[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

[PATCH/RFC] deb-version.5: Add an own manpage for Dpkg's version format



I was looking for a way to really close #373003 (dpkg-dev: deb-control.5
old rule for Version hyphenation). In the end it lead me to the
conclusion that Dpkg should contain a full description of its Version
format, which in turn lead to completly copying the section from Policy
since this is probably the best description available. This of course
again leads to a few followup questions:

1) If I would copy this text, who to credit for it? For now I just
copied the copyright notice from Policy but I suspect that might not be
the whole truth given how old it is.
2) Should we really try to include more documentation of dpkg's
behaviour in dpkg itself? (My answer is a clear "yes" to that)
If yes, how do we avoid duplication with policy? After all we probably
can't just delete such stuff from policy since there might be
differences what dpkg supports and what policy allows. But not
documenting dpkg features until they are allowed by Policy is not
a good way either.
3) What do people think of this specific case of copying?
Worth it? Should I try to condense the information more?
What should we do with the text is policy?

Comments welcome.

Gruesse,
	Frank

---
 debian/changelog  |    2 +
 man/ChangeLog     |    9 ++++
 man/deb-control.5 |    7 ++-
 man/deb-version.5 |  124 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 139 insertions(+), 3 deletions(-)
 create mode 100644 man/deb-version.5

diff --git a/debian/changelog b/debian/changelog
index 6c33f1c..9facda3 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -35,6 +35,8 @@ dpkg (1.14.7) UNRELEASED; urgency=low
     Closes: #379418
   * Let dpkg-buildpackage error out early if the version number from
     the changelog is not a valid Debian version. Closes: #216075
+  * Add an own manpage for Dpkg's version format. Mostly stolen
+    from policy. Closes: #373003
 
   [ Updated dpkg translations ]
   * Basque (Piarres Beobide). Closes: #440859
diff --git a/man/ChangeLog b/man/ChangeLog
index fcc2e1a..42bdc37 100644
--- a/man/ChangeLog
+++ b/man/ChangeLog
@@ -1,3 +1,12 @@
+2007-10-06  Frank Lichtenheld  <djpig@debian.org>
+
+	* deb-control.5: Move description of
+	version format to...
+	* deb-version.5: Take the section from
+	policy describing version format and
+	sorting since this is probably as good
+	as it gets for describing these.
+
 2007-09-30  Frank Lichtenheld  <djpig@debian.org>
 
