gio/gzlibcompressor.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2009 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  *
  20  * Author: Alexander Larsson <alexl@redhat.com>
  21  */
  22
  23 #include "config.h"
  24
  25 #include "gzlibcompressor.h"
  26
  27 #include <errno.h>
  28 #include <zlib.h>
  29 #include <string.h>
  30
  31 #include "gfileinfo.h"
  32 #include "gioerror.h"
  33 #include "gioenums.h"
  34 #include "gioenumtypes.h"
  35 #include "glibintl.h"
  36
  37
  38 enum {
  39   PROP_0,
  40   PROP_FORMAT,
  41   PROP_LEVEL,
  42   PROP_FILE_INFO
  43 };
  44
  45 /**
  46  * SECTION:gzcompressor
  47  * @short_description: Zlib compressor
  48  * @include: gio/gio.h
  49  *
  50  * #GZlibCompressor is an implementation of #GConverter that
  51  * compresses data using zlib.
  52  */
  53
  54 static void g_zlib_compressor_iface_init          (GConverterIface *iface);
  55
  56 /**
  57  * GZlibCompressor:
  58  *
  59  * Zlib decompression
  60  */
  61 struct _GZlibCompressor
  62 {
  63   GObject parent_instance;
  64
  65   GZlibCompressorFormat format;
  66   int level;
  67   z_stream zstream;
  68   gz_header gzheader;
  69   GFileInfo *file_info;
  70 };
  71
  72 static void
  73 g_zlib_compressor_set_gzheader (GZlibCompressor *compressor)
  74 {
  75   const gchar *filename;
  76
  77   if (compressor->format != G_ZLIB_COMPRESSOR_FORMAT_GZIP ||
  78       compressor->file_info == NULL)
  79     return;
  80
  81   memset (&compressor->gzheader, 0, sizeof (gz_header));
  82   compressor->gzheader.os = 0x03; /* Unix */
  83
  84   filename = g_file_info_get_name (compressor->file_info);
  85   compressor->gzheader.name = (Bytef *) filename;
  86   compressor->gzheader.name_max = filename ? strlen (filename) + 1 : 0;
  87
  88   compressor->gzheader.time =
  89       (uLong) g_file_info_get_attribute_uint64 (compressor->file_info,
  90                                                 G_FILE_ATTRIBUTE_TIME_MODIFIED);
  91
  92   if (deflateSetHeader (&compressor->zstream, &compressor->gzheader) != Z_OK)
  93     g_warning ("unexpected zlib error: %s\n", compressor->zstream.msg);
  94 }
  95
  96 G_DEFINE_TYPE_WITH_CODE (GZlibCompressor, g_zlib_compressor, G_TYPE_OBJECT,
  97                          G_IMPLEMENT_INTERFACE (G_TYPE_CONVERTER,
  98                                                 g_zlib_compressor_iface_init))
  99
 100 static void
 101 g_zlib_compressor_finalize (GObject *object)
 102 {
 103   GZlibCompressor *compressor;
 104
 105   compressor = G_ZLIB_COMPRESSOR (object);
 106
 107   deflateEnd (&compressor->zstream);
 108
 109   if (compressor->file_info)
 110     g_object_unref (compressor->file_info);
 111
 112   G_OBJECT_CLASS (g_zlib_compressor_parent_class)->finalize (object);
 113 }
 114
 115
 116 static void
 117 g_zlib_compressor_set_property (GObject      *object,
 118                                   guint         prop_id,
 119                                   const GValue *value,
 120                                   GParamSpec   *pspec)
 121 {
 122   GZlibCompressor *compressor;
 123
 124   compressor = G_ZLIB_COMPRESSOR (object);
 125
 126   switch (prop_id)
 127     {
 128     case PROP_FORMAT:
 129       compressor->format = g_value_get_enum (value);
 130       break;
 131
 132     case PROP_LEVEL:
 133       compressor->level = g_value_get_int (value);
 134       break;
 135
 136     case PROP_FILE_INFO:
 137       g_zlib_compressor_set_file_info (compressor, g_value_get_object (value));
 138       break;
 139
 140     default:
 141       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 142       break;
 143     }
 144
 145 }
 146
 147 static void
 148 g_zlib_compressor_get_property (GObject    *object,
 149                                   guint       prop_id,
 150                                   GValue     *value,
 151                                   GParamSpec *pspec)
 152 {
 153   GZlibCompressor *compressor;
 154
 155   compressor = G_ZLIB_COMPRESSOR (object);
 156
 157   switch (prop_id)
 158     {
 159     case PROP_FORMAT:
 160       g_value_set_enum (value, compressor->format);
 161       break;
 162
 163     case PROP_LEVEL:
 164       g_value_set_int (value, compressor->level);
 165       break;
 166
 167     case PROP_FILE_INFO:
 168       g_value_set_object (value, compressor->file_info);
 169       break;
 170
 171     default:
 172       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 173       break;
 174     }
 175 }
 176
 177 static void
 178 g_zlib_compressor_init (GZlibCompressor *compressor)
 179 {
 180 }
 181
 182 static void
 183 g_zlib_compressor_constructed (GObject *object)
 184 {
 185   GZlibCompressor *compressor;
 186   int res;
 187
 188   compressor = G_ZLIB_COMPRESSOR (object);
 189
