This file documents things you should know to write a new debhelper program.
+Any program with a name that debins with dh_ should conform to these
+guidelines (with the historical exception of dh_make).
Standardization:
---------------
Debhelper programs should never output anything to standard output except
error messages, important warnings, and the actual commands they run that
-modify files under debian/ and debian/tmp, etc (this last only if they are
-passed -v, and if you output the commands, you should indent them with 1 tab).
-This is so we don't have a lot of noise output when all the debhelper commands
-in a debian/rules are run, so the important stuff is clearly visible.
+modify files under debian/ (this last only if they are passed -v, and if you
+output the commands, you should indent them with 1 tab). This is so we don't
+have a lot of noise output when all the debhelper commands in a debian/rules
+are run, so the important stuff is clearly visible.
-Debhelper programs should accept the options, -v, -i, -a, -p, --no-act, and
--P, and any long forms of these options, like --verbose . If necessary, the
-options may be ignored.
+Debhelper programs should accept all options listed in the "SHARED
+DEBHELPER OPTIONS" section of debhelper(1), including and any long forms of
+these options, like --verbose . If necessary, the options may be ignored.
If debhelper commands need config files, they should use
debian/package.filename as the name of the config file (replace filename
dh_installdeb is an exception, it will run after the other commands and
merge these modifications into the actual postinst scripts.
+In general, files named debian/*.debhelper are internal to debhelper, and
+their expstence or use should not be relied on by external programs such as
+the build process of a package.
+
Debhelper programs should default to doing exactly what policy says to do.
There are always exceptions. Just ask me.
Introducing Dh_Lib.pm:
---------------------
-Dh_lib.pm is the library used by all debhelper programs to parse their
+Dh_Lib.pm is the library used by all debhelper programs to parse their
arguments and set some useful variables. It's not mandatory that your
-program use Dh_lib.pm, but it will make it a lot easier to keep it in sync
+program use Dh_Lib.pm, but it will make it a lot easier to keep it in sync
with the rest of debhelper if it does, so this is highly encouraged.
(There used to be a version of Dh_lib.pm that was a library of functions for
script, I can dig up that old library for you. Only the perl one is
supported now, though.)
-Use Dh_lib.pm like this:
+Use Dh_Lib.pm like this:
-BEGIN { push @INC, "debian", "/usr/share/debhelper" }
-use Dh_Lib;
+use Debian::Debhelper::Dh_Lib
init();
The BEGIN block is there to make perl look for the module in all the right
places.
-The init() function in the perl version. This causes Dh_lib to
-parse the command line and do some other initialization tasks.
+The init() function causes Dh_lib to parse the command line and do some other
+initialization tasks.
Argument processing:
-------------------
--no-act NO_ACT should the program not actually do anything?
-i,-a,-p,-N DOPACKAGES a space delimited list of the binary packages
to act on (in Dh_Lib.pm, this is an array)
--i,-p,-N DOINDEP a space delimited list of the binary independent
- packages to act on
--a,-p,-N DOARCH a space delimited list of the binary dependent
- packages to act on
+-i DOINDEP set if we're acting on binary independent
+ packages
+-a DOARCH set if we're acting on binary dependent
+ packages
-n NOSCRIPTS if set, do not make any modifications to the
package's postinst, postrm, etc scripts.
-X EXCLUDE exclude a something from processing (you
dh_movefiles will ever use this)
--destdir DESTDIR will be set to a string (probably only
dh_builddeb will ever use this)
+--filename FILENAME will be set to a string
--flavor FLAVOR will be set to a string (probably only
dh_installemacsen will ever use this)
---number NUMBER will be set to a number
+--number PRIORITY will be set to a number (deprecated)
+--priority PRIORITY will be set to a number
Any additional command line parameters that do not start with "-" will be
ignored, and you can access them later just as you normally would.
Dh_Lib.pm also contains a number of functions you may find useful.
-doit()
+doit(@command)
Pass this function an array that is a
shell command. It will run the command (unless $dh{NO_ACT} is set), and
if $dh{VERBOSE} is set, it will also output the command to stdout. You
should use this function for almost all commands your program performs
that manipulate files in the package build directories.
-complex_doit()
+complex_doit($command)
Pass this function a string that is a shell command, it will run it
similarly to how doit() does. You can pass more complicated commands
to this (ie, commands involving piping redirection), however, you
have to worry about things like escaping shell metacharacters.
-verbose_print()
+verbose_print($message)
Pass this command a string, and it will echo it if $dh{VERBOSE} is set.
-error()
+error($errormsg)
Pass this command a string, it will output it to standard error and
exit.
-warning()
+warning($message)
Pass this command a string, and it will output it to standard error
as a warning message.
-tmpdir()
+tmpdir($dir)
Pass this command the name of a binary package, it will return the
name of the tmp directory that will be used as this package's
- package build directory. Typically, this will be "debian/tmp" or
- "debian/package".
-compat()
- Pass this command a number, and if the current compatability level
- equals that number, it will return true. Looks at DH_COMPAT to get
- the compatability level.
-pkgfile()
+ package build directory. Typically, this will be "debian/package".
+compat($num)
+ Pass this command a number, and if the current compatibility level
+ is less than or equal to that number, it will return true.
+ Looks at DH_COMPAT to get the compatibility level.
+pkgfile($package, $basename)
Pass this command the name of a binary package, and the base name of a
file, and it will return the actual filename to use. This is used
for allowing debhelper programs to have configuration files in the
package. The convention is that the files are named
debian/package.filename, and debian/filename is also allowable for
the $dh{MAINPACKAGE}. If the file does not exist, nothing is returned.
-pkgext()
+pkgext($package)
Pass this command the name of a binary package, and it will return
the name to prefix to files in debian/ for this package. For the
$dh{MAINPACKAGE}, it returns nothing (there is no prefix), for the other
packages, it returns "package.".
-isnative()
+isnative($package)
Pass this command the name of a package, it returns 1 if the package
is a native debian package.
As a side effect, $dh{VERSION} is set to the version number of the
package.
-autoscript()
+autoscript($package, $scriptname, $snippetname, $sedcommands)
Pass parameters:
- binary package to be affected
- script to add to
(optional)
This command automatically adds shell script snippets to a debian
maintainer script (like the postinst or prerm).
+dirname($pathname)
+ Return directory part of pathname.
+basename($pathname)
+ Return base of pathname,
+addsubstvar($package, $substvar, $deppackage, $verinfo, $remove)
+ This function adds a dependency on some package to the specified
+ substvar in a package's substvar's file. It needs all these
+ parameters:
+ - binary package that gets the item
+ - name of the substvar to add the item to
+ - the package that will be depended on
+ - version info for the package (optional) (ie: ">= 1.1")
+ - if this last parameter is passed, the thing that would be added
+ is removed instead. This can be useful to ensure that a debhelper
+ command is idempotent. Note that without this parameter, if you
+ call the function twice with the same values it will only add one
+ item to the substvars file.
+delsubstvar($package, $substvar)
+ This function removes the entire line for the substvar from the
+ package's shlibs file.
+excludefile($filename)
+ This function returns true if -X has been used to ask for the file
+ to be excluded.
-- Joey Hess <joeyh@debian.org>
+