/* $Header: /cvsroot/osrs/libtiff/libtiff/tif_open.c,v 1.6 2001/07/20 02:22:46 warmerda Exp $ */
/*
* Copyright (c) 1988-1997 Sam Leffler
* Copyright (c) 1991-1997 Silicon Graphics, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software and
* its documentation for any purpose is hereby granted without fee, provided
* that (i) the above copyright notices and this permission notice appear in
* all copies of the software and related documentation, and (ii) the names of
* Sam Leffler and Silicon Graphics may not be used in any advertising or
* publicity relating to the software without the specific, prior written
* permission of Sam Leffler and Silicon Graphics.
*
* THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
* EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
* WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
*
* IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
* WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
* LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
/*
* TIFF Library.
*/
#include "tiffiop.h"
void _TIFFSetDefaultCompressionState(TIFF* tif);
static const long typemask[13] = {
0L, /* TIFF_NOTYPE */
0x000000ffL, /* TIFF_BYTE */
0xffffffffL, /* TIFF_ASCII */
0x0000ffffL, /* TIFF_SHORT */
0xffffffffL, /* TIFF_LONG */
0xffffffffL, /* TIFF_RATIONAL */
0x000000ffL, /* TIFF_SBYTE */
0x000000ffL, /* TIFF_UNDEFINED */
0x0000ffffL, /* TIFF_SSHORT */
0xffffffffL, /* TIFF_SLONG */
0xffffffffL, /* TIFF_SRATIONAL */
0xffffffffL, /* TIFF_FLOAT */
0xffffffffL, /* TIFF_DOUBLE */
};
static const int bigTypeshift[13] = {
0, /* TIFF_NOTYPE */
24, /* TIFF_BYTE */
0, /* TIFF_ASCII */
16, /* TIFF_SHORT */
0, /* TIFF_LONG */
0, /* TIFF_RATIONAL */
24, /* TIFF_SBYTE */
24, /* TIFF_UNDEFINED */
16, /* TIFF_SSHORT */
0, /* TIFF_SLONG */
0, /* TIFF_SRATIONAL */
0, /* TIFF_FLOAT */
0, /* TIFF_DOUBLE */
};
static const int litTypeshift[13] = {
0, /* TIFF_NOTYPE */
0, /* TIFF_BYTE */
0, /* TIFF_ASCII */
0, /* TIFF_SHORT */
0, /* TIFF_LONG */
0, /* TIFF_RATIONAL */
0, /* TIFF_SBYTE */
0, /* TIFF_UNDEFINED */
0, /* TIFF_SSHORT */
0, /* TIFF_SLONG */
0, /* TIFF_SRATIONAL */
0, /* TIFF_FLOAT */
0, /* TIFF_DOUBLE */
};
/*
* Initialize the shift & mask tables, and the
* byte swapping state according to the file
* contents and the machine architecture.
*/
static void
TIFFInitOrder(TIFF* tif, int magic, int bigendian)
{
tif->tif_typemask = typemask;
if (magic == TIFF_BIGENDIAN) {
tif->tif_typeshift = bigTypeshift;
if (!bigendian)
tif->tif_flags |= TIFF_SWAB;
} else {
tif->tif_typeshift = litTypeshift;
if (bigendian)
tif->tif_flags |= TIFF_SWAB;
}
}
int
_TIFFgetMode(const char* mode, const char* module)
{
int m = -1;
switch (mode[0]) {
case 'r':
m = O_RDONLY;
if (mode[1] == '+')
m = O_RDWR;
break;
case 'w':
case 'a':
m = O_RDWR|O_CREAT;
if (mode[0] == 'w')
m |= O_TRUNC;
break;
default:
TIFFError(module, "\"%s\": Bad mode", mode);
break;
}
return (m);
}
TIFF*
TIFFClientOpen(
const char* name, const char* mode,
thandle_t clientdata,
TIFFReadWriteProc readproc,
TIFFReadWriteProc writeproc,
TIFFSeekProc seekproc,
TIFFCloseProc closeproc,
TIFFSizeProc sizeproc,
TIFFMapFileProc mapproc,
TIFFUnmapFileProc unmapproc
)
{
static const char module[] = "TIFFClientOpen";
TIFF *tif;
int m, bigendian;
const char* cp;
m = _TIFFgetMode(mode, module);
if (m == -1)
goto bad2;
tif = (TIFF *)_TIFFmalloc(sizeof (TIFF) + strlen(name) + 1);
if (tif == NULL) {
TIFFError(module, "%s: Out of memory (TIFF structure)", name);
goto bad2;
}
_TIFFmemset(tif, 0, sizeof (*tif));
tif->tif_name = (char *)tif + sizeof (TIFF);
strcpy(tif->tif_name, name);
tif->tif_mode = m &~ (O_CREAT|O_TRUNC);
tif->tif_curdir = (tdir_t) -1; /* non-existent directory */
tif->tif_curoff = 0;
tif->tif_curstrip = (tstrip_t) -1; /* invalid strip */
tif->tif_row = (uint32) -1; /* read/write pre-increment */
tif->tif_clientdata = clientdata;
tif->tif_readproc = readproc;
tif->tif_writeproc = writeproc;
tif->tif_seekproc = seekproc;
tif->tif_closeproc = closeproc;
tif->tif_sizeproc = sizeproc;
tif->tif_mapproc = mapproc;
tif->tif_unmapproc = unmapproc;
_TIFFSetDefaultCompressionState(tif); /* setup default state */
/*
* Default is to return data MSB2LSB and enable the
* use of memory-mapped files and strip chopping when
* a file is opened read-only.
