bytewriter: Add a generic byte writer

Fixes bug #590669.

3 files changed, 974 insertions, 0 deletions

diff --git a/libs/gst/base/Makefile.am b/libs/gst/base/Makefile.am
index b5220c4e01..91733b40ca 100644
--- a/libs/gst/base/Makefile.am
+++ b/libs/gst/base/Makefile.am
@@ -9,6 +9,7 @@ libgstbase_@GST_MAJORMINOR@_la_SOURCES = \
 	gstbasetransform.c	\
 	gstbitreader.c		\
 	gstbytereader.c		\
+	gstbytewriter.c         \
 	gstcollectpads.c	\
 	gstpushsrc.c		\
 	gsttypefindhelper.c	\
@@ -28,6 +29,7 @@ libgstbase_@GST_MAJORMINOR@include_HEADERS =	\
 	gstbasetransform.h	\
 	gstbitreader.h		\
 	gstbytereader.h		\
+	gstbytewriter.h         \
 	gstcollectpads.h	\
 	gstpushsrc.h		\
 	gsttypefindhelper.h	\
diff --git a/libs/gst/base/gstbytewriter.c b/libs/gst/base/gstbytewriter.c
new file mode 100644
index 0000000000..7b5d3fa108
--- /dev/null
+++ b/libs/gst/base/gstbytewriter.c
@@ -0,0 +1,805 @@
+/* GStreamer byte writer
+ *
+ * Copyright (C) 2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstbytewriter.h"
+#include <string.h>
+
+/**
+ * SECTION:gstbytewriter
+ * @short_description: Writes different integer, string and floating point
+ *     types to a memory buffer and allows reading
+ *
+ * #GstByteWriter provides a byte writer and reader that can write/read different
+ * integer and floating point types to/from a memory buffer. It provides functions
+ * for writing/reading signed/unsigned, little/big endian integers of 8, 16, 24,
+ * 32 and 64 bits and functions for reading little/big endian floating points numbers of
+ * 32 and 64 bits. It also provides functions to write/read NUL-terminated strings
+ * in various character encodings.
+ */
+
+/**
+ * gst_byte_writer_new:
+ *
+ * Creates a new, empty #GstByteWriter instance
+ *
+ * Returns: a new, empty #GstByteWriter instance
+ *
+ * Since: 0.10.26
+ */
+GstByteWriter *
+gst_byte_writer_new (void)
+{
+  GstByteWriter *ret = g_slice_new0 (GstByteWriter);
+
+  ret->owned = TRUE;
+  return ret;
+}
+
+/**
+ * gst_byte_writer_new_with_size:
+ * @size: Initial size of data
+ * @fixed: If %TRUE the data can't be reallocated
+ *
+ * Creates a new #GstByteWriter instance with the given
+ * initial data size.
+ *
+ * Returns: a new #GstByteWriter instance
+ *
+ * Since: 0.10.26
+ */
+GstByteWriter *
+gst_byte_writer_new_with_size (guint size, gboolean fixed)
+{
+  GstByteWriter *ret = gst_byte_writer_new ();
+
+  ret->alloc_size = size;
+  ret->parent.data = g_malloc (ret->alloc_size);
+  ret->fixed = fixed;
+  ret->owned = TRUE;
+
+  return ret;
+}
+
+/**
+ * gst_byte_writer_new_with_data:
+ * @data: Memory area for writing
+ * @size: Size of @data in bytes
+ * @initialized: If %TRUE the complete data can be read from the beginning
+ *
+ * Creates a new #GstByteWriter instance with the given
+ * memory area. If @initialized is %TRUE it is possible to
+ * read @size bytes from the #GstByteWriter from the beginning.
