[ViewVC] Annotation of: cvs/cvsroot/App-Staticperl/README

NAME
    staticperl - perl, libc, 100 modules, all in one 500kb file

SYNOPSIS
       staticperl help      # print the embedded documentation
       staticperl fetch     # fetch and unpack perl sources
       staticperl configure # fetch and then configure perl
       staticperl build     # configure and then build perl
       staticperl install   # build and then install perl
       staticperl clean     # clean most intermediate files (restart at configure)
       staticperl distclean # delete everything installed by this script
       staticperl cpan      # invoke CPAN shell
       staticperl instmod path...        # install unpacked modules
       staticperl instcpan modulename... # install modules from CPAN
       staticperl mkbundle <bundle-args...> # see documentation
       staticperl mkperl <bundle-args...>   # see documentation

    Typical Examples:

       staticperl install   # fetch, configure, build and install perl
       staticperl cpan      # run interactive cpan shell
       staticperl mkperl -M '"Config_heavy.pl"' # build a perl that supports -V
       staticperl mkperl -MAnyEvent::Impl::Perl -MAnyEvent::HTTPD -MURI -MURI::http
                            # build a perl with the above modules linked in

DESCRIPTION
    This script helps you creating single-file perl interpreters, or
    embedding a perl interpreter in your applications. Single-file means
    that it is fully self-contained - no separate shared objects, no
    autoload fragments, no .pm or .pl files are needed. And when linking
    statically, you can create (or embed) a single file that contains perl
    interpreter, libc, all the modules you need and all the libraries you
    need.

    With uClibc and upx on x86, you can create a single 500kb binary that
    contains perl and 100 modules such as POSIX, AnyEvent, EV, IO::AIO, Coro
    and so on. Or any other choice of modules.

    The created files do not need write access to the file system (like PAR
    does). In fact, since this script is in many ways similar to
    PAR::Packer, here are the differences:

    *   The generated executables are much smaller than PAR created ones.

        Shared objects and the perl binary contain a lot of extra info,
        while the static nature of staticperl allows the linker to remove
        all functionality and meta-info not required by the final
        executable. Even extensions statically compiled into perl at build
        time will only be present in the final executable when needed.

        In addition, staticperl can strip perl sources much more effectively
        than PAR.

    *   The generated executables start much faster.

        There is no need to unpack files, or even to parse Zip archives
        (which is slow and memory-consuming business).

    *   The generated executables don't need a writable filesystem.

        staticperl loads all required files directly from memory. There is
        no need to unpack files into a temporary directory.

    *   More control over included files.

        PAR tries to be maintenance and hassle-free - it tries to include
        more files than necessary to make sure everything works out of the
        box. The extra files (such as the unicode database) can take
        substantial amounts of memory and file size.

        With staticperl, the burden is mostly with the developer - only
        direct compile-time dependencies and AutoLoader are handled
        automatically. This means the modules to include often need to be
        tweaked manually.

    *   PAR works out of the box, staticperl does not.

        Maintaining your own custom perl build can be a pain in the ass, and
        while staticperl tries to make this easy, it still requires a custom
        perl build and possibly fiddling with some modules. PAR is likely to
        produce results faster.

HOW DOES IT WORK?
    Simple: staticperl downloads, compile and installs a perl version of
    your choice in ~/.staticperl. You can add extra modules either by
    letting staticperl install them for you automatically, or by using CPAN
    and doing it interactively. This usually takes 5-10 minutes, depending
    on the speed of your computer and your internet connection.

    It is possible to do program development at this stage, too.

    Afterwards, you create a list of files and modules you want to include,
    and then either build a new perl binary (that acts just like a normal
    perl except everything is compiled in), or you create bundle files
    (basically C sources you can use to embed all files into your project).

    This step is very fast (a few seconds if PPI is not used for stripping,
    more seconds otherwise, as PPI is very slow), and can be tweaked and
    repeated as often as necessary.

