Modernise FindReadline.cmake, and fix on Solaris

Author: NWilson

.github/workflows/build.yml

@@ -420,7 +420,7 @@ jobs:
             echo "== CMake, 64-bit =="
             cd ../build-cmake-64
 
-            CC="cc -m64" cmake $CMAKE_FLAGS -DNCURSES_LIBRARY=termcap -DPCRE2_BUILD_PCRE2_16=ON -DPCRE2_BUILD_PCRE2_32=ON -DBUILD_SHARED_LIBS=ON -DBUILD_STATIC_LIBS=ON -DPCRE2_DEBUG=ON -DCMAKE_C_FLAGS="$CFLAGS_SOLARIS_CC" -DCMAKE_COMPILE_WARNING_AS_ERROR=ON -DCMAKE_BUILD_TYPE=Release -B build
+            CC="cc -m64" cmake $CMAKE_FLAGS -DPCRE2_BUILD_PCRE2_16=ON -DPCRE2_BUILD_PCRE2_32=ON -DBUILD_SHARED_LIBS=ON -DBUILD_STATIC_LIBS=ON -DPCRE2_DEBUG=ON -DCMAKE_C_FLAGS="$CFLAGS_SOLARIS_CC" -DCMAKE_COMPILE_WARNING_AS_ERROR=ON -DCMAKE_BUILD_TYPE=Release -B build
             cd build
             make
             ctest -j3 --output-on-failure

CMakeLists.txt

@@ -161,6 +161,7 @@ include(CheckSymbolExists)
 include(CheckIncludeFile)
 include(CheckTypeSize)
 include(CMakePackageConfigHelpers)
+include(CMakePushCheckState)
 include(GNUInstallDirs) # for CMAKE_INSTALL_LIBDIR
 include(PCRE2CheckLinkerFlag)
 include(PCRE2UseSystemExtensions)
@@ -172,6 +173,10 @@ check_include_file(sys/types.h HAVE_SYS_TYPES_H)
 check_include_file(unistd.h HAVE_UNISTD_H)
 check_include_file(windows.h HAVE_WINDOWS_H)
 
+# Check whether any system-wide extensions need to be enabled, in order for
+# OS functionality to be exposed.
+pcre2_use_system_extensions()
+
 check_symbol_exists(memfd_create "sys/mman.h" HAVE_MEMFD_CREATE)
 check_symbol_exists(secure_getenv "stdlib.h" HAVE_SECURE_GETENV)
 
@@ -184,10 +189,10 @@ check_c_source_compiles(
   HAVE_REALPATH
 )
 
+cmake_push_check_state()
 if(NOT DEFINED CMAKE_REQUIRED_FLAGS)
   set(CMAKE_REQUIRED_FLAGS "")
 endif()
-set(ORIG_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
 if(NOT MSVC AND NOT CMAKE_C_COMPILER_ID STREQUAL "XL" AND NOT CMAKE_C_COMPILER_ID STREQUAL "SunPro")
   set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror")
 endif()
@@ -197,6 +202,7 @@ check_c_source_compiles(
   HAVE_ATTRIBUTE_UNINITIALIZED
 )
 
+# TODO Consider switching to modern "GenerateExportHeader"
 check_c_source_compiles(
   [=[
   extern __attribute__ ((visibility ("default"))) int f(void);
@@ -206,14 +212,14 @@ check_c_source_compiles(
   HAVE_VISIBILITY
 )
 
+cmake_pop_check_state()
+
 if(HAVE_VISIBILITY)
   set(PCRE2_EXPORT [=[__attribute__ ((visibility ("default")))]=])
 else()
   set(PCRE2_EXPORT)
 endif()
 
-set(CMAKE_REQUIRED_FLAGS ${ORIG_CMAKE_REQUIRED_FLAGS})
-
 check_c_source_compiles("int main(void) { __assume(1); return 0; }" HAVE_BUILTIN_ASSUME)
 
 check_c_source_compiles(
@@ -271,11 +277,6 @@ if(INTEL_CET_ENABLED)
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mshstk")
 endif()
 