+ *
+ * Returns: a new #GstByteWriter instance
+ *
+ * Since: 0.10.26
+ */
+GstByteWriter *
+gst_byte_writer_new_with_data (guint8 * data, guint size, gboolean initialized)
+{
+  GstByteWriter *ret = gst_byte_writer_new ();
+
+  ret->parent.data = data;
+  ret->parent.size = (initialized) ? size : 0;
+  ret->alloc_size = size;
+  ret->fixed = TRUE;
+  ret->owned = FALSE;
+
+  return ret;
+}
+
+/**
+ * gst_byte_writer_new_with_buffer:
+ * @buffer: Buffer used for writing
+ * @initialized: If %TRUE the complete data can be read from the beginning
+ *
+ * Creates a new #GstByteWriter instance with the given
+ * buffer. If @initialized is %TRUE it is possible to
+ * read the complete buffer from the #GstByteWriter from the beginning.
+ *
+ * <note>@buffer must be writable</note>
+ *
+ * Returns: a new #GstByteWriter instance
+ *
+ * Since: 0.10.26
+ */
+GstByteWriter *
+gst_byte_writer_new_with_buffer (GstBuffer * buffer, gboolean initialized)
+{
+  g_return_val_if_fail (GST_IS_BUFFER (buffer)
+      && gst_buffer_is_writable (buffer), NULL);
+
+  return gst_byte_writer_new_with_data (GST_BUFFER_DATA (buffer),
+      GST_BUFFER_SIZE (buffer), initialized);
+}
+
+/**
+ * gst_byte_writer_init:
+ * @writer: #GstByteWriter instance
+ *
+ * Initializes @writer to an empty instance
+ *
+ * Since: 0.10.26
+ */
+void
+gst_byte_writer_init (GstByteWriter * writer)
+{
+  g_return_if_fail (writer != NULL);
+
+  memset (writer, 0, sizeof (GstByteWriter));
+
+  writer->owned = TRUE;
+}
+
+/**
+ * gst_byte_writer_init_with_size:
+ * @writer: #GstByteWriter instance
+ * @size: Initial size of data
+ * @fixed: If %TRUE the data can't be reallocated
+ *
+ * Initializes @writer with the given initial data size.
+ *
+ * Since: 0.10.26
+ */
+void
+gst_byte_writer_init_with_size (GstByteWriter * writer, guint size,
+    gboolean fixed)
+{
+  g_return_if_fail (writer != NULL);
+
+  gst_byte_writer_init (writer);
+
+  writer->parent.data = g_malloc (size);
+  writer->alloc_size = size;
+  writer->fixed = fixed;
+  writer->owned = TRUE;
+}
+
+/**
+ * gst_byte_writer_init_with_data:
+ * @writer: #GstByteWriter instance
+ * @data: Memory area for writing
+ * @size: Size of @data in bytes
+ * @initialized: If %TRUE the complete data can be read from the beginning
+ *
+ * Initializes @writer with the given
+ * memory area. If @initialized is %TRUE it is possible to
+ * read @size bytes from the #GstByteWriter from the beginning.
+ *
+ * Since: 0.10.26
+ */
+void
+gst_byte_writer_init_with_data (GstByteWriter * writer, guint8 * data,
+    guint size, gboolean initialized)
+{
+  g_return_if_fail (writer != NULL);
+
+  gst_byte_writer_init (writer);
+
+  writer->parent.data = data;
+  writer->parent.size = (initialized) ? size : 0;
+  writer->alloc_size = size;
+  writer->fixed = TRUE;
+  writer->owned = FALSE;
+}
+
+/**
+ * gst_byte_writer_init_with_buffer:
+ * @writer: #GstByteWriter instance
+ * @buffer: Buffer used for writing
+ * @initialized: If %TRUE the complete data can be read from the beginning
+ *
+ * Initializes @writer with the given
+ * buffer. If @initialized is %TRUE it is possible to
+ * read the complete buffer from the #GstByteWriter from the beginning.
+ *
+ * <note>@buffer must be writable</note>
+ *
+ * Since: 0.10.26
+ */
+void
+gst_byte_writer_init_with_buffer (GstByteWriter * writer, GstBuffer * buffer,
+    gboolean initialized)
+{
+  g_return_if_fail (GST_IS_BUFFER (buffer) && gst_buffer_is_writable (buffer));
+
+  gst_byte_writer_init_with_data (writer, GST_BUFFER_DATA (buffer),
+      GST_BUFFER_SIZE (buffer), initialized);
+}
+
+/**
+ * gst_byte_writer_reset:
+ * @writer: #GstByteWriter instance
+ *
+ * Resets @writer and frees the data if it's
+ * owned by @writer.
