[glib] Add GConverterOutputStream
- From: Alexander Larsson <alexl src gnome org>
- To: svn-commits-list gnome org
- Cc:
- Subject: [glib] Add GConverterOutputStream
- Date: Mon, 23 Nov 2009 15:31:14 +0000 (UTC)
commit 7f8991596be1f17bd71c367bef630423f0a83c35
Author: Alexander Larsson <alexl redhat com>
Date: Mon Nov 23 15:03:57 2009 +0100
Add GConverterOutputStream
This allows for conversion when saving
gio/Makefile.am | 2 +
gio/gconverteroutputstream.c | 595 ++++++++++++++++++++++++++++++++++++++++++
gio/gconverteroutputstream.h | 80 ++++++
gio/gio.h | 1 +
gio/giotypes.h | 1 +
5 files changed, 679 insertions(+), 0 deletions(-)
---
diff --git a/gio/Makefile.am b/gio/Makefile.am
index b504def..34355d2 100644
--- a/gio/Makefile.am
+++ b/gio/Makefile.am
@@ -190,6 +190,7 @@ libgio_2_0_la_SOURCES = \
gcharsetconverter.c \
gconverter.c \
gconverterinputstream.c \
+ gconverteroutputstream.c \
gdatainputstream.c \
gdataoutputstream.c \
gdrive.c \
@@ -330,6 +331,7 @@ gio_headers = \
gcharsetconverter.h \
gconverter.h \
gconverterinputstream.h \
+ gconverteroutputstream.h \
gdatainputstream.h \
gdataoutputstream.h \
gdrive.h \
diff --git a/gio/gconverteroutputstream.c b/gio/gconverteroutputstream.c
new file mode 100644
index 0000000..f4c24b5
--- /dev/null
+++ b/gio/gconverteroutputstream.c
@@ -0,0 +1,595 @@
+/* GIO - GLib Input, Output and Streaming Library
+ *
+ * Copyright (C) 2009 Red Hat, Inc.
+ *
+ * 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 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., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Author: Alexander Larsson <alexl redhat com>
+ */
+
+#include "config.h"
+
+#include <string.h>
+
+#include "gconverteroutputstream.h"
+#include "gsimpleasyncresult.h"
+#include "gcancellable.h"
+#include "gioenumtypes.h"
+#include "gioerror.h"
+#include "glibintl.h"
+
+#include "gioalias.h"
+
+/**
+ * SECTION:gconverteroutputstream
+ * @short_description: Converter Output Stream
+ * @include: gio/gio.h
+ * @see_also: #GOutputStream, #GConverter
+ *
+ * Converter output stream implements #GOutputStream and allows
+ * conversion of data of various types during reading.
+ *
+ **/
+
+#define INITIAL_BUFFER_SIZE 4096
+
+typedef struct {
+ char *data;
+ gsize start;
+ gsize end;
+ gsize size;
+} Buffer;
+
+struct _GConverterOutputStreamPrivate {
+ gboolean at_output_end;
+ gboolean finished;
+ GConverter *converter;
+ Buffer output_buffer; /* To be converted and written */
+ Buffer converted_buffer; /* Already converted */
+};
+
+/* Buffering strategy:
+ *
+ * Each time we write we must at least consume some input, or
+ * return an error. Thus we start with writing all already
+ * converted data and *then* we start converting (reporting
+ * an error at any point in this).
+ *
+ * Its possible that what the user wrote is not enough data
+ * for the converter, so we must then buffer it in output_buffer
+ * and ask for more data, but we want to avoid this as much as
+ * possible, converting directly from the users buffer.
