record: add set_stream() and get_stream() using GIO

Use GInputStream for record stream manipulation

1 files changed, 155 insertions, 0 deletions

diff --git a/libmsi/libmsi-istream.c b/libmsi/libmsi-istream.c
new file mode 100644
index 0000000..85653e5
--- /dev/null
+++ b/libmsi/libmsi-istream.c
@@ -0,0 +1,155 @@
+/*
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include "msipriv.h"
+#include "libmsi-istream.h"
+
+struct _LibmsiIStream
+{
+    GInputStream parent;
+
+    GsfInput *input;
+};
+
+static void libmsi_seekable_iface_init (GSeekableIface  *iface);
+
+G_DEFINE_TYPE_WITH_CODE (LibmsiIStream, libmsi_istream, G_TYPE_INPUT_STREAM,
+                         G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE,
+                                                libmsi_seekable_iface_init);
+                         )
+
+static goffset
+libmsi_tell (GSeekable *seekable)
+{
+    g_return_val_if_fail (LIBMSI_IS_ISTREAM(seekable), FALSE);
+
+    return gsf_input_tell (LIBMSI_ISTREAM(seekable)->input);
+}
+
+static gboolean
+libmsi_can_seek (GSeekable *seekable)
+{
+    return TRUE;
+}
+
+static gboolean
+libmsi_seek (GSeekable *seekable, goffset offset,
+             GSeekType type, GCancellable *cancellable)
+{
+    g_return_val_if_fail (LIBMSI_IS_ISTREAM(seekable), FALSE);
+
+    return !gsf_input_seek (LIBMSI_ISTREAM(seekable)->input, offset, type);
+}
+
+static gboolean
+libmsi_can_truncate (GSeekable *seekable)
+{
+    return FALSE;
+}
+
+static void
+libmsi_seekable_iface_init (GSeekableIface *iface)
+{
+    iface->tell = libmsi_tell;
+    iface->can_seek = libmsi_can_seek;
+    iface->seek = libmsi_seek;
+    iface->can_truncate = libmsi_can_truncate;
+}
+
+static void
+libmsi_istream_init (LibmsiIStream *self)
+{
+}
+
+static void
+libmsi_istream_finalize (GObject *object)
+{
+    LibmsiIStream *self = LIBMSI_ISTREAM (object);
+
+    if (self->input)
+        g_object_unref (self->input);
+
+    G_OBJECT_CLASS (libmsi_istream_parent_class)->finalize (object);
+}
+
+static gssize
+input_stream_read (GInputStream  *stream,
+                   void *buffer,
+                   gsize count,
+                   GCancellable *cancellable,
+                   GError **error)
+{
+    LibmsiIStream *self = LIBMSI_ISTREAM (stream);
+    gssize remaining = gsf_input_remaining (self->input);
+
+    if (remaining == 0)
+        return 0;
+
+    count = MIN(count, remaining);
+    if (!gsf_input_read (self->input, count, buffer))
+        return -1;
+
+    return count;
+}
+
+static gssize
+input_stream_skip (GInputStream *stream,
+                   gsize count,
+                   GCancellable  *cancellable,
+                   GError **error)
+{
+    LibmsiIStream *self = LIBMSI_ISTREAM (stream);
+
+    count = MIN (count, gsf_input_remaining (self->input));
+    if (!gsf_input_seek (self->input, count, G_SEEK_CUR))
+        return -1;
+
+    return count;
+}
+
+static gboolean
+input_stream_close (GInputStream *stream,
+                    GCancellable *cancellable,
+                    GError **error)
+{
+    return TRUE;
+}
+
+static void
+libmsi_istream_class_init (LibmsiIStreamClass *klass)
+{
+    GObjectClass* object_class = G_OBJECT_CLASS (klass);
+    GInputStreamClass *istream_class;
+
+    object_class->finalize = libmsi_istream_finalize;
+
+    istream_class = G_INPUT_STREAM_CLASS (klass);
+    istream_class->read_fn = input_stream_read;
+    istream_class->skip  = input_stream_skip;
+    istream_class->close_fn = input_stream_close;
+}
+
+G_GNUC_INTERNAL LibmsiIStream *
+libmsi_istream_new (GsfInput *input)
+{
+    GsfInput *dup = gsf_input_dup (input, NULL);
+    g_return_val_if_fail (dup, NULL);
+
+    LibmsiIStream *self = g_object_new (LIBMSI_TYPE_ISTREAM, NULL);
+    self->input = dup;
+
+    return self;
+}