+ *
+ * Since: 0.10.26
+ */
+void
+gst_byte_writer_reset (GstByteWriter * writer)
+{
+  g_return_if_fail (writer != NULL);
+
+  if (writer->owned)
+    g_free ((guint8 *) writer->parent.data);
+  memset (writer, 0, sizeof (GstByteWriter));
+}
+
+/**
+ * gst_byte_writer_reset_and_get_data:
+ * @writer: #GstByteWriter instance
+ *
+ * Resets @writer and returns the current data.
+ *
+ * Returns: the current data. g_free() after usage.
+ *
+ * Since: 0.10.26
+ */
+guint8 *
+gst_byte_writer_reset_and_get_data (GstByteWriter * writer)
+{
+  guint8 *data;
+
+  g_return_val_if_fail (writer != NULL, NULL);
+
+  data = (guint8 *) writer->parent.data;
+  if (!writer->owned)
+    data = g_memdup (data, writer->parent.size);
+  writer->parent.data = NULL;
+  gst_byte_writer_reset (writer);
+
+  return data;
+}
+
+/**
+ * gst_byte_writer_reset_and_get_buffer:
+ * @writer: #GstByteWriter instance
+ *
+ * Resets @writer and returns the current data as buffer.
+ *
+ * Returns: the current data as buffer. gst_buffer_unref() after usage.
+ *
+ * Since: 0.10.26
+ */
+GstBuffer *
+gst_byte_writer_reset_and_get_buffer (GstByteWriter * writer)
+{
+  GstBuffer *buffer;
+
+  g_return_val_if_fail (writer != NULL, NULL);
+
+  buffer = gst_buffer_new ();
+  GST_BUFFER_SIZE (buffer) = writer->parent.size;
+  GST_BUFFER_MALLOCDATA (buffer) = gst_byte_writer_reset_and_get_data (writer);
+  GST_BUFFER_DATA (buffer) = GST_BUFFER_MALLOCDATA (buffer);
+
+  return buffer;
+}
+
+/**
+ * gst_byte_writer_free:
+ * @writer: #GstByteWriter instance
+ *
+ * Frees @writer and all memory allocated by it.
+ *
+ * Since: 0.10.26
+ */
+void
+gst_byte_writer_free (GstByteWriter * writer)
+{
+  g_return_if_fail (writer != NULL);
+
+  gst_byte_writer_reset (writer);
+  g_slice_free (GstByteWriter, writer);
+}
+
+/**
+ * gst_byte_writer_free_and_get_data:
+ * @writer: #GstByteWriter instance
+ *
+ * Frees @writer and all memory allocated by it except
+ * the current data, which is returned.
+ *
+ * Returns: the current data. g_free() after usage.
+ *
+ * Since: 0.10.26
+ */
+guint8 *
+gst_byte_writer_free_and_get_data (GstByteWriter * writer)
+{
+  guint8 *data;
+
+  g_return_val_if_fail (writer != NULL, NULL);
+
+  data = gst_byte_writer_reset_and_get_data (writer);
+  g_slice_free (GstByteWriter, writer);
+
+  return data;
+}
+
+/**
+ * gst_byte_writer_free_and_get_buffer:
+ * @writer: #GstByteWriter instance
+ *
+ * Frees @writer and all memory allocated by it except
+ * the current data, which is returned as #GstBuffer.
+ *
+ * Returns: the current data as buffer. gst_buffer_unref() after usage.
+ *
+ * Since: 0.10.26
+ */
+GstBuffer *
+gst_byte_writer_free_and_get_buffer (GstByteWriter * writer)
+{
+  GstBuffer *buffer;
+
+  g_return_val_if_fail (writer != NULL, NULL);
+
+  buffer = gst_byte_writer_reset_and_get_buffer (writer);
+  g_slice_free (GstByteWriter, writer);
+
+  return buffer;
+}
+
+/**
+ * gst_byte_writer_get_remaining:
+ * @writer: #GstByteWriter instance
+ *
+ * Returns the remaining size of data that can still be written. If
+ * -1 is returned the remaining size is only limited by system resources.