+ */
+
+enum {
+ PROP_0,
+ PROP_CONVERTER
+};
+
+static void g_converter_output_stream_set_property (GObject *object,
+ guint prop_id,
+ const GValue *value,
+ GParamSpec *pspec);
+static void g_converter_output_stream_get_property (GObject *object,
+ guint prop_id,
+ GValue *value,
+ GParamSpec *pspec);
+static void g_converter_output_stream_finalize (GObject *object);
+static gssize g_converter_output_stream_write (GOutputStream *stream,
+ const void *buffer,
+ gsize count,
+ GCancellable *cancellable,
+ GError **error);
+static gboolean g_converter_output_stream_flush (GOutputStream *stream,
+ GCancellable *cancellable,
+ GError **error);
+
+G_DEFINE_TYPE (GConverterOutputStream,
+ g_converter_output_stream,
+ G_TYPE_FILTER_OUTPUT_STREAM)
+
+static void
+g_converter_output_stream_class_init (GConverterOutputStreamClass *klass)
+{
+ GObjectClass *object_class;
+ GOutputStreamClass *istream_class;
+
+ g_type_class_add_private (klass, sizeof (GConverterOutputStreamPrivate));
+
+ object_class = G_OBJECT_CLASS (klass);
+ object_class->get_property = g_converter_output_stream_get_property;
+ object_class->set_property = g_converter_output_stream_set_property;
+ object_class->finalize = g_converter_output_stream_finalize;
+
+ istream_class = G_OUTPUT_STREAM_CLASS (klass);
+ istream_class->write_fn = g_converter_output_stream_write;
+ istream_class->flush = g_converter_output_stream_flush;
+
+ g_object_class_install_property (object_class,
+ PROP_CONVERTER,
+ g_param_spec_object ("converter",
+ P_("Converter"),
+ P_("The converter object"),
+ G_TYPE_CONVERTER,
+ G_PARAM_READWRITE|
+ G_PARAM_CONSTRUCT_ONLY|
+ G_PARAM_STATIC_STRINGS));
+
+}
+
+static void
+g_converter_output_stream_finalize (GObject *object)
+{
+ GConverterOutputStreamPrivate *priv;
+ GConverterOutputStream *stream;
+
+ stream = G_CONVERTER_OUTPUT_STREAM (object);
+ priv = stream->priv;
+
+ g_free (priv->output_buffer.data);
+ g_free (priv->converted_buffer.data);
+ if (priv->converter)
+ g_object_unref (priv->converter);
+
+ G_OBJECT_CLASS (g_converter_output_stream_parent_class)->finalize (object);
+}
+
+static void
+g_converter_output_stream_set_property (GObject *object,
+ guint prop_id,
+ const GValue *value,
+ GParamSpec *pspec)
+{
+ GConverterOutputStream *cstream;
+
+ cstream = G_CONVERTER_OUTPUT_STREAM (object);
+
+ switch (prop_id)
+ {
+ case PROP_CONVERTER:
+ cstream->priv->converter = g_value_dup_object (value);
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+
+}
+
+static void
+g_converter_output_stream_get_property (GObject *object,
+ guint prop_id,
+ GValue *value,
+ GParamSpec *pspec)
+{
+ GConverterOutputStreamPrivate *priv;
+ GConverterOutputStream *cstream;
+
+ cstream = G_CONVERTER_OUTPUT_STREAM (object);
+ priv = cstream->priv;
+
+ switch (prop_id)
+ {
+ case PROP_CONVERTER:
+ g_value_set_object (value, priv->converter);
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+
+}
+static void
+g_converter_output_stream_init (GConverterOutputStream *stream)
+{
+ stream->priv = G_TYPE_INSTANCE_GET_PRIVATE (stream,
+ G_TYPE_CONVERTER_OUTPUT_STREAM,
+ GConverterOutputStreamPrivate);
+}
+
+/**
+ * g_converter_output_stream_new:
+ * @base_stream: a #GOutputStream.
+ *
+ * Creates a new converter output stream for the @base_stream.
+ *
+ * Returns: a new #GConverterOutputStream.
