rom/dos/open.c

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Open a file with the specified mode.
   6     Lang: english
   7 */
   8 #include <exec/memory.h>
   9 #include <exec/lists.h>
  10 #include <proto/exec.h>
  11 #include <utility/tagitem.h>
  12 #include <dos/dosextens.h>
  13 #include <dos/filesystem.h>
  14 #include <dos/stdio.h>
  15 #include <proto/dos.h>
  16 #include <proto/utility.h>
  17 #include "dos_intern.h"
  18
  19 /*****************************************************************************
  20
  21     NAME */
  22 #include <proto/dos.h>
  23
  24         AROS_LH2(BPTR, Open,
  25
  26 /*  SYNOPSIS */
  27         AROS_LHA(CONST_STRPTR, name,       D1),
  28         AROS_LHA(LONG,         accessMode, D2),
  29
  30 /*  LOCATION */
  31         struct DosLibrary *, DOSBase, 5, Dos)
  32
  33 /*  FUNCTION
  34         Opens a file for read and/or write depending on the accessmode given.
  35
  36     INPUTS
  37         name       - NUL terminated name of the file.
  38         accessMode - One of MODE_OLDFILE   - open existing file
  39                             MODE_NEWFILE   - delete old, create new file
  40                                              exclusive lock
  41                             MODE_READWRITE - open new one if it doesn't exist
  42
  43     RESULT
  44         Handle to the file or 0 if the file couldn't be opened.
  45         IoErr() gives additional information in that case.
  46
  47     NOTES
  48
  49     EXAMPLE
  50
  51     BUGS
  52
  53     SEE ALSO
  54
  55     INTERNALS
  56
  57 *****************************************************************************/
  58 {
  59     AROS_LIBFUNC_INIT
  60
  61     struct FileHandle *ret;
  62     BPTR con, ast;
  63     LONG error;
  64     struct Process *me;
  65
  66     /* Sanity check */
  67     if (name == NULL) return NULL;
  68
  69     /* Get pointer to process structure */
  70     me = (struct Process *)FindTask(NULL);
  71
  72     /* check for an empty filename. this supports this form that was required
  73      * pre-2.0, which didn't have OpenFromLock():
  74      *
  75      *     old = CurrentDir(lock);
  76      *     fh = Open("", MODE_OLDFILE);
  77      *     CurrentDir(old);
  78      */
  79     if (*name == '\0')
  80         return OpenFromLock(DupLock(me->pr_CurrentDir));
  81
  82     /* Create filehandle */
  83     ret = (struct FileHandle *)AllocDosObject(DOS_FILEHANDLE,NULL);
  84
  85     if(ret != NULL)
  86     {
  87         LONG doappend = 0;
  88
  89         /* Get pointer to I/O request. Use stackspace for now. */
  90         struct IOFileSys iofs;
  91
  92         /* Prepare I/O request. */
  93         InitIOFS(&iofs, FSA_OPEN_FILE, DOSBase);
  94
  95         switch(accessMode)
  96         {
  97         case MODE_OLDFILE:
  98             iofs.io_Union.io_OPEN_FILE.io_FileMode = FMF_MODE_OLDFILE;
  99             ast = con = me->pr_CIS;
 100             break;
 101
 102         case MODE_NEWFILE:
 103             iofs.io_Union.io_OPEN_FILE.io_FileMode = FMF_MODE_NEWFILE;
 104             con = me->pr_COS;
 105             ast = me->pr_CES ? me->pr_CES : me->pr_COS;
 106             break;
 107
 108         case MODE_READWRITE:
 109             iofs.io_Union.io_OPEN_FILE.io_FileMode = FMF_MODE_READWRITE;
 110             con = me->pr_COS;
 111             ast = me->pr_CES ? me->pr_CES : me->pr_COS;
 112             break;
 113
 114         default:
 115             /* See if the user requested append mode */
 116             doappend   = accessMode & FMF_APPEND;
 117
 118             /* The append mode is all taken care by dos.library */
 119             accessMode &= ~FMF_APPEND;
 120
 121             iofs.io_Union.io_OPEN_FILE.io_FileMode = accessMode;
 122             ast = con = me->pr_CIS;
 123             break;
 124         }
 125
 126         iofs.io_Union.io_OPEN_FILE.io_Protection = 0;
 127
 128         if(!Stricmp(name, "CONSOLE:"))
 129         {
 130             iofs.IOFS.io_Device = ((struct FileHandle *)BADDR(con))->fh_Device;
 131             iofs.IOFS.io_Unit   = ((struct FileHandle *)BADDR(con))->fh_Unit;
 132             iofs.io_Union.io_OPEN_FILE.io_Filename = "";
 133             DosDoIO(&iofs.IOFS);
 134             error = me->pr_Result2 = iofs.io_DosError;
 135         }
 136         else
 137         if(!Stricmp(name, "*"))
 138         {
 139             iofs.IOFS.io_Device = ((struct FileHandle *)BADDR(ast))->fh_Device;
 140             iofs.IOFS.io_Unit   = ((struct FileHandle *)BADDR(ast))->fh_Unit;
 141             iofs.io_Union.io_OPEN_FILE.io_Filename = "";
 142             DosDoIO(&iofs.IOFS);
 143             error = me->pr_Result2 = iofs.io_DosError;
 144         }
 145         else {
 146             struct DevProc *dvp = NULL;
 147
 148             iofs.io_Union.io_OPEN_FILE.io_Filename = StripVolume(name);
 149
 150             do {
 151                 if ((dvp = GetDeviceProc(name, dvp)) == NULL) {
 152                     error = IoErr();
 153                     break;
 154                 }
 155
 156                 error = DoIOFS(&iofs, dvp, NULL, DOSBase);
 157             } while(error == ERROR_OBJECT_NOT_FOUND && accessMode != MODE_NEWFILE);
 158
 159             if (error == ERROR_NO_MORE_ENTRIES)
 160                 error = me->pr_Result2 = ERROR_OBJECT_NOT_FOUND;
 161
 162             FreeDeviceProc(dvp);
 163         }
 164
 165         if(error == 0)
 166         {
 167             ret->fh_Device = iofs.IOFS.io_Device;
 168             ret->fh_Unit   = iofs.IOFS.io_Unit;
 169             if (doappend)
 170             {
 171                  /* See if the handler supports FSA_SEEK */
 172                  if (Seek(MKBADDR(ret), 0, OFFSET_END) != -1)
 173                  {
 174                      /* if so then set the proper flag in the FileHandle struct */
 175                      ret->fh_Flags |= FHF_APPEND;
 176                  }
 177             }
 178             if (IsInteractive(MKBADDR(ret)))
 179                 SetVBuf(MKBADDR(ret), NULL, BUF_LINE, -1);
 180
 181             return MKBADDR(ret);
 182         }
 183
 184         FreeDosObject(DOS_FILEHANDLE,ret);
 185     }
 186
 187     else
 188         SetIoErr(ERROR_NO_FREE_STORE);
 189
 190     return 0;
 191
 192     AROS_LIBFUNC_EXIT
 193 } /* Open */