Removed the thirdparty 'unrar' library because it is incompatible wit…

…h the base license of that library, GPLv2.

Support for rar archives was not implemented, so no functionality was affected.
For future implementation of support for rar archives, need to use an external program `unrar` or `rar`.
See https://www.gnu.org/licenses/gpl-faq.html#GPLPlugins

CMakeLists.txt

@@ -156,21 +156,9 @@ endif( ${GUI} STREQUAL QT5 )
 # thirdparty sources definitions
 include("${CMAKE_SOURCE_DIR}/thirdparty_repo/repo_srcdirs.cmake")
 
-#UNRAR support
+#UNRAR support (not implemented yet)
 if(DEFINED USE_UNRAR)
-  message("Will build static UNRAR library")
-  SET(USE_UNRAR 1)
-  SET(UNRAR_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/thirdparty_unman/unrar)
-  SET(UNRAR_LIBRARIES unrar)
   ADD_DEFINITIONS(-DUSE_UNRAR=1)
-  INCLUDE_DIRECTORIES(${UNRAR_INCLUDE_DIR})
-  ADD_SUBDIRECTORY(thirdparty_unman/unrar)
-else()
-  message("NO_UNRAR parameter specified: Will not support UNRAR")
-  SET(UNRAR_INCLUDE_DIR)
-  SET(UNRAR_LIBRARIES)
-  ADD_DEFINITIONS(-DUSE_UNRAR=0)
-  SET(USE_UNRAR 0)
 endif(DEFINED USE_UNRAR)
 
 find_path(NANOSVG_INCLUDE_DIR nanosvg.h DOC "Path to NanoSVG include dir")

cr3qt/CMakeLists.txt

@@ -174,7 +174,7 @@ IF(MAC)
 ELSE()
     SET (EXTRA_LIBS ${STD_LIBS} ${QT_LIBRARIES} ${Qt5Core_LIBRARIES} ${Qt5Widgets_LIBRARIES} )
 ENDIF(MAC)
-TARGET_LINK_LIBRARIES(cr3 crengine tinydict ${UNRAR_LIBRARIES} ${EXTRA_LIBS})
+TARGET_LINK_LIBRARIES(cr3 crengine tinydict ${EXTRA_LIBS})
 
 IF (MAC)
 

crengine/src/lvstream/lvrararc.cpp

@@ -1,7 +1,7 @@
 /***************************************************************************
  *   CoolReader engine                                                     *
  *   Copyright (C) 2008,2011 Vadim Lopatin <[email protected]>      *
- *   Copyright (C) 2020 Aleksey Chernov <[email protected]>               *
+ *   Copyright (C) 2020,2022 Aleksey Chernov <[email protected]>          *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or         *
  *   modify it under the terms of the GNU General Public License           *
@@ -19,6 +19,18 @@
  *   MA 02110-1301, USA.                                                   *
  ***************************************************************************/
 
+/**
+ * Support for rar archives is not implemented yet.
+ * When implementing support for rar archives, we cannot use 'unrar'
+ * library, we cannot link the program with it, since it has a license
+ * that is not compatible with the GPL.
+ * Instead, we can call the 'unrar' or 'rar' program installed on the
+ * system and process the data it returns.
+ * After support for rar archives is implemented, this comment should be removed.
+ * 
+ * See https://www.gnu.org/licenses/gpl-faq.html#GPLPlugins
+ */
+
 #include "lvrararc.h"
 
 #if (USE_UNRAR==1)