firmware/common/dir_uncached.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id: dir.c 13741 2007-06-30 02:08:27Z jethead71 $
   9  *
  10  * Copyright (C) 2002 by Björn Stenberg
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include <stdio.h>
  22 #include <errno.h>
  23 #include <string.h>
  24 #include <stdbool.h>
  25 #include <stdlib.h>
  26 #include "fat.h"
  27 #include "dir.h"
  28 #include "debug.h"
  29
  30 #if ((defined(MEMORYSIZE) && (MEMORYSIZE > 8)) || MEM > 8)
  31 #define MAX_OPEN_DIRS 12
  32 #else
  33 #define MAX_OPEN_DIRS 8
  34 #endif
  35
  36 static DIR_UNCACHED opendirs[MAX_OPEN_DIRS];
  37
  38 #ifdef HAVE_MULTIVOLUME
  39
  40 /* returns on which volume this is, and copies the reduced name
  41    (sortof a preprocessor for volume-decorated pathnames) */
  42 int strip_volume(const char* name, char* namecopy)
  43 {
  44     int volume = 0;
  45     const char *temp = name;
  46
  47     while (*temp == '/')          /* skip all leading slashes */
  48         ++temp;
  49
  50     if (*temp && !strncmp(temp, VOL_NAMES, VOL_ENUM_POS))
  51     {
  52         temp += VOL_ENUM_POS;     /* behind special name */
  53         volume = atoi(temp);      /* number is following */
  54         temp = strchr(temp, '/'); /* search for slash behind */
  55         if (temp != NULL)
  56             name = temp;          /* use the part behind the volume */
  57         else
  58             name = "/";           /* else this must be the root dir */
  59     }
  60
  61     strlcpy(namecopy, name, MAX_PATH);
  62
  63     return volume;
  64 }
  65 #endif /* #ifdef HAVE_MULTIVOLUME */
  66
  67
  68 #ifdef HAVE_HOTSWAP
  69 // release all dir handles on a given volume "by force", to avoid leaks
  70 int release_dirs(int volume)
  71 {
  72     DIR_UNCACHED* pdir = opendirs;
  73     int dd;
  74     int closed = 0;
  75     for ( dd=0; dd<MAX_OPEN_DIRS; dd++, pdir++)
  76     {
  77         if (pdir->fatdir.file.volume == volume)
  78         {
  79             pdir->busy = false; /* mark as available, no further action */
  80             closed++;
  81         }
  82     }
  83     return closed; /* return how many we did */
  84 }
  85 #endif /* #ifdef HAVE_HOTSWAP */
  86
  87 DIR_UNCACHED* opendir_uncached(const char* name)
  88 {
  89     char namecopy[MAX_PATH];
  90     char* part;
  91     char* end;
  92     struct fat_direntry entry;
  93     int dd;
  94     DIR_UNCACHED* pdir = opendirs;
  95 #ifdef HAVE_MULTIVOLUME
  96     int volume;
  97 #endif
  98
  99     if ( name[0] != '/' ) {
 100         DEBUGF("Only absolute paths supported right now\n");
 101         return NULL;
 102     }
 103
 104     /* find a free dir descriptor */
 105     for ( dd=0; dd<MAX_OPEN_DIRS; dd++, pdir++)
 106         if ( !pdir->busy )
 107             break;
 108
 109     if ( dd == MAX_OPEN_DIRS ) {
 110         DEBUGF("Too many dirs open\n");
 111         errno = EMFILE;
 112         return NULL;
 113     }
 114
 115     pdir->busy = true;
 116
 117 #ifdef HAVE_MULTIVOLUME
 118     /* try to extract a heading volume name, if present */
 119     volume = strip_volume(name, namecopy);
 120     pdir->volumecounter = 0;
 121 #else
 122     strlcpy(namecopy, name, sizeof(namecopy)); /* just copy */
 123 #endif
 124
 125     if ( fat_opendir(IF_MV2(volume,) &pdir->fatdir, 0, NULL) < 0 ) {
 126         DEBUGF("Failed opening root dir\n");
 127         pdir->busy = false;
 128         return NULL;
 129     }
 130
 131     for ( part = strtok_r(namecopy, "/", &end); part;
 132           part = strtok_r(NULL, "/", &end)) {
 133         /* scan dir for name */
 134         while (1) {
 135             if ((fat_getnext(&pdir->fatdir,&entry) < 0) ||
 136                 (!entry.name[0])) {
 137                 pdir->busy = false;
 138                 return NULL;
 139             }
 140             if ( (entry.attr & FAT_ATTR_DIRECTORY) &&
 141                  (!strcasecmp(part, entry.name)) ) {
 142                 pdir->parent_dir = pdir->fatdir;
 143                 if ( fat_opendir(IF_MV2(volume,)
 144                                  &pdir->fatdir,
 145                                  entry.firstcluster,
 146                                  &pdir->parent_dir) < 0 ) {
 147                     DEBUGF("Failed opening dir '%s' (%ld)\n",
 148                            part, entry.firstcluster);
 149                     pdir->busy = false;
 150                     return NULL;
 151                 }
 152 #ifdef HAVE_MULTIVOLUME
 153                 pdir->volumecounter = -1; /* n.a. to subdirs */
 154 #endif