+ **/
+GConverterOutputStream *
+g_converter_output_stream_new (GOutputStream *base_stream,
+ GConverter *converter)
+{
+ GConverterOutputStream *stream;
+
+ g_return_val_if_fail (G_IS_OUTPUT_STREAM (base_stream), NULL);
+
+ stream = g_object_new (G_TYPE_CONVERTER_OUTPUT_STREAM,
+ "base-stream", base_stream,
+ "converter", converter,
+ NULL);
+
+ return stream;
+}
+
+static gsize
+buffer_available (Buffer *buffer)
+{
+ return buffer->end - buffer->start;
+}
+
+static gsize
+buffer_tailspace (Buffer *buffer)
+{
+ return buffer->size - buffer->end;
+}
+
+static char *
+buffer_data (Buffer *buffer)
+{
+ return buffer->data + buffer->start;
+}
+
+static void
+buffer_consumed (Buffer *buffer,
+ gsize count)
+{
+ buffer->start += count;
+ if (buffer->start == buffer->end)
+ buffer->start = buffer->end = 0;
+}
+
+static void
+compact_buffer (Buffer *buffer)
+{
+ gsize in_buffer;
+
+ in_buffer = buffer_available (buffer);
+ memmove (buffer->data,
+ buffer->data + buffer->start,
+ in_buffer);
+ buffer->end -= buffer->start;
+ buffer->start = 0;
+}
+
+static void
+grow_buffer (Buffer *buffer)
+{
+ char *data;
+ gsize size, in_buffer;
+
+ if (buffer->size == 0)
+ size = INITIAL_BUFFER_SIZE;
+ else
+ size = buffer->size * 2;
+
+ data = g_malloc (size);
+ in_buffer = buffer_available (buffer);
+
+ memcpy (data,
+ buffer->data + buffer->start,
+ in_buffer);
+ g_free (buffer->data);
+ buffer->data = data;
+ buffer->end -= buffer->start;
+ buffer->start = 0;
+ buffer->size = size;
+}
+
+static void
+buffer_ensure_space (Buffer *buffer,
+ gsize at_least_size)
+{
+ gsize in_buffer, left_to_fill;
+
+ in_buffer = buffer_available (buffer);
+
+ if (in_buffer >= at_least_size)
+ return;
+
+ left_to_fill = buffer_tailspace (buffer);
+
+ if (in_buffer + left_to_fill >= at_least_size)
+ {
+ /* We fit in remaining space at end */
+ /* If the copy is small, compact now anyway so we can fill more */
+ if (in_buffer < 256)
+ compact_buffer (buffer);
+ }
+ else if (buffer->size >= at_least_size)
+ {
+ /* We fit, but only if we compact */
+ compact_buffer (buffer);
+ }
+ else
+ {
+ /* Need to grow buffer */
+ while (buffer->size < at_least_size)
+ grow_buffer (buffer);
+ }
+}
+
+static void
+buffer_append (Buffer *buffer,
+ const char *data,
+ gsize data_size)
+{
+ buffer_ensure_space (buffer,
+ buffer_available (buffer) + data_size);
+ memcpy (buffer->data + buffer->end, data, data_size);
+ buffer->end += data_size;
+}
+
+
+static gboolean
+flush_buffer (GConverterOutputStream *stream,
+ Buffer *buffer,
+ GCancellable *cancellable,
+ GError **error)
+{
+ GConverterOutputStreamPrivate *priv;
+ GOutputStream *base_stream;
+ gsize nwritten;
+ gsize available;
+ gboolean res;
+
+ priv = stream->priv;
+
+ base_stream = G_FILTER_OUTPUT_STREAM (stream)->base_stream;
+
+ available = buffer_available (&priv->converted_buffer);
+ if (available > 0)
+ {
+ res = g_output_stream_write_all (base_stream,
+ buffer_data (&priv->converted_buffer),
+ available,
+ &nwritten,
+ cancellable,
+ error);
+ buffer_consumed (&priv->converted_buffer, nwritten);
+ return res;
+ }
+ return TRUE;
+}
+
+
+static gssize
+g_converter_output_stream_write (GOutputStream *stream,
+ const void *buffer,
+ gsize count,
+ GCancellable *cancellable,
