gio/gconverter.c - third_party/glib - Git at Google

 /* GIO - GLib Input, Output and Streaming Library
  *
  * Copyright (C) 2009 Red Hat, Inc.
  *
  * SPDX-License-Identifier: LGPL-2.1-or-later
  *
  * 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, see <http://www.gnu.org/licenses/>.
  *
  * Author: Alexander Larsson <alexl@redhat.com>
  */

 #include "config.h"
 #include "gconverter.h"
 #include "glibintl.h"


 /**
  * GConverter:
  *
  * `GConverter` is an interface for streaming conversions.
  *
  * `GConverter` is implemented by objects that convert
  * binary data in various ways. The conversion can be
  * stateful and may fail at any place.
  *
  * Some example conversions are: character set conversion,
  * compression, decompression and regular expression
  * replace.
  *
  * Since: 2.24
  */


 typedef GConverterIface GConverterInterface;
 G_DEFINE_INTERFACE (GConverter, g_converter, G_TYPE_OBJECT)

 static void
 g_converter_default_init (GConverterInterface *iface)
 {
 }

 /**
  * g_converter_convert:
  * @converter: a #GConverter.
  * @inbuf: (array length=inbuf_size) (element-type guint8): the buffer
  *         containing the data to convert.
  * @inbuf_size: the number of bytes in @inbuf
  * @outbuf: (element-type guint8) (array length=outbuf_size) (not nullable): a
  *    buffer to write converted data in.
  * @outbuf_size: the number of bytes in @outbuf, must be at least one
  * @flags: a #GConverterFlags controlling the conversion details
  * @bytes_read: (out) (not nullable): will be set to the number of bytes read
  *    from @inbuf on success
  * @bytes_written: (out) (not nullable): will be set to the number of bytes
  *    written to @outbuf on success
  * @error: location to store the error occurring, or %NULL to ignore
  *
  * This is the main operation used when converting data. It is to be called
  * multiple times in a loop, and each time it will do some work, i.e.
  * producing some output (in @outbuf) or consuming some input (from @inbuf) or
  * both. If its not possible to do any work an error is returned.
  *
  * Note that a single call may not consume all input (or any input at all).
  * Also a call may produce output even if given no input, due to state stored
  * in the converter producing output.
  *
  * If any data was either produced or consumed, and then an error happens, then
  * only the successful conversion is reported and the error is returned on the
  * next call.
  *
  * A full conversion loop involves calling this method repeatedly, each time
  * giving it new input and space output space. When there is no more input
  * data after the data in @inbuf, the flag %G_CONVERTER_INPUT_AT_END must be set.
  * The loop will be (unless some error happens) returning %G_CONVERTER_CONVERTED
  * each time until all data is consumed and all output is produced, then
  * %G_CONVERTER_FINISHED is returned instead. Note, that %G_CONVERTER_FINISHED
  * may be returned even if %G_CONVERTER_INPUT_AT_END is not set, for instance
  * in a decompression converter where the end of data is detectable from the
  * data (and there might even be other data after the end of the compressed data).
  *
  * When some data has successfully been converted @bytes_read and is set to
  * the number of bytes read from @inbuf, and @bytes_written is set to indicate
  * how many bytes was written to @outbuf. If there are more data to output
  * or consume (i.e. unless the %G_CONVERTER_INPUT_AT_END is specified) then
  * %G_CONVERTER_CONVERTED is returned, and if no more data is to be output
  * then %G_CONVERTER_FINISHED is returned.
  *
  * On error %G_CONVERTER_ERROR is returned and @error is set accordingly.
  * Some errors need special handling:
  *
  * %G_IO_ERROR_NO_SPACE is returned if there is not enough space
  * to write the resulting converted data, the application should
  * call the function again with a larger @outbuf to continue.
  *
  * %G_IO_ERROR_PARTIAL_INPUT is returned if there is not enough
  * input to fully determine what the conversion should produce,
  * and the %G_CONVERTER_INPUT_AT_END flag is not set. This happens for
  * example with an incomplete multibyte sequence when converting text,
  * or when a regexp matches up to the end of the input (and may match
  * further input). It may also happen when @inbuf_size is zero and
  * there is no more data to produce.
  *
  * When this happens the application should read more input and then
  * call the function again. If further input shows that there is no
  * more data call the function again with the same data but with
  * the %G_CONVERTER_INPUT_AT_END flag set. This may cause the conversion
  * to finish as e.g. in the regexp match case (or, to fail again with
  * %G_IO_ERROR_PARTIAL_INPUT in e.g. a charset conversion where the
  * input is actually partial).
  *
  * After g_converter_convert() has returned %G_CONVERTER_FINISHED the
  * converter object is in an invalid state where its not allowed
  * to call g_converter_convert() anymore. At this time you can only
  * free the object or call g_converter_reset() to reset it to the
  * initial state.
  *
  * If the flag %G_CONVERTER_FLUSH is set then conversion is modified
  * to try to write out all internal state to the output. The application
  * has to call the function multiple times with the flag set, and when
  * the available input has been consumed and all internal state has
  * been produced then %G_CONVERTER_FLUSHED (or %G_CONVERTER_FINISHED if
  * really at the end) is returned instead of %G_CONVERTER_CONVERTED.
  * This is somewhat similar to what happens at the end of the input stream,
  * but done in the middle of the data.
  *
  * This has different meanings for different conversions. For instance
  * in a compression converter it would mean that we flush all the
  * compression state into output such that if you uncompress the
  * compressed data you get back all the input data. Doing this may
  * make the final file larger due to padding though. Another example
  * is a regexp conversion, where if you at the end of the flushed data
  * have a match, but there is also a potential longer match. In the
  * non-flushed case we would ask for more input, but when flushing we
  * treat this as the end of input and do the match.
  *
  * Flushing is not always possible (like if a charset converter flushes
  * at a partial multibyte sequence). Converters are supposed to try
  * to produce as much output as possible and then return an error
  * (typically %G_IO_ERROR_PARTIAL_INPUT).
  *
  * Returns: a #GConverterResult, %G_CONVERTER_ERROR on error.
  *
  * Since: 2.24
  **/
 GConverterResult
 g_converter_convert (GConverter *converter,
 		     const void *inbuf,
 		     gsize       inbuf_size,
 		     void       *outbuf,
 		     gsize       outbuf_size,
 		     GConverterFlags flags,
 		     gsize      *bytes_read,
 		     gsize      *bytes_written,
 		     GError    **error)
 {
   GConverterIface *iface;