-# Check whether any system-wide extensions need to be enabled, in order for
-# OS functionality to be exposed.
-
-pcre2_use_system_extensions()
-
 # User-configurable options
 #
 # Note: CMakeSetup displays these in alphabetical order, regardless of
@@ -537,19 +538,7 @@ if(PCRE2_SUPPORT_JIT)
 endif()
 
 if(PCRE2_SUPPORT_JIT_SEALLOC)
-  set(CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE)
-  check_symbol_exists(mkostemp stdlib.h REQUIRED)
-  unset(CMAKE_REQUIRED_DEFINITIONS)
-  if(${REQUIRED})
-    if(${CMAKE_SYSTEM_NAME} MATCHES Linux|NetBSD)
-      add_compile_definitions(_GNU_SOURCE)
-      set(SLJIT_PROT_EXECUTABLE_ALLOCATOR 1)
-    else()
-      message(FATAL_ERROR "Your configuration is not supported")
-    endif()
-  else()
-    set(PCRE2_SUPPORT_JIT_SEALLOC OFF)
-  endif()
+  set(SLJIT_PROT_EXECUTABLE_ALLOCATOR 1)
 endif()
 
 if(PCRE2GREP_SUPPORT_JIT)

cmake/FindEditline.cmake

@@ -1,13 +1,10 @@
 # Modified from FindReadline.cmake (PH Feb 2012)
 
-if(EDITLINE_INCLUDE_DIR AND EDITLINE_LIBRARY)
-  set(EDITLINE_FOUND TRUE)
-else()
-  find_path(EDITLINE_INCLUDE_DIR readline.h PATH_SUFFIXES editline edit/readline)
+find_path(EDITLINE_INCLUDE_DIR readline.h PATH_SUFFIXES editline edit/readline)
+mark_as_advanced(EDITLINE_INCLUDE_DIR)
 
-  find_library(EDITLINE_LIBRARY NAMES edit)
-  include(FindPackageHandleStandardArgs)
-  find_package_handle_standard_args(Editline DEFAULT_MSG EDITLINE_INCLUDE_DIR EDITLINE_LIBRARY)
+find_library(EDITLINE_LIBRARY NAMES edit)
+mark_as_advanced(EDITLINE_LIBRARY)
 
-  mark_as_advanced(EDITLINE_INCLUDE_DIR EDITLINE_LIBRARY)
-endif()
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(Editline DEFAULT_MSG EDITLINE_LIBRARY EDITLINE_INCLUDE_DIR)

cmake/FindReadline.cmake

@@ -3,25 +3,53 @@
 # --> BSD licensed
 #
 # GNU Readline library finder
-if(READLINE_INCLUDE_DIR AND READLINE_LIBRARY AND NCURSES_LIBRARY)
-  set(READLINE_FOUND TRUE)
-else()
-  find_path(READLINE_INCLUDE_DIR readline/readline.h /usr/include/readline)
-
-  # 2008-04-22 The next clause used to read like this:
-  #
-  #  FIND_LIBRARY(READLINE_LIBRARY NAMES readline)
-  #        FIND_LIBRARY(NCURSES_LIBRARY NAMES ncurses )
-  #        include(FindPackageHandleStandardArgs)
-  #        FIND_PACKAGE_HANDLE_STANDARD_ARGS(Readline DEFAULT_MSG NCURSES_LIBRARY READLINE_INCLUDE_DIR READLINE_LIBRARY )
-  #
-  # I was advised to modify it such that it will find an ncurses library if
-  # required, but not if one was explicitly given, that is, it allows the
-  # default to be overridden. PH
-
-  find_library(READLINE_LIBRARY NAMES readline)
-  include(FindPackageHandleStandardArgs)
-  find_package_handle_standard_args(Readline DEFAULT_MSG READLINE_INCLUDE_DIR READLINE_LIBRARY)
-
-  mark_as_advanced(READLINE_INCLUDE_DIR READLINE_LIBRARY)
+
+find_path(READLINE_INCLUDE_DIR readline/readline.h PATH_SUFFIXES include)
+mark_as_advanced(READLINE_INCLUDE_DIR)
+
+find_library(READLINE_LIBRARY NAMES readline)
+mark_as_advanced(READLINE_LIBRARY)
+
+if(READLINE_INCLUDE_DIR AND READLINE_LIBRARY)
+  # Check if we need to link to ncurses as well
+
+  include(CheckSymbolExists)
+  include(CMakePushCheckState)
+
+  cmake_push_check_state(RESET)
+  set(CMAKE_REQUIRED_LIBRARIES "${READLINE_LIBRARY}")
+  set(CMAKE_REQUIRED_INCLUDES "${READLINE_INCLUDE_DIR}")
+  check_symbol_exists("readline" "stdio.h;readline/readline.h" HAVE_READLINE_FUNC)
+
+  if(NOT HAVE_READLINE_FUNC)
+    foreach(
+      lib IN ITEMS
+      tinfo
+      curses
+      ncurses
+      ncursesw
+      termcap
+    )
+      find_library(NCURSES_LIBRARY_${lib} NAMES ${lib})
+      mark_as_advanced(NCURSES_LIBRARY_${lib})
+      if(NCURSES_LIBRARY_${lib})
+        cmake_reset_check_state()
+        set(CMAKE_REQUIRED_LIBRARIES "${READLINE_LIBRARY}" "${NCURSES_LIBRARY_${lib}}")
+        set(CMAKE_REQUIRED_INCLUDES "${READLINE_INCLUDE_DIR}")
+        check_symbol_exists("readline" "stdio.h;readline/readline.h" HAVE_READLINE_FUNC_${lib})
+
+        if(HAVE_READLINE_FUNC_${lib})
+          message(STATUS "Looking for readline - readline needs ${lib}")
+          set(NCURSES_LIBRARY "${NCURSES_LIBRARY_${lib}}" CACHE FILEPATH "Path to the ncurses library")
+          mark_as_advanced(NCURSES_LIBRARY)
+          break()
+        endif()
+      endif()
+    endforeach()
+  endif()
+
+  cmake_pop_check_state()
 endif()
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(Readline DEFAULT_MSG READLINE_LIBRARY READLINE_INCLUDE_DIR)

