text: /* 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, see <http://www.gnu.org/licenses/>.
   *
   * Author: Alexander Larsson <alexl@redhat.com>
   */
  
  #include "config.h"
  
  #include "gzlibdecompressor.h"
  
  #include <errno.h>
  #include <zlib.h>
  #include <string.h>
  
  #include "gfileinfo.h"
  #include "gioerror.h"
  #include "gioenums.h"
  #include "gioenumtypes.h"
  #include "glibintl.h"
  
  
  enum {
    PROP_0,
    PROP_FORMAT,
    PROP_FILE_INFO
  };
  
  /**
   * SECTION:gzdecompressor
   * @short_description: Zlib decompressor
   * @include: gio/gio.h
   *
   * #GZlibDecompressor is an implementation of #GConverter that
   * decompresses data compressed with zlib.
   */
  
  static void g_zlib_decompressor_iface_init          (GConverterIface *iface);
  
  typedef struct {
    gz_header gzheader;
    char filename[257];
    GFileInfo *file_info;
  } HeaderData;
  
  /**
   * GZlibDecompressor:
   *
   * Zlib decompression
   */
  struct _GZlibDecompressor
  {
    GObject parent_instance;
  
    GZlibCompressorFormat format;
    z_stream zstream;
    HeaderData *header_data;
  };
  
  static void
  g_zlib_decompressor_set_gzheader (GZlibDecompressor *decompressor)
  {
    /* On win32, these functions were not exported before 1.2.4 */
  #if !defined (G_OS_WIN32) || ZLIB_VERNUM >= 0x1240
    if (decompressor->format != G_ZLIB_COMPRESSOR_FORMAT_GZIP)
      return;
  
    if (decompressor->header_data != NULL)
      {
        if (decompressor->header_data->file_info)
          g_object_unref (decompressor->header_data->file_info);
  
        memset (decompressor->header_data, 0, sizeof (HeaderData));
      }
    else
      {
        decompressor->header_data = g_new0 (HeaderData, 1);
      }
  
    decompressor->header_data->gzheader.name = (Bytef*) &decompressor->header_data->filename;
    /* We keep one byte to guarantee the string is 0-terminated */
    decompressor->header_data->gzheader.name_max = 256;
  
    if (inflateGetHeader (&decompressor->zstream, &decompressor->header_data->gzheader) != Z_OK)
      g_warning ("unexpected zlib error: %s\n", decompressor->zstream.msg);
  #endif /* !G_OS_WIN32 || ZLIB >= 1.2.4 */
  }
  
  G_DEFINE_TYPE_WITH_CODE (GZlibDecompressor, g_zlib_decompressor, G_TYPE_OBJECT,
  			 G_IMPLEMENT_INTERFACE (G_TYPE_CONVERTER,
  						g_zlib_decompressor_iface_init))
  
  static void
  g_zlib_decompressor_finalize (GObject *object)
  {
    GZlibDecompressor *decompressor;
  
    decompressor = G_ZLIB_DECOMPRESSOR (object);
  
    inflateEnd (&decompressor->zstream);
  
    if (decompressor->header_data != NULL)
      {
        if (decompressor->header_data->file_info)
          g_object_unref (decompressor->header_data->file_info);
        g_free (decompressor->header_data);
      }
  
    G_OBJECT_CLASS (g_zlib_decompressor_parent_class)->finalize (object);
  }
  
  
  static void
  g_zlib_decompressor_set_property (GObject      *object,
  				  guint         prop_id,
  				  const GValue *value,
  				  GParamSpec   *pspec)
  {
    GZlibDecompressor *decompressor;
  
    decompressor = G_ZLIB_DECOMPRESSOR (object);
  
    switch (prop_id)
      {
      case PROP_FORMAT:
        decompressor->format = g_value_get_enum (value);
        break;
  
      default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
        break;
      }
  