THE STATICPERL SCRIPT
    This module installs a script called staticperl into your perl binary
    directory. The script is fully self-contained, and can be used without
    perl (for example, in an uClibc chroot environment). In fact, it can be
    extracted from the "App::Staticperl" distribution tarball as
    bin/staticperl, without any installation.

    staticperl interprets the first argument as a command to execute,
    optionally followed by any parameters.

    There are two command categories: the "phase 1" commands which deal with
    installing perl and perl modules, and the "phase 2" commands, which deal
    with creating binaries and bundle files.

  PHASE 1 COMMANDS: INSTALLING PERL
    The most important command is install, which does basically everything.
    The default is to download and install perl 5.12.2 and a few modules
    required by staticperl itself, but all this can (and should) be changed
    - see CONFIGURATION, below.

    The command

       staticperl install

    Is normally all you need: It installs the perl interpreter in
    ~/.staticperl/perl. It downloads, configures, builds and installs the
    perl interpreter if required.

    Most of the following commands simply run one or more steps of this
    sequence.

    To force recompilation or reinstallation, you need to run staticperl
    distclean first.

    staticperl fetch
        Runs only the download and unpack phase, unless this has already
        happened.

    staticperl configure
        Configures the unpacked perl sources, potentially after downloading
        them first.

    staticperl build
        Builds the configured perl sources, potentially after automatically
        configuring them.

    staticperl install
        Wipes the perl installation directory (usually ~/.staticperl/perl)
        and installs the perl distribution, potentially after building it
        first.

    staticperl cpan [args...]
        Starts an interactive CPAN shell that you can use to install further
        modules. Installs the perl first if necessary, but apart from that,
        no magic is involved: you could just as well run it manually via
        ~/.staticperl/perl/bin/cpan.

        Any additional arguments are simply passed to the cpan command.

    staticperl instcpan module...
        Tries to install all the modules given and their dependencies, using
        CPAN.

        Example:

           staticperl instcpan EV AnyEvent::HTTPD Coro

    staticperl instsrc directory...
        In the unlikely case that you have unpacked perl modules around and
        want to install from these instead of from CPAN, you can do this
        using this command by specifying all the directories with modules in
        them that you want to have built.

    staticperl clean
        Runs make distclean in the perl source directory (and potentially
        cleans up other intermediate files). This can be used to clean up
        intermediate files without removing the installed perl interpreter.

    staticperl distclean
        This wipes your complete ~/.staticperl directory. Be careful with
        this, it nukes your perl download, perl sources, perl distribution
        and any installed modules. It is useful if you wish to start over
        "from scratch" or when you want to uninstall staticperl.

  PHASE 2 COMMANDS: BUILDING PERL BUNDLES
    Building (linking) a new perl binary is handled by a separate script. To
    make it easy to use staticperl from a chroot, the script is embedded
    into staticperl, which will write it out and call for you with any
    arguments you pass:

       staticperl mkbundle mkbundle-args...

    In the oh so unlikely case of something not working here, you can run
    the script manually as well (by default it is written to
    ~/.staticperl/mkbundle).

    mkbundle is a more conventional command and expect the argument syntax
    commonly used on UNIX clones. For example, this command builds a new
    perl binary and includes Config.pm (for perl -V), AnyEvent::HTTPD, URI
    and a custom httpd script (from eg/httpd in this distribution):

       # first make sure we have perl and the required modules
       staticperl instcpan AnyEvent::HTTPD

       # now build the perl
       staticperl mkperl -M'"Config_heavy.pl"' -MAnyEvent::Impl::Perl \
                         -MAnyEvent::HTTPD -MURI::http \
                         --add 'eg/httpd httpd.pm'

       # finally, invoke it
       ./perl -Mhttpd

    As you can see, things are not quite as trivial: the Config module has a
    hidden dependency which is not even a perl module (Config_heavy.pl),
    AnyEvent needs at least one event loop backend that we have to specify
    manually (here AnyEvent::Impl::Perl), and the URI module (required by
    AnyEvent::HTTPD) implements various URI schemes as extra modules - since
    AnyEvent::HTTPD only needs "http" URIs, we only need to include that
    module. I found out about these dependencies by carefully watching any
    error messages about missing modules...