+ *
+ * Returns: the remaining size of data that can still be written
+ *
+ * Since: 0.10.26
+ */
+guint
+gst_byte_writer_get_remaining (const GstByteWriter * writer)
+{
+  g_return_val_if_fail (writer != NULL, -1);
+
+  if (!writer->fixed)
+    return -1;
+  else
+    return writer->alloc_size - writer->parent.byte;
+}
+
+static guint
+_next_pow2 (guint n)
+{
+  guint ret = 16;
+
+  /* We start with 16, smaller allocations make no sense */
+
+  while (ret < n)
+    ret <<= 1;
+
+  return ret;
+}
+
+/**
+ * gst_byte_writer_ensure_free_space:
+ * @writer: #GstByteWriter instance
+ * @size: Number of bytes that should be available
+ *
+ * Checks if enough free space from the current write cursor is
+ * available and reallocates if necessary.
+ *
+ * Returns: %TRUE if at least @size bytes are still available
+ *
+ * Since: 0.10.26
+ */
+gboolean
+gst_byte_writer_ensure_free_space (GstByteWriter * writer, guint size)
+{
+  guint8 *data;
+
+  if (G_UNLIKELY (size <= writer->alloc_size - writer->parent.byte))
+    return TRUE;
+  if (G_UNLIKELY (writer->fixed || !writer->owned))
+    return FALSE;
+  if (G_UNLIKELY (writer->parent.byte > G_MAXUINT - size))
+    return FALSE;
+
+  writer->alloc_size = _next_pow2 (writer->parent.byte + size);
+  data = g_try_realloc ((guint8 *) writer->parent.data, writer->alloc_size);
+  if (G_UNLIKELY (data == NULL))
+    return FALSE;
+
+  writer->parent.data = data;
+
+  return TRUE;
+}
+
+
+#define CREATE_WRITE_FUNC(bits,type,name,write_func) \
+gboolean \
+gst_byte_writer_put_##name (GstByteWriter *writer, type val) \
+{ \
+  g_return_val_if_fail (writer != NULL, FALSE); \
+  \
+  if (G_UNLIKELY (!gst_byte_writer_ensure_free_space(writer, bits/8))) \
+    return FALSE; \
+  \
+  write_func ((guint8 *) &writer->parent.data[writer->parent.byte], val); \
+  writer->parent.byte += bits/8; \
+  writer->parent.size = MAX (writer->parent.size, writer->parent.byte); \
+  \
+  return TRUE; \
+}
+
+CREATE_WRITE_FUNC (8, guint8, uint8, GST_WRITE_UINT8);
+CREATE_WRITE_FUNC (8, gint8, int8, GST_WRITE_UINT8);
+CREATE_WRITE_FUNC (16, guint16, uint16_le, GST_WRITE_UINT16_LE);
+CREATE_WRITE_FUNC (16, guint16, uint16_be, GST_WRITE_UINT16_BE);
+CREATE_WRITE_FUNC (16, gint16, int16_le, GST_WRITE_UINT16_LE);
+CREATE_WRITE_FUNC (16, gint16, int16_be, GST_WRITE_UINT16_BE);
+CREATE_WRITE_FUNC (24, guint32, uint24_le, GST_WRITE_UINT24_LE);
+CREATE_WRITE_FUNC (24, guint32, uint24_be, GST_WRITE_UINT24_BE);
+CREATE_WRITE_FUNC (24, gint32, int24_le, GST_WRITE_UINT24_LE);
+CREATE_WRITE_FUNC (24, gint32, int24_be, GST_WRITE_UINT24_BE);
+CREATE_WRITE_FUNC (32, guint32, uint32_le, GST_WRITE_UINT32_LE);
+CREATE_WRITE_FUNC (32, guint32, uint32_be, GST_WRITE_UINT32_BE);
+CREATE_WRITE_FUNC (32, gint32, int32_le, GST_WRITE_UINT32_LE);
+CREATE_WRITE_FUNC (32, gint32, int32_be, GST_WRITE_UINT32_BE);
+CREATE_WRITE_FUNC (64, guint64, uint64_le, GST_WRITE_UINT64_LE);
+CREATE_WRITE_FUNC (64, guint64, uint64_be, GST_WRITE_UINT64_BE);
+CREATE_WRITE_FUNC (64, gint64, int64_le, GST_WRITE_UINT64_LE);
+CREATE_WRITE_FUNC (64, gint64, int64_be, GST_WRITE_UINT64_BE);
+
+CREATE_WRITE_FUNC (32, gfloat, float32_be, GST_WRITE_FLOAT_BE);
+CREATE_WRITE_FUNC (32, gfloat, float32_le, GST_WRITE_FLOAT_LE);
+CREATE_WRITE_FUNC (64, gdouble, float64_be, GST_WRITE_DOUBLE_BE);
+CREATE_WRITE_FUNC (64, gdouble, float64_le, GST_WRITE_DOUBLE_LE);
+
+gboolean
+gst_byte_writer_put_data (GstByteWriter * writer, const guint8 * data,
+    guint size)
+{
+  g_return_val_if_fail (writer != NULL, FALSE);
+
+  if (G_UNLIKELY (!gst_byte_writer_ensure_free_space (writer, size)))
+    return FALSE;
+
+  memcpy ((guint8 *) & writer->parent.data[writer->parent.byte], data, size);
+  writer->parent.byte += size;
+  writer->parent.size = MAX (writer->parent.size, writer->parent.byte);
+
+  return TRUE;
+}
+
+#define CREATE_WRITE_STRING_FUNC(bits,type) \
+gboolean \
+gst_byte_writer_put_string_utf##bits (GstByteWriter *writer, const type * data) \
+{ \
+  guint size = 0; \
+  g_return_val_if_fail (writer != NULL, FALSE); \
+  \
+  /* endianness does not matter if we are looking for a NUL terminator */ \
+  while (data[size] != 0) { \
+    /* have prevent overflow */ \
