From 48b1583830c11e5866422d4df82911029090f31e Mon Sep 17 00:00:00 2001
From: Markus Makela <markus.makela@mariadb.com>
Date: Sun, 9 Oct 2016 13:20:31 +0300
Subject: [PATCH] Add FindJansson.cmake

Added find_package module for CMake which locates the Jansson libraries
and headers. This will make dependency checking easier and prevents build
failures due to missing dependencies.
---
 CMakeLists.txt                             |  1 +
 avro/CMakeLists.txt                        |  2 +-
 cmake/FindJansson.cmake                    | 16 ++++++++++++++++
 server/modules/filter/cache/CMakeLists.txt | 20 ++++++++++++--------
 server/modules/routing/avro/CMakeLists.txt |  7 ++++---
 5 files changed, 34 insertions(+), 12 deletions(-)
 create mode 100644 cmake/FindJansson.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6f5e3f833..2ed799c0d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -41,6 +41,7 @@ find_package(Git)
 find_package(CURL)
 find_package(RabbitMQ)
 find_package(LibUUID)
+find_package(Jansson)
 find_package(Avro)
 find_package(GSSAPI)
 
diff --git a/avro/CMakeLists.txt b/avro/CMakeLists.txt
index 1e86df41d..cb6df2eed 100644
--- a/avro/CMakeLists.txt
+++ b/avro/CMakeLists.txt
@@ -1,4 +1,4 @@
-if (AVRO_FOUND)
+if (AVRO_FOUND AND JANSSON_FOUND)
   include_directories(${CMAKE_CURRENT_SOURCE_DIR})
   add_library(maxavro maxavro.c maxavro_schema.c maxavro_record.c maxavro_file.c)
   target_link_libraries(maxavro maxscale-common jansson)
diff --git a/cmake/FindJansson.cmake b/cmake/FindJansson.cmake
new file mode 100644
index 000000000..c0322975e
--- /dev/null
+++ b/cmake/FindJansson.cmake
@@ -0,0 +1,16 @@
+# This CMake file locates the Jansson libraries and headers
+#
+# The following variables are set:
+# JANSSON_FOUND - If the Avro C library was found
+# JANSSON_LIBRARIES - Path to the static library
+# JANSSON_INCLUDE_DIR - Path to Avro headers
+
+find_path(JANSSON_INCLUDE_DIR jansson.h)
+find_library(JANSSON_LIBRARIES NAMES libjansson.a libjansson.so)
+
+if (JANSSON_INCLUDE_DIR AND JANSSON_LIBRARIES)
+  message(STATUS "Found Jansson: ${JANSSON_LIBRARIES}")
+  set(JANSSON_FOUND TRUE)
+else()
+  message(STATUS "Could not find Jansson")
+endif()
diff --git a/server/modules/filter/cache/CMakeLists.txt b/server/modules/filter/cache/CMakeLists.txt
index 89db9c15b..3977cfbb0 100644
--- a/server/modules/filter/cache/CMakeLists.txt
+++ b/server/modules/filter/cache/CMakeLists.txt
@@ -1,11 +1,15 @@
-add_library(cache SHARED cache.c rules.c storage.c)
-target_link_libraries(cache maxscale-common jansson)
-set_target_properties(cache PROPERTIES VERSION "1.0.0")
-set_target_properties(cache PROPERTIES LINK_FLAGS -Wl,-z,defs)
-install_module(cache experimental)
+if (JANSSON_FOUND)
+  add_library(cache SHARED cache.c rules.c storage.c)
+  target_link_libraries(cache maxscale-common jansson)
+  set_target_properties(cache PROPERTIES VERSION "1.0.0")
+  set_target_properties(cache PROPERTIES LINK_FLAGS -Wl,-z,defs)
+  install_module(cache experimental)
 
-add_subdirectory(storage)
+  add_subdirectory(storage)
 
-if(BUILD_TESTS)
-  add_subdirectory(test)
+  if(BUILD_TESTS)
+    add_subdirectory(test)
+  endif()
+else()
+  message(STATUS "No Jansson libraries found, not building cache filter.")
 endif()
diff --git a/server/modules/routing/avro/CMakeLists.txt b/server/modules/routing/avro/CMakeLists.txt
index 4fcb896b6..0fed40b78 100644
--- a/server/modules/routing/avro/CMakeLists.txt
+++ b/server/modules/routing/avro/CMakeLists.txt
@@ -1,10 +1,11 @@
-if(AVRO_FOUND)
+if(AVRO_FOUND AND JANSSON_FOUND)
   include_directories(${AVRO_INCLUDE_DIR})
+  include_directories(${JANSSON_INCLUDE_DIR})
   add_library(avrorouter SHARED avro.c ../binlog/binlog_common.c avro_client.c avro_schema.c avro_rbr.c avro_file.c avro_index.c)
   set_target_properties(avrorouter PROPERTIES VERSION "1.0.0")
   set_target_properties(avrorouter PROPERTIES LINK_FLAGS -Wl,-z,defs)
-  target_link_libraries(avrorouter maxscale-common jansson ${AVRO_LIBRARIES} maxavro sqlite3 lzma)
+  target_link_libraries(avrorouter maxscale-common ${JANSSON_LIBRARIES} ${AVRO_LIBRARIES} maxavro sqlite3 lzma)
   install_module(avrorouter core)
 else()
-  message(STATUS "Avro C libraries were not found, avrorouter will not be built.")
+  message(STATUS "No Avro C or Jansson libraries found, not building avrorouter.")
 endif()