 	* deb-control.5: Remove obsolete sentence regarding
diff --git a/man/deb-control.5 b/man/deb-control.5
index efc40c7..7043ef6 100644
--- a/man/deb-control.5
+++ b/man/deb-control.5
@@ -31,9 +31,9 @@ generate file names by most installation tools.
 .BR Version: " <version string>"
 Typically, this is the original package's version number in whatever form
 the program's author uses. It may also include a Debian revision number
-(for non-native packages). If both version and revision are supplied,
-they are separated by a hyphen, `-'. For this reason, the original version
-may not have a hyphen in its version number.
+(for non-native packages). The exact format and sorting algorithm
+are described in
+.BR deb-version (5).
 .TP
 .BR Maintainer: " <fullname email>"
 Should be in the format `Joe Bloggs <jbloggs@foo.com>', and is typically
@@ -219,6 +219,7 @@ Description: GNU grep, egrep and fgrep.
 .
 .SH SEE ALSO
 .BR deb (5),
+.BR deb-version (5),
 .BR debtags (1),
 .BR dpkg (1),
 .BR dpkg-deb (1).
diff --git a/man/deb-version.5 b/man/deb-version.5
new file mode 100644
index 0000000..ea273ec
--- /dev/null
+++ b/man/deb-version.5
@@ -0,0 +1,124 @@
+.\" Author: ??
+.\" Includes text from the Debian Policy by ??
+.TH deb\-version 5 "2007-10-06" "Debian Project" "Debian"
+.SH NAME
+deb\-version \- Debian package version number format
+.
+.SH SYNOPSIS
+.RI "[ " epoch ":] " upstream_version " [\-" debian_revision " ]"
+.SH DESCRIPTION
+Version numbers as used for Debian binary and source packages
+consist of three components. These are:
+.TP
+.I epoch
+This is a single (generally small) unsigned integer.  It
+may be omitted, in which case zero is assumed.  If it is
+omitted then the \fIupstream_version\fP may not
+contain any colons.
+.IP
+It is provided to allow mistakes in the version numbers
+of older versions of a package, and also a package's
+previous version numbering schemes, to be left behind.
+.TP
+.I upstream_version
+This is the main part of the version number.  It is
+usually the version number of the original ("upstream")
+package from which the \fI.deb\fP file has been made,
+if this is applicable.  Usually this will be in the same
+format as that specified by the upstream author(s);
+however, it may need to be reformatted to fit into the
+package management system's format and comparison
+scheme.
+.IP
+The comparison behavior of the package management system
+with respect to the \fIupstream_version\fP is
+described below.  The \fIupstream_version\fP
+portion of the version number is mandatory.
+.IP
+The \fIupstream_version\fP may contain only
+alphanumerics ("A-Za-z0-9") and the characters
+.BR . " " + " " \- " " : " " ~
+(full stop, plus, hyphen, colon, tilde) and should
+start with a digit.  If there is no
+\fIdebian_revision\fP then hyphens are not allowed;
+if there is no \fIepoch\fP then colons are not
+allowed.
+.TP
+.I debian_revision
+This part of the version number specifies the version of
+the Debian package based on the upstream version.  It
+may contain only alphanumerics and the characters
+.BR + " " . " " ~
+(plus, full stop, tilde) and is
+compared in the same way as the
+\fIupstream_version\fP is.
+.IP
+It is optional; if it isn't present then the
+\fIupstream_version\fP may not contain a hyphen.
+This format represents the case where a piece of
+software was written specifically to be turned into a
+Debian package, and so there is only one "debianisation"
+of it and therefore no revision indication is required.
+.IP
+It is conventional to restart the
+\fIdebian_revision\fP at '1' each time time the
+\fIupstream_version\fP is increased.
+.IP
+Dpkg will break the version
+number apart at the last hyphen in the string (if there
+is one) to determine the \fIupstream_version\fP and
+\fIdebian_revision\fP.  The absence of a
+\fIdebian_revision\fP compares earlier than the
+presence of one (but note that the \fIdebian_revision\fP
+is the least significant part of the version number).
+.SS Sorting Algorithm
+The \fIupstream_version\fP and \fIdebian_revision\fP
+parts are compared by the package management system using the
+same algorithm:
+.PP
+The strings are compared from left to right.
+.PP
+First the initial part of each string consisting entirely of
+non-digit characters is determined.  These two parts (one of
+which may be empty) are compared lexically.  If a difference
+is found it is returned.  The lexical comparison is a
+comparison of ASCII values modified so that all the letters
+sort earlier than all the non-letters and so that a tilde
+sorts before anything, even the end of a part.  For example,
+the following parts are in sorted order: '~~', '~~a', '~',
+the empty part, 'a'.
+.PP
+Then the initial part of the remainder of each string which
+consists entirely of digit characters is determined.  The
+numerical values of these two parts are compared, and any
+difference found is returned as the result of the comparison.
+For these purposes an empty string (which can only occur at
+the end of one or both version strings being compared) counts
+as zero.
+.PP
+These two steps (comparing and removing initial non-digit
+strings and initial digit strings) are repeated until a
+difference is found or both strings are exhausted.
+.PP
+Note that the purpose of epochs is to allow us to leave behind
+mistakes in version numbering, and to cope with situations
+where the version numbering scheme changes.  It is
+\fBnot\fP intended to cope with version numbers containing
+strings of letters which the package management system cannot
+interpret (such as 'ALPHA' or 'pre\-'), or with
+silly orderings.
+.CAVEATS
+The tilde character and its special sorting properties were introduced
+in dpkg, version 1.10 and some parts of dpkg-dev only gained
+support for it later in the 1.10.x series.
+.SH SEE ALSO
+.BR deb-control (5),
+.BR deb (5),
+.BR dpkg (1)
+.SH AUTHORS
+Copyright © 1996,1997,1998 Ian Jackson and Christian Schwarz.
+.sp
+This manual is free software; you may redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 2, or (at your option) any later
+version.
-- 
1.5.3.4

-- 
Frank Lichtenheld <djpig@debian.org>
www: http://www.djpig.de/



Reply to: