libvips/libsrc/iofuncs/im_iocheck.c
John Cupitt a82fe054e6 stuff
2008-07-07 16:42:33 +00:00

313 lines
6.2 KiB
C

/* @(#) Function which checks the structures imagein and imageout
* @(#) It returns a valid value only if ip and op are set properly
* @(#) Cases of returned integer value
* @(#)
* @(#) int im_iocheck(imagein, imageout)
* @(#) IMAGE *imagein, *imageout;
* @(#)
* @(#) Returns -1 on fail
* @(#)
*
* Copyright: Nicos Dessipris
* Written on: 12/02/1990
* Modified on :
* 15/4/93 JC
* - im_incheck(), im_outcheck() added.
* - type field now checked.
* 10/6/93 JC
* - auto-fallback to old-style input added
* 6/6/95 JC
* - revised and improved fallback code
*/
/* @(#) Try to make an IMAGE writeable. im_mmapin files become im_mmapinrw
* @(#) files, buffers are left alone and output files and partial images
* @(#) generate an error.
* @(#)
* @(#) int im_rwcheck( im )
* @(#) IMAGE *im;
* @(#)
* @(#) Returns non-zero on error.
* @(#)
* Copyright: John Cupitt
* Written on: 17/6/92
* Updated on:
* 15/4/93
* - checks for partial images added
* - now uses type field
* 31/8/93 JC
* - returns ok for IM_MMAPINRW type files now too
* - returns -1 rather than 1 on error
* - ANSIfied
* 1/10/97 JC
* - moved here, and renamed im_rwcheck()
* 13/2/01 JC
* - im_image_sanity() checks added
*/
/*
This file is part of VIPS.
VIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif /*HAVE_UNISTD_H*/
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_SYS_FILE_H
#include <sys/file.h>
#endif /*HAVE_SYS_FILE_H*/
#include <vips/vips.h>
#include <vips/internal.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Convert a partial to a setbuf.
*/
static int
convert_ptob( IMAGE *im )
{
IMAGE *t1;
/* Change to IM_SETBUF. First, make a memory buffer and copy into that.
*/
if( !(t1 = im_open( "im_incheck:1", "t" )) )
return( -1 );
if( im_copy( im, t1 ) ) {
im_close( t1 );
return( -1 );
}
/* Copy new stuff in. We can't im__close( im ) and free stuff, as this
* would kill of lots of regions and cause dangling pointers
* elsewhere.
*/
im->dtype = IM_SETBUF;
im->data = t1->data;
t1->data = NULL;
/* Close temp image.
*/
if( im_close( t1 ) )
return( -1 );
return( 0 );
}
/* Convert an openin to a mmapin.
*/
static int
convert_otom( IMAGE *im )
{
/* just mmap() the whole thing.
*/
if( im_mapfile( im ) )
return( -1 );
im->data = im->baseaddr + im->sizeof_header;
im->dtype = IM_MMAPIN;
return( 0 );
}
/* Check that an image is readable by old-style VIPS functions.
*/
int
im_incheck( IMAGE *im )
{
im_image_sanity( im );
#ifdef DEBUG_IO
printf( "im_incheck: old-style input for %s\n", im->filename );
#endif/*DEBUG_IO*/
switch( im->dtype ) {
case IM_SETBUF:
case IM_SETBUF_FOREIGN:
/* Should have been written to.
*/
if( !im->data ) {
im_errormsg( "im_incheck: no image data" );
return( -1 );
}
break;
case IM_MMAPIN:
case IM_MMAPINRW:
/* Can read from all these, in principle anyway.
*/
break;
case IM_PARTIAL:
#ifdef DEBUG_IO
printf( "im_incheck: converting partial image to WIO\n" );
#endif/*DEBUG_IO*/
/* Change to a setbuf, so our caller can use it.
*/
if( convert_ptob( im ) )
return( -1 );
break;
case IM_OPENIN:
#ifdef DEBUG_IO
printf( "im_incheck: converting openin image for old-style input\n" );
#endif/*DEBUG_IO*/
/* Change to a MMAPIN.
*/
if( convert_otom( im ) )
return( -1 );
break;
case IM_OPENOUT:
/* Close file down and reopen as im_mmapin.
*/
#ifdef DEBUG_IO
printf( "im_incheck: auto-rewind of %s\n", im->filename );
#endif/*DEBUG_IO*/
if( im__close( im ) || im_openin( im ) ) {
im_errormsg( "im_incheck: auto-rewind for %s failed",
im->filename );
return( -1 );
}
break;
default:
im_errormsg( "im_incheck: image not readable" );
return( -1 );
}
return( 0 );
}
/* Check that an image is writeable.
*/
int
im_outcheck( IMAGE *im )
{
#ifdef DEBUG_IO
printf( "im_outcheck: old-style output for %s\n", im->filename );
#endif/*DEBUG_IO*/
switch( im->dtype ) {
case IM_PARTIAL:
/* Make sure nothing is attached.
*/
if( im->generate ) {
im_errormsg( "im_outcheck: image already written" );
return( -1 );
}
/* Cannot do old-style write to PARTIAL. Turn to SETBUF.
*/
im->dtype = IM_SETBUF;
/* Fall through to SETBUF case.
*/
case IM_SETBUF:
/* Check that it has not been im_setupout().
*/
if( im->data ) {
im_errormsg( "im_outcheck: image already written" );
return( -1 );
}
break;
case IM_OPENOUT:
case IM_SETBUF_FOREIGN:
/* Can write to this ok.
*/
break;
default:
im_errormsg( "im_outcheck: image not writeable" );
return( -1 );
}
return( 0 );
}
/* Check a pair of fds for IO.
*/
int
im_iocheck( IMAGE *in, IMAGE *out )
{
return( im_incheck( in ) || im_outcheck( out ) );
}
int
im_rwcheck( IMAGE *im )
{
/* Do an im_incheck(). This will rewind im_openout() files, and
* generate im_partial() files.
*/
if( im_incheck( im ) ) {
im_errormsg( "im_rwcheck: unable to rewind file" );
return( -1 );
}
/* Look at the type.
*/
switch( im->dtype ) {
case IM_SETBUF:
case IM_SETBUF_FOREIGN:
case IM_MMAPINRW:
/* No action necessary.
*/
break;
case IM_MMAPIN:
/* Try to remap read-write.
*/
if( im_remapfilerw( im ) )
return( -1 );
break;
default:
im_errormsg( "im_rwcheck: bad file type" );
return( -1 );
}
return( 0 );
}