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 2.1 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, see <http://www.gnu.org/licenses/>.
  17  *
  18  * Author: Alexander Larsson <alexl@redhat.com>
  19  */
  20
  21 #include "config.h"
  22
  23 #include "gzlibcompressor.h"
  24
  25 #include <errno.h>
  26 #include <zlib.h>
  27 #include <string.h>
  28
  29 #include "gfileinfo.h"
  30 #include "gioerror.h"
  31 #include "gioenums.h"
  32 #include "gioenumtypes.h"
  33 #include "glibintl.h"
  34
  35
  36 enum {
  37   PROP_0,
  38   PROP_FORMAT,
  39   PROP_LEVEL,
  40   PROP_FILE_INFO
  41 };
  42
  43 /**
  44  * SECTION:gzcompressor
  45  * @short_description: Zlib compressor
  46  * @include: gio/gio.h
  47  *
  48  * #GZlibCompressor is an implementation of #GConverter that
  49  * compresses data using zlib.
  50  */
  51
  52 static void g_zlib_compressor_iface_init          (GConverterIface *iface);
  53
  54 /**
  55  * GZlibCompressor:
  56  *
  57  * Zlib decompression
  58  */
  59 struct _GZlibCompressor
  60 {
  61   GObject parent_instance;
  62
  63   GZlibCompressorFormat format;
  64   int level;
  65   z_stream zstream;
  66   gz_header gzheader;
  67   GFileInfo *file_info;
  68 };
  69
  70 static void
  71 g_zlib_compressor_set_gzheader (GZlibCompressor *compressor)
  72 {
  73   /* On win32, these functions were not exported before 1.2.4 */
  74 #if !defined (G_OS_WIN32) || ZLIB_VERNUM >= 0x1240
  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", compressor->zstream.msg);
  94 #endif /* !G_OS_WIN32 || ZLIB >= 1.2.4 */
  95 }
  96
  97 G_DEFINE_TYPE_WITH_CODE (GZlibCompressor, g_zlib_compressor, G_TYPE_OBJECT,
  98                          G_IMPLEMENT_INTERFACE (G_TYPE_CONVERTER,
  99                                                 g_zlib_compressor_iface_init))
 100
 101 static void
 102 g_zlib_compressor_finalize (GObject *object)
 103 {
 104   GZlibCompressor *compressor;
 105
 106   compressor = G_ZLIB_COMPRESSOR (object);
 107
 108   deflateEnd (&compressor->zstream);
 109
 110   if (compressor->file_info)
 111     g_object_unref (compressor->file_info);
 112
 113   G_OBJECT_CLASS (g_zlib_compressor_parent_class)->finalize (object);
 114 }
 115
 116
 117 static void
 118 g_zlib_compressor_set_property (GObject      *object,
 119                                   guint         prop_id,
 120                                   const GValue *value,
 121                                   GParamSpec   *pspec)
 122 {
 123   GZlibCompressor *compressor;
 124
 125   compressor = G_ZLIB_COMPRESSOR (object);
 126
 127   switch (prop_id)
 128     {
 129     case PROP_FORMAT:
 130       compressor->format = g_value_get_enum (value);
 131       break;
 132
 133     case PROP_LEVEL:
 134       compressor->level = g_value_get_int (value);
 135       break;
 136
 137     case PROP_FILE_INFO:
 138       g_zlib_compressor_set_file_info (compressor, g_value_get_object (value));
 139       break;
 140
 141     default:
 142       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 143       break;
 144     }
 145
 146 }
 147
 148 static void
 149 g_zlib_compressor_get_property (GObject    *object,
 150                                   guint       prop_id,
 151                                   GValue     *value,
 152                                   GParamSpec *pspec)
 153 {
 154   GZlibCompressor *compressor;
 155
 156   compressor = G_ZLIB_COMPRESSOR (object);
 157
 158   switch (prop_id)
 159     {
 160     case PROP_FORMAT:
 161       g_value_set_enum (value, compressor->format);
 162       break;
 163
 164     case PROP_LEVEL:
 165       g_value_set_int (value, compressor->level);
 166       break;
 167
 168     case PROP_FILE_INFO:
 169       g_value_set_object (value, compressor->file_info);
 170       break;
 171
 172     default:
 173       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 174       break;
 175     }
 176 }
 177
 178 static void
 179 g_zlib_compressor_init (GZlibCompressor *compressor)
 180 {
 181 }
 182
 183 static void
 184 g_zlib_compressor_constructed (GObject *object)
 185 {
 186   GZlibCompressor *compressor;
 187   int res;
 188
 189   compressor = G_ZLIB_COMPRESSOR (object);
 190
 191   if (compressor->format == G_ZLIB_COMPRESSOR_FORMAT_GZIP)
 192     {
 193       /* + 16 for gzip */
 194       res = deflateInit2 (&compressor->zstream,
 195                           compressor->level, Z_DEFLATED,
 196                           MAX_WBITS + 16, 8,