 190   if (compressor->format == G_ZLIB_COMPRESSOR_FORMAT_GZIP)
 191     {
 192       /* + 16 for gzip */
 193       res = deflateInit2 (&compressor->zstream,
 194                           compressor->level, Z_DEFLATED,
 195                           MAX_WBITS + 16, 8,
 196                           Z_DEFAULT_STRATEGY);
 197     }
 198   else if (compressor->format == G_ZLIB_COMPRESSOR_FORMAT_RAW)
 199     {
 200       /* negative wbits for raw */
 201       res = deflateInit2 (&compressor->zstream,
 202                           compressor->level, Z_DEFLATED,
 203                           -MAX_WBITS, 8,
 204                           Z_DEFAULT_STRATEGY);
 205     }
 206   else /* ZLIB */
 207     res = deflateInit (&compressor->zstream, compressor->level);
 208
 209   if (res == Z_MEM_ERROR )
 210     g_error ("GZlibCompressor: Not enough memory for zlib use");
 211
 212   if (res != Z_OK)
 213     g_warning ("unexpected zlib error: %s\n", compressor->zstream.msg);
 214
 215   g_zlib_compressor_set_gzheader (compressor);
 216 }
 217
 218 static void
 219 g_zlib_compressor_class_init (GZlibCompressorClass *klass)
 220 {
 221   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 222
 223   gobject_class->finalize = g_zlib_compressor_finalize;
 224   gobject_class->constructed = g_zlib_compressor_constructed;
 225   gobject_class->get_property = g_zlib_compressor_get_property;
 226   gobject_class->set_property = g_zlib_compressor_set_property;
 227
 228   g_object_class_install_property (gobject_class,
 229                                    PROP_FORMAT,
 230                                    g_param_spec_enum ("format",
 231                                                       P_("compression format"),
 232                                                       P_("The format of the compressed data"),
 233                                                       G_TYPE_ZLIB_COMPRESSOR_FORMAT,
 234                                                       G_ZLIB_COMPRESSOR_FORMAT_ZLIB,
 235                                                       G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
 236                                                       G_PARAM_STATIC_STRINGS));
 237   g_object_class_install_property (gobject_class,
 238                                    PROP_LEVEL,
 239                                    g_param_spec_int ("level",
 240                                                      P_("compression level"),
 241                                                      P_("The level of compression from 0 (no compression) to 9 (most compression), -1 for the default level"),
 242                                                      -1, 9,
 243                                                      -1,
 244                                                      G_PARAM_READWRITE |
 245                                                      G_PARAM_CONSTRUCT_ONLY |
 246                                                      G_PARAM_STATIC_STRINGS));
 247
 248   /**
 249    * GZlibCompressor:file-info:
 250    *
 251    * If set to a non-%NULL #GFileInfo object, and #GZlibCompressor:format is
 252    * %G_ZLIB_COMPRESSOR_FORMAT_GZIP, the compressor will write the file name
 253    * and modification time from the file info to the the GZIP header.
 254    *
 255    * Since: 2.26
 256    */
 257   g_object_class_install_property (gobject_class,
 258                                    PROP_FILE_INFO,
 259                                    g_param_spec_object ("file-info",
 260                                                        P_("file info"),
 261                                                        P_("File info"),
 262                                                        G_TYPE_FILE_INFO,
 263                                                        G_PARAM_READWRITE |
 264                                                        G_PARAM_STATIC_STRINGS));
 265 }
 266
 267 /**
 268  * g_zlib_compressor_new:
 269  * @format: The format to use for the compressed data
 270  * @level: compression level (0-9), -1 for default
 271  *
 272  * Creates a new #GZlibCompressor.
 273  *
 274  * Returns: a new #GZlibCompressor
 275  *
 276  * Since: 2.24
 277  **/
 278 GZlibCompressor *
 279 g_zlib_compressor_new (GZlibCompressorFormat format,
 280                        int level)
 281 {
 282   GZlibCompressor *compressor;
 283
 284   compressor = g_object_new (G_TYPE_ZLIB_COMPRESSOR,
 285                              "format", format,
 286                              "level", level,
 287                              NULL);
 288
 289   return compressor;
 290 }
 291
 292 /**
 293  * g_zlib_compressor_get_file_info:
 294  * @compressor: a #GZlibCompressor
 295  *
 296  * Returns the #GZlibCompressor:file-info property.