+ GError **error)
+{
+ GConverterOutputStream *cstream;
+ GConverterOutputStreamPrivate *priv;
+ gssize retval;
+ GConverterResult res;
+ gsize bytes_read;
+ gsize bytes_written;
+ GError *my_error;
+ const char *to_convert;
+ gsize to_convert_size, converted_bytes;
+ gboolean converting_from_buffer;
+
+ cstream = G_CONVERTER_OUTPUT_STREAM (stream);
+ priv = cstream->priv;
+
+ /* Write out all available pre-converted data and fail if
+ not possible */
+ if (!flush_buffer (cstream, &priv->converted_buffer, cancellable, error))
+ return -1;
+
+ if (priv->finished)
+ return 0;
+
+ /* Convert as much as possible */
+ if (buffer_available (&priv->output_buffer) > 0)
+ {
+ converting_from_buffer = TRUE;
+ buffer_append (&priv->output_buffer, buffer, count);
+ to_convert = buffer_data (&priv->output_buffer);
+ to_convert_size = buffer_available (&priv->output_buffer);
+ }
+ else
+ {
+ converting_from_buffer = FALSE;
+ to_convert = buffer;
+ to_convert_size = count;
+ }
+
+ /* Ensure we have *some* initial target space */
+ buffer_ensure_space (&priv->converted_buffer, to_convert_size);
+
+ converted_bytes = 0;
+ while (!priv->finished && converted_bytes < to_convert_size)
+ {
+ /* Try to convert to our buffer */
+ my_error = NULL;
+ res = g_converter_convert (priv->converter,
+ to_convert + converted_bytes,
+ to_convert_size - converted_bytes,
+ buffer_data (&priv->converted_buffer),
+ buffer_tailspace (&priv->converted_buffer),
+ 0,
+ &bytes_read,
+ &bytes_written,
+ &my_error);
+
+ if (res != G_CONVERTER_ERROR)
+ {
+ priv->converted_buffer.end += bytes_written;
+ converted_bytes += bytes_read;
+
+ if (res == G_CONVERTER_FINISHED)
+ priv->finished = TRUE;
+ }
+ else
+ {
+ /* No-space errors can be handled locally: */
+ if (g_error_matches (my_error,
+ G_IO_ERROR,
+ G_IO_ERROR_NO_SPACE))
+ {
+ /* Need more destination space, grow it
+ * Note: if we actually grow the buffer (as opposed to compacting it),
+ * this will double the size, not just add one byte. */
+ buffer_ensure_space (&priv->converted_buffer,
+ priv->converted_buffer.size + 1);
+ g_error_free (my_error);
+ continue;
+ }
+
+ if (converted_bytes > 0)
+ {
+ /* We got an conversion error, but we did convert some bytes before
+ that, so handle those before reporting the error */
+ g_error_free (my_error);
+ break;
+ }
+
+ if (g_error_matches (my_error,
+ G_IO_ERROR,
+ G_IO_ERROR_PARTIAL_INPUT))
+ {
+ /* Consume everything to buffer that we append to next time
+ we write */
+ if (!converting_from_buffer)
+ buffer_append (&priv->output_buffer, buffer, count);
+ /* in the converting_from_buffer case we already appended this */
+
+ return count; /* consume everything */
+ }
+
+ /* Converted no data and got an normal error, return it */
+ g_propagate_error (error, my_error);
+ return -1;
+ }
+ }
+
+ if (converting_from_buffer)
+ {
+ buffer_consumed (&priv->output_buffer, converted_bytes);
+ retval = count;
+ }
+ else
+ retval = converted_bytes;
+
+ /* We now successfully consumed retval bytes, so we can't return an error,
+ even if writing this to the base stream fails. If it does we'll just
+ stop early and report this error when we try again on the next
+ write call. */
+ flush_buffer (cstream, &priv->converted_buffer, cancellable, NULL);