  }
  
  static void
  g_zlib_decompressor_get_property (GObject    *object,
  				  guint       prop_id,
  				  GValue     *value,
  				  GParamSpec *pspec)
  {
    GZlibDecompressor *decompressor;
  
    decompressor = G_ZLIB_DECOMPRESSOR (object);
  
    switch (prop_id)
      {
      case PROP_FORMAT:
        g_value_set_enum (value, decompressor->format);
        break;
  
      case PROP_FILE_INFO:
        if (decompressor->header_data)
          g_value_set_object (value, decompressor->header_data->file_info);
        else
          g_value_set_object (value, NULL);
        break;
  
      default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
        break;
      }
  }
  
  static void
  g_zlib_decompressor_init (GZlibDecompressor *decompressor)
  {
  }
  
  static void
  g_zlib_decompressor_constructed (GObject *object)
  {
    GZlibDecompressor *decompressor;
    int res;
  
    decompressor = G_ZLIB_DECOMPRESSOR (object);
  
    if (decompressor->format == G_ZLIB_COMPRESSOR_FORMAT_GZIP)
      {
        /* + 16 for gzip */
        res = inflateInit2 (&decompressor->zstream, MAX_WBITS + 16);
      }
    else if (decompressor->format == G_ZLIB_COMPRESSOR_FORMAT_RAW)
      {
        /* Negative for raw */
        res = inflateInit2 (&decompressor->zstream, -MAX_WBITS);
      }
    else /* ZLIB */
      res = inflateInit (&decompressor->zstream);
  
    if (res == Z_MEM_ERROR )
      g_error ("GZlibDecompressor: Not enough memory for zlib use");
  
    if (res != Z_OK)
      g_warning ("unexpected zlib error: %s\n", decompressor->zstream.msg);
  
    g_zlib_decompressor_set_gzheader (decompressor);
  }
  
  static void
  g_zlib_decompressor_class_init (GZlibDecompressorClass *klass)
  {
    GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  
    gobject_class->finalize = g_zlib_decompressor_finalize;
    gobject_class->constructed = g_zlib_decompressor_constructed;
    gobject_class->get_property = g_zlib_decompressor_get_property;
    gobject_class->set_property = g_zlib_decompressor_set_property;
  
    g_object_class_install_property (gobject_class,
  				   PROP_FORMAT,
  				   g_param_spec_enum ("format",
  						      P_("compression format"),
  						      P_("The format of the compressed data"),
  						      G_TYPE_ZLIB_COMPRESSOR_FORMAT,
  						      G_ZLIB_COMPRESSOR_FORMAT_ZLIB,
  						      G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
  						      G_PARAM_STATIC_STRINGS));
  
    /**
     * GZlibDecompressor:file-info:
     *
     * A #GFileInfo containing the information found in the GZIP header
     * of the data stream processed, or %NULL if the header was not yet
     * fully processed, is not present at all, or the compressor's
     * #GZlibDecompressor:format property is not %G_ZLIB_COMPRESSOR_FORMAT_GZIP.
     *
     * Since: 2.26
     */
    g_object_class_install_property (gobject_class,
                                     PROP_FILE_INFO,
                                     g_param_spec_object ("file-info",
                                                         P_("file info"),
                                                         P_("File info"),
                                                         G_TYPE_FILE_INFO,
                                                         G_PARAM_READABLE |
                                                         G_PARAM_STATIC_STRINGS));
  }
  
  /**
   * g_zlib_decompressor_new:
   * @format: The format to use for the compressed data
   *
   * Creates a new #GZlibDecompressor.
   *
   * Returns: a new #GZlibDecompressor
   *
   * Since: 2.24
   **/
  GZlibDecompressor *
  g_zlib_decompressor_new (GZlibCompressorFormat format)
  {
    GZlibDecompressor *decompressor;
  
    decompressor = g_object_new (G_TYPE_ZLIB_DECOMPRESSOR,
  			       "format", format,
  			       NULL);
  
    return decompressor;
  }
  
  /**
   * g_zlib_decompressor_get_file_info:
   * @decompressor: a #GZlibDecompressor
   *
   * Retrieves the #GFileInfo constructed from the GZIP header data
   * of compressed data processed by @compressor, or %NULL if @decompressor's
   * #GZlibDecompressor:format property is not %G_ZLIB_COMPRESSOR_FORMAT_GZIP,
   * or the header data was not fully processed yet, or it not present in the
   * data stream at all.
   *
   * Returns: (transfer none): a #GFileInfo, or %NULL
   *
   * Since: 2.26
   */
  GFileInfo *
  g_zlib_decompressor_get_file_info (GZlibDecompressor *decompressor)
  {
    g_return_val_if_fail (G_IS_ZLIB_DECOMPRESSOR (decompressor), NULL);
  
