rom/dos/exall.c

   1 /*
   2     Copyright © 1995-2012, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Examine a directory.
   6     Lang: English
   7 */
   8 #include <exec/memory.h>
   9 #include <proto/exec.h>
  10 #include <dos/exall.h>
  11 #include <stddef.h>
  12 #include "dos_intern.h"
  13 #include <aros/asmcall.h>
  14 #include <aros/debug.h>
  15
  16 /*****************************************************************************
  17
  18     NAME */
  19 #include <proto/dos.h>
  20
  21         AROS_LH5(BOOL, ExAll,
  22
  23 /*  SYNOPSIS */
  24         AROS_LHA(BPTR,                  lock,    D1),
  25         AROS_LHA(struct ExAllData *,    buffer,  D2),
  26         AROS_LHA(LONG,                  size,    D3),
  27         AROS_LHA(LONG,                  data,    D4),
  28         AROS_LHA(struct ExAllControl *, control, D5),
  29
  30 /*  LOCATION */
  31         struct DosLibrary *, DOSBase, 72, Dos)
  32
  33 /*  FUNCTION
  34
  35     Examine an entire directory.
  36
  37     INPUTS
  38
  39     lock     --  lock on the directory to be examined
  40     buffer   --  buffer for the data that is returned (must be aligned)
  41                  which is filled with (partial) ExAllData structures
  42                  (see NOTES)
  43     size     --  size of 'buffer' in bytes
  44     data     --  type of the data to be returned
  45     control  --  a control structure allocated by AllocDosObject()
  46
  47     RESULT
  48
  49     An indicator of if ExAll() is done. If FALSE is returned, either ExAll()
  50     has completed in which case IoErr() is ERROR_NO_MORE_ENTRIES or an
  51     error occurred. If a non-zero value is returned ExAll() must be called
  52     again until it returns FALSE.
  53
  54     NOTES
  55
  56     The following information is essential information on the ExAllData
  57     structure:
  58
  59     ed_Type:
  60
  61     ED_NAME        --  filename
  62     ED_TYPE        --  type
  63     ED_SIZE        --  size in bytes
  64     ED_PROTECTION  --  protection bits
  65     ED_DATE        --  date information (3 longwords)
  66     ED_COMMENT     --  file comment (NULL if no comment exists)
  67     ED_OWNER       --  owner user and group id
  68
  69     This is an incremental list meaning that if you specify ED_OWNER you
  70     will get ALL attributes!
  71
  72
  73     Filesystems that support ExAll() must support at least up to ED_COMMENT.
  74     If a filesystem doesn't support a particular type, ERROR_BAD_NUMBER must
  75     be returned.
  76
  77     ed_Next : pointer to the next entry in the buffer. The last entry
  78                has a NULL value for ed_Next.
  79
  80
  81     The control structure have the following fields.
  82
  83     eac_Entries : the number of entries in the buffer after a call to ExAll().
  84                   Make sure that your code handles the case when eac_Entries
  85                   is 0 and ExAll() returns TRUE.
  86
  87     eac_LastKey : must be initialized to 0 before calling ExAll() for the
  88                   first time.
  89
  90     eac_MatchString : if NULL then information on all files will be returned.