   OPTION PROCESSING
    All options can be given as arguments on the command line (typically
    using long (e.g. "--verbose") or short option (e.g. "-v") style). Since
    specifying a lot of modules can make the command line very cumbersome,
    you can put all long options into a "bundle specification file" (with or
    without "--" prefix) and specify this bundle file instead.

    For example, the command given earlier could also look like this:

       staticperl mkperl httpd.bundle

    And all options could be in httpd.bundle:

       use "Config_heavy.pl"
       use AnyEvent::Impl::Perl
       use AnyEvent::HTTPD
       use URI::http
       add eg/httpd httpd.pm

    All options that specify modules or files to be added are processed in
    the order given on the command line (that affects the "--use" and
    "--eval" options at the moment).

   MKBUNDLE OPTIONS
    --verbose | -v
        Increases the verbosity level by one (the default is 1).

    --quiet | -q
        Decreases the verbosity level by one.

    --strip none|pod|ppi
        Specify the stripping method applied to reduce the file of the perl
        sources included.

        The default is "pod", which uses the Pod::Strip module to remove all
        pod documentation, which is very fast and reduces file size a lot.

        The "ppi" method uses PPI to parse and condense the perl sources.
        This saves a lot more than just Pod::Strip, and is generally safer,
        but is also a lot slower, so is best used for production builds.
        Note that this method doesn't optimise for raw file size, but for
        best compression (that means that the uncompressed file size is a
        bit larger, but the files compress better, e.g. with upx).

        Last not least, if you need accurate line numbers in error messages,
        or in the unlikely case where "pod" is too slow, or some module gets
        mistreated, you can specify "none" to not mangle included perl
        sources in any way.

    --perl
        After writing out the bundle files, try to link a new perl
        interpreter. It will be called perl and will be left in the current
        working directory. The bundle files will be removed.

        This switch is automatically used when staticperl is invoked with
        the "mkperl" command (instead of "mkbundle"):

           # build a new ./perl with only common::sense in it - very small :)
           staticperl mkperl -Mcommon::sense

    --use module | -Mmodule
        Include the named module and all direct dependencies. This is done
        by "require"'ing the module in a subprocess and tracing which other
        modules and files it actually loads. If the module uses AutoLoader,
        then all splitfiles will be included as well.

        Example: include AnyEvent and AnyEvent::Impl::Perl.

           staticperl mkbundle --use AnyEvent --use AnyEvent::Impl::Perl

        Sometimes you want to load old-style "perl libraries" (.pl files),
        or maybe other weirdly named files. To do that, you need to quote
        the name in single or double quotes. When given on the command line,
        you probably need to quote once more to avoid your shell
        interpreting it. Common cases that need this are Config_heavy.pl and
        utf8_heavy.pl.

        Example: include the required files for perl -V to work in all its
        glory (Config.pm is included automatically by this).

           # bourne shell
           staticperl mkbundle --use '"Config_heavy.pl"'

           # bundle specification file
           use "Config_heavy.pl"

        The "-Mmodule" syntax is included as an alias that might be easier
        to remember than "use". Or maybe it confuses people. Time will tell.
        Or maybe not. Argh.

    --eval "perl code" | -e "perl code"
        Sometimes it is easier (or necessary) to specify dependencies using
        perl code, or maybe one of the modules you use need a special use
        statement. In that case, you can use "eval" to execute some perl
        snippet or set some variables or whatever you need. All files
        "require"'d or "use"'d in the script are included in the final
        bundle.

        Keep in mind that mkbundle will only "require" the modules named by
        the "--use" option, so do not expect the symbols from modules you
        "--use"'d earlier on the command line to be available.

