* ext/curses/extconf.rb: try to distinguish curses_version is a

  function or variable.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@34745 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 46 insertions, 1 deletions

diff --git a/ext/curses/curses.c b/ext/curses/curses.c
index eec364ba15..60ba65b15b 100644
--- a/ext/curses/curses.c
+++ b/ext/curses/curses.c
@@ -2768,8 +2768,14 @@ Init_curses(void)
     rb_define_module_function(mCurses, "def_prog_mode", curses_def_prog_mode, 0);
     rb_define_module_function(mCurses, "reset_prog_mode", curses_reset_prog_mode, 0);
 
-#ifdef NCURSES_VERSION
+#ifdef HAVE_FUNC_CURSES_VERSION
     rb_define_const(mCurses, "VERSION", rb_str_new2(curses_version()));
+#elif HAVE_VAR_CURSES_VERSION
+    {
+        /* SVR4 curses has an undocumented and undeclared variable, curses_version. */
+        RUBY_EXTERN char *curses_version;
+        rb_define_const(mCurses, "VERSION", rb_sprintf("curses (%s)", curses_version));
+    }
 #else
     rb_define_const(mCurses, "VERSION", rb_str_new2("unknown"));
 #endif
diff --git a/ext/curses/extconf.rb b/ext/curses/extconf.rb
index e1499437d0..14dfa7d5cb 100644
--- a/ext/curses/extconf.rb
+++ b/ext/curses/extconf.rb
@@ -72,5 +72,44 @@ if header_library
   have_var("TABSIZE", curses)
   have_var("COLORS", curses)
   have_var("COLOR_PAIRS", curses)
+
+  # SVR4 curses has a (undocumented) variable char *curses_version.
+  # ncurses and PDcurses has a function char *curses_version().
+  # Note that the original BSD curses doesn't provide version information.
+
+  prolog = cpp_include(curses)
+  if checking_for(checking_message('function curses_version', curses)) {
+      try_run(<<-"End")
+        #{prolog}
+        int main(int argc, char *argv[])
+        {
+            curses_version();
+            return EXIT_SUCCESS;
+        }
+      End
+    }
+    $defs << '-DHAVE_FUNC_CURSES_VERSION'
+  end
+
+  if checking_for(checking_message('variable curses_version', curses)) {
+      try_run(<<-"End")
+        #{prolog}
+        extern char *curses_version;
+        int main(int argc, char *argv[])
+        {
+            int i = 0;
+            for (i = 0; i < 100; i++) {
+                if (curses_version[i] == 0)
+                    return 0 < i ? EXIT_SUCCESS : EXIT_FAILURE;
+                if (curses_version[i] & 0x80)
+                    return EXIT_FAILURE;
+            }
+            return EXIT_FAILURE;
+        }
+      End
+    }
+    $defs << '-DHAVE_VAR_CURSES_VERSION'
+  end
+
   create_makefile("curses")
 end