+    if (G_UNLIKELY (size == G_MAXUINT)) \
+      return FALSE; \
+    ++size; \
+  } \
+  ++size; \
+  \
+  if (G_UNLIKELY (!gst_byte_writer_ensure_free_space(writer, size * (bits / 8)))) \
+    return FALSE; \
+  \
+  gst_byte_writer_put_data (writer, (const guint8 *) data, size * (bits / 8)); \
+  \
+  return TRUE; \
+}
+
+CREATE_WRITE_STRING_FUNC (8, gchar);
+CREATE_WRITE_STRING_FUNC (16, guint16);
+CREATE_WRITE_STRING_FUNC (32, guint32);
+/**
+ * gst_byte_writer_put_uint8:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned 8 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_uint16_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned big endian 16 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_uint24_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned big endian 24 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_uint32_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned big endian 32 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_uint64_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned big endian 64 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_uint16_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned little endian 16 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_uint24_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned little endian 24 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_uint32_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned little endian 32 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_uint64_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a unsigned little endian 64 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int8:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed 8 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int16_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed big endian 16 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int24_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed big endian 24 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int32_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed big endian 32 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int64_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed big endian 64 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int16_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed little endian 16 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int24_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed little endian 24 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int32_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed little endian 32 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_int64_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a signed little endian 64 bit integer to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_float_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a big endian 32 bit float to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_double_be:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a big endian 64 bit float to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_float_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a little endian 32 bit float to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_double_le:
+ * @writer: #GstByteWriter instance
+ * @val: Value to write
+ *
+ * Writes a little endian 64 bit float to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_string_utf8:
+ * @writer: #GstByteWriter instance
+ * @data: UTF8 string to write
+ *
+ * Writes a null-terminated UTF8 string to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_string_utf16:
+ * @writer: #GstByteWriter instance
+ * @data: UTF16 string to write
+ *
+ * Writes a null-terminated UTF16 string to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_string_utf32:
+ * @writer: #GstByteWriter instance
+ * @data: UTF32 string to write
+ *
+ * Writes a null-terminated UTF32 string to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_put_data:
+ * @writer: #GstByteWriter instance
+ * @data: Data to write
+ * @size: Size of @data in bytes
+ *
+ * Writes @size bytes of @data to @writer.
