Test under Linux and OSX, with gcc and clang

Possibly link the rt library for clock_gettime()

.travis.yml

@@ -1,7 +1,20 @@
+sudo: false
+
 language: c
 
+os:
+    - linux
+    - osx
+
+compiler:
+    - clang
+    - gcc
+
 before_script:
+    - export PKG_CONFIG_PATH=/tmp/lib/pkgconfig
+    - git clone https://github.com/jedisct1/libsodium.git --branch=stable
+    - cd libsodium && ./autogen.sh && ./configure --enable-minimal --disable-dependency-tracking --prefix=/tmp && make install && cd -
     - ./autogen.sh    
 
 script:
-    - ./configure && make
+    - ./configure --disable-dependency-tracking && make distcheck

configure.ac

@@ -15,7 +15,10 @@ AC_TYPE_SSIZE_T
 AC_TYPE_UINT8_T
 AC_TYPE_INT64_T
 AC_FUNC_MALLOC
-AC_CHECK_FUNCS([clock_gettime socket strtol])
-PKG_CHECK_MODULES([libsodium], [libsodium >= 1.0.4])
+AC_CHECK_FUNCS([socket strtol])
+AC_SEARCH_LIBS(clock_gettime, [rt],
+  [AC_DEFINE(HAVE_CLOCK_GETTIME,[1],[define if you have clock_gettime()])])
+PKG_CHECK_MODULES([libsodium], [libsodium >= 1.0.4],
+  [CFLAGS="$CFLAGS $libsodium_CFLAGS"], [echo "not found"])
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT