[gtksourceview/wip/loader-saver] Make BufferOutputStream more robust after dispose

[Sébastien Wilmet <swilmet src gnome org>]

commit 7d46184cadf514cb4b2cc09c935c2898981375e5
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Mon Jun 23 12:37:45 2014 +0200

    Make BufferOutputStream more robust after dispose
    
    Some code can be executed after dispose(), like
    gtk_source_buffer_output_stream_close(). After dispose(), the
    source_buffer is NULL.

 gtksourceview/gtksourcebufferoutputstream.c |   38 +++++++++++++++++++++++---
 1 files changed, 33 insertions(+), 5 deletions(-)
---
diff --git a/gtksourceview/gtksourcebufferoutputstream.c b/gtksourceview/gtksourcebufferoutputstream.c
index 883238f..235d7e3 100644
--- a/gtksourceview/gtksourcebufferoutputstream.c
+++ b/gtksourceview/gtksourcebufferoutputstream.c
@@ -496,6 +496,11 @@ gtk_source_buffer_output_stream_detect_newline_type (GtkSourceBufferOutputStream
        g_return_val_if_fail (GTK_SOURCE_IS_BUFFER_OUTPUT_STREAM (stream),
                              GTK_SOURCE_NEWLINE_TYPE_DEFAULT);
 
+       if (stream->priv->source_buffer == NULL)
+       {
+               return GTK_SOURCE_NEWLINE_TYPE_DEFAULT;
+       }
+
        type = GTK_SOURCE_NEWLINE_TYPE_DEFAULT;
 
        gtk_text_buffer_get_start_iter (GTK_TEXT_BUFFER (stream->priv->source_buffer),
@@ -542,7 +547,8 @@ apply_error_tag (GtkSourceBufferOutputStream *stream)
 {
        GtkTextIter start;
 
-       if (stream->priv->error_offset == -1)
+       if (stream->priv->error_offset == -1 ||
+           stream->priv->source_buffer == NULL)
        {
                return;
        }
@@ -565,6 +571,11 @@ insert_fallback (GtkSourceBufferOutputStream *stream,
        guint8 v;
        const gchar hex[] = "0123456789ABCDEF";
 
+       if (stream->priv->source_buffer == NULL)
+       {
+               return;
+       }
+
        /* If we are here it is because we are pointing to an invalid char so we
         * substitute it by an hex value.
         */
@@ -589,6 +600,11 @@ validate_and_insert (GtkSourceBufferOutputStream *stream,
        GtkTextIter *iter;
        gsize len;
 
+       if (stream->priv->source_buffer == NULL)
+       {
+               return;
+       }
+
        text_buffer = GTK_TEXT_BUFFER (stream->priv->source_buffer);
        iter = &stream->priv->pos;
        len = count;
@@ -671,6 +687,11 @@ remove_trailing_newline (GtkSourceBufferOutputStream *stream)
        GtkTextIter end;
        GtkTextIter start;
 
+       if (stream->priv->source_buffer == NULL)
+       {
+               return;
+       }
+
        gtk_text_buffer_get_end_iter (GTK_TEXT_BUFFER (stream->priv->source_buffer), &end);
        start = end;
 
@@ -693,6 +714,11 @@ remove_trailing_newline (GtkSourceBufferOutputStream *stream)
 static void
 end_append_text_to_document (GtkSourceBufferOutputStream *stream)
 {
+       if (stream->priv->source_buffer == NULL)
+       {
+               return;
+       }
+
        if (stream->priv->remove_trailing_newline)
        {
                remove_trailing_newline (stream);
@@ -812,13 +838,14 @@ gtk_source_buffer_output_stream_write (GOutputStream  *stream,
        gsize len;
        gboolean freetext = FALSE;
 
-       if (g_cancellable_set_error_if_cancelled (cancellable, error))
+       ostream = GTK_SOURCE_BUFFER_OUTPUT_STREAM (stream);
+
+       if (g_cancellable_set_error_if_cancelled (cancellable, error) ||
+           ostream->priv->source_buffer == NULL)
        {
                return -1;
        }
 
-       ostream = GTK_SOURCE_BUFFER_OUTPUT_STREAM (stream);
-
        if (!ostream->priv->is_initialized)
        {
                ostream->priv->charset_conv = guess_encoding (ostream, buffer, count);
@@ -992,7 +1019,8 @@ gtk_source_buffer_output_stream_flush (GOutputStream  *stream,
 
        ostream = GTK_SOURCE_BUFFER_OUTPUT_STREAM (stream);
 
-       if (ostream->priv->is_closed)
+       if (ostream->priv->is_closed ||
+           ostream->priv->source_buffer == NULL)
        {
                return TRUE;
        }