The CRE2 distribution is a C language wrapper for the RE2 library, which is implemented in C++. RE2 is a fast, safe, thread-friendly alternative to backtracking regular expression engines like those used in PCRE, Perl, and Python.
This distribution makes use of the GNU Autotools; it relies on
pkg-config to find the installed re2 library. The last time the
maintainer updated this paragraph, he had tested this package with a
release of RE2 2024-07-02.
Copyright (c) 2012, 2013, 2015-2017, 2019, 2024 Marco Maggi mrc.mgg@gmail.com
Copyright (c) 2011 Keegan McAllister
All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
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Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
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Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
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Neither the name of the author nor the names of his contributors may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
To install from a proper release tarball, do this:
$ cd cre2-0.1.0
$ mkdir build
$ cd build
$ ../configure
$ make
$ make check
$ make install
to inspect the available configuration options:
$ ../configure --help
The Makefile is designed to allow parallel builds, so we can do:
$ make -j4 all && make -j4 check
which, on a 4-core CPU, should speed up building and checking significantly.
The Makefile supports the DESTDIR environment variable to install files in a temporary location, example: to see what will happen:
$ make -n install DESTDIR=/tmp/cre2
to really do it:
$ make install DESTDIR=/tmp/cre2
After the installation it is possible to verify the installed library against the test suite with:
$ make installcheck
From a repository checkout or snapshot (the ones from the Github site): we must install the GNU Autotools (GNU Automake, GNU Autoconf, GNU Libtool), then we must first run the script "autogen.sh" from the top source directory, to generate the needed files:
$ cd cre2
$ sh autogen.sh
notice that autogen.sh will run the programs autoreconf and
libtoolize; the latter is selected through the environment variable
LIBTOOLIZE, whose value can be customised; for example to run
glibtoolize rather than libtoolize we do:
$ LIBTOOLIZE=glibtoolize sh autogen.sh
After this the procedure is the same as the one for building from a proper release tarball, but we have to enable maintainer mode:
$ ../configure --enable-maintainer-mode [options]
$ make
$ make check
$ make install
Read the documentation.
RE2 is a Google project. CRE2 is based on code by Keegan McAllister. This distribution was assembled by Marco Maggi.
Matthew Hall (https://github.com/megahall) contributed miscellaneous fixes.
Maksym Melnychok (https://github.com/keymone) contributed a fix for wrong usage of variable-length arrays.
afiaux (https://github.com/afiaux) contributed the RE2:Set() interface.
Guillaume Massé (https://github.com/MasseGuillaume) contributed fixes
and the implementation of cre2_find_named_capturing_groups().
Will Speak (https://github.com/iwillspeak) contributed the implementation of the named capturing groups iterator.
Bug and vulnerability reports are appreciated, all the vulnerability reports are public; register them at the Issue Tracker at the project's Github site. For contributions and patches please use the Pull Requests feature at the project's Github site.
This may be a challenge, depending on how much of a cmake connoisseur we are.
In general, we have to remember that: if we install both the shared and the static libraries: when compiling with common command line options, the static libraries will take precedence. This package is meant to be used with shared libraries, but it should work fine with static libraries, too.
Let's suppose we want to install all the packages under the directory "/opt/re2/2024-07-02"; on a Unix system, we will need to put in some profile configuration file something like:
RE2_PREFIX=/opt/re2/2024-07-02
RE2_LIBDIR=${RE2_PREFIX}/lib64
export LD_LIBRARY_PATH=${RE2_LIBDIR}:$LD_LIBRARY_PATH
export PKG_CONFIG_PATH=${RE2_LIBDIR}/pkgconfig:$PKG_CONFIG_PATH
as a first attempt: no other search path should be upgraded, let's leave to the packages to find include files and everything else.
When configuring, building and installing the prerequisite package
abseil we should follow the instructions in its README file; but here
is a hint to configure the package to build shared libraries:
$ cmake . \
--install-prefix "$RE2_PREFIX" \
-DCMAKE_BUILD_TYPE=RelWithDebInfo \
-DCMAKE_CXX_FLAGS:STRING="-fPIC" \
-DCMAKE_CXX_STANDARD=17 \
-DBUILD_SHARED_LIBS=ON \
-DCMAKE_BUILD_TYPE=Release \
-DABSL_PROPAGATE_CXX_STD=ON
When configuring, building and installing the prerequisite package
googletest we should follow the instructions in its README file; but
here is a hint to configure the package to build shared libraries:
$ cmake . \
--install-prefix "$RE2_PREFIX" \
-DBUILD_SHARED_LIBS=ON \
-DCMAKE_CXX_FLAGS:STRING="-fPIC"
When configuring, building and installing the package re2 itself we
should follow the instructions in its README file; but here is a hint to
configure the package to build shared libraries:
$ cmake . \
--install-prefix "$RE2_PREFIX" \
-DBUILD_SHARED_LIBS=ON \
-DCMAKE_CXX_FLAGS:STRING="-fPIC" \
-DCMAKE_BUILD_TYPE=Release
The latest release of this package can be downloaded from:
https://bitbucket.org/marcomaggi/cre2/downloads
development takes place at:
http://github.com/marcomaggi/cre2/
and as backup at:
https://bitbucket.org/marcomaggi/cre2/
the documentation is available online:
http://marcomaggi.github.io/docs/cre2.html
the GNU Project software can be found here: