gstreamer/libs/gst/base/gstbytewriter.c

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/* 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) \
{ \
guint8 *write_data; \
\
g_return_val_if_fail (writer != NULL, FALSE); \
\
if (G_UNLIKELY (!gst_byte_writer_ensure_free_space(writer, bits/8))) \
return FALSE; \
\
write_data = (guint8 *) writer->parent.data + writer->parent.byte; \
write_func (write_data, 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;
}
gboolean
gst_byte_writer_fill (GstByteWriter * writer, const guint8 value, guint size)
{
g_return_val_if_fail (writer != NULL, FALSE);
if (G_UNLIKELY (!gst_byte_writer_ensure_free_space (writer, size)))
return FALSE;
memset ((guint8 *) & writer->parent.data[writer->parent.byte], value, 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_float32_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: 0.10.27
*/
/**
* gst_byte_writer_put_float64_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: 0.10.27
*/
/**
* gst_byte_writer_put_float32_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: 0.10.27
*/
/**
* gst_byte_writer_put_float64_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: 0.10.27
*/
/**
* gst_byte_writer_put_string_utf8:
* @writer: #GstByteWriter instance
* @data: UTF8 string to write
*
* Writes a NUL-terminated UTF8 string to @writer (including the terminator).
*
* 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 NUL-terminated UTF16 string to @writer (including the terminator).
*
* 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 NUL-terminated UTF32 string to @writer (including the terminator).
*
* 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
*/
/**
* gst_byte_writer_fill:
* @writer: #GstByteWriter instance
* @value: Value to be writen
* @size: Number of bytes to be writen
*
* Writes @size bytes containing @value to @writer.
*
* Returns: %TRUE if the value could be written
*
* Since: 0.10.27
*/