reactos/drivers/filesystems/cdfs/misc.c

   1 /*
   2 *  ReactOS kernel
   3 *  Copyright (C) 2002, 2004 ReactOS Team
   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; either version 2 of the License, or
   8 *  (at your option) any later version.
   9 *
  10 *  This program 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
  13 *  GNU General Public License for more details.
  14 *
  15 *  You should have received a copy of the GNU General Public License along
  16 *  with this program; if not, write to the Free Software Foundation, Inc.,
  17 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19 /* $Id$
  20 *
  21 * COPYRIGHT:        See COPYING in the top level directory
  22 * PROJECT:          ReactOS kernel
  23 * FILE:             services/fs/cdfs/misc.c
  24 * PURPOSE:          CDROM (ISO 9660) filesystem driver
  25 * PROGRAMMER:       Eric Kohl
  26 * UPDATE HISTORY:
  27 */
  28
  29 /* INCLUDES *****************************************************************/
  30
  31 #include "cdfs.h"
  32
  33 #define NDEBUG
  34 #include <debug.h>
  35
  36 /* FUNCTIONS ****************************************************************/
  37
  38 VOID
  39 CdfsSwapString(PWCHAR Out,
  40                PUCHAR In,
  41                ULONG Count)
  42 {
  43     PUCHAR t = (PUCHAR)Out;
  44     ULONG i;
  45
  46     for (i = 0; i < Count; i += 2)
  47     {
  48         t[i] = In[i+1];
  49         t[i+1] = In[i];
  50         if (t[i+1] == 0 && t[i] == ';')
  51             break;
  52     }
  53     if ((i>2)&&(t[i-2] == '.'))
  54     {
  55         t[i-2] = 0;
  56         t[i-1] = 0;
  57     }
  58     t[i] = 0;
  59     t[i+1] = 0;
  60 }
  61
  62
  63 VOID
  64 CdfsDateTimeToSystemTime(PFCB Fcb,
  65                          PLARGE_INTEGER SystemTime)
  66 {
  67     TIME_FIELDS TimeFields;
  68     LARGE_INTEGER LocalTime;
  69
  70     TimeFields.Milliseconds = 0;
  71     TimeFields.Second = Fcb->Entry.Second;
  72     TimeFields.Minute = Fcb->Entry.Minute;
  73     TimeFields.Hour = Fcb->Entry.Hour;
  74
  75     TimeFields.Day = Fcb->Entry.Day;
  76     TimeFields.Month = Fcb->Entry.Month;
  77     TimeFields.Year = Fcb->Entry.Year + 1900;
  78
  79     RtlTimeFieldsToTime(&TimeFields,
  80         &LocalTime);
  81     ExLocalTimeToSystemTime(&LocalTime, SystemTime);
  82 }
  83
  84
  85 VOID
  86 CdfsFileFlagsToAttributes(PFCB Fcb,
  87                           PULONG FileAttributes)
  88 {
  89     /* FIXME: Fix attributes */
  90
  91     *FileAttributes = // FILE_ATTRIBUTE_READONLY |
  92         ((Fcb->Entry.FileFlags & FILE_FLAG_HIDDEN) ? FILE_ATTRIBUTE_HIDDEN : 0) |
  93         ((Fcb->Entry.FileFlags & FILE_FLAG_DIRECTORY) ? FILE_ATTRIBUTE_DIRECTORY : 0) |
  94         ((Fcb->Entry.FileFlags & FILE_FLAG_SYSTEM) ? FILE_ATTRIBUTE_SYSTEM : 0) |
  95         ((Fcb->Entry.FileFlags & FILE_FLAG_READONLY) ? FILE_ATTRIBUTE_READONLY : 0);
  96 }
  97
  98 BOOLEAN
  99 CdfsIsNameLegalDOS8Dot3(IN UNICODE_STRING FileName
 100     )
 101 {
 102     ULONG i;
 103     STRING DbcsName;
 104     CHAR DbcsNameBuffer[12];
 105
 106     /* 8dot3 filename is max 12 length */
 107     if (FileName.Length / sizeof(WCHAR) > 12)
 108     {
 109         return FALSE;
 110     }
 111
 112     for (i = 0; i < FileName.Length / sizeof(WCHAR) ; i++)
 113     {
 114         /* Don't allow spaces in FileName */
 115         if (FileName.Buffer[i] == L' ')
 116             return FALSE;
 117     }
 118
 119     /* If FileName is finishing with a dot, remove it */
 120     if (FileName.Buffer[FileName.Length / sizeof(WCHAR) - 1] == '.')
