gio/glocalfileinputstream.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2006-2007 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 <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <fcntl.h>
  28 #ifdef HAVE_UNISTD_H
  29 #include <unistd.h>
  30 #endif
  31 #include <errno.h>
  32
  33 #include <glib.h>
  34 #include <glib/gstdio.h>
  35 #include "gcancellable.h"
  36 #include "gfiledescriptorbased.h"
  37 #include "gioerror.h"
  38 #include "glocalfileinputstream.h"
  39 #include "glocalfileinfo.h"
  40 #include "glibintl.h"
  41
  42 #ifdef G_OS_WIN32
  43 #include <io.h>
  44 #endif
  45
  46 #include "gioalias.h"
  47
  48
  49 static void       g_file_descriptor_based_iface_init   (GFileDescriptorBasedIface *iface);
  50 #define g_local_file_input_stream_get_type _g_local_file_input_stream_get_type
  51 G_DEFINE_TYPE_WITH_CODE (GLocalFileInputStream, g_local_file_input_stream, G_TYPE_FILE_INPUT_STREAM,
  52                          G_IMPLEMENT_INTERFACE (G_TYPE_FILE_DESCRIPTOR_BASED,
  53                                                 g_file_descriptor_based_iface_init));
  54
  55 struct _GLocalFileInputStreamPrivate {
  56   int fd;
  57   guint do_close : 1;
  58 };
  59
  60 static gssize     g_local_file_input_stream_read       (GInputStream      *stream,
  61                                                         void              *buffer,
  62                                                         gsize              count,
  63                                                         GCancellable      *cancellable,
  64                                                         GError           **error);
  65 static gssize     g_local_file_input_stream_skip       (GInputStream      *stream,
  66                                                         gsize              count,
  67                                                         GCancellable      *cancellable,
  68                                                         GError           **error);
  69 static gboolean   g_local_file_input_stream_close      (GInputStream      *stream,
  70                                                         GCancellable      *cancellable,
  71                                                         GError           **error);
  72 static goffset    g_local_file_input_stream_tell       (GFileInputStream  *stream);
  73 static gboolean   g_local_file_input_stream_can_seek   (GFileInputStream  *stream);
  74 static gboolean   g_local_file_input_stream_seek       (GFileInputStream  *stream,
  75                                                         goffset            offset,
  76                                                         GSeekType          type,
  77                                                         GCancellable      *cancellable,
  78                                                         GError           **error);
  79 static GFileInfo *g_local_file_input_stream_query_info (GFileInputStream  *stream,
  80                                                         const char        *attributes,
  81                                                         GCancellable      *cancellable,
  82                                                         GError           **error);
  83 static int        g_local_file_input_stream_get_fd     (GFileDescriptorBased *stream);
  84
  85 static void
  86 g_local_file_input_stream_finalize (GObject *object)
  87 {
  88   G_OBJECT_CLASS (g_local_file_input_stream_parent_class)->finalize (object);
  89 }
  90
  91 void
  92 _g_local_file_input_stream_set_do_close (GLocalFileInputStream *in,
  93                                           gboolean do_close)
  94 {
  95   in->priv->do_close = do_close;
  96 }
  97
  98 static void
  99 g_local_file_input_stream_class_init (GLocalFileInputStreamClass *klass)
 100 {
 101   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 102   GInputStreamClass *stream_class = G_INPUT_STREAM_CLASS (klass);
 103   GFileInputStreamClass *file_stream_class = G_FILE_INPUT_STREAM_CLASS (klass);
 104
 105   g_type_class_add_private (klass, sizeof (GLocalFileInputStreamPrivate));
 106
 107   gobject_class->finalize = g_local_file_input_stream_finalize;
 108
 109   stream_class->read_fn = g_local_file_input_stream_read;
 110   stream_class->skip = g_local_file_input_stream_skip;
 111   stream_class->close_fn = g_local_file_input_stream_close;
 112   file_stream_class->tell = g_local_file_input_stream_tell;
 113   file_stream_class->can_seek = g_local_file_input_stream_can_seek;
 114   file_stream_class->seek = g_local_file_input_stream_seek;
 115   file_stream_class->query_info = g_local_file_input_stream_query_info;
 116 }
 117
 118 static void
 119 g_file_descriptor_based_iface_init (GFileDescriptorBasedIface *iface)
 120 {
 121   iface->get_fd = g_local_file_input_stream_get_fd;
 122 }
 123
 124 static void
 125 g_local_file_input_stream_init (GLocalFileInputStream *info)
 126 {
 127   info->priv = G_TYPE_INSTANCE_GET_PRIVATE (info,
 128                                             G_TYPE_LOCAL_FILE_INPUT_STREAM,
 129                                             GLocalFileInputStreamPrivate);
 130   info->priv->do_close = TRUE;
 131 }
 132
 133 GFileInputStream *
 134 _g_local_file_input_stream_new (int fd)
 135 {
 136   GLocalFileInputStream *stream;
 137
 138   stream = g_object_new (G_TYPE_LOCAL_FILE_INPUT_STREAM, NULL);
 139   stream->priv->fd = fd;
 140
 141   return G_FILE_INPUT_STREAM (stream);
 142 }
 143
 144 static gssize
 145 g_local_file_input_stream_read (GInputStream  *stream,
 146                                 void          *buffer,
 147                                 gsize          count,
 148                                 GCancellable  *cancellable,
 149                                 GError       **error)
