How to use hdfk library into qt? - c++

Question

How can I use HKDF library in my qt project? I found this library seems appropriate in qt (I checked with my source), but I couldn't include this header to project.

Answer 1

Adding a library to a Qt project is actually quite simple. In your qmake .pro file you need the following:
# This is the search location for the compiler to look for headers that accompany your library.
# For system libraries that typically resides under **/usr/include** or **/usr/local/include** if you used `make install`.
INCLUDEPATH+="/path/of/headers/for/library"
# This is the search location for the compiler/linker to look for the library itself.
# For system libraries this is usually somewhere under **/usr/lib** or **/usr/local/lib**
LIBS+= -L/path/of/library/itself
# This is the name of the library to include at link time
# without the **lib** prefix and the **.so** / **.a** / **.lib** / **.dll** extension.
LIBS+= -lMyLibraryName
# This is the full path of the library file itself
# *including* the aforementioned **lib** prefix and the **.so** / **.a** / **.lib** / **.dll** extension.
# This is used by qmake to look for changes to the library at build time,
# to make sure it is re-linked on change and other dependency related stuff
PRE_TARGETDEPS += /path/and/filename/of/library/itself/libMyLibraryName.lib
TIP: All the paths, unless they are specified as absolute paths (starting with '/') will be relative to the build directory. This might be the project directory, but in the case of shadow builds, it will be the shadow build directory. As a tip, simply prepend the following to your relative paths to make them relative to project directory: $$_PRO_FILE_PWD_/ so if for example your lib resides in /my/qt/project/libs/mylib you could make your project resilient to moving by using $$_PRO_FILE_PWD_/libs/mylib instead. Please note that the "project dir" is the location of the qmake .pro file.

Answer 2

I use CryptoPP HKDF implementation by https://www.cryptopp.com
Firstly, build static lib for valid architecture and for your platform (MacOS, Android, iOS, etc). CryptoPP Wiki has working manuals and scripts.
Then, just add 2 lines to your qmake *.pro file:
INCLUDEPATH += $$DEV_LIBS_PATH/cryptopp/$$ANDROID_ARCH/include
LIBS += -L$$DEV_LIBS_PATH/cryptopp/$$ANDROID_ARCH/lib -lcryptopp
as you can understand, I used qmake variables DEV_LIBS_PATH and ANDROID_ARCH which are just compose right path to relevant headers and static library libcryptopp.a.