 197                           Z_DEFAULT_STRATEGY);
 198     }
 199   else if (compressor->format == G_ZLIB_COMPRESSOR_FORMAT_RAW)
 200     {
 201       /* negative wbits for raw */
 202       res = deflateInit2 (&compressor->zstream,
 203                           compressor->level, Z_DEFLATED,
 204                           -MAX_WBITS, 8,
 205                           Z_DEFAULT_STRATEGY);
 206     }
 207   else /* ZLIB */
 208     res = deflateInit (&compressor->zstream, compressor->level);
 209
 210   if (res == Z_MEM_ERROR )
 211     g_error ("GZlibCompressor: Not enough memory for zlib use");
 212
 213   if (res != Z_OK)
 214     g_warning ("unexpected zlib error: %s", compressor->zstream.msg);
 215
 216   g_zlib_compressor_set_gzheader (compressor);
 217 }
 218
 219 static void
 220 g_zlib_compressor_class_init (GZlibCompressorClass *klass)
 221 {
 222   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 223
 224   gobject_class->finalize = g_zlib_compressor_finalize;
 225   gobject_class->constructed = g_zlib_compressor_constructed;
 226   gobject_class->get_property = g_zlib_compressor_get_property;
 227   gobject_class->set_property = g_zlib_compressor_set_property;
 228
 229   g_object_class_install_property (gobject_class,
 230                                    PROP_FORMAT,
 231                                    g_param_spec_enum ("format",
 232                                                       P_("compression format"),
 233                                                       P_("The format of the compressed data"),
 234                                                       G_TYPE_ZLIB_COMPRESSOR_FORMAT,
 235                                                       G_ZLIB_COMPRESSOR_FORMAT_ZLIB,
 236                                                       G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
 237                                                       G_PARAM_STATIC_STRINGS));
 238   g_object_class_install_property (gobject_class,
 239                                    PROP_LEVEL,
 240                                    g_param_spec_int ("level",
 241                                                      P_("compression level"),
 242                                                      P_("The level of compression from 0 (no compression) to 9 (most compression), -1 for the default level"),
 243                                                      -1, 9,
 244                                                      -1,
 245                                                      G_PARAM_READWRITE |
 246                                                      G_PARAM_CONSTRUCT_ONLY |
 247                                                      G_PARAM_STATIC_STRINGS));
 248
 249   /**
 250    * GZlibCompressor:file-info:
 251    *
 252    * If set to a non-%NULL #GFileInfo object, and #GZlibCompressor:format is
 253    * %G_ZLIB_COMPRESSOR_FORMAT_GZIP, the compressor will write the file name
 254    * and modification time from the file info to the GZIP header.
 255    *
 256    * Since: 2.26
 257    */
 258   g_object_class_install_property (gobject_class,
 259                                    PROP_FILE_INFO,
 260                                    g_param_spec_object ("file-info",
 261                                                        P_("file info"),
 262                                                        P_("File info"),
 263                                                        G_TYPE_FILE_INFO,
 264                                                        G_PARAM_READWRITE |
 265                                                        G_PARAM_STATIC_STRINGS));
 266 }
 267
 268 /**
 269  * g_zlib_compressor_new:
 270  * @format: The format to use for the compressed data
 271  * @level: compression level (0-9), -1 for default
 272  *
 273  * Creates a new #GZlibCompressor.
 274  *
 275  * Returns: a new #GZlibCompressor
 276  *
 277  * Since: 2.24
 278  **/
 279 GZlibCompressor *
 280 g_zlib_compressor_new (GZlibCompressorFormat format,
 281                        int level)
 282 {
 283   GZlibCompressor *compressor;
 284
 285   compressor = g_object_new (G_TYPE_ZLIB_COMPRESSOR,
 286                              "format", format,
 287                              "level", level,
 288                              NULL);
 289
 290   return compressor;
 291 }
 292
 293 /**
 294  * g_zlib_compressor_get_file_info:
 295  * @compressor: a #GZlibCompressor
 296  *
 297  * Returns the #GZlibCompressor:file-info property.