        Example: force AnyEvent to detect a backend and therefore include it
        in the final bundle.

           staticperl mkbundle --eval 'use AnyEvent; AnyEvent::detect'

           # or like this
           staticperl mkbundle -MAnyEvent --eval 'use AnyEvent; AnyEvent::detect'

        Example: use a separate "bootstrap" script that "use"'s lots of
        modules and include this in the final bundle, to be executed
        automatically.

           staticperl mkbundle --eval 'do "bootstrap"' --boot bootstrap

    --boot filename
        Include the given file in the bundle and arrange for it to be
        executed (using a "require") before anything else when the new perl
        is initialised. This can be used to modify @INC or anything else
        before the perl interpreter executes scripts given on the command
        line (or via "-e"). This works even in an embedded interpreter.

    --add "file" | --add "file alias"
        Adds the given (perl) file into the bundle (and optionally call it
        "alias"). This is useful to include any custom files into the
        bundle.

        Example: embed the file httpd as httpd.pm when creating the bundle.

           staticperl mkperl --add "httpd httpd.pm"

        It is also a great way to add any custom modules:

           # specification file
           add file1 myfiles/file1
           add file2 myfiles/file2
           add file3 myfiles/file3

    --binadd "file" | --add "file alias"
        Just like "--add", except that it treats the file as binary and adds
        it without any processing.

        You should probably add a "/" prefix to avoid clashing with embedded
        perl files (whose paths do not start with "/"), and/or use a special
        directory, such as "/res/name".

        You can later get a copy of these files by calling "staticperl::find
        "alias"".

    --static
        When "--perl" is also given, link statically instead of dynamically.
        The default is to link the new perl interpreter fully dynamic (that
        means all perl modules are linked statically, but all external
        libraries are still referenced dynamically).

        Keep in mind that Solaris doesn't support static linking at all, and
        systems based on GNU libc don't really support it in a usable
        fashion either. Try uClibc if you want to create fully statically
        linked executables, or try the "--staticlibs" option to link only
        some libraries statically.

    any other argument
        Any other argument is interpreted as a bundle specification file,
        which supports most long options (without extra quoting), one option
        per line.

  STATCPERL CONFIGURATION AND HOOKS
    During (each) startup, staticperl tries to source the following shell
    files in order:

       /etc/staticperlrc
       ~/.staticperlrc
       $STATICPERL/rc

    They can be used to override shell variables, or define functions to be
    called at specific phases.

    Note that the last file is erased during staticperl distclean, so
    generally should not be used.

   CONFIGURATION VARIABLES
   Variables you *should* override
    "EMAIL"
        The e-mail address of the person who built this binary. Has no good
        default, so should be specified by you.

    "CPAN"
        The URL of the CPAN mirror to use (e.g.
        <http://mirror.netcologne.de/cpan/>).

    "EXTRA_MODULES"
        Additional modules installed during staticperl install. Here you can
        set which modules you want have to installed from CPAN.

        Example: I really really need EV, AnyEvent, Coro and AnyEvent::AIO.

           EXTRA_MODULES="EV AnyEvent Coro AnyEvent::AIO"

        Note that you can also use a "postinstall" hook to achieve this, and
        more.

   Variables you might *want* to override
    "STATICPERL"
        The directory where staticperl stores all its files (default:
        ~/.staticperl).

    "PERL_MM_USE_DEFAULT", "EV_EXTRA_DEFS", ...
        Usually set to 1 to make modules "less inquisitive" during their
        installation, you can set any environment variable you want - some
        modules (such as Coro or EV) use environment variables for further
        tweaking.

    "PERL_VERSION"
        The perl version to install - default is currently 5.12.2, but 5.8.9
        is also a good choice (5.8.9 is much smaller than 5.12.2, while
        5.10.1 is about as big as 5.12.2).

    "PERL_PREFIX"
        The prefix where perl gets installed (default: $STATICPERL/perl),
        i.e. where the bin and lib subdirectories will end up.

