src/client/lufs/captivefs-vfs.c

   1 /* $Id$
   2  * lufs interface module vfs objects implementation for libcaptive
   3  * Copyright (C) 2003 Jan Kratochvil <project-captive@jankratochvil.net>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; exactly version 2 of June 1991 is required
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18
  19
  20 #include "config.h"
  21
  22 #include "captivefs-vfs.h"      /* self */
  23 #include <glib/gmessages.h>
  24 #include "captivefs-misc.h"
  25 #include <unistd.h>
  26
  27 #include <captive/client-vfs.h>
  28 #include <captive/options.h>
  29 #include <captive/macros.h>
  30
  31 #include <lufs/fs.h>
  32 #include <lufs/proto.h>
  33
  34
  35 gboolean captivefs_vfs_validate(struct captivefs_vfs *captivefs_vfs)
  36 {
  37         g_return_val_if_fail(captivefs_vfs!=NULL,FALSE);
  38
  39         G_LOCK(libcaptive);
  40         g_assert(captivefs_vfs->inits>0);
  41         g_assert(captivefs_vfs->mounts>=0);
  42         g_assert(captivefs_vfs->mounts<=captivefs_vfs->inits);
  43         if (!captivefs_vfs->captive_vfs_object) {
  44 GnomeVFSResult errvfsresult;
  45
  46                 if (captivefs_vfs->parent_pid==getpid()) {
  47                         G_UNLOCK(libcaptive);
  48                         return FALSE;
  49                         }
  50
  51                 errvfsresult=captive_vfs_new(&captivefs_vfs->captive_vfs_object,&captivefs_vfs->options);
  52
  53                 if (errvfsresult!=GNOME_VFS_OK) {
  54                         G_UNLOCK(libcaptive);
  55                         g_return_val_if_reached(FALSE);
  56                         }
  57                 }
  58         if (!CAPTIVE_VFS_IS_OBJECT(captivefs_vfs->captive_vfs_object)) {
  59                 G_UNLOCK(libcaptive);
  60                 g_return_val_if_reached(FALSE);
  61                 }
  62         G_UNLOCK(libcaptive);
  63
  64         return TRUE;
  65 }
  66
  67
  68 /* Initialization
  69  * Here we allocate a structure to hold all the file system local info
  70  * (localfs_local). This structure will then be passed as a parameter to
  71  * the other functions.
  72  * global_ctx holds info about another structure that can be shared between all
  73  * instances of the filesystem. If the pointer is NULL, then this is the
  74  * first instance and the structure should be allocated.
  75  * ! You must implement  locking/usage-count/deallocation logic when using
  76  *   a global context. (locking is omited here)
  77  * ! Most filesystems don't need a global context so you can safely ignore the
  78  *   global_ctx parameter.
  79  */
  80 struct captivefs_vfs *captivefs_init
  81                 (struct list_head *cfg,struct dir_cache *cache,const struct credentials *cred,struct captivefs_vfs **global_ctx)
  82 {
  83 struct captivefs_vfs *captivefs_vfs;
  84 const gchar *cgs;
  85 gchar *gs,*captive_options_string;
  86
  87         g_return_val_if_fail(global_ctx!=NULL,NULL);
  88
  89         /* Do not: g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"captivefs_init");
  90          * as we do not yet have 'VFS_DEBUG_MESSAGES(captive_vfs_object)' set.
  91          * Generally we make all g_log() conditional here as we do not want to mess
  92          * with overriden GLog handlers of libcaptive itself.
  93          */
  94
  95         G_LOCK(libcaptive);
  96         if ((captivefs_vfs=*global_ctx)) {
  97                 g_assert(captivefs_vfs->inits>0);
  98                 /* We do not support multiple LUFS threads if they could not be cross-locked. */
  99                 g_return_val_if_fail(g_thread_supported(),NULL);
 100                 captivefs_vfs->inits++;
 101                 G_UNLOCK(libcaptive);
 102                 return captivefs_vfs;
 103                 }
 104         G_UNLOCK(libcaptive);
 105
 106         if (!g_thread_supported())
 107                 g_thread_init(NULL);    /* g_thread_init() fails on second initialization */
 108
 109         /* Initialize GObject subsystem of GLib. */
 110         g_type_init();
 111
 112         captive_new(captivefs_vfs);
 113         captivefs_vfs->captive_vfs_object=NULL;
 114         captivefs_vfs->parent_pid=getpid();
 115         captivefs_vfs->global_ctx=global_ctx;
 116         *global_ctx=captivefs_vfs;
 117         captivefs_vfs->inits=1;
 118         captivefs_vfs->mounts=0;
 119
 120         captive_options_init(&captivefs_vfs->options);
 121
 122         if ((cgs=lu_opt_getchar(cfg,"MOUNT","captive_options"))) {
 123                 captive_options_string=(/* de-const */gchar *)captive_strdup_alloca(cgs);
 124                 /* Convert ';' to ' ' to prevent its parsing by LUFS to keep its ordering
 125                  * to let the options be overridable by user (such as 'ro').
