Fossil

<li> Control Artifacts </li>
<li> Wiki Pages </li>
<li> Ticket Changes </li>
</ul>

<p>These five artifact types are described in the sequel.</p>

<p>In the current implementation (as of 2009-01-25) the artifacts that
make up a fossil repository are stored in in as delta- and zlib-compressed
blobs in an <a href="http://www.sqlite.org/">SQLite</a> database.  This
is an implementation detail and might change in a future release.  For
the purpose of this article "file format" means the format of the artifacts,
not how the artifacts are stored on disk.  It is the artifact format that
is intended to be enduring.  The specifics of how artifacts are stored on
disk, though stable, is not intended to live as long as the
artifact format.</p>

<h2>1.0 The Manifest</h2>

<p>A manifest defines a check-in or version of the project
source tree.  The manifest contains a list of artifacts for
each file in the project and the corresponding filenames, as

<blockquote>
<b>C</b> <i>checkin-comment</i><br>
<b>D</b> <i>time-and-date-stamp</i><br>
<b>F</b> <i>filename</i> <i>SHA1-hash</i> <i>permissions</i> <i>old-name</i><br>
<b>P</b> <i>SHA1-hash</i>+<br>
<b>R</b> <i>repository-checksum</i><br>
<b>T</b> (<b>+</b>|<b>-</b>|<b>*</b>)<i>tag-name  <b>*</b> ?value?</i><br>
<b>U</b> <i>user-login</i><br>
<b>Z</b> <i>manifest-checksum</i>
</blockquote>

<p>
A manifest must have exactly one C-card.  The sole argument to
the C-card is a check-in comment that describes the check-in that

take the pathname of the file relative to the root of the
repository, append a single space (ASCII 0x20), the
size of the file in ASCII decimal, a single newline
character (ASCII 0x0A), and the complete text of the file.
Compute the MD5 checksum of the the result.
</p>

<p>
A manifest might contain one or more T-cards used to set tags or
properties on the check-in.  The format of the T-card is the same as
described in <i>Control Artifacts</i> section below, except that the
second argument is the single characcter "<b>*</b>" instead of an
artifact ID.  The <b>*</b> in place of the artifact ID indicates that
the tag or property applies to the current artifact.  It is not
possible to encode the current artifact ID as part of an artifact,
since the act of inserting the artifact ID would change the artifact ID,
hence a <b>*</b> is used to represent "self".  T-cards are typically
added to manifests in order to set the <b>branch</b> property and a
symbolic name when the check-in is intended to start a new branch.
</p>

<p>
Each manifest has a single U-card.  The argument to the U-card is
the login of the user who created the manifest.  The login name
is encoded using the same character escapes as is used for the
check-in comment argument to the C-card.
</p>