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 "gioerror.h"
  37 #include "glocalfileinputstream.h"
  38 #include "glocalfileinfo.h"
  39 #include "glibintl.h"
  40
  41 #ifdef G_OS_UNIX
  42 #include "glib-unix.h"
  43 #include "gfiledescriptorbased.h"
  44 #endif
  45
  46 #ifdef G_OS_WIN32
  47 #include <io.h>
  48 #endif
  49
  50
  51
  52 #ifdef G_OS_UNIX
  53 static void       g_file_descriptor_based_iface_init   (GFileDescriptorBasedIface *iface);
  54 #endif
  55
  56 #define g_local_file_input_stream_get_type _g_local_file_input_stream_get_type
  57 #ifdef G_OS_UNIX
  58 G_DEFINE_TYPE_WITH_CODE (GLocalFileInputStream, g_local_file_input_stream, G_TYPE_FILE_INPUT_STREAM,
  59                          G_IMPLEMENT_INTERFACE (G_TYPE_FILE_DESCRIPTOR_BASED,
  60                                                 g_file_descriptor_based_iface_init)
  61 );
  62 #else
  63 G_DEFINE_TYPE_WITH_CODE (GLocalFileInputStream, g_local_file_input_stream, G_TYPE_FILE_INPUT_STREAM,);
  64 #endif
  65
  66 struct _GLocalFileInputStreamPrivate {
  67   int fd;
  68   guint do_close : 1;
  69 };
  70
  71 static gssize     g_local_file_input_stream_read       (GInputStream      *stream,
  72                                                         void              *buffer,
  73                                                         gsize              count,
  74                                                         GCancellable      *cancellable,
  75                                                         GError           **error);
  76 static gssize     g_local_file_input_stream_skip       (GInputStream      *stream,
  77                                                         gsize              count,
  78                                                         GCancellable      *cancellable,
  79                                                         GError           **error);
  80 static gboolean   g_local_file_input_stream_close      (GInputStream      *stream,
  81                                                         GCancellable      *cancellable,
  82                                                         GError           **error);
  83 static goffset    g_local_file_input_stream_tell       (GFileInputStream  *stream);
  84 static gboolean   g_local_file_input_stream_can_seek   (GFileInputStream  *stream);
  85 static gboolean   g_local_file_input_stream_seek       (GFileInputStream  *stream,
  86                                                         goffset            offset,
  87                                                         GSeekType          type,
  88                                                         GCancellable      *cancellable,
  89                                                         GError           **error);
  90 static GFileInfo *g_local_file_input_stream_query_info (GFileInputStream  *stream,
  91                                                         const char        *attributes,
  92                                                         GCancellable      *cancellable,
  93                                                         GError           **error);
  94 #ifdef G_OS_UNIX
  95 static int        g_local_file_input_stream_get_fd     (GFileDescriptorBased *stream);
  96 #endif
  97
  98 static void
  99 g_local_file_input_stream_finalize (GObject *object)
 100 {
 101   G_OBJECT_CLASS (g_local_file_input_stream_parent_class)->finalize (object);
 102 }
 103
 104 void
 105 _g_local_file_input_stream_set_do_close (GLocalFileInputStream *in,
 106                                           gboolean do_close)
 107 {
 108   in->priv->do_close = do_close;
 109 }
 110
 111 static void
 112 g_local_file_input_stream_class_init (GLocalFileInputStreamClass *klass)
 113 {
 114   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 115   GInputStreamClass *stream_class = G_INPUT_STREAM_CLASS (klass);
 116   GFileInputStreamClass *file_stream_class = G_FILE_INPUT_STREAM_CLASS (klass);
 117
 118   g_type_class_add_private (klass, sizeof (GLocalFileInputStreamPrivate));
 119
 120   gobject_class->finalize = g_local_file_input_stream_finalize;
 121
 122   stream_class->read_fn = g_local_file_input_stream_read;
 123   stream_class->skip = g_local_file_input_stream_skip;
 124   stream_class->close_fn = g_local_file_input_stream_close;
 125   file_stream_class->tell = g_local_file_input_stream_tell;
 126   file_stream_class->can_seek = g_local_file_input_stream_can_seek;
 127   file_stream_class->seek = g_local_file_input_stream_seek;
 128   file_stream_class->query_info = g_local_file_input_stream_query_info;
 129 }
 130
 131 #ifdef G_OS_UNIX
 132 static void
 133 g_file_descriptor_based_iface_init (GFileDescriptorBasedIface *iface)
 134 {
 135   iface->get_fd = g_local_file_input_stream_get_fd;
 136 }
 137 #endif
 138
 139 static void
 140 g_local_file_input_stream_init (GLocalFileInputStream *info)
 141 {
 142   info->priv = G_TYPE_INSTANCE_GET_PRIVATE (info,
 143                                             G_TYPE_LOCAL_FILE_INPUT_STREAM,
 144                                             GLocalFileInputStreamPrivate);
 145   info->priv->do_close = TRUE;
 146 }
 147
 148 GFileInputStream *
 149 _g_local_file_input_stream_new (int fd)
 150 {
 151   GLocalFileInputStream *stream;
 152
 153   stream = g_object_new (G_TYPE_LOCAL_FILE_INPUT_STREAM, NULL);
 154   stream->priv->fd = fd;
 155
 156   return G_FILE_INPUT_STREAM (stream);
 157 }
 158
 159 static gssize
 160 g_local_file_input_stream_read (GInputStream  *stream,
 161                                 void          *buffer,
 162                                 gsize          count,
 163                                 GCancellable  *cancellable,