   g_return_val_if_fail (G_IS_CONVERTER (converter), G_CONVERTER_ERROR);
   g_return_val_if_fail (inbuf != NULL || inbuf_size == 0, G_CONVERTER_ERROR);
   g_return_val_if_fail (outbuf != NULL, G_CONVERTER_ERROR);
   g_return_val_if_fail (outbuf_size > 0, G_CONVERTER_ERROR);
   g_return_val_if_fail (bytes_read != NULL, G_CONVERTER_ERROR);
   g_return_val_if_fail (bytes_written != NULL, G_CONVERTER_ERROR);
   g_return_val_if_fail (error == NULL || *error == NULL, G_CONVERTER_ERROR);

   *bytes_read = 0;
   *bytes_written = 0;

   iface = G_CONVERTER_GET_IFACE (converter);

   return (* iface->convert) (converter,
 			     inbuf, inbuf_size,
 			     outbuf, outbuf_size,
 			     flags,
 			     bytes_read, bytes_written, error);
 }

 /**
  * g_converter_reset:
  * @converter: a #GConverter.
  *
  * Resets all internal state in the converter, making it behave
  * as if it was just created. If the converter has any internal
  * state that would produce output then that output is lost.
  *
  * Since: 2.24
  **/
 void
 g_converter_reset (GConverter *converter)
 {
   GConverterIface *iface;

   g_return_if_fail (G_IS_CONVERTER (converter));

   iface = G_CONVERTER_GET_IFACE (converter);