 126                  */
 127                 for (gs=captive_options_string;(gs=strchr(gs,';'));gs++)
 128                         *gs=' ';
 129                 if (!captive_options_parse(
 130                                 &captivefs_vfs->options,        /* options */
 131                                 captive_options_string))        /* captive_args */
 132                         goto fail_free_options;
 133                 }
 134
 135         if (captivefs_vfs->options.debug_messages)
 136                 g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"captivefs_init");
 137
 138         /* image_iochannel */
 139         if ((cgs=lu_opt_getchar(cfg,"MOUNT","image"))) {
 140                 g_assert(captivefs_vfs->options.image_iochannel==NULL);
 141                 if (!(captivefs_vfs->options.image_iochannel=g_io_channel_new_file(
 142                                 cgs,    /* filename */
 143                                 (captivefs_vfs->options.rwmode==CAPTIVE_OPTION_RWMODE_RW ? "r+" : "r"), /* mode */
 144                                 NULL))) {       /* error */
 145                         g_warning(_("%s: image_iochannel open failed"),"captivefs_init");
 146                         goto fail_free_options;
 147                         }
 148                 }
 149
 150         return captivefs_vfs;
 151
 152 fail_free_options:
 153         captive_options_free(&captivefs_vfs->options);
 154 /* fail: */
 155         return NULL;
 156 }
 157
 158
 159 /* Cleanup
 160  * Check the global context count and free it if necessary.
 161  * Deallocate memory and free all resources.
 162  */
 163 void captivefs_free(struct captivefs_vfs *captivefs_vfs)
 164 {
 165         g_return_if_fail(captivefs_vfs_validate(captivefs_vfs));
 166         g_return_if_fail(captivefs_vfs->inits>0);
 167
 168         if (captivefs_vfs->options.debug_messages)
 169                 g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"captivefs_free");
 170
 171         if (--captivefs_vfs->inits>0) {
 172                 g_assert(captivefs_vfs_validate(captivefs_vfs));
 173                 return;
 174                 }
 175         g_assert(captivefs_vfs->mounts==0);
 176         G_LOCK(libcaptive);
 177         *captivefs_vfs->global_ctx=NULL;
 178         G_UNLOCK(libcaptive);
 179
 180         g_assert(G_OBJECT(captivefs_vfs->captive_vfs_object)->ref_count==1);
 181
 182         G_LOCK(libcaptive);
 183         g_object_unref(captivefs_vfs->captive_vfs_object);
 184         G_UNLOCK(libcaptive);
 185
 186         g_io_channel_unref(captivefs_vfs->options.image_iochannel);
 187         captive_options_free(&captivefs_vfs->options);
 188         g_free(captivefs_vfs);
 189 }
 190
 191
 192 /* Mount the file system.
 193  * Called when a mount operation is performed.
 194  * Initialize specific connections, login, etc.
 195  *
 196  * Notes:
 197  *     By default, LUFS may attempt multiple connections at once.  If your
 198  * filesystem doesn't support this, you need to specificy -c 1 on the
 199  * lufsmount command line or connections=1 in the mount options.
 200  *     See ftpfs for an example of how to read configuration options
 201  * from a configuration file if you want to, for example, be able to set
 202  * default values.
 203  */
 204 int captivefs_mount(struct captivefs_vfs *captivefs_vfs)
 205 {
 206         /* We may be called from the parent. */
 207         g_return_val_if_fail(captivefs_vfs!=NULL,FALSE);
 208         captivefs_vfs_validate(captivefs_vfs);  /* It may return FALSE. */
 209
 210         if (captivefs_vfs->options.debug_messages)
 211                 g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"captivefs_mount");
 212
 213         captivefs_vfs->mounts++;
 214
 215         captivefs_vfs_validate(captivefs_vfs);  /* It may return FALSE. */
 216
 217         return 1;       /* NEVER return 0 */
 218 }
 219
 220
 221 /* Unmount the  file system
 222  * Called when the file system is unmounted.
 223  */
 224 void captivefs_umount(struct captivefs_vfs *captivefs_vfs)
 225 {
 226         g_return_if_fail(captivefs_vfs_validate(captivefs_vfs));
 227         g_return_if_fail(captivefs_vfs->mounts>0);
 228
 229         if (captivefs_vfs->options.debug_messages)
 230                 g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"captivefs_umount");
 231
 232         captivefs_vfs->mounts--;
 233
 234         g_assert(captivefs_vfs_validate(captivefs_vfs));
 235 }
 236
 237
 238 #ifdef HAVE_STRUCT_LUFS_SBATTR
 239 int captivefs_statfs(struct captivefs_vfs *captivefs_vfs,struct lufs_sbattr *sbattr)
 240 {
 241 CaptiveVfsVolumeInfo captive_volume_info;
 242 GnomeVFSResult errvfsresult;
 243
 244         g_return_val_if_fail(captivefs_vfs_validate(captivefs_vfs),-1);
 245         g_return_val_if_fail(sbattr!=NULL,-1);
 246
 247         if (captivefs_vfs->options.debug_messages)
 248                 g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"captivefs_statfs");
 249
 250         G_LOCK(libcaptive);
 251         errvfsresult=captive_vfs_volume_info_get(captivefs_vfs->captive_vfs_object,&captive_volume_info);
 252         G_UNLOCK(libcaptive);
 253         if (errvfsresult!=GNOME_VFS_OK)
 254                 return -1;
 255
 256         sbattr->sb_bytes=captive_volume_info.bytes;
 257         sbattr->sb_bytes_free=captive_volume_info.bytes_free;
 258         sbattr->sb_bytes_available=captive_volume_info.bytes_available;
 259         /* 'sbattr->sb_files' not known - left unchanged. */
 260         /* 'sbattr->sb_ffree' not known - left unchanged. */
 261
 262         return 0;
 263 }
 264 #endif /* HAVE_STRUCT_LUFS_SBATTR */