 121     {
 122         FileName.Length -= sizeof(WCHAR);
 123     }
 124
 125     /* Finally, convert the string to call the FsRtl function */
 126     DbcsName.MaximumLength = 12;
 127     DbcsName.Buffer = DbcsNameBuffer;
 128     if (!NT_SUCCESS(RtlUnicodeStringToCountedOemString(&DbcsName,
 129                                                        &FileName,
 130                                                        FALSE )))
 131     {
 132
 133         return FALSE;
 134     }
 135     return FsRtlIsFatDbcsLegal(DbcsName, FALSE, FALSE, FALSE);
 136 }
 137
 138 VOID
 139 CdfsShortNameCacheGet
 140 (PFCB DirectoryFcb,
 141  PLARGE_INTEGER StreamOffset,
 142  PUNICODE_STRING LongName,
 143  PUNICODE_STRING ShortName)
 144 {
 145     PLIST_ENTRY Entry;
 146     PCDFS_SHORT_NAME ShortNameEntry;
 147     GENERATE_NAME_CONTEXT Context = { 0 };
 148
 149     DPRINT("CdfsShortNameCacheGet(%I64u,%wZ)\n", StreamOffset->QuadPart, LongName);
 150
 151     /* Get the name list resource */
 152     ExAcquireResourceExclusiveLite(&DirectoryFcb->NameListResource, TRUE);
 153
 154     /* Try to find the name in our cache */
 155     for (Entry = DirectoryFcb->ShortNameList.Flink;
 156         Entry != &DirectoryFcb->ShortNameList;
 157         Entry = Entry->Flink)
 158     {
 159         ShortNameEntry = CONTAINING_RECORD(Entry, CDFS_SHORT_NAME, Entry);
 160         if (ShortNameEntry->StreamOffset.QuadPart == StreamOffset->QuadPart)
 161         {
 162             /* Cache hit */
 163             RtlCopyMemory
 164                 (ShortName->Buffer, ShortNameEntry->Name.Buffer,
 165                 ShortNameEntry->Name.Length);
 166             ShortName->Length = ShortNameEntry->Name.Length;
 167             ExReleaseResourceLite(&DirectoryFcb->NameListResource);
 168             DPRINT("Yield short name %wZ from cache\n", ShortName);
 169             return;
 170         }
 171     }
 172
 173     /* Cache miss */
 174     if (!CdfsIsNameLegalDOS8Dot3(*LongName))
 175     {
 176         RtlGenerate8dot3Name(LongName, FALSE, &Context, ShortName);
 177     }
 178     else
 179     {
 180         /* copy short name */
 181         RtlUpcaseUnicodeString
 182             (ShortName,
 183             LongName,
 184             FALSE);
 185     }
 186
 187     DPRINT("Initial Guess %wZ\n", ShortName);
 188
 189     /* Make it unique by scanning the cache and bumping */
 190     /* Note that incrementing the ambiguous name is enough, since we add new
 191     * entries at the tail.  We'll scan over all collisions. */
 192     /* XXX could perform better. */
 193     for (Entry = DirectoryFcb->ShortNameList.Flink;
 194         Entry != &DirectoryFcb->ShortNameList;
 195         Entry = Entry->Flink)
 196     {
 197         ShortNameEntry = CONTAINING_RECORD(Entry, CDFS_SHORT_NAME, Entry);
 198         if (RtlCompareUnicodeString
 199             (ShortName,
 200             &ShortNameEntry->Name,
 201             TRUE) == 0) /* Match */
 202         {
 203             RtlGenerate8dot3Name(LongName, FALSE, &Context, ShortName);
 204             DPRINT("Collide; try %wZ\n", ShortName);
 205         }
 206     }
 207
 208     /* We've scanned over all entries and now have a unique one.  Cache it. */
 209     ShortNameEntry = ExAllocatePoolWithTag(PagedPool, sizeof(CDFS_SHORT_NAME), TAG_FCB);
 210     if (!ShortNameEntry)
 211     {
 212         /* We couldn't cache it, but we can return it.  We run the risk of
 213         * generating a non-unique name later. */
 214         ExReleaseResourceLite(&DirectoryFcb->NameListResource);
 215         DPRINT1("Couldn't cache potentially clashing 8.3 name %wZ\n", ShortName);
 216         return;
 217     }
 218
 219     ShortNameEntry->StreamOffset = *StreamOffset;
 220     ShortNameEntry->Name.Buffer = ShortNameEntry->NameBuffer;
 221     ShortNameEntry->Name.Length = ShortName->Length;
 222     ShortNameEntry->Name.MaximumLength = sizeof(ShortNameEntry->NameBuffer);
 223     RtlCopyMemory
 224         (ShortNameEntry->NameBuffer,
 225         ShortName->Buffer,
 226         ShortName->Length);
 227     InsertTailList(&DirectoryFcb->ShortNameList, &ShortNameEntry->Entry);
 228     ExReleaseResourceLite(&DirectoryFcb->NameListResource);
 229
 230     DPRINT("Returning short name %wZ for long name %wZ\n", ShortName, LongName);
 231 }
 232
 233 /* EOF */