cmake: fix libfbclient discovery if fb_config is not present

Signed-off-by: Alexander Golubev <fatzer2@gmail.com>

ConfigureChecks.cmake

@@ -424,39 +424,52 @@ endif()
 
 if( (BUILD_SQL_PLUGIN_IBASE OR (WITH_MODULE_SQL AND WITH_SQL_DRIVER_IBASE)) AND NOT FBCLIENT_FOUND )
     find_program( FIREBIRD_CONFIG fb_config )
-    if( NOT FIREBIRD_CONFIG )
-        tde_message_fatal( "IBASE support has been requested, but was not found on your system" )
-     else()
+    if( FIREBIRD_CONFIG )
         macro( _fbclient_config  __type __var )
-        execute_process(
-            COMMAND ${FIREBIRD_CONFIG} --${__type}
-            OUTPUT_VARIABLE ${__var}
-            RESULT_VARIABLE __result
-            OUTPUT_STRIP_TRAILING_WHITESPACE
-        )
-        if( _result )
-            tde_message_fatal( "Unable to run ${FIREBIRD_CONFIG}!" )
-        endif()
+            if (NOT DEFINED ${__var})
+                execute_process(
+                    COMMAND ${FIREBIRD_CONFIG} --${__type}
+                    OUTPUT_VARIABLE ${__var}
+                    RESULT_VARIABLE __result
+                    OUTPUT_STRIP_TRAILING_WHITESPACE
+                )
+                if( _result )
+                    tde_message_fatal( "Unable to run ${FIREBIRD_CONFIG}!" )
+                endif()
+                string( REGEX REPLACE "(^| +)-." ";" ${__var} "${${__var}}" )
+            endif()
         endmacro()
 
         _fbclient_config( cflags FBCLIENT_INCLUDE_DIRS )
         _fbclient_config( libs   FBCLIENT_LIBRARIES    )
 
-        if( FBCLIENT_INCLUDE_DIRS )
-            string( REGEX REPLACE "(^| +)-I" ";" FBCLIENT_INCLUDE_DIRS "${FBCLIENT_INCLUDE_DIRS}" )
+        set( FBCLIENT_FOUND "ON" CACHE INTERNAL "" )
+     else( )
+        if( NOT FBCLIENT_LIBRARIES )
+            set( FBCLIENT_LIBRARIES "fbclient" )
         endif()
 
-        if( FBCLIENT_LIBRARIES )
-            string( REGEX REPLACE "(^| +)-l" ";" FBCLIENT_LIBRARIES "${FBCLIENT_LIBRARIES}" )
-        endif()
+        tde_save_and_set( CMAKE_REQUIRED_INCLUDES  "${FBCLIENT_INCLUDE_DIRS}" )
+        tde_save_and_set( CMAKE_REQUIRED_LIBRARIES "${FBCLIENT_LIBRARIES}" )
+        check_c_source_compiles("#include <ibase.h>
+            int main(){void(*p)(void)=(void(*)(void))*isc_attach_database;}"
+            FBCLIENT_FOUND )
+        tde_restore( CMAKE_REQUIRED_INCLUDES )
+        tde_restore( CMAKE_REQUIRED_LIBRARIES )
+
+    endif( FIREBIRD_CONFIG )
+
+    message( STATUS "FIREBIRD includes  ${FBCLIENT_INCLUDE_DIRS}")
+    message( STATUS "FIREBIRD libraries ${FBCLIENT_LIBRARIES}")
 
-        set( FBCLIENT_INCLUDE_DIRS "${FBCLIENT_INCLUDE_DIRS}" CACHE INTERNAL "" FORCE )
-        set( FBCLIENT_LIBRARIES "${FBCLIENT_LIBRARIES}" CACHE INTERNAL "" FORCE )
-        set( FBCLIENT_FOUND 1 CACHE INTERNAL "" FORCE )
+    set( FBCLIENT_INCLUDE_DIRS "${FBCLIENT_INCLUDE_DIRS}" CACHE INTERNAL "" )
+    set( FBCLIENT_LIBRARIES "${FBCLIENT_LIBRARIES}" CACHE INTERNAL "" )
 
-        message( STATUS "FIREBIRD includes  ${FBCLIENT_INCLUDE_DIRS} ")
-        message( STATUS "FIREBIRD libraries ${FBCLIENT_LIBRARIES} ")
-    endif( NOT FIREBIRD_CONFIG )
+    if( FBCLIENT_FOUND )
+        set( SQL_IBASE QT_SQL_IBASE )
+     else()
+        tde_message_fatal( "IBASE support has been requested, but was not found on your system" )
+    endif()
 endif()
 
 if( (BUILD_SQL_PLUGIN_SQLITE OR (WITH_MODULE_SQL AND WITH_SQL_DRIVER_SQLITE)) AND NOT SQLITE_FOUND )