  91                       If non-NULL it's interpreted as a pointer to a string
  92                       used for pattern matching which files to return
  93                       information on. This string must have been parsed by
  94                       ParsePatternNoCase()!
  95
  96     eac_MatchFunc : pointer to a hook that will be called to decide if an
  97                     entry should be included in the buffer. If NULL, no
  98                     matching function will be called. The hook is called as
  99                     follows
 100
 101                         BOOL = MatchFunc(hook, data, typeptr)
 102
 103     EXAMPLE
 104
 105     BUGS
 106
 107     SEE ALSO
 108
 109     Examine(), ExNext(), MatchPatternNoCase(), ParsePatternNoCase(),
 110     AllocDosObject(), ExAllEnd()
 111
 112     INTERNALS
 113
 114 *****************************************************************************/
 115 {
 116     AROS_LIBFUNC_INIT
 117
 118     /* Get pointer to filehandle */
 119     struct FileLock *fl = BADDR(lock);
 120     LONG status = 0;
 121     SIPTR err = 0;
 122
 123     /* If fib != NULL it means we've already been called and found out that
 124        we needed to emulate ExAll, thus don't waste time sending messages to the
 125        handler.  */
 126     if (((struct InternalExAllControl *)control)->fib != NULL)
 127     {
 128         err = ERROR_ACTION_NOT_KNOWN;
 129     }
 130     else
 131     {
 132         status = dopacket5(DOSBase, &err, fl->fl_Task, ACTION_EXAMINE_ALL, (SIPTR)lock, (IPTR)buffer, (IPTR)size, (IPTR)data, (IPTR)control);
 133         if (status != DOSFALSE)
 134             err = RETURN_OK;
 135     }
 136
 137     if
 138     (
 139         err == ERROR_NOT_IMPLEMENTED ||
 140         err == ERROR_ACTION_NOT_KNOWN
 141     )
 142     {
 143         /* Try to emulate it */
 144         STRPTR end  = (STRPTR)buffer + size;
 145         STRPTR next;
 146
 147         struct ExAllData *last = buffer, *curr = buffer;
 148
 149         struct InternalExAllControl *icontrol = (struct InternalExAllControl *)control;
 150
 151         static const ULONG sizes[]=
 152         {
 153             0,
 154             offsetof(struct ExAllData,ed_Type),
 155             offsetof(struct ExAllData,ed_Size),
 156             offsetof(struct ExAllData,ed_Prot),
 157             offsetof(struct ExAllData,ed_Days),
 158             offsetof(struct ExAllData,ed_Comment),
 159             offsetof(struct ExAllData,ed_OwnerUID),
 160             sizeof(struct ExAllData)
 161         };
 162
 163         /* Reset the 'fake' error */
 164         err = 0;
 165
 166         /* Allocate the FIB structure, if not allocated yet. It will be deallocated
 167            by DeleteDosObject().  */
 168         if (!icontrol->fib)
 169         {
 170             icontrol->fib = AllocDosObject(DOS_FIB, NULL);
 171             if (!icontrol->fib)
 172             {
 173                 err = IoErr();
 174                 goto end;
 175             }
 176         }
 177
 178         /* No entries found as of now yet.  */
 179         control->eac_Entries = 0;
 180
 181         /* If LastKey == 0 it means this is the first time we're getting called,
 182            in which case we need to initialize the FIB structure and a few other things.
 183            A "nice" side effect of this, is that if one wants to restart the scanning,
 184            he/she just has to set LastKey to 0.  */
 185         if (control->eac_LastKey == 0)
 186         {
 187             if (!Examine(lock, icontrol->fib))
 188             {
 189                 err = IoErr();
 190                 goto end;
 191             }
 192             if (icontrol->fib->fib_DirEntryType <= 0)
 193             {
 194                 err = ERROR_OBJECT_WRONG_TYPE;
 195                 goto end;
 196             }
 197         }
 198
 199         /* Macro used when the data doesn't fit in the provided buffer.
