CMakeLists: Allow use as a library (#82)

This allows TrezorCrypto to be linked with by other CMake projects

.travis.yml

@@ -3,8 +3,12 @@ language: c
 
 addons:
   apt:
+    sources:
+    - george-edison55-precise-backports # CMake 3.x
     packages:
     - check
+    - cmake # Travis CI comes with CMake 2.8.7, we need CMake 2.8.11
+    - cmake-data
     - libssl-dev
     - python-pip
 

CMakeLists.txt

@@ -1,21 +1,23 @@
-cmake_minimum_required(VERSION 2.6)
+cmake_minimum_required(VERSION 2.8)
 
 set(SOURCES address.c aescrypt.c aeskey.c aes_modes.c aestab.c base58.c bignum.c bip32.c bip39.c ecdsa.c hmac.c nist256p1.c pbkdf2.c rand.c ripemd160.c secp256k1.c sha2.c ed25519-donna/ed25519.c sha3.c)
-include_directories(ed25519-donna)
-include_directories(curve25519-donna)
+
+add_library(TrezorCrypto STATIC ${SOURCES})
+
+target_include_directories(TrezorCrypto PUBLIC .)
+target_include_directories(TrezorCrypto PUBLIC ed25519-donna)
+target_include_directories(TrezorCrypto PUBLIC curve25519-donna)
 
 # disable sequence point warnings where they are expected
 set_source_files_properties(aeskey.c PROPERTIES
                             COMPILE_FLAGS -Wno-sequence-point)
 
-set(CMAKE_C_FLAGS "-std=c99")
+target_compile_options(TrezorCrypto PRIVATE "-std=c99")
 
 if(MSVC)
   set_source_files_properties(${SOURCES} PROPERTIES LANGUAGE CXX)
 endif(MSVC)
 
-add_library(TrezorCrypto STATIC ${SOURCES})
-
 # Build trezor-crypto tests (requires OpenSSL)
 if (TREZOR_CRYPTO_TESTS)
     add_executable(tests tests.c)