LibreDWG

LibreDWG - free implementation of the DWG file format

LibreDWG is a free C library to read and write DWG files. This program is part of the GNU project, released under the aegis of GNU. It is licensed under the terms of the GNU General Public License version 3 (or at you option any later version).

DWG is a file format created in the 70's for the emerging CAD applications. Currently it is the native file format of AutoCAD, a proprietary CAD program developed by AutoDesk.

LibreDWG is a fork from LibDWG due to its usage of Esperanto, which we think is not the best strategy for a free software project which aims to get lots of contributors. LibreDWG is written in English. At the moment our decoder (i.e. reader) is done, it can read all DWG versions, just some very advanced R2010+ objects fail to read and are skipped over. The writer is good enough for everything but R2007. R2010-R2018 writing leads to CRC errors still. Among the example applications we wrote using LibreDWG is a reader, a writer, a rewriter (i.e. saveas), an initial SVG and Postscript conversion, dxf and json converters, dwggrep to search for text, and dwglayer to print the list of layers. More are in the pipeline. Please contact us if you want to help.

The strings API is UTF-8 (WTF8 really, Windows UCS-2 has no surrogate pairs), and encodes to the internal 8-bit or UCS-2 strings, depending on the DWG version. Older DWG's are encoded in ~30 codepages, which we convert to unicode/UTF-8.

We also maintain a diff document for our internal fixed ODA-5.4.1 spec at doc/ODA-5.4.2-libredwg-diff.pdf

For security contact file a ticket or email the package maintainers:

Reini Urban

The now inactive founders and previous maintainers were:

Felipe Corrêa da Silva Sanches Rodrigo Rodrigues da Silva Hardeep Singh Rai <hardeep.rai AT gmail DOT com>

If you are looking for general information about the project, check our website: http://www.gnu.org/software/libredwg/

== Building and installing the library ==

You need the following dependencies:

• Basic development tools (a C99 compiler like gcc/clang, make, autoconf, automake and libtool)

Optionally:

• libiconv: optional codepage conversion. without it's just a bit slower.
• libmimalloc: faster memory allocation, but usually not worth the hassle.
• pslib for dwg2ps: http://pslib.sourceforge.net/doc/pslib.html
• pcre2 with 8bit and 16bit libraries for dwggrep regexp support.
• gperf to update static hashes for several API's Only needed when you added objects or changed the dwg.spec significantly
• cmake, ninja
• ODAFileConverter from https://www.opendesign.com/guestfiles/oda_file_converter for doing cross-checks.
• xvfb-run from xvfb/xorg-x11-server-Xvfb for silencing ODAFileConverter popups.
• TeXinfo for building the docs
• SWIG 1.7+
• Python 2.7 or 3.x development headers (debian: python-dev; yum: python-devel) and the libxml2 python bindings.
• Perl 5 for the perl bindings
• doxygen to generate the reference manual
• jq to check json validity, and as dwgfilter backend
• shellcheck to check shell scripts
• rpmlint to check the spec validity
• jinq with some svg11 relaxng to check SVG validity. LaTeXML used to have a broken svg11-basic.rng. If so the zip from http://yupotan.sppd.ne.jp/relax-ng/svg11/ is correct. Needs to be installed into /usr/local/share/relaxng/svg11/ sudo unzip ~/Downloads/svg11-relaxng-20060604.zip -d /usr/local/share/relaxng/ On Ubuntu I needed: apt install jing libjaxp1.3-java libbatik-java libavalon-framework-java
• mapbox/geojsonhint as geojson linter npm install -g @mapbox/geojsonhint
• geojson-validation as 2nd geojson fallback linter npm install -g geojson-validation
• shfmt to format shell scripts
• clang-format to format the C source code
• clang-tidy to check source code
• valgrind to find leaks and memory bugs
• timeout to help tests with large or hanging DWG's
• GNU parallel to speed up special tests (not the moreutils parallel!)
• picat to find unknown fields, a better prolog. http://picat-lang.org/

See INSTALL for generic instructions. Basically, you do:

$ sh ./autogen.sh (if you checked out the source code from git) $ ./configure [--disable-bindings] [--disable-docs] [--disable-shared] $ make $ make check $ sudo make install

This builds and installs various files in the "installation dirs": $libdir ($exec_prefix/lib) -- library files (libredwg.*) $includedir ($prefix/include) -- dwg.h dwg_api.h $libdir/pkgconfig -- libredwg.pc $infodir ($datarootdir/info) -- LibreDWG.info

Use "./configure --help" to see a full list of options you can use to customize the installation dirs. Other options recognized by configure are:

--enable-release

Recommended for packagers and fuzzers. Disables all features
which will not be enabled in official tarball releases. Like skipping
unstable DWG features or objects, unknown DWG versions and objects.

--enable-trace

Enable runtime tracing via LIBREDWG_TRACE (default: no). When
enabled, the environment variable LIBREDWG_TRACE is consulted on
the first decode/encode attempt. Its value is an integer: 0 (no
output) through 9 (full verbosity). Most tools do support a
--verbosity|-v flag instead.

--with-dxf-precision=rfc

How many after-comma places in DXF doubles. 6 is the recommended value (e.g. use rfc), max and the default is 16.

--with-geojson-precision=rfc

How many after-comma places in GeoJSON doubles. 6 is the recommended value by RFC 7946, max and the default is 16.

--disable-write

Disable DWG write support (default: no).
Write support only works for earlier versions until r2004.
Rewriting most DWG's <= r2004 usually works fine.

--disable-bindings

Disable SWIG bindings for python and perl5.

--disable-dxf

Disables all in and out modules: DXF, DXFB, JSON, GeoJSON.

--disable-json

Disables the json in and out modules: JSON, GeoJSON.

--disable-python

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