/****************************************************************************
*
* fn_open
*
* open a file for reading/writing/appending
*
* INPUTS
*
* filename - which file need to be opened
* mode - string how to open ("r"-read, "w"-write, "w+"-overwrite, "a"-append
*
* RETURNS
*
* F_FILE pointer if successfully
* 0 - if any error
*
***************************************************************************/
F_FILE * fn_open ( const char * filename, const char * mode )
{
F_DIRENTRY * de;
F_NAME fsname;
unsigned short date;
unsigned short time;
unsigned char m_mode = F_FILE_CLOSE;
if ( mode[1] == 0 )
{
if ( mode[0] == 'r' )
{
m_mode = F_FILE_RD;
}
if ( mode[0] == 'w' )
{
m_mode = F_FILE_WR;
}
if ( mode[0] == 'a' )
{
m_mode = F_FILE_A;
}
}
if ( ( mode[1] == '+' ) && ( mode[2] == 0 ) )
{
if ( mode[0] == 'r' )
{
m_mode = F_FILE_RDP;
}
if ( mode[0] == 'w' )
{
m_mode = F_FILE_WRP;
}
if ( mode[0] == 'a' )
{
m_mode = F_FILE_AP;
}
}
if ( m_mode == F_FILE_CLOSE )
{
return 0; /*invalid mode*/
}
if ( _f_setfsname( filename, &fsname ) )
{
return 0; /*invalid name*/
}
if ( _f_checknamewc( fsname.filename, fsname.fileext ) )
{
return 0; /*invalid name*/
}
if ( fsname.filename[0] == '.' )
{
return 0;
}
if ( _f_getvolume() )
{
return 0; /*cant open any*/
}
if ( gl_file.mode != F_FILE_CLOSE )
{
return 0;
}
psp_memset( &gl_file, 0, 21 );
if ( !_f_findpath( &fsname, &gl_file.dirpos ) )
{
return 0;
}
switch ( m_mode )
{
case F_FILE_RDP: /*r*/
case F_FILE_RD: /*r*/
if ( !_f_findfilewc( fsname.filename, fsname.fileext, &gl_file.dirpos, &de, 0 ) )
{
return 0;
}
if ( de->attr & F_ATTR_DIR )
{
return 0; /*directory*/
}
gl_file.startcluster = _f_getdecluster( de );
if ( gl_file.startcluster )
{
_f_clustertopos( gl_file.startcluster, &gl_file.pos );
gl_file.filesize = _f_getlong( &de->filesize );
gl_file.abspos = (unsigned long) (-1 * (long) F_SECTOR_SIZE);
if ( _f_fseek( 0 ) )
{
return 0;
}
}
#if F_FILE_CHANGED_EVENT
if ( m_mode == F_FILE_RDP )
{
_f_createfullname( gl_file.filename, sizeof( gl_file.filename ), fsname.path, fsname.filename, fsname.fileext );
}
#endif
break;
case F_FILE_AP:
case F_FILE_A: /*a*/
psp_memcpy( &( gl_file.pos ), &( gl_file.dirpos ), sizeof( F_POS ) );
if ( _f_findfilewc( fsname.filename, fsname.fileext, &gl_file.dirpos, &de, 0 ) )
{
if ( de->attr & ( F_ATTR_DIR | F_ATTR_READONLY ) )
{
return 0;
}
gl_file.startcluster = _f_getdecluster( de );
gl_file.filesize = _f_getlong( &de->filesize );
if ( gl_file.startcluster )
{
_f_clustertopos( gl_file.startcluster, &gl_file.pos );
gl_file.abspos = (unsigned long) (-1 * (long) F_SECTOR_SIZE); /*forcing seek to read 1st sector! abspos=0;*/
if ( _f_fseek( (long)gl_file.filesize ) )
{
gl_file.mode = F_FILE_CLOSE;
return 0;
}
}
}
else
{
psp_memcpy( &( gl_file.dirpos ), &( gl_file.pos ), sizeof( F_POS ) );
_f_clustertopos( gl_file.dirpos.cluster, &gl_file.pos );
if ( _f_addentry( &fsname, &gl_file.dirpos, &de ) )
{
return 0; /*couldnt be added*/
}
de->attr |= F_ATTR_ARC; /*set as archiv*/
if ( _f_writeglsector( (unsigned long)-1 ) )
{
return 0;
}
}
#if F_FILE_CHANGED_EVENT
_f_createfullname( gl_file.filename, sizeof( gl_file.filename ), fsname.path, fsname.filename, fsname.fileext );
#endif
break;
case F_FILE_WR: /*w*/
case F_FILE_WRP: /*w+*/
_f_clustertopos( gl_file.dirpos.cluster, &gl_file.pos );
if ( _f_findfilewc( fsname.filename, fsname.fileext, &gl_file.pos, &de, 0 ) )
{
unsigned long cluster = _f_getdecluster( de ); /*exist*/
if ( de->attr & ( F_ATTR_DIR | F_ATTR_READONLY ) )
{
return 0;
}
psp_memcpy( &( gl_file.dirpos ), &( gl_file.pos ), sizeof( F_POS ) );
_f_setlong( de->filesize, 0 ); /*reset size;*/
de->attr |= F_ATTR_ARC; /*set as archiv*/
_f_setword( de->clusterlo, 0 ); /*no points anywhere*/