 164                                 GError       **error)
 165 {
 166   GLocalFileInputStream *file;
 167   gssize res;
 168
 169   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 170
 171   res = -1;
 172   while (1)
 173     {
 174       if (g_cancellable_set_error_if_cancelled (cancellable, error))
 175         break;
 176       res = read (file->priv->fd, buffer, count);
 177       if (res == -1)
 178         {
 179           int errsv = errno;
 180
 181           if (errsv == EINTR)
 182             continue;
 183
 184           g_set_error (error, G_IO_ERROR,
 185                        g_io_error_from_errno (errsv),
 186                        _("Error reading from file: %s"),
 187                        g_strerror (errsv));
 188         }
 189
 190       break;
 191     }
 192
 193   return res;
 194 }
 195
 196 static gssize
 197 g_local_file_input_stream_skip (GInputStream  *stream,
 198                                 gsize          count,
 199                                 GCancellable  *cancellable,
 200                                 GError       **error)
 201 {
 202   off_t res, start;
 203   GLocalFileInputStream *file;
 204
 205   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 206
 207   if (g_cancellable_set_error_if_cancelled (cancellable, error))
 208     return -1;
 209
 210   start = lseek (file->priv->fd, 0, SEEK_CUR);
 211   if (start == -1)
 212     {
 213       int errsv = errno;
 214
 215       g_set_error (error, G_IO_ERROR,
 216                    g_io_error_from_errno (errsv),
 217                    _("Error seeking in file: %s"),
 218                    g_strerror (errsv));
 219       return -1;
 220     }
 221
 222   res = lseek (file->priv->fd, count, SEEK_CUR);
 223   if (res == -1)
 224     {
 225       int errsv = errno;
 226
 227       g_set_error (error, G_IO_ERROR,
 228                    g_io_error_from_errno (errsv),
 229                    _("Error seeking in file: %s"),
 230                    g_strerror (errsv));
 231       return -1;
 232     }
 233
 234   return res - start;
 235 }
 236
 237 static gboolean
 238 g_local_file_input_stream_close (GInputStream  *stream,
 239                                  GCancellable  *cancellable,
 240                                  GError       **error)
 241 {
 242   GLocalFileInputStream *file;
 243
 244   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 245
 246   if (!file->priv->do_close)
 247     return TRUE;
 248
 249   if (file->priv->fd == -1)
 250     return TRUE;
 251
 252   if (!g_close (file->priv->fd, NULL))
 253     {
 254       int errsv = errno;
 255
 256       g_set_error (error, G_IO_ERROR,
 257                    g_io_error_from_errno (errsv),
 258                    _("Error closing file: %s"),
 259                    g_strerror (errsv));
 260       return FALSE;
 261     }
 262
 263   return TRUE;
 264 }
 265
 266
 267 static goffset
 268 g_local_file_input_stream_tell (GFileInputStream *stream)
 269 {
 270   GLocalFileInputStream *file;
 271   off_t pos;
 272
 273   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 274
 275   pos = lseek (file->priv->fd, 0, SEEK_CUR);
 276
 277   if (pos == (off_t)-1)
 278     return 0;
 279
 280   return pos;
 281 }
 282
 283 static gboolean
 284 g_local_file_input_stream_can_seek (GFileInputStream *stream)
 285 {
 286   GLocalFileInputStream *file;
 287   off_t pos;
 288
 289   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 290
 291   pos = lseek (file->priv->fd, 0, SEEK_CUR);
 292
 293   if (pos == (off_t)-1 && errno == ESPIPE)
 294     return FALSE;
 295
 296   return TRUE;
 297 }
 298
 299 static int
 300 seek_type_to_lseek (GSeekType type)
 301 {
 302   switch (type)
 303     {
 304     default:
 305     case G_SEEK_CUR:
 306       return SEEK_CUR;
 307
 308     case G_SEEK_SET:
 309       return SEEK_SET;
 310
 311     case G_SEEK_END:
 312       return SEEK_END;
 313     }
 314 }
 315
 316 static gboolean
 317 g_local_file_input_stream_seek (GFileInputStream  *stream,
 318                                 goffset            offset,
 319                                 GSeekType          type,
 320                                 GCancellable      *cancellable,
 321                                 GError           **error)
 322 {
 323   GLocalFileInputStream *file;
 324   off_t pos;
 325
 326   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 327
 328   pos = lseek (file->priv->fd, offset, seek_type_to_lseek (type));
 329
 330   if (pos == (off_t)-1)
 331     {
 332       int errsv = errno;
 333
 334       g_set_error (error, G_IO_ERROR,
 335                    g_io_error_from_errno (errsv),
 336                    _("Error seeking in file: %s"),
 337                    g_strerror (errsv));
 338       return FALSE;
 339     }
 340
 341   return TRUE;
 342 }
 343
 344 static GFileInfo *
 345 g_local_file_input_stream_query_info (GFileInputStream  *stream,
 346                                       const char        *attributes,
 347                                       GCancellable      *cancellable,
 348                                       GError           **error)
 349 {
 350   GLocalFileInputStream *file;
 351
 352   file = G_LOCAL_FILE_INPUT_STREAM (stream);
 353
 354   if (g_cancellable_set_error_if_cancelled (cancellable, error))
 355     return NULL;
 356
 357   return _g_local_file_info_get_from_fd (file->priv->fd,
 358                                          attributes,
 359                                          error);
 360 }
 361
 362 #ifdef G_OS_UNIX
 363 static int
 364 g_local_file_input_stream_get_fd (GFileDescriptorBased *fd_based)
 365 {
 366   GLocalFileInputStream *stream = G_LOCAL_FILE_INPUT_STREAM (fd_based);
 367   return stream->priv->fd;
 368 }
 369 #endif