diff options
Diffstat (limited to 'doc/PROGRAMMING')
| -rw-r--r-- | doc/PROGRAMMING | 110 |
1 files changed, 72 insertions, 38 deletions
diff --git a/doc/PROGRAMMING b/doc/PROGRAMMING index 891d31b0..6cae08a5 100644 --- a/doc/PROGRAMMING +++ b/doc/PROGRAMMING @@ -1,4 +1,6 @@ This file documents things you should know to write a new debhelper program. +Any program with a name that begins with dh_ should conform to these +guidelines (with the historical exception of dh_make). Standardization: --------------- @@ -11,14 +13,14 @@ pollute the name space too much. 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(7), including 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 @@ -29,19 +31,25 @@ information that appears in the config files, on their command lines, if possible, and apply that information to the first package they act on. Debhelper programs should never modify the debian/postinst, debian/prerm, -etc scripts, instead, they can add lines to debian/postinst.debhelper, etc. +etc scripts. Instead, they can add lines to debian/postinst.debhelper, etc. The autoscript() function (see below) is one easy way to do this. 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 existence 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 @@ -49,17 +57,16 @@ shell scripts. If you want to write a debhelper command that is a shell 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: ------------------- @@ -78,10 +85,10 @@ switch variable description --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 @@ -104,6 +111,8 @@ switch variable description other program. (This is an array) -m M_PARAMS will be set to a string, you decide what it means to your program +-l L_PARAMS will be set to a string, you decide what it + means to your program -V V_FLAG will be set to a string, you decide what it means to your program -V V_FLAG_SET will be 1 if -V was specified, even if no @@ -120,9 +129,11 @@ switch variable description 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. @@ -137,7 +148,7 @@ The following keys are also set in the %dh hash when you call init(): MAINPACKAGE the name of the first binary package listed in debian/control FIRSTPACKAGE the first package we were instructed to act on. This package - typically gets special treatment, additional arguments + typically gets special treatment; additional arguments specified on the command line may effect it. Functions: @@ -145,35 +156,34 @@ Functions: 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 @@ -181,17 +191,17 @@ pkgfile() 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, $sedcommands) Pass parameters: - binary package to be affected - script to add to @@ -200,5 +210,29 @@ autoscript() (optional) This command automatically adds shell script snippets to a debian maintainer script (like the postinst or prerm). +dirname($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> --- Joey Hess <joeyh@master.debian.org> |