Dynamic bitarray implementation written in C.
This bitarray/bitset implementation supports plenty of bitarray-relevant features, such as
- clearing/setting bit (ranges)
- fast counting of set bits in a range or the entire bitarray
&(AND),|(OR),^(XOR),~(NOT),>>(RIGHT SHIFT) and<<(LEFT SHIFT) on bitarrays- converting an (unsigned) number/string to a bitarray for easy bit manipulation
- converting a bitarray into a number or string
amongst others.
Unlike e.g. C++'s std::bitset, this bitarray implementation is dynamic, meaning the size of a bitarray doesn't need to be known at compile-time, which allows for some more flexibility.
This repo provides three installation methods:
You can directly include bitarray.h into your .c file as a header-only "library". Simply add #include "bitarray.h" at the top of your .c file and compile it:
BIT_ARRAY_PATH=/path/to/this/repo
gcc -o mybinary -I$BIT_ARRAY_PATH main.c
It is recommended to also add the -march=native option to leverage optimized functions/assembly instructions for your specific machine.
Alternatively you can produce an bitarray.o file by executing the command
make default
which you can simply link/combine with your binary:
BIT_ARRAY_PATH=/path/to/this/repo
gcc -I$(BIT_ARRAY_PATH) -o mybinary main.c path/to/bitarray.o
If you choose this method, make sure to include the libbitarray.h header file at the top of your main .c file instead of the bitarray.h header file to avoid linker errors.
The 3rd option is to create a shared library with the command
make shared
This will produce a libbitarray.so file, which you can link against.
To avoid linker errors, make sure to add the path where the libbitarray.so file is located to the LD_LIBRARY_PATH variable.
export LD_LIBRARY_PATH=/path/to/dir/of/libbitarray.so:$LD_LIBRARY_PATH
BIT_ARRAY_PATH=/path/to/this/repo
gcc -L/path/to/dir/of/libbitarray.so -I$BIT_ARRAY_PATH -o mybinary -lbitarray main.c
Again, make sure to include the libbitarray.h header file at the top of your main .c file instead of the bitarray.h header file to avoid linker errors.
By default, no bounds checking is performed in any of the functions to ensure maximum speed/performance. However, if you compile/link using the Makefile targets debug instead of default or debug_shared instead of shared, assert statements will be triggered if you attempt to access an out-of-bounds bit.
You can also run a small but thorough test program to check if everything works by executing the command
make test && ./test
I primarily wrote this implementation for practice reasons, so please feel free to open issues if you encounter any bugs or other problems.