    "PERL_CONFIGURE"
        Additional Configure options - these are simply passed to the perl
        Configure script. For example, if you wanted to enable dynamic
        loading, you could pass "-Dusedl". To enable ithreads (Why would you
        want that insanity? Don't! Use forks instead!) you would pass
        "-Duseithreads" and so on.

        More commonly, you would either activate 64 bit integer support
        ("-Duse64bitint"), or disable large files support (-Uuselargefiles),
        to reduce filesize further.

    "PERL_CPPFLAGS", "PERL_OPTIMIZE", "PERL_LDFLAGS", "PERL_LIBS"
        These flags are passed to perl's Configure script, and are generally
        optimised for small size (at the cost of performance). Since they
        also contain subtle workarounds around various build issues,
        changing these usually requires understanding their default values -
        best look at the top of the staticperl script for more info on
        these.

   Variables you probably *do not want* to override
    "MKBUNDLE"
        Where staticperl writes the "mkbundle" command to (default:
        $STATICPERL/mkbundle).

    "STATICPERL_MODULES"
        Additional modules needed by "mkbundle" - should therefore not be
        changed unless you know what you are doing.

   OVERRIDABLE HOOKS
    In addition to environment variables, it is possible to provide some
    shell functions that are called at specific times. To provide your own
    commands, just define the corresponding function.

    Example: install extra modules from CPAN and from some directories at
    staticperl install time.

       postinstall() {
          rm -rf lib/threads* # weg mit Schaden
          instcpan IO::AIO EV
          instsrc ~/src/AnyEvent
          instsrc ~/src/XML-Sablotron-1.0100001
          instcpan Anyevent::AIO AnyEvent::HTTPD
       }

    postconfigure
        Called after configuring, but before building perl. Current working
        directory is the perl source directory.

        Could be used to tailor/patch config.sh (followed by ./Configure -S)
        or do any other modifications.

    postbuild
        Called after building, but before installing perl. Current working
        directory is the perl source directory.

        I have no clue what this could be used for - tell me.

    postinstall
        Called after perl and any extra modules have been installed in
        $PREFIX, but before setting the "installation O.K." flag.

        The current working directory is $PREFIX, but maybe you should not
        rely on that.

        This hook is most useful to customise the installation, by deleting
        files, or installing extra modules using the "instcpan" or "instsrc"
        functions.

        The script must return with a zero exit status, or the installation
        will fail.

ANATOMY OF A BUNDLE
    When not building a new perl binary, "mkbundle" will leave a number of
    files in the current working directory, which can be used to embed a
    perl interpreter in your program.

    Intimate knowledge of perlembed and preferably some experience with
    embedding perl is highly recommended.

    "mkperl" (or the "--perl" option) basically does this to link the new
    interpreter (it also adds a main program to bundle.):

       $Config{cc} $(cat bundle.ccopts) -o perl bundle.c $(cat bundle.ldopts)

    bundle.h
        A header file that contains the prototypes of the few symbols
        "exported" by bundle.c, and also exposes the perl headers to the
        application.

        staticperl_init ()
            Initialises the perl interpreter. You can use the normal perl
            functions after calling this function, for example, to define
            extra functions or to load a .pm file that contains some
            initialisation code, or the main program function:

               XS (xsfunction)
               {
                 dXSARGS;

                 // now we have items, ST(i) etc.
               }

               static void
               run_myapp(void)
               {
                  staticperl_init ();
                  newXSproto ("myapp::xsfunction", xsfunction, __FILE__, "$$;$");
                  eval_pv ("require myapp::main", 1); // executes "myapp/main.pm"
               }

        staticperl_xs_init (pTHX)
            Sometimes you need direct control over "perl_parse" and
            "perl_run", in which case you do not want to use
            "staticperl_init" but call them on your own.

            Then you need this function - either pass it directly as the
            "xs_init" function to "perl_parse", or call it from your own
            "xs_init" function.

        staticperl_cleanup ()
            In the unlikely case that you want to destroy the perl
            interpreter, here is the corresponding function.

