add USE_READLINE cmake flag

CMakeLists.txt

@@ -27,6 +27,7 @@ option(USE_DOXYGEN "Build HTML cross reference with doxygen" OFF)
 option(USE_PANDOC "Build man pages and HTML reference with pandoc" ON)
 option(USE_POC "Build small, uninstalled proof-of-concept binaries" ON)
 option(USE_QRCODEGEN "Enable libqrcodegen QR code support" OFF)
+option(USE_READLINE "Enable libreadline line-editing support" ON)
 option(USE_STATIC "Build static libraries (in addition to shared)" ON)
 set(USE_MULTIMEDIA "ffmpeg" CACHE STRING "Multimedia engine, one of 'ffmpeg', 'oiio', or 'none'")
 set_property(CACHE USE_MULTIMEDIA PROPERTY STRINGS ffmpeg oiio none)
@@ -85,9 +86,11 @@ pkg_search_module(TERMINFO REQUIRED tinfo>=6.1 ncursesw>=6.1)
 set_property(GLOBAL APPEND PROPERTY PACKAGES_FOUND terminfo)
 set_package_properties(terminfo PROPERTIES TYPE REQUIRED)
 set(PKGCONF_REQ_PRIV "${TERMINFO_LIBRARIES}")
+if(${USE_READLINE})
 pkg_search_module(READLINE REQUIRED readline>=8.0)
 set_property(GLOBAL APPEND PROPERTY PACKAGES_FOUND readline)
 set_package_properties(readline PROPERTIES TYPE REQUIRED)
+endif()
 if(${USE_FFMPEG})
 pkg_check_modules(AVCODEC REQUIRED libavcodec>=57.0)
 pkg_check_modules(AVFORMAT REQUIRED libavformat>=57.0)
@@ -157,7 +160,6 @@ target_include_directories(notcurses-core
     "${CMAKE_REQUIRED_INCLUDES}"
     "${PROJECT_BINARY_DIR}/include"
     "${TERMINFO_INCLUDE_DIRS}"
-    "${READLINE_INCLUDE_DIRS}"
 )
 target_include_directories(notcurses-core-static
   PRIVATE
@@ -166,12 +168,10 @@ target_include_directories(notcurses-core-static
     "${CMAKE_REQUIRED_INCLUDES}"
     "${PROJECT_BINARY_DIR}/include"
     "${TERMINFO_STATIC_INCLUDE_DIRS}"
-    "${READLINE_STATIC_INCLUDE_DIRS}"
 )
 target_link_libraries(notcurses-core
   PRIVATE
     "${TERMINFO_LIBRARIES}"
-    "${READLINE_LIBRARIES}"
     "${LIBM}"
     "${LIBRT}"
     "${unistring}"
@@ -181,7 +181,6 @@ target_link_libraries(notcurses-core
 target_link_libraries(notcurses-core-static
   PRIVATE
     "${TERMINFO_STATIC_LIBRARIES}"
-    "${READLINE_STATIC_LIBRARIES}"
     "${LIBM}"
     "${LIBRT}"
     "${unistring}"
@@ -191,12 +190,10 @@ target_link_libraries(notcurses-core-static
 target_link_directories(notcurses-core
   PRIVATE
     "${TERMINFO_LIBRARY_DIRS}"
-    "${READLINE_LIBRARY_DIRS}"
 )
 target_link_directories(notcurses-core-static
   PRIVATE
     "${TERMINFO_STATIC_LIBRARY_DIRS}"
-    "${READLINE_STATIC_LIBRARY_DIRS}"
 )
 # don't want these on freebsd/dragonfly/osx
 if(${CMAKE_SYSTEM_NAME} STREQUAL "Linux")

README.md

@@ -109,7 +109,7 @@ may well be possible to use still older versions. Let me know of any successes!
 * (OPTIONAL) (OpenImageIO, testing, C++ bindings): A C++17 compiler
 * (build+runtime) From [NCURSES](https://invisible-island.net/ncurses/announce.html): terminfo 6.1+
 * (build+runtime) GNU [libunistring](https://www.gnu.org/software/libunistring/) 0.9.10+
-* (build+runtime) GNU [Readline](https://www.gnu.org/software/readline/) 8.0+
+* (OPTIONAL) (build+runtime) GNU [Readline](https://www.gnu.org/software/readline/) 8.0+
 * (OPTIONAL) (build+runtime) From QR-Code-generator: [libqrcodegen](https://github.com/nayuki/QR-Code-generator) 1.5.0+
 * (OPTIONAL) (build+runtime) From [FFmpeg](https://www.ffmpeg.org/): libswscale 5.0+, libavformat 57.0+, libavutil 56.0+
 * (OPTIONAL) (build+runtime) [OpenImageIO](https://github.com/OpenImageIO/oiio) 2.15.0+, requires C++

src/lib/direct.c

@@ -4,7 +4,9 @@
 #include <string.h>
 #include <unistd.h>
 #include <termios.h>
+#ifdef USE_READLINE
 #include <readline/readline.h>
+#endif
 #include "version.h"
 #include "visual-details.h"
 #include "notcurses/direct.h"
@@ -759,7 +761,9 @@ ncdirect_stop_minimal(void* vnc){
   ncdirect* nc = vnc;
   int ret = drop_signals(nc);
   if(nc->initialized_readline){
+#ifdef USE_READLINE
     rl_deprep_terminal();
+#endif
   }
   ret |= reset_term_attributes(&nc->tcache, nc->ttyfp);
   if(nc->ctermfd >= 0){
@@ -854,6 +858,7 @@ int ncdirect_stop(ncdirect* nc){
 }
 
 char* ncdirect_readline(ncdirect* n, const char* prompt){
+#ifdef USE_READLINE
   if(!n->initialized_readline){
     rl_outstream = n->ttyfp;
     rl_instream = stdin;
@@ -861,6 +866,11 @@ char* ncdirect_readline(ncdirect* n, const char* prompt){
     n->initialized_readline = true;
   }
   return readline(prompt);
+#else
+  (void)n;
+  (void)prompt;
+  return NULL;
+#endif
 }
 
 static inline int

tools/builddef.h.in

@@ -1,6 +1,7 @@
 // Populated by CMake; not installed
 #cmakedefine DFSG_BUILD
 #cmakedefine USE_QRCODEGEN
+#cmakedefine USE_READLINE
 // exclusive with USE_OIIO
 #cmakedefine USE_FFMPEG
 // exclusive with USE_FFMPEG