Conditional compilation for Ruby 1.8.x and 1.9.x

Detect the Ruby version in extconf.rb using the RUBY_VERSION
constant and pass this along as a C preprocessor macro (either
RUBY_1_8_x or RUBY_1_9_x).

By definition we're doing this conditional compilation because
we want to manipulate RString struct members directly, so we
tie the conditional compilation very tightly to the version
number. Older or newer versions will bail with an error.

Signed-off-by: Wincent Colaiuta <win@wincent.com>

diff --git a/ext/extconf.rb b/ext/extconf.rb
index bfc8021cff1b10f56ad18b8a6847259fcf9c0f3a..f49c9c448a1f4978503b9cb0e0c47dc9dcf7f210 100644 (file)
--- a/ext/extconf.rb
+++ b/ext/extconf.rb
@@ -28,5 +28,14 @@ def missing item
   exit 1
 end
 
+case RUBY_VERSION
+when /\A1\.8/
+  $CFLAGS += ' -DRUBY_1_8_x'
+when /\A1\.9/
+  $CFLAGS += ' -DRUBY_1_9_x'
+else
+  raise "unsupported Ruby version: #{RUBY_VERSION}"
+end
+
 have_header('ruby.h') or missing 'ruby.h'
 create_makefile('wikitext')

diff --git a/ext/parser.c b/ext/parser.c
index a38f678c757e26c668d448380f356fb037dfc2e6..dfab24e66cbb8695d178c8aa3c27a5575c51b735 100644 (file)
--- a/ext/parser.c
+++ b/ext/parser.c
@@ -2591,21 +2591,14 @@ return_output:
     // nasty hack to avoid re-allocating our return value
     str_append(parser->output, null_str, 1); // null-terminate
     len = parser->output->len - 1; // don't count null termination
-#ifndef RUBY_VERSION
-#error RUBY_VERSION not defined
-#else
 
-// unfortunately this version check doesn't work properly in 1.9
-// (version.h not installed with 1.9, so likely other sytem-installed version.h gets picked up)
-#if RUBY_VERSION_MAJOR == 1 && RUBY_VERSION_MINOR == 9
-    // Ruby 1.9.x
+#if defined(RUBY_1_9_x)
     VALUE out = rb_str_buf_new(RSTRING_EMBED_LEN_MAX + 1);
     free(RSTRING_PTR(out));
     RSTRING(out)->as.heap.aux.capa = len;
     RSTRING(out)->as.heap.ptr = parser->output->ptr;
     RSTRING(out)->as.heap.len = len;
-#elif RUBY_VERSION_MAJOR == 1 && RUBY_VERSION_MINOR == 8
-    // Ruby 1.8.x
+#elif defined(RUBY_1_8_x)
     VALUE out = rb_str_new2("");
     free(RSTRING_PTR(out));
     RSTRING(out)->len = len;
@@ -2613,7 +2606,6 @@ return_output:
     RSTRING(out)->ptr = parser->output->ptr;
 #else
 #error unsupported RUBY_VERSION
-#endif
 #endif
     parser->output->ptr = NULL; // don't double-free
     return out;