   (* iface->reset) (converter);
 }
	/* GIO - GLib Input, Output and Streaming Library
	*
	* Copyright (C) 2009 Red Hat, Inc.
	*
	* SPDX-License-Identifier: LGPL-2.1-or-later
	*
	* 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, see <http://www.gnu.org/licenses/>.
	*
	* Author: Alexander Larsson <alexl@redhat.com>
	*/

	#include "config.h"
	#include "gconverter.h"
	#include "glibintl.h"


	/**
	* GConverter:
	*
	* `GConverter` is an interface for streaming conversions.
	*
	* `GConverter` is implemented by objects that convert
	* binary data in various ways. The conversion can be
	* stateful and may fail at any place.
	*
	* Some example conversions are: character set conversion,
	* compression, decompression and regular expression
	* replace.
	*
	* Since: 2.24
	*/


	typedef GConverterIface GConverterInterface;
	G_DEFINE_INTERFACE (GConverter, g_converter, G_TYPE_OBJECT)

	static void
	g_converter_default_init (GConverterInterface *iface)
	{
	}

	/**
	* g_converter_convert:
	* @converter: a #GConverter.
	* @inbuf: (array length=inbuf_size) (element-type guint8): the buffer
	* containing the data to convert.
	* @inbuf_size: the number of bytes in @inbuf
	* @outbuf: (element-type guint8) (array length=outbuf_size) (not nullable): a
	* buffer to write converted data in.
	* @outbuf_size: the number of bytes in @outbuf, must be at least one
	* @flags: a #GConverterFlags controlling the conversion details
	* @bytes_read: (out) (not nullable): will be set to the number of bytes read
	* from @inbuf on success
	* @bytes_written: (out) (not nullable): will be set to the number of bytes
	* written to @outbuf on success
	* @error: location to store the error occurring, or %NULL to ignore
	*
	* This is the main operation used when converting data. It is to be called
	* multiple times in a loop, and each time it will do some work, i.e.
	* producing some output (in @outbuf) or consuming some input (from @inbuf) or
	* both. If its not possible to do any work an error is returned.
	*
	* Note that a single call may not consume all input (or any input at all).
	* Also a call may produce output even if given no input, due to state stored
	* in the converter producing output.
	*
	* If any data was either produced or consumed, and then an error happens, then
	* only the successful conversion is reported and the error is returned on the
	* next call.
	*
	* A full conversion loop involves calling this method repeatedly, each time
	* giving it new input and space output space. When there is no more input
	* data after the data in @inbuf, the flag %G_CONVERTER_INPUT_AT_END must be set.
	* The loop will be (unless some error happens) returning %G_CONVERTER_CONVERTED
	* each time until all data is consumed and all output is produced, then
	* %G_CONVERTER_FINISHED is returned instead. Note, that %G_CONVERTER_FINISHED
	* may be returned even if %G_CONVERTER_INPUT_AT_END is not set, for instance
	* in a decompression converter where the end of data is detectable from the
	* data (and there might even be other data after the end of the compressed data).
	*
	* When some data has successfully been converted @bytes_read and is set to
	* the number of bytes read from @inbuf, and @bytes_written is set to indicate
	* how many bytes was written to @outbuf. If there are more data to output
	* or consume (i.e. unless the %G_CONVERTER_INPUT_AT_END is specified) then
	* %G_CONVERTER_CONVERTED is returned, and if no more data is to be output
	* then %G_CONVERTER_FINISHED is returned.
	*
	* On error %G_CONVERTER_ERROR is returned and @error is set accordingly.
	* Some errors need special handling:
	*
	* %G_IO_ERROR_NO_SPACE is returned if there is not enough space
	* to write the resulting converted data, the application should
	* call the function again with a larger @outbuf to continue.
	*
	* %G_IO_ERROR_PARTIAL_INPUT is returned if there is not enough
	* input to fully determine what the conversion should produce,
	* and the %G_CONVERTER_INPUT_AT_END flag is not set. This happens for
	* example with an incomplete multibyte sequence when converting text,
	* or when a regexp matches up to the end of the input (and may match
	* further input). It may also happen when @inbuf_size is zero and
	* there is no more data to produce.
	*
	* When this happens the application should read more input and then
	* call the function again. If further input shows that there is no
	* more data call the function again with the same data but with
	* the %G_CONVERTER_INPUT_AT_END flag set. This may cause the conversion
	* to finish as e.g. in the regexp match case (or, to fail again with
	* %G_IO_ERROR_PARTIAL_INPUT in e.g. a charset conversion where the
	* input is actually partial).
	*
	* After g_converter_convert() has returned %G_CONVERTER_FINISHED the
	* converter object is in an invalid state where its not allowed
	* to call g_converter_convert() anymore. At this time you can only
	* free the object or call g_converter_reset() to reset it to the
	* initial state.
	*
	* If the flag %G_CONVERTER_FLUSH is set then conversion is modified
	* to try to write out all internal state to the output. The application
	* has to call the function multiple times with the flag set, and when
	* the available input has been consumed and all internal state has
	* been produced then %G_CONVERTER_FLUSHED (or %G_CONVERTER_FINISHED if
	* really at the end) is returned instead of %G_CONVERTER_CONVERTED.
	* This is somewhat similar to what happens at the end of the input stream,
	* but done in the middle of the data.
	*
	* This has different meanings for different conversions. For instance
	* in a compression converter it would mean that we flush all the
	* compression state into output such that if you uncompress the
	* compressed data you get back all the input data. Doing this may
	* make the final file larger due to padding though. Another example
	* is a regexp conversion, where if you at the end of the flushed data
	* have a match, but there is also a potential longer match. In the
	* non-flushed case we would ask for more input, but when flushing we
	* treat this as the end of input and do the match.
	*
	* Flushing is not always possible (like if a charset converter flushes
	* at a partial multibyte sequence). Converters are supposed to try
	* to produce as much output as possible and then return an error
	* (typically %G_IO_ERROR_PARTIAL_INPUT).
	*
	* Returns: a #GConverterResult, %G_CONVERTER_ERROR on error.
	*
	* Since: 2.24
	**/
	GConverterResult
	g_converter_convert (GConverter *converter,
	const void *inbuf,
	gsize inbuf_size,
	void *outbuf,
	gsize outbuf_size,
	GConverterFlags flags,
	gsize *bytes_read,
	gsize *bytes_written,
	GError **error)
	{
	GConverterIface *iface;

