Further revisions to the Format update

Drop historical information about the version changes in .changes
files.  It doesn't seem useful at this point.  Specify the format
of Format for source packages separately since referring to the
version format with exceptions and additions is more confusing and
it's not really a version in the same sense.  Add the full list of
supported source package formats in a footnote.  Add a bit more
explanation for how the source package format is used.

diff --git a/policy.sgml b/policy.sgml
index 74f94e8c4665de20ad3cd09454f50943c70791b7..57a26210388f2180c7bbb9559b6e4905800b9322 100644 (file)
--- a/policy.sgml
+++ b/policy.sgml
@@ -2600,14 +2600,20 @@ Package: libc6
        <heading>Debian changes files -- <file>.changes</file></heading>
 
        <p>
-         The .changes files are used by the Debian archive maintenance
-         software to process updates to packages. They contain one
-         paragraph which contains information from the
+         The <file>.changes</file> files are used by the Debian archive
+         maintenance software to process updates to packages. They
+         contain one paragraph which contains information from the
          <tt>debian/control</tt> file and other data about the
          source package gathered via <tt>debian/changelog</tt>
          and <tt>debian/rules</tt>.
        </p>
 
+       <p>
+         <file>.changes</file> files have a format version that is
+         incremented whenever the documented fields or their meaning
+         change.  This document describes format 1.8.
+       </p>
+
        <p>
          The fields in this file are:
 
@@ -2620,10 +2626,10 @@ Package: libc6
            <item><qref id="f-Version"><tt>Version</tt></qref> (mandatory)</item>
            <item><qref id="f-Distribution"><tt>Distribution</tt></qref> (mandatory)</item>
            <item><qref id="f-Urgency"><tt>Urgency</tt></qref> (recommended)</item>
-           <item><qref id="f-Maintainer"><tt>Maintainer</tt></qref> (mandatory) <footnote>The meaning of that field changed in version 1.7.</footnote></item>
-           <item><qref id="f-Changed-By"><tt>Changed-By</tt></qref> <footnote>Introduced in format 1.7.</footnote></item>
+           <item><qref id="f-Maintainer"><tt>Maintainer</tt></qref> (mandatory)</item>
+           <item><qref id="f-Changed-By"><tt>Changed-By</tt></qref></item>
            <item><qref id="f-Description"><tt>Description</tt></qref> (mandatory)</item>
-           <item><qref id="f-Closes"><tt>Closes</tt></qref> <footnote>Introduced in format 1.6.</footnote></item>
+           <item><qref id="f-Closes"><tt>Closes</tt></qref></item>
            <item><qref id="f-Changes"><tt>Changes</tt></qref> (mandatory)</item>
            <item><qref id="f-Checksums"><tt>Checksums-Sha1</tt>
                and <tt>Checksums-Sha256</tt></qref> (recommended)</item>
@@ -3264,25 +3270,30 @@ Package: libc6
          <heading><tt>Format</tt></heading>
 
          <p>
-           In <qref id="debianchangesfiles">changes</qref> files, this field
-           specifies a format revision for the file. The syntax of the
-           format value is the same as that of a package version
-           number except that no epoch or Debian revision is allowed
-           - see <ref id="f-Version">.
+           In <qref id="debianchangesfiles"><file>.changes</file></qref>
+           files, this field declares the format version of that file.
+           The syntax of the field value is the same as that of
+           a <qref id="f-Version">package version number</qref> except
+           that no epoch or Debian revision is allowed.  The format
+           described in this document is <tt>1.8</tt>.
+         </p>
+
+         <p>
+           In <qref id="debiansourcecontrolfiles"> Debian source
+           control</qref> files, this field declares the format of the
+           source package.  The field value is used by programs acting on
+           a source package to interpret the list of files in the source
+           package and determine how to unpack it.  The syntax of the
+           field value is a numeric major revision, a period, a numeric
+           minor revision, and then an optional subtype after whitespace,
+           which if specified is an alphanumeric word in parentheses.
+           The subtype is optional in the syntax but may be mandatory for
+           particular source format revisions.<footnote>
+             The source formats currently supported by the Debian archive
+             software are <tt>1.0</tt>, <tt>3.0 (native)</tt>,
+             and <tt>3.0 (quilt)</tt>.
+           </footnote>
          </p>
-
-         <p>
-           In <qref id="debiansourcecontrolfiles"> Debian source control</qref>
-           files, this field specifies a format revision for the source package.
-           The syntax of the format value is the same as that of a package version
-           number, except that no epoch or Debian revision is allowed
-           and that it can optionally be followed by a parenthesis with a name
-           <footnote>dpkg-source uses the major number and the content of the
-           parenthesis to decide which perl module to use to build or unpack
-           the source package. For instance, Dpkg::Source::Package::V1 for format
-           1.0 and Dpkg::Source::Package::V3::quilt for format 3.0 (quilt)
-           </footnote>.
-         <p>
        </sect1>
 
        <sect1 id="f-Urgency">
@@ -3542,27 +3553,6 @@ Checksums-Sha256:
            must match the list of files in the <tt>Files</tt> field.
          </p>
        </sect1>
-
-       <sect1 id="f-Checksums-Sha1">
-         <heading><tt>Checksums-Sha1</tt></heading>
-
-         <p>
-           This field is similar to the <qref id="f-Files">Files</qref>
-           field, except that it uses the Sha1 algorithm instead of MD5
-           for the checksums.
-         </p>
-       </sect1>
-
-       <sect1 id="f-Checksums-Sha256">
-         <heading><tt>Checksums-Sha256</tt></heading>
-
-         <p>
-           This field is similar to the <qref id="f-Files">Files</qref>
-           field, except that it uses the Sha1 algorithm instead of MD5
-           for the checksums.
-         </p>
-       </sect1>
-
       </sect>
 
       <sect>