 298  *
 299  * Returns: (transfer none): a #GFileInfo, or %NULL
 300  *
 301  * Since: 2.26
 302  */
 303 GFileInfo *
 304 g_zlib_compressor_get_file_info (GZlibCompressor *compressor)
 305 {
 306   g_return_val_if_fail (G_IS_ZLIB_COMPRESSOR (compressor), NULL);
 307
 308   return compressor->file_info;
 309 }
 310
 311 /**
 312  * g_zlib_compressor_set_file_info:
 313  * @compressor: a #GZlibCompressor
 314  * @file_info: (nullable): a #GFileInfo
 315  *
 316  * Sets @file_info in @compressor. If non-%NULL, and @compressor's
 317  * #GZlibCompressor:format property is %G_ZLIB_COMPRESSOR_FORMAT_GZIP,
 318  * it will be used to set the file name and modification time in
 319  * the GZIP header of the compressed data.
 320  *
 321  * Note: it is an error to call this function while a compression is in
 322  * progress; it may only be called immediately after creation of @compressor,
 323  * or after resetting it with g_converter_reset().
 324  *
 325  * Since: 2.26
 326  */
 327 void
 328 g_zlib_compressor_set_file_info (GZlibCompressor *compressor,
 329                                  GFileInfo       *file_info)
 330 {
 331   g_return_if_fail (G_IS_ZLIB_COMPRESSOR (compressor));
 332
 333   if (file_info == compressor->file_info)
 334     return;
 335
 336   if (compressor->file_info)
 337     g_object_unref (compressor->file_info);
 338   if (file_info)
 339     g_object_ref (file_info);
 340   compressor->file_info = file_info;
 341   g_object_notify (G_OBJECT (compressor), "file-info");
 342
 343   g_zlib_compressor_set_gzheader (compressor);
 344 }
 345
 346 static void
 347 g_zlib_compressor_reset (GConverter *converter)
 348 {
 349   GZlibCompressor *compressor = G_ZLIB_COMPRESSOR (converter);
 350   int res;
 351
 352   res = deflateReset (&compressor->zstream);
 353   if (res != Z_OK)
 354     g_warning ("unexpected zlib error: %s", compressor->zstream.msg);
 355
 356   /* deflateReset reset the header too, so re-set it */
 357   g_zlib_compressor_set_gzheader (compressor);
 358 }
 359
 360 static GConverterResult
 361 g_zlib_compressor_convert (GConverter *converter,
 362                            const void *inbuf,
 363                            gsize       inbuf_size,
 364                            void       *outbuf,
 365                            gsize       outbuf_size,
 366                            GConverterFlags flags,
 367                            gsize      *bytes_read,
 368                            gsize      *bytes_written,
 369                            GError    **error)
 370 {
 371   GZlibCompressor *compressor;
 372   int res;
 373   int flush;
 374
 375   compressor = G_ZLIB_COMPRESSOR (converter);
 376
 377   compressor->zstream.next_in = (void *)inbuf;
 378   compressor->zstream.avail_in = inbuf_size;
 379
 380   compressor->zstream.next_out = outbuf;
 381   compressor->zstream.avail_out = outbuf_size;
 382
 383   flush = Z_NO_FLUSH;
 384   if (flags & G_CONVERTER_INPUT_AT_END)
 385     flush = Z_FINISH;
 386   else if (flags & G_CONVERTER_FLUSH)
 387     flush = Z_SYNC_FLUSH;
 388
 389   res = deflate (&compressor->zstream, flush);
 390
 391   if (res == Z_MEM_ERROR)
 392     {
 393       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
 394                            _("Not enough memory"));
 395       return G_CONVERTER_ERROR;
 396     }
 397
 398     if (res == Z_STREAM_ERROR)
 399     {
 400       g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
 401                    _("Internal error: %s"), compressor->zstream.msg);
 402       return G_CONVERTER_ERROR;
 403     }
 404
 405     if (res == Z_BUF_ERROR)
 406       {
 407         if (flags & G_CONVERTER_FLUSH)
 408           return G_CONVERTER_FLUSHED;
 409
 410         /* We do have output space, so this should only happen if we
 411            have no input but need some */
 412
 413         g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PARTIAL_INPUT,
 414                              _("Need more input"));
 415         return G_CONVERTER_ERROR;
 416       }
 417
 418   if (res == Z_OK || res == Z_STREAM_END)
 419     {
 420       *bytes_read = inbuf_size - compressor->zstream.avail_in;
 421       *bytes_written = outbuf_size - compressor->zstream.avail_out;
 422
 423       if (res == Z_STREAM_END)
 424         return G_CONVERTER_FINISHED;
 425       return G_CONVERTER_CONVERTED;
 426     }
 427
 428   g_assert_not_reached ();
 429 }
 430
 431 static void
 432 g_zlib_compressor_iface_init (GConverterIface *iface)
 433 {
 434   iface->convert = g_zlib_compressor_convert;
 435   iface->reset = g_zlib_compressor_reset;
 436 }