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