Add jansson library to libckpool requirements

configure.ac

@@ -31,12 +31,16 @@ AC_FUNC_ALLOCA
 
 PKG_PROG_PKG_CONFIG()
 
+AC_CHECK_LIB(jansson, json_loads, ,
+	AC_MSG_ERROR([Could not find jansson library - please install libjansson-dev]))
+
 AC_CHECK_HEADERS(stdio.h stdlib.h fcntl.h sys/time.h unistd.h)
 AC_CHECK_HEADERS(ctype.h errno.h byteswap.h string.h time.h)
 AC_CHECK_HEADERS(endian.h sys/endian.h arpa/inet.h syslog.h)
 AC_CHECK_HEADERS(alloca.h pthread.h stdio.h math.h)
 AC_CHECK_HEADERS(sys/types.h sys/socket.h netdb.h)
 AC_CHECK_HEADERS(stdint.h netinet/in.h netinet/tcp.h)
+AC_CHECK_HEADERS(jansson.h)
 
 PTHREAD_LIBS="-lpthread"
 MATH_LIBS="-lm"

src/Makefile.am

@@ -2,7 +2,7 @@ ACLOCAL_AMFLAGS = -I m4
 
 lib_LTLIBRARIES = libckpool.la
 libckpool_la_SOURCES = libckpool.c
-libckpool_la_LIBADD = @MATH_LIBS@ @PTHREAD_LIBS@
+libckpool_la_LIBADD = @MATH_LIBS@ @PTHREAD_LIBS@ @JANSSON_LIBS@
 
 bin_PROGRAMS = ckpool
 ckpool_SOURCES = ckpool.c