+
+ return retval;
+}
+
+static gboolean
+g_converter_output_stream_flush (GOutputStream *stream,
+ GCancellable *cancellable,
+ GError **error)
+{
+ GConverterOutputStream *cstream;
+ GConverterOutputStreamPrivate *priv;
+ GConverterResult res;
+ GError *my_error;
+ gboolean is_closing;
+ gboolean flushed;
+ gsize bytes_read;
+ gsize bytes_written;
+
+ cstream = G_CONVERTER_OUTPUT_STREAM (stream);
+ priv = cstream->priv;
+
+ is_closing = g_output_stream_is_closing (stream);
+
+ /* Write out all available pre-converted data and fail if
+ not possible */
+ if (!flush_buffer (cstream, &priv->converted_buffer, cancellable, error))
+ return FALSE;
+
+ /* Ensure we have *some* initial target space */
+ buffer_ensure_space (&priv->converted_buffer, 1);
+
+ /* Convert whole buffer */
+ flushed = FALSE;
+ while (!priv->finished && !flushed)
+ {
+ /* Try to convert to our buffer */
+ my_error = NULL;
+ res = g_converter_convert (priv->converter,
+ buffer_data (&priv->output_buffer),
+ buffer_available (&priv->output_buffer),
+ buffer_data (&priv->converted_buffer),
+ buffer_tailspace (&priv->converted_buffer),
+ is_closing ? G_CONVERTER_INPUT_AT_END : G_CONVERTER_FLUSH,
+ &bytes_read,
+ &bytes_written,
+ &my_error);
+
+ if (res != G_CONVERTER_ERROR)
+ {
+ priv->converted_buffer.end += bytes_written;
+ buffer_consumed (&priv->output_buffer, bytes_read);
+
+ if (res == G_CONVERTER_FINISHED)
+ priv->finished = TRUE;
+ if (!is_closing &&
+ res == G_CONVERTER_FLUSHED)
+ {
+ /* Should not have retured FLUSHED with input left */
+ g_assert (buffer_available (&priv->output_buffer) == 0);
+ flushed = TRUE;
+ }
+ }
+ else
+ {
+ /* No-space errors can be handled locally: */
+ if (g_error_matches (my_error,
+ G_IO_ERROR,
+ G_IO_ERROR_NO_SPACE))
+ {
+ /* Need more destination space, grow it
+ * Note: if we actually grow the buffer (as opposed to compacting it),
+ * this will double the size, not just add one byte. */
+ buffer_ensure_space (&priv->converted_buffer,
+ priv->converted_buffer.size + 1);
+ g_error_free (my_error);
+ continue;
+ }
+
+ /* Any other error, including PARTIAL_INPUT can't be fixed by now
+ and is an error */
+ g_propagate_error (error, my_error);
+ return -1;
+ }
+ }
+
+ /* Now write all converted data to base stream */
+ if (!flush_buffer (cstream, &priv->converted_buffer, cancellable, error))
+ return FALSE;
+
+ return TRUE;
+}
+
+GConverter *
+g_converter_output_stream_get_converter (GConverterOutputStream *converter_stream)
+{
+ return converter_stream->priv->converter;
+}
+
+#define __G_CONVERTER_OUTPUT_STREAM_C__
+#include "gioaliasdef.c"
diff --git a/gio/gconverteroutputstream.h b/gio/gconverteroutputstream.h
new file mode 100644
index 0000000..1e89560
--- /dev/null
+++ b/gio/gconverteroutputstream.h
@@ -0,0 +1,80 @@
+/* GIO - GLib Input, Output and Streaming Library
+ *
+ * Copyright (C) 2009 Red Hat, Inc.
+ *
+ * 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 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., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Author: Alexander Larsson <alexl redhat com>
+ */
+
+#if !defined (__GIO_GIO_H_INSIDE__) && !defined (GIO_COMPILATION)
+#error "Only <gio/gio.h> can be included directly."