 200            In case not even one element fit in the buffer, return a buffer
 201            overflow error, so that the user knows he/she has to increase the
 202            buffer.  */
 203         #define ReturnOverflow()                               \
 204         do {                                                   \
 205             if (last == curr)                                  \
 206                 err = ERROR_BUFFER_OVERFLOW;                   \
 207                                                                \
 208             icontrol->fib->fib_DiskKey = control->eac_LastKey; \
 209             goto end;                                          \
 210         } while (0)
 211
 212         /* Copy a string pointer by _source into the buffer provided
 213            to the ExAll function. This macro gracefully handles buffer
 214            overflows.  */
 215         #define CopyStringSafe(_source)     \
 216         do {                                \
 217             STRPTR source = _source;        \
 218                                             \
 219             for (;;)                        \
 220             {                               \
 221                 if (next >= end)            \
 222                     ReturnOverflow();       \
 223                 if (!(*next++ = *source++)) \
 224                    break;                   \
 225                 }                           \
 226             } while (0)
 227
 228
 229         if (data > ED_OWNER)
 230             /* We don't have that many fields to fill in... */
 231             err = ERROR_BAD_NUMBER;
 232         else
 233         {
 234             for
 235             (   ;
 236                 ExNext(lock, icontrol->fib);
 237                 /* Record the latest DiskKey into LastKey so that we can roll back to it
 238                    in case of a buffer overflow and when getting called again.  */
 239                 control->eac_LastKey = icontrol->fib->fib_DiskKey
 240             )
 241             {
 242                 /* Try to match the filename, if required.  */
 243                 if (control->eac_MatchString &&
 244                     !MatchPatternNoCase(control->eac_MatchString,
 245                                         icontrol->fib->fib_FileName))
 246                     continue;
 247
 248                 next = (STRPTR)curr + sizes[data];
 249
 250                 /* Oops, the buffer is full.  */
 251                 if (next > end)
 252                     ReturnOverflow();
 253
 254                 /* Switch over the requested fields and fill them as appropriate.  */
 255                 switch(data)
 256                 {
 257                     case ED_OWNER:
 258                         curr->ed_OwnerUID = icontrol->fib->fib_OwnerUID;
 259                         curr->ed_OwnerGID = icontrol->fib->fib_OwnerGID;
 260
 261                         /* Fall through */
 262                     case ED_COMMENT:
 263                         curr->ed_Comment = next;
 264                         CopyStringSafe(icontrol->fib->fib_Comment);
 265
 266                         /* Fall through */
 267                     case ED_DATE:
 268                         curr->ed_Days  = icontrol->fib->fib_Date.ds_Days;
 269                         curr->ed_Mins  = icontrol->fib->fib_Date.ds_Minute;
 270                         curr->ed_Ticks = icontrol->fib->fib_Date.ds_Tick;
 271
 272                         /* Fall through */
 273                     case ED_PROTECTION:
 274                         curr->ed_Prot = icontrol->fib->fib_Protection;
 275
 276                         /* Fall through */
 277                     case ED_SIZE:
 278                         curr->ed_Size = icontrol->fib->fib_Size;
 279
 280                         /* Fall through */
 281                     case ED_TYPE:
 282                         curr->ed_Type = icontrol->fib->fib_DirEntryType;
 283
 284                         /* Fall through */
 285                     case ED_NAME:
 286                         curr->ed_Name = next;
 287                         CopyStringSafe(icontrol->fib->fib_FileName);
 288
 289                         /* Fall through */
 290                     case 0:
 291                         curr->ed_Next = (struct ExAllData *)(((IPTR)next + AROS_PTRALIGN - 1) & ~(AROS_PTRALIGN - 1));
 292                 }
 293
 294                 /* Do some more matching... */
 295                 if (control->eac_MatchFunc && !CALLHOOKPKT(control->eac_MatchFunc, curr, &data))
 296                     continue;
 297
 298                 /* Finally go to the next entry in the buffer.  */
 299                 last = curr;
 300                 curr = curr->ed_Next;
 301                 control->eac_Entries++;
 302             }
 303             err = IoErr();
 304         }
 305 end:
 306         /* This is the last one, after it there's nothing.  */
 307         last->ed_Next = NULL;
 308     }
 309
 310     /* Set error code and return */
 311     SetIoErr(err);
 312     return (err == 0) ? DOSTRUE : DOSFALSE;
 313
 314     AROS_LIBFUNC_EXIT
 315 } /* ExAll */