Expanded support for user-defined types

• Support for user-defined compound HDF5 types
• Support for HDF5 Tables with user-defined compound HDF5 types as entries

See examples 5 and 6 in the wiki for more details

Large update

Rewrite of fundamental parts of h5pp adding many features without breaking API for older versions

For users

• Users can now query type information and size of datasets and attributes before reading
• Users can now select layout H5D_COMPACT, H5D_CONTIGUOUS and H5D_CHUNKED directly when writing a new dataset
• Users can specify chunking dimensions when writing a new H5D_CHUNKED dataset. If not specified, these dimensions will be computed.
• Users can now set default compression level or specify one directly when writing a dataset
• Users can now opt in to dependencies like Eigen3 and spdlog
• Added support for types "long double" and "short"
• Clarified many debugging messages

Internal

• New wrapper classes for HDF5 "hid_t" identifiers. These identifiers are numbers that are analogous to pointers, they need to be managed (created/destroyed) by the user. To avoid resource leaks, the new wrapper class manages the life-time of these identifiers in a type-safe way
• New non-owning wrapper for c-style arrays
• Reorganisation of namespaces and better naming convention
• Many new sfinae helper template functions to scan data types
• More precise scan of type info before reading/writing/bootstrapping
• Eliminated need for experimental/type_traits header by rewriting sfinae functions
• New ctests for typeinfo

Compatibility update

Major

• Added compatibility with Windows (MSVC)
• Added compatibility with Mac OSX
• Added ghc::filesystem as drop-in replacement for compilers where std::filesystem is missing
• Mimic std::experimental::is_detected on compilers where experimental/type_traits is missing

Minor

• Added CI testing for windows and osx for various download methods.
• Added "find-only" as download method.
• Print type information for debugging

First stable release

• Cleaned up conan related build code
• Simplified linking of targets
• Expanded on usage examples and explanation of linking in README.md
• Updated the name of member functions writeAttributeToLink() to writeAttribute() to follow naming convention
• New conan repo for h5pp: https://bintray.com/davidace/conan-public/h5pp%3Adavidace
• New DOWNLOAD_METHOD selection method to choose between "none", "conan" and "native" download methods for dependencies
• New conanfile.py recipe added.

Support for reading attributes

New features:

• Added support for reading attributes h5pp::File::readAttribute(DataType &data, const std::string &attributeName, const std::string &linkPath).
• Added function to list all attributes std::vector<std::string> h5pp::File::getAttributeNames(const std::string &linkPath)

Improvements:

• Corrected size for char arrays using strlen instead of size.
• Stronger testing for reading and writing attributes
• Target-based robust transitive linking for hdf5

Resolved static linking errors related to pthread

• Bug fix: The h5pp_DIR directory is now inserted into CMAKE_MODULE_PATH instead of appended, to prioritize finding the hand-made Find modules which are included with h5pp.
• Use "pthread" instead of "-lpthread" when linking to avoid downstream errors. When linking statically, one may need -Wl, --whole-archive phread -Wl,--no-whole-archive as described in stackoverflow. If we mix "-lpthread" and "pthread" and then --whole-archive, CMake is not smart enough to unify the link flags and gives a multiple definition error. Sticking to "pthread" seems most flexible since CMake can add "-l" as needed.
• Preempt Threads::Threads setting it to link "pthread" if not defined already.

Tweak release + bugfix

Re-release of v0.4.7 due to find_package module bugfix

• CMAKE_MODULE_PATH needs h5pp_DIR first to give hand made modules priority
• Controllable parallel build command
• Put an upper cap on number of cores when building in ci testing
• Use tar.gz sources instead of git when possible
• Print nicer host properties
• Better printout messages when building dependencies
• Better honor install location of dependencies
• Changed default install dir for examples to share/h5pp/examples
• Avoid overwriting HDF5_ROOT
• Check that version files for dependencies exist before reading

Continued work on adding robustness to find/link steps

• Added Findspdlog.cmake in the same style as FindEigen3.cmake
• Added version check for spdlog to avoid ubuntu xenial apt version which is too old
• Replaced Threads::Threads with -lpthread because for some reason that causes less linking problems when h5pp is linked from other projects.

Improved support for finding and overriding search paths for dependencies

• h5pp now supports spdlog with external fmt and compiled library to speed up compile times.
• Corrected header includes for spdlog relating to fmt. Headers are included differently if fmt is extrnal.
• Eigen can be found in given directories with override mechanism by defining variables such as Eigen3_DIR or EIGEN3_ROOT. The found path gets exported in H5PP_DIRECTORY_HINTS. This is useful when compiling with conan/conda external dependencies.
• h5pp can now be built with conan-only dependencies

Updated cmake find flexibility

Big update to the functionality of find_package(H5PP)

• Added support for COMPONENTS and REQUIRED and QUIET in find_package(h5pp) when searching for h5pp and its dependencies. Valid components are EIGEN3, SPDLOG, HDF5, NONE and/or ALL. Example: find_package(h5pp 0.4.4 COMPONENTS EIGEN3 SPDLOG QUIET)
• If no COMPONENTS are specified the default is to look for all dependencies.
• Modernized travis-ci testing script
• New more robust search behavior when looking for HDF5 in various places /conda/apt/prefix/HDF5_ROOT...)
• Enabled C language when searching for HDF5 C components