Copyright (C) 1994, 1995, 1996, 1999, 2000, 2001, 2002 Free Software
Foundation, Inc.

   This file is free documentation; the Free Software Foundation gives
unlimited permission to copy, distribute and modify it.

Project-specific install (this tree)
====================================

   This tree is librsvg 2.62.3 (`librsvg-2.0`).  The public name,
   soname, and pkg-config module remain librsvg-2.0.

   libxml2 2.15 builds without a port patch.  When xmlParserMaxDepth
   is a writable global, the in-tree raise keeps default text/entity
   caps (no XML_PARSE_HUGE).  When it is a macro (256), parse options
   include XML_PARSE_HUGE.  xml-stylesheet uses xmlReadMemory
   (length is strlen, no extra NUL).

   `make install` is the supported way to install the library after
   you have built it.  Use `DESTDIR` when you are packaging, or when
   this machine already has another librsvg-2.0 that you must not
   replace.

Normal install
--------------

     ./configure --prefix=/usr \
       --disable-introspection \
       --disable-vala
     make
     make install

   Default prefix is `/usr/local` if you omit `--prefix`.

   `install-sh` at the project root is the Autotools helper that
   `make install` invokes.  Do not run it by hand.

Staged / package install
------------------------

   If a system librsvg-2.0 is already in use (GTK, gdk-pixbuf loader,
   desktop icons), install into a staging directory instead of the
   live prefix:

     ./configure --prefix=/usr \
       --disable-introspection \
       --disable-vala
     make
     make DESTDIR="$PWD/stage" install

   Files land under `stage/` (for example `stage/usr/lib`).  Install
   that tree with your package manager, or test it without touching
   `/usr`:

     STAGE="$PWD/stage"
     export LD_LIBRARY_PATH="$STAGE/usr/lib"
     export GDK_PIXBUF_MODULE_FILE="$STAGE/usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders.cache"
     "$STAGE/usr/bin/rsvg-convert" icon.svg -o /tmp/out.png

   The hook in `gdk-pixbuf-loader/` writes a staged `loaders.cache`
   when DESTDIR is set.  It does not update the host cache.
   Packages must not ship `usr/lib/gdk-pixbuf-2.0/*/loaders.cache`
   (gdk-pixbuf owns that path).  After installing the package, run
   `gdk-pixbuf-query-loaders --update-cache` (or the distro
   equivalent).  A package recipe should delete the staged cache
   before tarring.  First install is `pkgadd` without `-u`; use `-u`
   only when upgrading.

Rebuild
-------

   For a rebuild, use `make clean` then `make`.  `make distclean`
   is configure-level: it removes Makefiles and config.status.  It
   must not wipe shipped Doxygen HTML or other git-tracked docs.

CSS engine
----------

   Stylesheets use in-tree **css/** only.  `libcroco/` is an unbuilt
   archive (not compiled, not linked, not packaged).
   `--enable-croco` / `--disable-croco` error: libcroco is
   discontinued.  A system libcroco is not used.  `RSVG_CSS_ENGINE`
   is ignored.

Default DPI
-----------

   Default DPI is 96 for `RsvgHandle` and `rsvg-convert`.
   Use `rsvg-convert -d 90 -p 90` for the previous CLI default.

Raster decoders in SVG `<image>`
--------------------------------

   Defaults are **auto**:

     --disable-png / --disable-jpeg / --disable-gif /
     --disable-webp / --disable-bmp / --disable-avif
     omit that decoder
     --enable-*  without the library is an error for
     PNG/JPEG/GIF/WebP/AVIF
     (BMP is in-tree; --enable-bmp needs no extra library)

   PNG uses libpng, JPEG uses libjpeg or libjpeg-turbo, GIF uses
   giflib, WebP uses libwebp, BMP uses an in-tree decoder, AVIF
   uses libavif (`pkg-config libavif`).  `libpixbufloader-svg.so`
   is unchanged.

   SVG `<image>` rasters: maximum side 32767, maximum 32×1024×1024
   pixels.  Very large `data:` payloads or stylesheet buffers may
   be rejected.