    if (decompressor->header_data)
      return decompressor->header_data->file_info;
  
    return NULL;
  }
  
  static void
  g_zlib_decompressor_reset (GConverter *converter)
  {
    GZlibDecompressor *decompressor = G_ZLIB_DECOMPRESSOR (converter);
    int res;
  
    res = inflateReset (&decompressor->zstream);
    if (res != Z_OK)
      g_warning ("unexpected zlib error: %s\n", decompressor->zstream.msg);
  
    g_zlib_decompressor_set_gzheader (decompressor);
  }
  
  static GConverterResult
  g_zlib_decompressor_convert (GConverter *converter,
  			     const void *inbuf,
  			     gsize       inbuf_size,
  			     void       *outbuf,
  			     gsize       outbuf_size,
  			     GConverterFlags flags,
  			     gsize      *bytes_read,
  			     gsize      *bytes_written,
  			     GError    **error)
  {
    GZlibDecompressor *decompressor;
    int res;
  
    decompressor = G_ZLIB_DECOMPRESSOR (converter);
  
    decompressor->zstream.next_in = (void *)inbuf;
    decompressor->zstream.avail_in = inbuf_size;
  
    decompressor->zstream.next_out = outbuf;
    decompressor->zstream.avail_out = outbuf_size;
  
    res = inflate (&decompressor->zstream, Z_NO_FLUSH);
  
    if (res == Z_DATA_ERROR || res == Z_NEED_DICT)
      {
        g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_INVALID_DATA,
  			   _("Invalid compressed data"));
        return G_CONVERTER_ERROR;
      }
  
    if (res == Z_MEM_ERROR)
      {
        g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
  			   _("Not enough memory"));
        return G_CONVERTER_ERROR;
      }
  
      if (res == Z_STREAM_ERROR)
      {
        g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
  		   _("Internal error: %s"), decompressor->zstream.msg);
        return G_CONVERTER_ERROR;
      }
  
      if (res == Z_BUF_ERROR)
        {
  	if (flags & G_CONVERTER_FLUSH)
  	  return G_CONVERTER_FLUSHED;
  
  	/* Z_FINISH not set, so this means no progress could be made */
  	/* We do have output space, so this should only happen if we
  	   have no input but need some */
  
  	g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PARTIAL_INPUT,
  			     _("Need more input"));
  	return G_CONVERTER_ERROR;
        }
  
    g_assert (res == Z_OK || res == Z_STREAM_END);
  
    *bytes_read = inbuf_size - decompressor->zstream.avail_in;
    *bytes_written = outbuf_size - decompressor->zstream.avail_out;
  
  #if !defined (G_OS_WIN32) || ZLIB_VERNUM >= 0x1240
    if (decompressor->header_data != NULL &&
        decompressor->header_data->gzheader.done == 1)
      {
        HeaderData *data = decompressor->header_data;
  
        /* So we don't notify again */
        data->gzheader.done = 2;
  
        data->file_info = g_file_info_new ();
        g_file_info_set_attribute_uint64 (data->file_info,
                                          G_FILE_ATTRIBUTE_TIME_MODIFIED,
                                          data->gzheader.time);
        g_file_info_set_attribute_uint32 (data->file_info,
                                          G_FILE_ATTRIBUTE_TIME_MODIFIED_USEC,
                                          0);
  
        if (data->filename[0] != '\0')
          g_file_info_set_attribute_byte_string (data->file_info,
                                                 G_FILE_ATTRIBUTE_STANDARD_NAME,
                                                 data->filename);
  
        g_object_notify (G_OBJECT (decompressor), "file-info");
      }
  #endif /* !G_OS_WIN32 || ZLIB >= 1.2.4 */
  
    if (res == Z_STREAM_END)
      return G_CONVERTER_FINISHED;
    return G_CONVERTER_CONVERTED;
  }
  
  static void
  g_zlib_decompressor_iface_init (GConverterIface *iface)
  {
    iface->convert = g_zlib_decompressor_convert;
    iface->reset = g_zlib_decompressor_reset;
  }
  