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[78.66.223.148]) by smtp.gmail.com with ESMTPSA id t20sm855663ljk.58.2020.12.20.23.55.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 20 Dec 2020 23:55:24 -0800 (PST) From: =?utf-8?q?Martin_=C3=85gren?= To: Ross Light Cc: git@vger.kernel.org Subject: [PATCH 2/2] pack-format.txt: document lengths at start of delta data Date: Mon, 21 Dec 2020 08:54:59 +0100 Message-Id: X-Mailer: git-send-email 2.30.0.rc1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org We document the delta data as a set of instructions, but forget to document the two lengths that precede those instructions: the length of the base object and the length of the object to be reconstructed. Fix this omission. Reported-by: Ross Light Signed-off-by: Martin Ågren --- Documentation/technical/pack-format.txt | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/Documentation/technical/pack-format.txt b/Documentation/technical/pack-format.txt index 42198de74c..05889a2e43 100644 --- a/Documentation/technical/pack-format.txt +++ b/Documentation/technical/pack-format.txt @@ -82,7 +82,10 @@ Ref-delta can also refer to an object outside the pack (i.e. the so-called "thin pack"). When stored on disk however, the pack should be self contained to avoid cyclic dependency. -The delta data is a sequence of instructions to reconstruct an object +The delta data starts with the length of the base object and the +length of the object to be reconstructed. These lengths are +encoded as varints. The remainder of +the delta data is a sequence of instructions to reconstruct the object from the base object. If the base object is deltified, it must be converted to canonical form first. Each instruction appends more and more data to the target object until it's complete. There are two