Tests and docs
--------------

   `make check` runs the test suite.  Optional `make fuzz-css`,
   `make fuzz-afl`, and `make fuzz-bmp` are not part of `make check`.
   `make fuzz-afl` skips if AFL++ is not installed.

   API HTML is generated with Doxygen.  If `doxygen` is missing,
   HTML generation is skipped.

     doxygen doc/Doxyfile
     # or: make html

   Output is `doc/html/` (`index.html`, `examples.html`).
   When published under `doc/`, the project name links to the parent
   site index (`../index.html`).

   Licences: see `COPYING`.  The library is GNU Library GPL v2 or
   later (`LICENCE-LIB`).  Tools are GNU GPL v2 (`LICENCE`).

   The rest of this file is the generic Autotools text.


Basic Installation
==================

   These are generic installation instructions.

   The `configure' shell script attempts to guess correct values for
   various system-dependent variables used during compilation.  It uses
   those values to create a `Makefile' in each directory of the package.
   It may also create one or more `.h` files containing system-dependent
   definitions.  Finally, it creates a shell script `config.status` that
   you can run in the future to recreate the current configuration, and a
   file `config.log` containing compiler output (useful mainly for
   debugging `configure').

   It can also use an optional file (typically called `config.cache'
   and enabled with `--cache-file=config.cache' or simply `-C') that saves
   the results of its tests to speed up reconfiguring.  (Caching is
   disabled by default to prevent problems with accidental use of stale
   cache files.)

   If you need to do unusual things to compile the package, please try
   to figure out how `configure' could check whether to do them, and mail
   diffs or instructions to the address given in the `README' so they can
   be considered for the next release.  If you are using the cache, and at
   some point `config.cache' contains results you don't want to keep, you
   may remove or edit it.

   The file `configure.ac' (or `configure.in') is used to create
   `configure' by a program called `autoconf'.  You only need
   `configure.ac' if you want to change it or regenerate `configure' using
   a newer version of `autoconf'.

The simplest way to compile this package is:

  1. `cd' to the directory containing the package's source code and type
     `./configure' to configure the package for your system.  If you're
     using `csh' on an old version of System V, you might need to type
     `sh ./configure' instead to prevent `csh' from trying to execute
     `configure' itself.

     Running `configure' takes awhile.  While running, it prints some
     messages telling which features it is checking for.

  2. Type `make' to compile the package.

  3. Optionally, type `make check' to run any self-tests that come with
     the package.  Optional fuzz targets (`make fuzz-css',
     `make fuzz-afl', `make fuzz-bmp') are not part of `make check`.

  4. Type `make install' to install the programs, library, and
     documentation into the prefix chosen by `configure` (default
     `/usr/local`).  To stage files for a package, or to avoid
     replacing a live system librsvg-2.0, use:

        make DESTDIR="$PWD/stage" install

     `install-sh` is used by that target; do not run it by hand.

  5. You can remove the program binaries and object files from the
     source code directory by typing `make clean`.  To also remove the
     files that `configure` created (so you can compile the package for
     a different kind of computer), type `make distclean`.  There is
     also a `make maintainer-clean` target, but that is intended mainly
     for the package's developers.  If you use it, you may have to get
     all sorts of other programs in order to regenerate files that came
     with the distribution.

Compilers and Options
=====================

   Some systems require unusual options for compilation or linking that
   the `configure' script does not know about.  Run `./configure --help'
   for details on some of the pertinent environment variables.

   You can give `configure' initial values for configuration parameters
   by setting variables in the command line or in the environment.  Here
   is an example:

     ./configure CC=c89 CFLAGS=-O2 LIBS=-lposix

   *Note Defining Variables::, for more details.

Compiling For Multiple Architectures
====================================

   You can compile the package for more than one kind of computer at the
   same time, by placing the object files for each architecture in their
   own directory.  To do this, you must use a version of `make' that
   supports the `VPATH' variable, such as GNU `make`.  `cd' to the
   directory where you want the object files and executables to go and run
   the `configure' script.  `configure' automatically checks for the
   source code in the directory that `configure' is in and in `..`.

   If you have to use a `make' that does not support the `VPATH'
   variable, you have to compile the package for one architecture at a
   time in the source code directory.  After you have installed the
   package for one architecture, use `make distclean' before reconfiguring
   for another architecture.