	g_return_val_if_fail (G_IS_CONVERTER (converter), G_CONVERTER_ERROR);
	g_return_val_if_fail (inbuf != NULL \|\| inbuf_size == 0, G_CONVERTER_ERROR);
	g_return_val_if_fail (outbuf != NULL, G_CONVERTER_ERROR);
	g_return_val_if_fail (outbuf_size > 0, G_CONVERTER_ERROR);
	g_return_val_if_fail (bytes_read != NULL, G_CONVERTER_ERROR);
	g_return_val_if_fail (bytes_written != NULL, G_CONVERTER_ERROR);
	g_return_val_if_fail (error == NULL \|\| *error == NULL, G_CONVERTER_ERROR);

	*bytes_read = 0;
	*bytes_written = 0;

	iface = G_CONVERTER_GET_IFACE (converter);

	return (* iface->convert) (converter,
	inbuf, inbuf_size,
	outbuf, outbuf_size,
	flags,
	bytes_read, bytes_written, error);
	}

	/**
	* g_converter_reset:
	* @converter: a #GConverter.
	*
	* Resets all internal state in the converter, making it behave
	* as if it was just created. If the converter has any internal
	* state that would produce output then that output is lost.
	*
	* Since: 2.24
	**/
	void
	g_converter_reset (GConverter *converter)
	{
	GConverterIface *iface;

	g_return_if_fail (G_IS_CONVERTER (converter));

	iface = G_CONVERTER_GET_IFACE (converter);

	(* iface->reset) (converter);
	}