+#endif
+
+#ifndef __G_CONVERTER_OUTPUT_STREAM_H__
+#define __G_CONVERTER_OUTPUT_STREAM_H__
+
+#include <gio/gfilteroutputstream.h>
+#include <gio/gconverter.h>
+
+G_BEGIN_DECLS
+
+#define G_TYPE_CONVERTER_OUTPUT_STREAM (g_converter_output_stream_get_type ())
+#define G_CONVERTER_OUTPUT_STREAM(o) (G_TYPE_CHECK_INSTANCE_CAST ((o), G_TYPE_CONVERTER_OUTPUT_STREAM, GConverterOutputStream))
+#define G_CONVERTER_OUTPUT_STREAM_CLASS(k) (G_TYPE_CHECK_CLASS_CAST((k), G_TYPE_CONVERTER_OUTPUT_STREAM, GConverterOutputStreamClass))
+#define G_IS_CONVERTER_OUTPUT_STREAM(o) (G_TYPE_CHECK_INSTANCE_TYPE ((o), G_TYPE_CONVERTER_OUTPUT_STREAM))
+#define G_IS_CONVERTER_OUTPUT_STREAM_CLASS(k) (G_TYPE_CHECK_CLASS_TYPE ((k), G_TYPE_CONVERTER_OUTPUT_STREAM))
+#define G_CONVERTER_OUTPUT_STREAM_GET_CLASS(o) (G_TYPE_INSTANCE_GET_CLASS ((o), G_TYPE_CONVERTER_OUTPUT_STREAM, GConverterOutputStreamClass))
+
+/**
+ * GConverterOutputStream:
+ * @parent: a #GFilterOutputStream.
+ *
+ * An implementation of #GFilterOutputStream that allows data
+ * conversion.
+ **/
+typedef struct _GConverterOutputStreamClass GConverterOutputStreamClass;
+typedef struct _GConverterOutputStreamPrivate GConverterOutputStreamPrivate;
+
+struct _GConverterOutputStream
+{
+ GFilterOutputStream parent_instance;
+
+ /*< private >*/
+ GConverterOutputStreamPrivate *priv;
+};
+
+struct _GConverterOutputStreamClass
+{
+ GFilterOutputStreamClass parent_class;
+
+ /*< private >*/
+ /* Padding for future expansion */
+ void (*_g_reserved1) (void);
+ void (*_g_reserved2) (void);
+ void (*_g_reserved3) (void);
+ void (*_g_reserved4) (void);
+ void (*_g_reserved5) (void);
+};
+
+GType g_converter_output_stream_get_type (void) G_GNUC_CONST;
+GConverterOutputStream *g_converter_output_stream_new (GOutputStream *base_stream,
+ GConverter *converter);
+GConverter *g_converter_output_stream_get_converter (GConverterOutputStream *converter_stream);
+
+G_END_DECLS
+
+#endif /* __G_CONVERTER_OUTPUT_STREAM_H__ */
diff --git a/gio/gio.h b/gio/gio.h
index c59e59b..9f3410d 100644
--- a/gio/gio.h
+++ b/gio/gio.h
@@ -36,6 +36,7 @@
#include <gio/gcontenttype.h>
#include <gio/gconverter.h>
#include <gio/gconverterinputstream.h>
+#include <gio/gconverteroutputstream.h>
#include <gio/gcharsetconverter.h>
#include <gio/gdatainputstream.h>
#include <gio/gdataoutputstream.h>
diff --git a/gio/giotypes.h b/gio/giotypes.h
index 2b80c45..8c00891 100644
--- a/gio/giotypes.h
+++ b/gio/giotypes.h
@@ -41,6 +41,7 @@ typedef struct _GCancellable GCancellable;
typedef struct _GCharsetConverter GCharsetConverter;
typedef struct _GConverter GConverter;
typedef struct _GConverterInputStream GConverterInputStream;
+typedef struct _GConverterOutputStream GConverterOutputStream;
typedef struct _GDataInputStream GDataInputStream;
/**
[
Date Prev][
Date Next] [
Thread Prev][
Thread Next]
[
Thread Index]
[
Date Index]
[
Author Index]