Installation Names
==================

   By default, `make install' will install the package's files in
   `/usr/local/bin', `/usr/local/man', etc.  You can specify an
   installation prefix other than `/usr/local' by giving `configure' the
   option `--prefix=PATH'.

   You can specify separate installation prefixes for
   architecture-specific files and architecture-independent files.  If you
   give `configure' the option `--exec-prefix=PATH', the package will use
   PATH as the prefix for installing programs and libraries.
   Documentation and other data files will still use the regular prefix.

   In addition, if you use an unusual directory layout you can give
   options like `--bindir=PATH' to specify different values for particular
   kinds of files.  Run `configure --help' for a list of the directories
   you can set and what kinds of files go in them.

   If the package supports it, you can cause programs to be installed
   with an extra prefix or suffix on their names by giving `configure' the
   option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.

Optional Features
=================

   Some packages pay attention to `--enable-FEATURE' options to
   `configure', where FEATURE indicates an optional part of the package.
   They may also pay attention to `--with-PACKAGE' options, where PACKAGE
   is something like `gnu-as' or `x' (for the X Window System).  The
   `README' should mention any `--enable-' and `--with-' options that the
   package recognizes.

   For packages that use the X Window System, `configure' can usually
   find the X include and library files automatically, but if it doesn't,
   you can use the `configure' options `--x-includes=DIR' and
   `--x-libraries=DIR' to specify their locations.

Specifying the System Type
==========================

   There may be some features `configure' cannot figure out
   automatically, but needs to determine by the type of machine the package
   will run on.  Usually, assuming the package is built to be run on the
   _same_ architectures, `configure' can figure that out, but if it prints
   a message saying it cannot guess the machine type, give it the
   `--build=TYPE' option.  TYPE can either be a short name for the system
   type, such as `sun4', or a canonical name which has the form:

     CPU-COMPANY-SYSTEM

where SYSTEM can have one of these forms:

     OS KERNEL-OS

   See the file `config.sub' for the possible values of each field.  If
   `config.sub' isn't included in this package, then this package doesn't
   need to know the machine type.

   If you are _building_ compiler tools for cross-compiling, you should
   use the `--target=TYPE' option to select the type of system they will
   produce code for.

   If you want to _use_ a cross compiler, that generates code for a
   platform different from the build platform, you should specify the
   "host" platform (i.e., that on which the generated programs will
   eventually be run) with `--host=TYPE'.

Sharing Defaults
================

   If you want to set default values for `configure' scripts to share,
   you can create a site shell script called `config.site' that gives
   default values for variables like `CC`, `cache_file`, and `prefix`.
   `configure' looks for `PREFIX/share/config.site' if it exists, then
   `PREFIX/etc/config.site' if it exists.  Or, you can set the
   `CONFIG_SITE' environment variable to the location of the site script.
   A warning: not all `configure' scripts look for a site script.

Defining Variables
==================

   Variables not defined in a site shell script can be set in the
   environment passed to `configure'.  However, some packages may run
   configure again during the build, and the customized values of these
   variables may be lost.  In order to avoid this problem, you should set
   them in the `configure' command line, using `VAR=value'.  For example:

     ./configure CC=/usr/local2/bin/gcc

will cause the specified gcc to be used as the C compiler (unless it is
overridden in the site shell script).

`configure' Invocation
======================

   `configure' recognizes the following options to control how it
   operates.

`--help'
`-h'
     Print a summary of the options to `configure', and exit.

`--version'
`-V'
     Print the version of Autoconf used to generate `configure', and exit.

`--cache-file=FILE'
     Enable the cache: use and save the results of the tests in FILE,
     traditionally `config.cache'.  FILE defaults to `/dev/null' to
     disable caching.

`--config-cache'
`-C'
     Alias for `--cache-file=config.cache'.

`--quiet'
`--silent'
`-q'
     Do not print messages saying which checks are being made.  To
     suppress all normal output, redirect it to `/dev/null' (any error
     messages will still be shown).

`--srcdir=DIR'
     Look for the package's source code in directory DIR.  Usually
     `configure' can determine that directory automatically.

`configure' also accepts some other, not widely useful, options.  Run
`configure --help' for more details.