cmake/PCRE2UseSystemExtensions.cmake

@@ -10,18 +10,23 @@
 # So far, we know that we require:
 #   - _ALL_SOURCE on IBM systems (z/OS, probably AIX) in order to call
 #     getrlimit() in pcre2test.
+#   - _GNU_SOURCE on Linux in order to call mkostemp() in some (non-default)
+#     configurations of the JIT.
 #
 # Autoconf enables this unconditionally. However, our CMake script potentially
 # supports *more* platforms than Autoconf, so we use a feature check.
 
 function(pcre2_use_system_extensions)
-  if (WIN32)
+  if(WIN32)
     return()
   endif()
 
   include(CheckCSourceCompiles)
+  include(CMakePushCheckState)
 
-  set(_pcre2_test_src "
+  set(
+    _pcre2_test_src
+    "
 #include <sys/time.h>
 #include <sys/resource.h>
 
@@ -30,18 +35,34 @@ int main(void) {
     getrlimit(RLIMIT_STACK, &rlim);
     return 0;
 }
-")
+"
+  )
 
   check_c_source_compiles("${_pcre2_test_src}" HAVE_GETRLIMIT)
 
-  if (NOT HAVE_GETRLIMIT)
+  if(NOT HAVE_GETRLIMIT)
     # Try again with _ALL_SOURCE
+    cmake_push_check_state(RESET)
     set(CMAKE_REQUIRED_DEFINITIONS "-D_ALL_SOURCE")
     check_c_source_compiles("${_pcre2_test_src}" HAVE_GETRLIMIT_ALLSOURCE)
-    unset(CMAKE_REQUIRED_DEFINITIONS)
+    cmake_pop_check_state()
 
-    if (HAVE_GETRLIMIT_ALLSOURCE)
+    if(HAVE_GETRLIMIT_ALLSOURCE)
       add_compile_definitions(_ALL_SOURCE)
     endif()
   endif()
+
+  check_symbol_exists(mkostemp stdlib.h HAVE_MKOSTEMP)
+
+  if(NOT HAVE_MKOSTEMP)
+    # Try again with _GNU_SOURCE
+    cmake_push_check_state(RESET)
+    set(CMAKE_REQUIRED_DEFINITIONS "-D_GNU_SOURCE")
+    check_symbol_exists(mkostemp stdlib.h HAVE_MKOSTEMP_GNUSOURCE)
+    cmake_pop_check_state()
+
+    if(HAVE_MKOSTEMP_GNUSOURCE)
+      add_compile_definitions(_GNU_SOURCE)
+    endif()
+  endif()
 endfunction()

configure.ac

@@ -677,7 +677,7 @@ AC_LINK_IFELSE([AC_LANG_PROGRAM([[
 AC_MSG_RESULT([no]))
 LIBS="$OLD_LIBS"
 
-# Check for the availabiity of libreadline
+# Check for the availability of libreadline
 
 if test "$enable_pcre2test_libreadline" = "yes"; then
  AC_CHECK_HEADERS([readline/readline.h], [HAVE_READLINE_H=1])