 150 {
 151   GLocalFileInputStream *file;
 152   gssize res;
 153
 154   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 155
 156   res = -1;
 157   while (1)
 158     {
 159       if (g_cancellable_set_error_if_cancelled (cancellable, error))
 160         break;
 161       res = read (file->priv->fd, buffer, count);
 162       if (res == -1)
 163         {
 164           int errsv = errno;
 165
 166           if (errsv == EINTR)
 167             continue;
 168
 169           g_set_error (error, G_IO_ERROR,
 170                        g_io_error_from_errno (errsv),
 171                        _("Error reading from file: %s"),
 172                        g_strerror (errsv));
 173         }
 174
 175       break;
 176     }
 177
 178   return res;
 179 }
 180
 181 static gssize
 182 g_local_file_input_stream_skip (GInputStream  *stream,
 183                                 gsize          count,
 184                                 GCancellable  *cancellable,
 185                                 GError       **error)
 186 {
 187   off_t res, start;
 188   GLocalFileInputStream *file;
 189
 190   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 191
 192   if (g_cancellable_set_error_if_cancelled (cancellable, error))
 193     return -1;
 194
 195   start = lseek (file->priv->fd, 0, SEEK_CUR);
 196   if (start == -1)
 197     {
 198       int errsv = errno;
 199
 200       g_set_error (error, G_IO_ERROR,
 201                    g_io_error_from_errno (errsv),
 202                    _("Error seeking in file: %s"),
 203                    g_strerror (errsv));
 204       return -1;
 205     }
 206
 207   res = lseek (file->priv->fd, count, SEEK_CUR);
 208   if (res == -1)
 209     {
 210       int errsv = errno;
 211
 212       g_set_error (error, G_IO_ERROR,
 213                    g_io_error_from_errno (errsv),
 214                    _("Error seeking in file: %s"),
 215                    g_strerror (errsv));
 216       return -1;
 217     }
 218
 219   return res - start;
 220 }
 221
 222 static gboolean
 223 g_local_file_input_stream_close (GInputStream  *stream,
 224                                  GCancellable  *cancellable,
 225                                  GError       **error)
 226 {
 227   GLocalFileInputStream *file;
 228   int res;
 229
 230   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 231
 232   if (!file->priv->do_close)
 233     return TRUE;
 234
 235   if (file->priv->fd == -1)
 236     return TRUE;
 237
 238   while (1)
 239     {
 240       res = close (file->priv->fd);
 241       if (res == -1)
 242         {
 243           int errsv = errno;
 244
 245           g_set_error (error, G_IO_ERROR,
 246                        g_io_error_from_errno (errsv),
 247                        _("Error closing file: %s"),
 248                        g_strerror (errsv));
 249         }
 250       break;
 251     }
 252
 253   return res != -1;
 254 }
 255
 256
 257 static goffset
 258 g_local_file_input_stream_tell (GFileInputStream *stream)
 259 {
 260   GLocalFileInputStream *file;
 261   off_t pos;
 262
 263   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 264
 265   pos = lseek (file->priv->fd, 0, SEEK_CUR);
 266
 267   if (pos == (off_t)-1)
 268     return 0;
 269
 270   return pos;
 271 }
 272
 273 static gboolean
 274 g_local_file_input_stream_can_seek (GFileInputStream *stream)
 275 {
 276   GLocalFileInputStream *file;
 277   off_t pos;
 278
 279   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 280
 281   pos = lseek (file->priv->fd, 0, SEEK_CUR);
 282
 283   if (pos == (off_t)-1 && errno == ESPIPE)
 284     return FALSE;
 285
 286   return TRUE;
 287 }
 288
 289 static int
 290 seek_type_to_lseek (GSeekType type)
 291 {
 292   switch (type)
 293     {
 294     default:
 295     case G_SEEK_CUR:
 296       return SEEK_CUR;
 297
 298     case G_SEEK_SET:
 299       return SEEK_SET;
 300
 301     case G_SEEK_END:
 302       return SEEK_END;
 303     }
 304 }
 305
 306 static gboolean
 307 g_local_file_input_stream_seek (GFileInputStream  *stream,
 308                                 goffset            offset,
 309                                 GSeekType          type,
 310                                 GCancellable      *cancellable,
 311                                 GError           **error)
 312 {
 313   GLocalFileInputStream *file;
 314   off_t pos;
 315
 316   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 317
 318   pos = lseek (file->priv->fd, offset, seek_type_to_lseek (type));
 319
 320   if (pos == (off_t)-1)
 321     {
 322       int errsv = errno;
 323
 324       g_set_error (error, G_IO_ERROR,
 325                    g_io_error_from_errno (errsv),
 326                    _("Error seeking in file: %s"),
 327                    g_strerror (errsv));
 328       return FALSE;
 329     }
 330
 331   return TRUE;
 332 }
 333
 334 static GFileInfo *
 335 g_local_file_input_stream_query_info (GFileInputStream  *stream,
 336                                       const char        *attributes,
 337                                       GCancellable      *cancellable,
 338                                       GError           **error)
 339 {
 340   GLocalFileInputStream *file;
 341
 342   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 343
 344   if (g_cancellable_set_error_if_cancelled (cancellable, error))
 345     return NULL;
 346
 347   return _g_local_file_info_get_from_fd (file->priv->fd,
 348                                          attributes,
 349                                          error);
 350 }
 351
 352 static int
 353 g_local_file_input_stream_get_fd (GFileDescriptorBased *fd_based)
 354 {
 355   GLocalFileInputStream *stream = G_LOCAL_FILE_INPUT_STREAM (fd_based);
 356   return stream->priv->fd;
 357 }
 358