 155                 break;
 156             }
 157         }
 158     }
 159
 160     return pdir;
 161 }
 162
 163 int closedir_uncached(DIR_UNCACHED* dir)
 164 {
 165     dir->busy=false;
 166     return 0;
 167 }
 168
 169 struct dirent_uncached* readdir_uncached(DIR_UNCACHED* dir)
 170 {
 171     struct fat_direntry entry;
 172     struct dirent_uncached* theent = &(dir->theent);
 173
 174     if (!dir->busy)
 175         return NULL;
 176
 177 #ifdef HAVE_MULTIVOLUME
 178     /* Volumes (secondary file systems) get inserted into the root directory
 179         of the first volume, since we have no separate top level. */
 180     if (dir->volumecounter >= 0 /* on a root dir */
 181      && dir->volumecounter < NUM_VOLUMES /* in range */
 182      && dir->fatdir.file.volume == 0) /* at volume 0 */
 183     {   /* fake special directories, which don't really exist, but
 184            will get redirected upon opendir_uncached() */
 185         while (++dir->volumecounter < NUM_VOLUMES)
 186         {
 187             if (fat_ismounted(dir->volumecounter))
 188             {
 189                 memset(theent, 0, sizeof(*theent));
 190                 theent->attribute = FAT_ATTR_DIRECTORY | FAT_ATTR_VOLUME;
 191                 snprintf(theent->d_name, sizeof(theent->d_name),
 192                          VOL_NAMES, dir->volumecounter);
 193                 return theent;
 194             }
 195         }
 196     }
 197 #endif
 198     /* normal directory entry fetching follows here */
 199     if (fat_getnext(&(dir->fatdir),&entry) < 0)
 200         return NULL;
 201
 202     if ( !entry.name[0] )
 203         return NULL;
 204
 205     strlcpy(theent->d_name, entry.name, sizeof(theent->d_name));
 206     theent->attribute = entry.attr;
 207     theent->size = entry.filesize;
 208     theent->startcluster = entry.firstcluster;
 209     theent->wrtdate = entry.wrtdate;
 210     theent->wrttime = entry.wrttime;
 211
 212     return theent;
 213 }
 214
 215 int mkdir_uncached(const char *name)
 216 {
 217     DIR_UNCACHED *dir;
 218     char namecopy[MAX_PATH];
 219     char* end;
 220     char *basename;
 221     char *parent;
 222     struct dirent_uncached *entry;
 223     struct fat_dir newdir;
 224     int rc;
 225
 226     if ( name[0] != '/' ) {
 227         DEBUGF("mkdir: Only absolute paths supported right now\n");
 228         return -1;
 229     }
 230
 231     strlcpy(namecopy, name, sizeof(namecopy));
 232
 233     /* Split the base name and the path */
 234     end = strrchr(namecopy, '/');
 235     *end = 0;
 236     basename = end+1;
 237
 238     if(namecopy == end) /* Root dir? */
 239         parent = "/";
 240     else
 241         parent = namecopy;
 242
 243     DEBUGF("mkdir: parent: %s, name: %s\n", parent, basename);
 244
 245     dir = opendir_uncached(parent);
 246
 247     if(!dir) {
 248         DEBUGF("mkdir: can't open parent dir\n");
 249         return -2;
 250     }
 251
 252     if(basename[0] == 0) {
 253         DEBUGF("mkdir: Empty dir name\n");
 254         errno = EINVAL;
 255         return -3;
 256     }
 257
 258     /* Now check if the name already exists */
 259     while ((entry = readdir_uncached(dir))) {
 260         if ( !strcasecmp(basename, entry->d_name) ) {
 261             DEBUGF("mkdir error: file exists\n");
 262             errno = EEXIST;
 263             closedir_uncached(dir);
 264             return - 4;
 265         }
 266     }
 267
 268     memset(&newdir, 0, sizeof(struct fat_dir));
 269
 270     rc = fat_create_dir(basename, &newdir, &(dir->fatdir));
 271     closedir_uncached(dir);
 272
 273     return rc;
 274 }
 275
 276 int rmdir_uncached(const char* name)
 277 {
 278     int rc;
 279     DIR_UNCACHED* dir;
 280     struct dirent_uncached* entry;
 281
 282     dir = opendir_uncached(name);
 283     if (!dir)
 284     {
 285         errno = ENOENT; /* open error */
 286         return -1;
 287     }
 288
 289     /* check if the directory is empty */
 290     while ((entry = readdir_uncached(dir)))
 291     {
 292         if (strcmp(entry->d_name, ".") &&
 293             strcmp(entry->d_name, ".."))
 294         {
 295             DEBUGF("rmdir error: not empty\n");
 296             errno = ENOTEMPTY;
 297             closedir_uncached(dir);
 298             return -2;
 299         }
 300     }
 301
 302     rc = fat_remove(&(dir->fatdir.file));
 303     if ( rc < 0 ) {
 304         DEBUGF("Failed removing dir: %d\n", rc);
 305         errno = EIO;
 306         rc = rc * 10 - 3;
 307     }
 308
 309     closedir_uncached(dir);
 310     return rc;
 311 }