From: Matúš Olekšák <oleksak.matus@gmail.com>
Date: Wed, 8 Apr 2020 18:48:16 +0000 (+0200)
Subject: zstd: Add support for files created with pzstd
X-Git-Tag: v3.4.3~4^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2c8c561bc40847ef27b7b90502f20c6fa983ae1f;p=thirdparty%2Flibarchive.git

zstd: Add support for files created with pzstd
---

diff --git a/libarchive/archive_read_support_filter_zstd.c b/libarchive/archive_read_support_filter_zstd.c
index c8bb36be7..af7eeb7c1 100644
--- a/libarchive/archive_read_support_filter_zstd.c
+++ b/libarchive/archive_read_support_filter_zstd.c
@@ -119,6 +119,8 @@ zstd_bidder_bid(struct archive_read_filter_bidder *self,
 
 	/* Zstd frame magic values */
 	const unsigned zstd_magic = 0xFD2FB528U;
+	const unsigned zstd_magic_skippable_start = 0x184D2A50U;
+	const unsigned zstd_magic_skippable_mask = 0xFFFFFFF0;
 
 	(void) self; /* UNUSED */
 
@@ -129,6 +131,8 @@ zstd_bidder_bid(struct archive_read_filter_bidder *self,
 	prefix = archive_le32dec(buffer);
 	if (prefix == zstd_magic)
 		return (32);
+	if ((prefix & zstd_magic_skippable_mask) == zstd_magic_skippable_start)
+		return (32);
 
 	return (0);
 }