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