Add DL.win32_last_error and DL.last_error.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@4922 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 69 insertions, 2 deletions

diff --git a/ext/dl/extconf.rb b/ext/dl/extconf.rb
index e712134448..beb15ab04c 100644
--- a/ext/dl/extconf.rb
+++ b/ext/dl/extconf.rb
@@ -127,6 +127,13 @@ if( $with_type_voidp )
   $dlconfig_h << "#define WITH_TYPE_VOIDP\n"
 end
 
+if( have_header("windows.h") )
+  have_library("kernel32")
+  have_func("GetLastError", "windows.h")
+  dlc_define("HAVE_WINDOWS_H")
+  have_windows_h = true
+end
+
 if( have_header("dlfcn.h") )
   dlc_define("HAVE_DLFCN_H")
   have_library("dl")
@@ -136,8 +143,7 @@ if( have_header("dlfcn.h") )
   if( have_func("dlerror") )
     dlc_define("HAVE_DLERROR")
   end
-elsif( have_header("windows.h") )
-  dlc_define("HAVE_WINDOWS_H")
+elsif ( have_windows_h )
   have_func("LoadLibrary")
   have_func("FreeLibrary")
   have_func("GetProcAddress")
diff --git a/ext/dl/sym.c b/ext/dl/sym.c
index 4a2d736465..dc48f6ce95 100644
--- a/ext/dl/sym.c
+++ b/ext/dl/sym.c
@@ -3,6 +3,7 @@
  */
 
 #include <ruby.h>
+#include <errno.h>
 #include "dl.h"
 
 VALUE rb_cDLSymbol;
@@ -316,6 +317,41 @@ stack_size(struct sym_data *sym)
   return size;
 }
 
+static ID rb_dl_id_DLErrno;
+
+static VALUE
+rb_dl_get_last_error(VALUE self)
+{
+  return rb_thread_local_aref(rb_thread_current(), rb_dl_id_DLErrno);
+}
+
+static VALUE
+rb_dl_set_last_error(VALUE self, VALUE val)
+{
+  errno = NUM2INT(val);
+  rb_thread_local_aset(rb_thread_current(), rb_dl_id_DLErrno, val);
+  return Qnil;
+}
+
+#ifdef HAVE_WINDOWS_H
+#include <windows.h>
+static ID rb_dl_id_DLW32Error;
+
+static VALUE
+rb_dl_win32_get_lasterror(VALUE self)
+{
+  return rb_thread_local_aref(rb_thread_current(), rb_dl_id_DLW32Error);
+}
+
+static VALUE
+rb_dl_win32_set_lasterror(VALUE self, VALUE val)
+{
+    SetLastError(NUM2INT(val));
+    rb_thread_local_aset(rb_thread_current(), rb_dl_id_DLW32Error, val);
+    return Qnil;
+}
+#endif
+
 VALUE
 rb_dlsym_call(int argc, VALUE argv[], VALUE self)
 {
@@ -675,6 +711,22 @@ rb_dlsym_call(int argc, VALUE argv[], VALUE self)
       rb_raise(rb_eDLTypeError, "unknown type `%c'", sym->type[0]);
     }
   }
+
+  {
+    /*
+     * We should get the value of errno/GetLastError() before calling another functions.
+     */
+    int last_errno = errno;
+#ifdef _WIN32
+    DWORD win32_last_err = GetLastError();
+#endif
+
+    rb_thread_local_aset(rb_thread_current(), rb_dl_id_DLErrno, INT2NUM(last_errno));
+#ifdef _WIN32
+    rb_thread_local_aset(rb_thread_current(), rb_dl_id_DLW32Error, INT2NUM(win32_last_err));
+#endif
+  }
+
   }
 #else /* defined(DLSTACK) */
   switch(ftype){
@@ -835,4 +887,13 @@ Init_dlsym()
   rb_define_method(rb_cDLSymbol, "to_s", rb_dlsym_cproto, 0);
   rb_define_method(rb_cDLSymbol, "to_ptr", rb_dlsym_to_ptr, 0);
   rb_define_method(rb_cDLSymbol, "to_i", rb_dlsym_to_i, 0);
+
+  rb_dl_id_DLErrno = rb_intern("DLErrno");
+  rb_define_singleton_method(rb_mDL, "last_error", rb_dl_get_last_error, 0);  
+  rb_define_singleton_method(rb_mDL, "last_error=", rb_dl_set_last_error, 1);
+#ifdef _WIN32
+  rb_dl_id_DLW32Error = rb_intern("DLW32Error");
+  rb_define_singleton_method(rb_mDL, "win32_last_error", rb_dl_win32_get_last_error, 0);
+  rb_define_singleton_method(rb_mDL, "win32_last_error=", rb_dl_win32_set_last_error, 1);
+#endif
 }