[libgdamm] SqlBuilder: Don't pass empty strings to the C functions.

[Murray Cumming <murrayc src gnome org>]

commit e2eb3ae7672a67519788e21921c4406b1cd85b25
Author: Murray Cumming <murrayc murrayc com>
Date:   Mon May 17 16:24:51 2010 +0200

    SqlBuilder: Don't pass empty strings to the C functions.
    
    * libgda/src/sqlbuilder.hg: Make sure that generated methods pass NULL
        for empty strings, because libgda does not always check that strings are
        not empty, though I try to fix that in libgda when I see it.

 ChangeLog                    |   12 ++++++++++--
 libgda/src/sqlbuilder.hg     |    2 ++
 tools/m4/convert_libgdamm.m4 |    1 -
 3 files changed, 12 insertions(+), 3 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 98dc68f..78f02f3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,8 +1,16 @@
+2010-05-17  Murray Cumming  <murrayc murrayc com>
+
+    SqlBuilder: Don't pass empty strings to the C functions.
+
+	* libgda/src/sqlbuilder.hg: Make sure that generated methods pass NULL
+    for empty strings, because libgda does not always check that strings are
+    not empty, though I try to fix that in libgda when I see it.
+
 2010-05-13  Murray Cumming  <murrayc murrayc com>
 
 	SqlBuilder: get_sql_statement(): Fix memory management.
-	
-	* libgda/src/sqlbuilder.hg: get_sql_statement(): Take a copy of the C object, 
+
+	* libgda/src/sqlbuilder.hg: get_sql_statement(): Take a copy of the C object,
 	to avoid a double-free.
 
 2010-05-12  Murray Cumming  <murrayc murrayc com>
diff --git a/libgda/src/sqlbuilder.hg b/libgda/src/sqlbuilder.hg
index d4fc43f..29d2b99 100644
--- a/libgda/src/sqlbuilder.hg
+++ b/libgda/src/sqlbuilder.hg
@@ -48,6 +48,8 @@ protected:
 public:
   _WRAP_CREATE(SqlStatementType type)
 
+#m4 _CONVERSION(`const Glib::ustring& ', `const gchar*', `string_or_null($3)')
+
   _WRAP_METHOD(Glib::RefPtr<Statement> get_statement() const, gda_sql_builder_get_statement, errthrow)
 
 #m4 _CONVERSION(`GdaSqlStatement*', `SqlStatement', `Glib::wrap($3, true /* take_copy */)')
diff --git a/tools/m4/convert_libgdamm.m4 b/tools/m4/convert_libgdamm.m4
index f049969..8ed27c0 100644
--- a/tools/m4/convert_libgdamm.m4
+++ b/tools/m4/convert_libgdamm.m4
@@ -158,4 +158,3 @@ _CONVERSION(`const SqlExpr&', `GdaSqlExpr*', `const_cast<GdaSqlExpr*>(($3).gobj(
 _CONVERSION(`GdaSqlExpr*', `SqlExpr', `Glib::wrap($3)')
 
 _CONVERSION(`const SqlStatement&', `GdaSqlStatement*', `const_cast<GdaSqlStatement*>(($3).gobj())')
-