Look for the shared library suffix of the platform

Only reached on platforms other than MacOS, which has its own branch, but the
hard coded .so has no business there either.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Change-Id: Ie092e28542768d1da90312cc0d9900b2f64fc7d2
1 file changed
tree: 4708f1a863054f175d7b202b69c5a5f5a2513f30
  1. .idea/
  2. ci/
  3. examples/
  4. extras/
  5. src/
  6. tests/
  7. tools/
  8. .gitignore
  9. .gitlab-ci.yml
  10. CMakeLists.txt
  11. README.md
README.md

CollocatorDB: Storing and retrieving collocation counts based on RocksDB

Installation

Install RocksDB and prerequisites

The rocksdb of the distribution is used, no particular version is required.

  • on Fedora, Rocky Linux, RHEL

    sudo dnf install cmake gcc-c++ rocksdb-devel snappy-devel zlib-devel bzip2-devel lz4-devel libzstd-devel gflags-devel
    
  • on Ubuntu, Debian

    sudo apt-get install cmake librocksdb-dev libgflags-dev libsnappy-dev zlib1g-dev libbz2-dev liblz4-dev libzstd-dev libomp-dev
    
  • on MacOS

    brew install cmake rocksdb snappy zlib bzip2 lz4 zstd libomp gflags
    

Do not install another rocksdb below /usr/local next to the packaged one. The compiler looks into /usr/local/include before /usr/include, so its headers would be used while the library of the distribution is linked, which ends in a long list of undefined references. The build compares the version of the headers with the version of the library and stops with an explanation when they do not match.

Install CollocatorDB

git clone "https://korap.ids-mannheim.de/gerrit/ids-kl/collocatordb"
cd collocatordb
mkdir -p build
cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr/local ..
make && sudo make install && sudo ldconfig
ctest --extra-verbose

The tests run after the installation, not before: one of them calls the collocatordb_query tool, which is built with the rpath of its install location and does not find the library as long as it is not installed. The build directory has to be build inside the sources, the tests look for the tool and for their data relative to it.

Static library

libcollocatordb_static.a is built as well. It is linked against the shared rocksdb unless a static rocksdb is found, which is enough for most purposes. A static rocksdb is only needed to link a program completely statically, as dereko2vec does, which is worth about 10% on collocator lookups.

Debian and Ubuntu ship librocksdb.a in librocksdb-dev, so there is nothing to do. Fedora, Rocky Linux and RHEL do not ship one, so it has to be built. Keep it out of /usr/local, where its headers would shadow those of the package, and point the build at it:

git clone https://github.com/facebook/rocksdb.git -b v$(rpm -q --qf '%{VERSION}' rocksdb) --single-branch
cd rocksdb
make -j $(nproc) static_lib
make install-static INSTALL_PATH=$HOME/rocksdb-static
cd ../collocatordb/build
cmake -DROCKSDB_STATIC=$HOME/rocksdb-static/lib/librocksdb.a -DCMAKE_INSTALL_PREFIX=/usr/local ..
make && sudo make install && sudo ldconfig

Provided API

typedef struct {
  uint32_t w2;
  uint64_t f2;
  uint64_t raw;
  double pmi;
  double npmi;
  double llr;
  double lfmd;
  double md;
  double md_nws;
  uint64_t left_raw;
  uint64_t right_raw;
  double left_pmi;
  double right_pmi;
  double dice;
  double logdice;
  double ldaf;
  int window;
  int af_window;
} COLLOCATOR ;

COLLOCATORDB *open_collocatordb(const char *s);
COLLOCATORDB *open_collocatordb_for_write(const char *s);
void inc_collocator(COLLOCATORDB *db, uint64_t w1, uint64_t w2, int8_t dist);
void dump_collocators(COLLOCATORDB *db, uint32_t w1, uint32_t w2, int8_t dist);
COLLOCATOR *get_collocators(COLLOCATORDB *db, uint32_t w1);
COLLOCATOR *get_collocation_scores(COLLOCATORDB *db, uint32_t w1, uint32_t w2);
char *get_collocators_as_json(COLLOCATORDB *db, uint32_t w1);
char *get_collocation_scores_as_json(COLLOCATORDB *db, uint32_t w1, uint32_t w2);
char *get_word(COLLOCATORDB *db, uint32_t w1);
void read_vocab(COLLOCATORDB *db, char *fname);
char *get_version();
uint64_t get_word_id(COLLOCATORDB *db, const char *word);
uint64_t get_corpus_size(COLLOCATORDB *db);
uint64_t get_word_frequency(COLLOCATORDB *db, uint64_t w);

Changes

  • v1.5.0 (2026-07-31)

    • fixed two memory leaks in the collocator lookup, a rocksdb iterator and the window sums, together 3.6 kB per call
    • builds against the rocksdb of the distribution, no rocksdb 5.11 from source anymore. Verified with 7.8 (Debian), 10.2 (Fedora) and 11.0 (Alpine); existing databases stay readable
    • needs C++17, and C++20 for rocksdb 11 and newer
    • added get_corpus_size(), which returns the total token count
    • added get_word_frequency(), which returns the absolute frequency of a word in the corpus
  • v1.4.0 (2024-11-23)

    • added collocatordb_query command line tool
    • added get_word_id(), which returns the ID of a word
    • added md_nws MI² score based on nominal window size (=10) instead of actual window size, for which only positions are counted where the collocate actually occurs
  • v1.3.2 (2024-11-15)

    • added get_version(), which returns version string
  • v1.3.1 (2024-11-14)

    • fixed calculation of total token count

TODO

  • extend API
  • add more unit tests

License

Based on RocksDB, CollocatorDB is dual-licensed under both the GPLv2 (found in the COPYING file in the root directory) and Apache 2.0 License (found in the LICENSE.Apache file in the root directory). You may select, at your option, one of the above-listed licenses.