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

cpanm staticperl

perl -MCPAN -e shell
install staticperl