Builddir

builddir is a little helper tool for C/C++ programmers to manage out-of-source build directories. It manages mappings between build directories and the associated source directories and allows to switch between them.

The provided configure and cmake wrappers additionally ease the configuration by automatically specifying the path to the source directory.

Installation consists out of multiple steps. The first is to install the builddir gem:

gem install builddir

Second, a shell wrapper script (builddir_source_script) has to be placed in the PATH. The script can either be installed by hand (from lib/builddir/data) or can be generated using the builddir_generate_source_script command.

builddir_generate_source_script ~/bin/builddir_source_script

Third, to make builddir intuitively usable it is recommended to define the following bash aliases.

alias builddir='source builddir_source_script'
alias bdir='builddir'
alias cds='builddir -s'
alias cdb='builddir -cb'
alias cmake='builddir_cmake'
alias configure='builddir_configure'

Fourth, define the build directory root by exporting the DEFAULT_BUILDDIR environment variable. When DEFAULT_BUILDDIR is not defined then /tmp/builddir is used as default.

export DEFAULT_BUILDDIR="<path to the builddir>"

It is highly recommended to add the alias definitions and the environment variable definition to the configuration file (~/.bashrc, ~/.zshrc.local, ...) of the used shell to make them permanent.

The following sections describe the most common operations briefly assuming that the recommended aliases have been configured.

cdb [baseName] looks up the current directory as source directory and changes to the associated build directory. If no mapping could be found then a new one is created considering the optional basename.

cds looks up the current directory as build directory and changes to the associated source directory. An error is returned if no mapping could be found.

The configuration of an out-of-source build requires the path to the source directory. Wrapper scripts for the most common build systems are provided which automatically specify this path when needed. It is therefore possible to simply call configure [options] or cmake [options] in the build directory without any source path.

Cross compilation with cmake usually requires a toolchain file which is often distributed with the source code itself. Using such a file requires the specification of the full path which kind of defeats the purpose of the wrapper. Therefore, an additional option -A <ARCH_NAME> has been added which expands into -DCMAKE_TOOLCHAIN_FILE=<src_dir>/cmake/toolchain/<ARCH_NAME>.cmake.

The bdir command supports further operations like the deletion of mappings or the purging of the build directory root from abandoned directories. The flags for these and other operations can be found in the help of the command. (bdir --help)

• add unit tests
• support multiple build directories?