找不到Openssl标头-错误

Question

I need to compile a libwebsocket library for my ARM target which requires openssl for its functioning. I am getting following error when i build latest libwebsocket at the time of, cmake ...

But openssl is installed here

whereis openssl
openssl: /usr/bin/openssl /usr/bin/X11/openssl /usr/share/man/man1/openssl.1ssl.gz

=================================== Error ================

-- Looking for 4 include files stdlib.h, ..., float.h - found
-- Found ZLIB: /usr/lib/arm-linux-gnueabihf/libz.so (found version "1.2.7") 
ZLib include dirs: /usr/include
ZLib libraries: /usr/lib/arm-linux-gnueabihf/libz.so
Compiling with SSL support
CMake Error at /usr/local/share/cmake-2.8/Modules/FindPackageHandleStandardArgs.cmake:97 (message):
  Could NOT find OpenSSL, try to set the path to OpenSSL root folder in the
  system variable OPENSSL_ROOT_DIR (missing: OPENSSL_LIBRARIES
  OPENSSL_INCLUDE_DIR)
Call Stack (most recent call first):
  /usr/local/share/cmake-2.8/Modules/FindPackageHandleStandardArgs.cmake:291 (_FPHSA_FAILURE_MESSAGE)
  /usr/local/share/cmake-2.8/Modules/FindOpenSSL.cmake:313 (find_package_handle_standard_args)
  CMakeLists.txt:436 (find_package)


-- Configuring incomplete, errors occurred!

======================================= openssl is here ========================

ignite@ignite:~/sbox2/rootfs/rfs-raspbian_2/home/pi/libwebsockets/build$  whereis openssl
openssl: /usr/bin/openssl /usr/bin/X11/openssl /usr/share/man/man1/openssl.1ssl.gz

actually i have, source tarball from here. it have configure script to make & make install http://www.openssl.org/source/
openssl-1.0.1e.tar.gz

So with this (openssl-1.0.1e.tar.gz) will be the right package to get --> openssl-dev or openssl-devel --- so that i can resolve this error ?

Answer 1

So with this (openssl-1.0.1e.tar.gz) will be the right package to get --> openssl-dev or openssl-devel --- so that i can resolve this error ?

The openssl-dev packages are for development on the host machine (which is probably x86 or x64 family). You need a cross compiled library for the target (and not the host). So openssl-dev will probably not solve your problem.

Are you targeting a generic ARM processor, iOS, or Android? If the former, you will need an arm cross-toolchain with paths set appropriately. I'm not aware of a good tutorial on cross compiling the library (and I've suffered it in the past).

There are some prebuilt configurations for generic cross compiling. Open Configure and config , and look at some of the triples. (OpenSSL does not use Automake and friends).

If iOS or Android, the OpenSSL wiki has some examples of cross compiling for the platforms. See, for example, FIPS Library and Android . The setenv-android.sh script is most important because it set paths, sysroot and toolchains. Once paths and toolschains are set, the rest is easy.

If you are targeting a generic ARM, then you could use the Android setenv-android.sh as a starting point for your generic build. Once you complete the build, then point OPENSSL_ROOT_DIR into the install directory for ARM.