+ *
+ * Returns: %TRUE if the value could be written
+ *
+ * Since: 0.10.26
+ */
diff --git a/libs/gst/base/gstbytewriter.h b/libs/gst/base/gstbytewriter.h
new file mode 100644
index 0000000000..63ed5a2026
--- /dev/null
+++ b/libs/gst/base/gstbytewriter.h
@@ -0,0 +1,167 @@
+/* GStreamer byte writer
+ *
+ * Copyright (C) 2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library 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.
+ */
+
+#ifndef __GST_BYTE_WRITER_H__
+#define __GST_BYTE_WRITER_H__
+
+#include <gst/gst.h>
+#include <gst/base/gstbytereader.h>
+
+G_BEGIN_DECLS
+
+#define GST_BYTE_WRITER(writer) ((GstByteWriter *) (writer))
+
+/**
+ * GstByteWriter:
+ * @parent: #GstByteReader parent
+ * @alloc_size: Allocation size of the data
+ * @fixed: If %TRUE no reallocations are allowed
+ * @owned: If %FALSE no reallocations are allowed and copies of data are returned
+ *
+ * A byte writer instance.
+ */
+typedef struct {
+  GstByteReader parent;
+
+  guint alloc_size;
+
+  gboolean fixed;
+  gboolean owned;
+} GstByteWriter;
+
+GstByteWriter * gst_byte_writer_new (void);
+GstByteWriter * gst_byte_writer_new_with_size (guint size, gboolean fixed);
+GstByteWriter * gst_byte_writer_new_with_data (guint8 *data, guint size, gboolean initialized);
+GstByteWriter * gst_byte_writer_new_with_buffer (GstBuffer *buffer, gboolean initialized);
+
+void gst_byte_writer_init (GstByteWriter *writer);
+void gst_byte_writer_init_with_size (GstByteWriter *writer, guint size, gboolean fixed);
+void gst_byte_writer_init_with_data (GstByteWriter *writer, guint8 *data, guint size, gboolean initialized);
+void gst_byte_writer_init_with_buffer (GstByteWriter *writer, GstBuffer *buffer, gboolean initialized);
+
+void gst_byte_writer_free (GstByteWriter *writer);
+guint8 * gst_byte_writer_free_and_get_data (GstByteWriter *writer);
+GstBuffer *gst_byte_writer_free_and_get_buffer (GstByteWriter *writer);
+
+void gst_byte_writer_reset (GstByteWriter *writer);
+guint8 * gst_byte_writer_reset_and_get_data (GstByteWriter *writer);
+GstBuffer *gst_byte_writer_reset_and_get_data_as_buffer (GstByteWriter *writer);
+
+/**
+ * gst_byte_writer_get_pos:
+ * @writer: #GstByteWriter instance
+ *
+ * Returns: The current position of the read/write cursor
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_set_pos:
+ * @writer: #GstByteWriter instance
+ * @pos: new position
+ *
+ * Sets the current read/write cursor of @writer. The new position
+ * can only be between 0 and the current size.
