cannot be used with --stdin"));
 	if (!index_name && pack_name)
-		index_name = derive_filename(pack_name, "idx", &index_name_buf);
+		index_name = derive_filename(pack_name, "pack", "idx", &index_name_buf);
 
 	if (verify) {
 		if (!index_name)
-- 
2.30.0.138.g6d7191ea01