_f_setword( de->clusterhi, 0 );
if ( gl_volume.mediatype == F_FAT32_MEDIA )
{
f_igettimedate( &time, &date );
_f_setword( &de->crtdate, date ); /*if there is realtime clock then creation date could be set from*/
_f_setword( &de->crttime, time ); /*if there is realtime clock then creation time could be set from*/
_f_setword( &de->lastaccessdate, date ); /*if there is realtime clock then creation date could be set from*/
}
if ( _f_writeglsector( (unsigned long)-1 ) )
{
return 0;
}
if ( _f_removechain( cluster ) )
{
return 0; /*remove */
}
}
else
{
if ( _f_addentry( &fsname, &gl_file.dirpos, &de ) )
{
return 0; /*couldnt be added*/
}
psp_memset( &gl_file, 0, 21 );
de->attr |= F_ATTR_ARC; /*set as archiv*/
if ( _f_writeglsector( (unsigned long)-1 ) )
{
return 0;
}
}
#if F_FILE_CHANGED_EVENT
_f_createfullname( gl_file.filename, sizeof( gl_file.filename ), fsname.path, fsname.filename, fsname.fileext );
#endif
break;
default:
return 0; /*invalid mode*/
} /* switch */
if ( ( m_mode != F_FILE_RD ) && ( gl_file.startcluster == 0 ) )
{
gl_volume.fatsector = (unsigned long)-1;
if ( _f_alloccluster( &( gl_file.startcluster ) ) )
{
return 0;
}
_f_clustertopos( gl_file.startcluster, &gl_file.pos );
if ( _f_setclustervalue( gl_file.startcluster, F_CLUSTER_LAST ) )
{
return 0;
}
if ( _f_writefatsector() )
{
return 0;
}
}
gl_file.mode = m_mode; /* lock it */
return (F_FILE *)1;
} /* fn_open */
/****************************************************************************
*
* _f_emptywritebuffer
*
* empty write buffer if it contains unwritten data
*
* RETURNS
* error code or zero if successful
*
***************************************************************************/
static unsigned char _f_stepnextsector ( void )
{
unsigned char ret;
unsigned char b_alloc;
b_alloc = 0;
gl_volume.fatsector = (unsigned long)-1;
if ( gl_file.startcluster == 0 )
{
b_alloc = 1;
}
else
{
++gl_file.pos.sector;
if ( gl_file.pos.sector >= gl_file.pos.sectorend )
{
unsigned long value;
ret = _f_getclustervalue( gl_file.pos.cluster, &value );
if ( ret )
{
return ret;
}
if ( ( value >= 2 ) && ( value < F_CLUSTER_RESERVED ) ) /*we are in chain*/
{
_f_clustertopos( value, &gl_file.pos ); /*go to next cluster*/
}
else
{
b_alloc = 1;
}
}
}
if ( b_alloc != 0 )
{
unsigned long nextcluster;
ret = _f_alloccluster( &nextcluster );
if ( ret )
{
return ret;
}
ret = _f_setclustervalue( nextcluster, F_CLUSTER_LAST );
if ( ret )
{
return ret;
}
if ( gl_file.startcluster == 0 )
{
gl_file.startcluster = nextcluster;
}
else
{
ret = _f_setclustervalue( gl_file.pos.cluster, nextcluster );
if ( ret )
{
return ret;
}
}
_f_clustertopos( nextcluster, &gl_file.pos );
return _f_writefatsector();
}
return F_NO_ERROR;
} /* _f_stepnextsector */
static unsigned char _f_emptywritebuffer ( void )
{
unsigned char ret;
ret = _f_writeglsector( gl_file.pos.sector );
if ( ret )
{
return ret;
}
gl_file.modified = 0;
gl_file.pos.sector++;
if ( gl_file.pos.sector >= gl_file.pos.sectorend )
{
unsigned long value;
gl_volume.fatsector = (unsigned long)-1;
ret = _f_getclustervalue( gl_file.pos.cluster, &value );
if ( ret )
{
return ret;
}
if ( ( value >= 2 ) && ( value < F_CLUSTER_RESERVED ) ) /*we are in chain*/
{
gl_file.prevcluster = gl_file.pos.cluster;
_f_clustertopos( value, &gl_file.pos ); /*go to next cluster*/
}
else
{
unsigned long nextcluster;
ret = _f_alloccluster( &nextcluster );
if ( ret )
{
return ret;
}
ret = _f_setclustervalue( nextcluster, F_CLUSTER_LAST );
if ( ret )
{
return ret;
}
ret = _f_setclustervalue( gl_file.pos.cluster, nextcluster );
if ( ret )
{
return ret;
}
gl_file.prevcluster = gl_file.pos.cluster;
_f_clustertopos( nextcluster, &gl_file.pos );
return _f_writefatsector();
}
}
return F_NO_ERROR;
} /* _f_emptywritebuffer */