        PerlInterpreter *staticperl
            The perl interpreter pointer used by staticperl. Not normally so
            useful, but there it is.

    bundle.ccopts
        Contains the compiler options required to compile at least bundle.c
        and any file that includes bundle.h - you should probably use it in
        your "CFLAGS".

    bundle.ldopts
        The linker options needed to link the final program.

RUNTIME FUNCTIONALITY
    Binaries created with "mkbundle"/"mkperl" contain extra functions, which
    are required to access the bundled perl sources, but might be useful for
    other purposes.

    In addition, for the embedded loading of perl files to work, staticperl
    overrides the @INC array.

    $file = staticperl::find $path
        Returns the data associated with the given $path (e.g.
        "Digest/MD5.pm", "auto/POSIX/autosplit.ix"), which is basically the
        UNIX path relative to the perl library directory.

        Returns "undef" if the file isn't embedded.

    @paths = staticperl::list
        Returns the list of all paths embedded in this binary.

FULLY STATIC BINARIES - BUILDROOT
    To make truly static (Linux-) libraries, you might want to have a look
    at buildroot (<http://buildroot.uclibc.org/>).

    Buildroot is primarily meant to set up a cross-compile environment
    (which is not so useful as perl doesn't quite like cross compiles), but
    it can also compile a chroot environment where you can use staticperl.

    To do so, download buildroot, and enable "Build options => development
    files in target filesystem" and optionally "Build options => gcc
    optimization level (optimize for size)". At the time of writing, I had
    good experiences with GCC 4.4.x but not GCC 4.5.

    To minimise code size, I used "-pipe -ffunction-sections -fdata-sections
    -finline-limit=8 -fno-builtin-strlen -mtune=i386". The "-mtune=i386"
    doesn't decrease codesize much, but it makes the file much more
    compressible.

    If you don't need Coro or threads, you can go with "linuxthreads.old"
    (or no thread support). For Coro, it is highly recommended to switch to
    a uClibc newer than 0.9.31 (at the time of this writing, I used the
    20101201 snapshot) and enable NPTL, otherwise Coro needs to be
    configured with the ultra-slow pthreads backend to work around
    linuxthreads bugs (it also uses twice the address space needed for
    stacks).

    If you use "linuxthreads.old", then you should also be aware that uClibc
    shares "errno" between all threads when statically linking. See
    <http://lists.uclibc.org/pipermail/uclibc/2010-June/044157.html> for a
    workaround (And <https://bugs.uclibc.org/2089> for discussion).

    "ccache" support is also recommended, especially if you want to play
    around with buildroot options. Enabling the "miniperl" package will
    probably enable all options required for a successful perl build.
    staticperl itself additionally needs either "wget" (recommended, for
    CPAN) or "curl".

    As for shells, busybox should provide all that is needed, but the
    default busybox configuration doesn't include comm which is needed by
    perl - either make a custom busybox config, or compile coreutils.

    For the latter route, you might find that bash has some bugs that keep
    it from working properly in a chroot - either use dash (and link it to
    /bin/sh inside the chroot) or link busybox to /bin/sh, using it's
    built-in ash shell.

    Finally, you need /dev/null inside the chroot for many scripts to work -
    cp /dev/null output/target/dev or bind-mounting your /dev will both
    provide this.

    After you have compiled and set up your buildroot target, you can copy
    staticperl from the "App::Staticperl" distribution or from your perl
    f<bin> directory (if you installed it) into the output/target
    filesystem, chroot inside and run it.

AUTHOR
     Marc Lehmann <schmorp@schmorp.de>
     http://software.schmorp.de/pkg/staticperl.html

Revision:	1.5
Committed:	Tue Dec 7 10:40:39 2010 UTC (15 years, 9 months ago) by root
Branch:	MAIN
CVS Tags:	rel-0_1
Changes since 1.4:	+178 -18 lines
Log Message:	rel-0_1