+ *
+ * Returns: %TRUE if the new position could be set
+ *
+ * Since: 0.10.26
+ */
+/**
+ * gst_byte_writer_get_size:
+ * @writer: #GstByteWriter instance
+ *
+ * Returns: The current, initialized size of the data
+ *
+ * Since: 0.10.26
+ */
+#ifdef _FOOL_GTK_DOC
+G_INLINE_FUNC guint gst_byte_writer_get_pos (const GstByteWriter *writer);
+G_INLINE_FUNC gboolean gst_byte_writer_set_pos (const GstByteWriter *writer, guint pos);
+G_INLINE_FUNC guint gst_byte_writer_get_size (const GstByteWriter *writer);
+#else
+static inline guint
+gst_byte_writer_get_pos (const GstByteWriter *writer)
+{
+  return gst_byte_reader_get_pos (GST_BYTE_READER (writer));
+}
+
+static inline gboolean
+gst_byte_writer_set_pos (const GstByteWriter *writer, guint pos)
+{
+  return gst_byte_reader_set_pos (GST_BYTE_READER (writer), pos);
+}
+
+static inline guint
+gst_byte_writer_get_size (const GstByteWriter *writer)
+{
+  return gst_byte_reader_get_size (GST_BYTE_READER (writer));
+}
+#endif
+
+guint gst_byte_writer_get_remaining (const GstByteWriter *writer);
+gboolean gst_byte_writer_ensure_free_space (GstByteWriter *writer, guint size);
+
+gboolean gst_byte_writer_put_uint8 (GstByteWriter *writer, guint8 val);
+gboolean gst_byte_writer_put_int8 (GstByteWriter *writer, gint8 val);
+gboolean gst_byte_writer_put_uint16_be (GstByteWriter *writer, guint16 val);
+gboolean gst_byte_writer_put_uint16_le (GstByteWriter *writer, guint16 val);
+gboolean gst_byte_writer_put_int16_be (GstByteWriter *writer, gint16 val);
+gboolean gst_byte_writer_put_int16_le (GstByteWriter *writer, gint16 val);
+gboolean gst_byte_writer_put_uint24_be (GstByteWriter *writer, guint32 val);
+gboolean gst_byte_writer_put_uint24_le (GstByteWriter *writer, guint32 val);
+gboolean gst_byte_writer_put_int24_be (GstByteWriter *writer, gint32 val);
+gboolean gst_byte_writer_put_int24_le (GstByteWriter *writer, gint32 val);
+gboolean gst_byte_writer_put_uint32_be (GstByteWriter *writer, guint32 val);
+gboolean gst_byte_writer_put_uint32_le (GstByteWriter *writer, guint32 val);
+gboolean gst_byte_writer_put_int32_be (GstByteWriter *writer, gint32 val);
+gboolean gst_byte_writer_put_int32_le (GstByteWriter *writer, gint32 val);
+gboolean gst_byte_writer_put_uint64_be (GstByteWriter *writer, guint64 val);
+gboolean gst_byte_writer_put_uint64_le (GstByteWriter *writer, guint64 val);
+gboolean gst_byte_writer_put_int64_be (GstByteWriter *writer, gint64 val);
+gboolean gst_byte_writer_put_int64_le (GstByteWriter *writer, gint64 val);
+
+gboolean gst_byte_writer_put_float_be (GstByteWriter *writer, gfloat val);
+gboolean gst_byte_writer_put_float_le (GstByteWriter *writer, gfloat val);
+gboolean gst_byte_writer_put_double_be (GstByteWriter *writer, gdouble val);
+gboolean gst_byte_writer_put_double_le (GstByteWriter *writer, gdouble val);
+
+gboolean gst_byte_writer_put_data (GstByteWriter *writer, const guint8 *data, guint size);
+gboolean gst_byte_writer_put_string_utf8 (GstByteWriter *writer, const gchar *data);
+gboolean gst_byte_writer_put_string_utf16 (GstByteWriter *writer, const guint16 *data);
+gboolean gst_byte_writer_put_string_utf32 (GstByteWriter *writer, const guint32 *data);
+
+/**
+ * gst_byte_writer_put_string:
+ * @writer: #GstByteWriter instance
+ * @data: Null terminated string
+ *
+ * Write a null-terminated string to @writer.
+ *
+ * Returns: %TRUE if the string could be written
+ *
+ * Since: 0.10.26
+ */
+#define gst_byte_writer_put_string(writer, data) \
+  gst_byte_writer_put_string_utf8(writer, data)
+
+G_END_DECLS
+
+#endif /* __GST_BYTE_WRITER_H__ */