 297  *
 298  * Returns: (transfer none): a #GFileInfo, or %NULL
 299  *
 300  * Since: 2.26
 301  */
 302 GFileInfo *
 303 g_zlib_compressor_get_file_info (GZlibCompressor *compressor)
 304 {
 305   g_return_val_if_fail (G_IS_ZLIB_COMPRESSOR (compressor), NULL);
 306
 307   return compressor->file_info;
 308 }
 309
 310 /**
 311  * g_zlib_compressor_set_file_info:
 312  * @compressor: a #GZlibCompressor
 313  * @file_info: (allow-none): a #GFileInfo
 314  *
 315  * Sets @file_info in @compressor. If non-%NULL, and @compressor's
 316  * #GZlibCompressor:format property is %G_ZLIB_COMPRESSOR_FORMAT_GZIP,
 317  * it will be used to set the file name and modification time in
 318  * the GZIP header of the compressed data.
 319  *
 320  * Note: it is an error to call this function while a compression is in
 321  * progress; it may only be called immediately after creation of @compressor,
 322  * or after resetting it with g_converter_reset().
 323  *
 324  * Since: 2.26
 325  */
 326 void
 327 g_zlib_compressor_set_file_info (GZlibCompressor *compressor,
 328                                  GFileInfo       *file_info)
 329 {
 330   g_return_if_fail (G_IS_ZLIB_COMPRESSOR (compressor));
 331
 332   if (file_info == compressor->file_info)
 333     return;
 334
 335   if (compressor->file_info)
 336     g_object_unref (compressor->file_info);
 337   if (file_info)
 338     g_object_ref (file_info);
 339   compressor->file_info = file_info;
 340   g_object_notify (G_OBJECT (compressor), "file-info");
 341
 342   g_zlib_compressor_set_gzheader (compressor);
 343 }
 344
 345 static void
 346 g_zlib_compressor_reset (GConverter *converter)
 347 {
 348   GZlibCompressor *compressor = G_ZLIB_COMPRESSOR (converter);
 349   int res;
 350
 351   res = deflateReset (&compressor->zstream);
 352   if (res != Z_OK)
 353     g_warning ("unexpected zlib error: %s\n", compressor->zstream.msg);
 354
 355   /* deflateReset reset the header too, so re-set it */
 356   g_zlib_compressor_set_gzheader (compressor);
 357 }
 358
 359 static GConverterResult
 360 g_zlib_compressor_convert (GConverter *converter,
 361                            const void *inbuf,
 362                            gsize       inbuf_size,
 363                            void       *outbuf,
 364                            gsize       outbuf_size,
 365                            GConverterFlags flags,
 366                            gsize      *bytes_read,
 367                            gsize      *bytes_written,
 368                            GError    **error)
 369 {
 370   GZlibCompressor *compressor;
 371   int res;
 372   int flush;
 373
 374   compressor = G_ZLIB_COMPRESSOR (converter);
 375
 376   compressor->zstream.next_in = (void *)inbuf;
 377   compressor->zstream.avail_in = inbuf_size;
 378
 379   compressor->zstream.next_out = outbuf;
 380   compressor->zstream.avail_out = outbuf_size;
 381
 382   flush = Z_NO_FLUSH;
 383   if (flags & G_CONVERTER_INPUT_AT_END)
 384     flush = Z_FINISH;
 385   else if (flags & G_CONVERTER_FLUSH)
 386     flush = Z_SYNC_FLUSH;
 387
 388   res = deflate (&compressor->zstream, flush);
 389
 390   if (res == Z_MEM_ERROR)
 391     {
 392       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
 393                            _("Not enough memory"));
 394       return G_CONVERTER_ERROR;
 395     }
 396
 397     if (res == Z_STREAM_ERROR)
 398     {
 399       g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
 400                    _("Internal error: %s"), compressor->zstream.msg);
 401       return G_CONVERTER_ERROR;
 402     }
 403
 404     if (res == Z_BUF_ERROR)
 405       {
 406         if (flags & G_CONVERTER_FLUSH)
 407           return G_CONVERTER_FLUSHED;
 408
 409         /* We do have output space, so this should only happen if we
 410            have no input but need some */
 411
 412         g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PARTIAL_INPUT,
 413                              _("Need more input"));
 414         return G_CONVERTER_ERROR;
 415       }
 416
 417   if (res == Z_OK || res == Z_STREAM_END)
 418     {
 419       *bytes_read = inbuf_size - compressor->zstream.avail_in;
 420       *bytes_written = outbuf_size - compressor->zstream.avail_out;
 421
 422       if (res == Z_STREAM_END)
 423         return G_CONVERTER_FINISHED;
 424       return G_CONVERTER_CONVERTED;
 425     }
 426
 427   g_assert_not_reached ();
 428 }
 429
 430 static void
 431 g_zlib_compressor_iface_init (GConverterIface *iface)
 432 {
 433   iface->convert = g_zlib_compressor_convert;
 434   iface->reset = g_zlib_compressor_reset;
 435 }