*/
tif->tif_flags = FILLORDER_MSB2LSB;
if (m == O_RDONLY )
tif->tif_flags |= TIFF_MAPPED;
#ifdef STRIPCHOP_DEFAULT
if (m == O_RDONLY || m == O_RDWR)
tif->tif_flags |= STRIPCHOP_DEFAULT;
#endif
{ union { int32 i; char c[4]; } u; u.i = 1; bigendian = u.c[0] == 0; }
/*
* Process library-specific flags in the open mode string.
* The following flags may be used to control intrinsic library
* behaviour that may or may not be desirable (usually for
* compatibility with some application that claims to support
* TIFF but only supports some braindead idea of what the
* vendor thinks TIFF is):
*
* 'l' use little-endian byte order for creating a file
* 'b' use big-endian byte order for creating a file
* 'L' read/write information using LSB2MSB bit order
* 'B' read/write information using MSB2LSB bit order
* 'H' read/write information using host bit order
* 'M' enable use of memory-mapped files when supported
* 'm' disable use of memory-mapped files
* 'C' enable strip chopping support when reading
* 'c' disable strip chopping support
*
* The use of the 'l' and 'b' flags is strongly discouraged.
* These flags are provided solely because numerous vendors,
* typically on the PC, do not correctly support TIFF; they
* only support the Intel little-endian byte order. This
* support is not configured by default because it supports
* the violation of the TIFF spec that says that readers *MUST*
* support both byte orders. It is strongly recommended that
* you not use this feature except to deal with busted apps
* that write invalid TIFF. And even in those cases you should
* bang on the vendors to fix their software.
*
* The 'L', 'B', and 'H' flags are intended for applications
* that can optimize operations on data by using a particular
* bit order. By default the library returns data in MSB2LSB
* bit order for compatibiltiy with older versions of this
* library. Returning data in the bit order of the native cpu
* makes the most sense but also requires applications to check
* the value of the FillOrder tag; something they probabyl do
* not do right now.
*
* The 'M' and 'm' flags are provided because some virtual memory
* systems exhibit poor behaviour when large images are mapped.
* These options permit clients to control the use of memory-mapped
* files on a per-file basis.
*
* The 'C' and 'c' flags are provided because the library support
* for chopping up large strips into multiple smaller strips is not
* application-transparent and as such can cause problems. The 'c'
* option permits applications that only want to look at the tags,
* for example, to get the unadulterated TIFF tag information.
*/
for (cp = mode; *cp; cp++)
switch (*cp) {
case 'b':
if ((m&O_CREAT) && !bigendian)
tif->tif_flags |= TIFF_SWAB;
break;
case 'l':
if ((m&O_CREAT) && bigendian)
tif->tif_flags |= TIFF_SWAB;
break;
case 'B':
tif->tif_flags = (tif->tif_flags &~ TIFF_FILLORDER) |
FILLORDER_MSB2LSB;
break;
case 'L':
tif->tif_flags = (tif->tif_flags &~ TIFF_FILLORDER) |
FILLORDER_LSB2MSB;
break;
case 'H':
tif->tif_flags = (tif->tif_flags &~ TIFF_FILLORDER) |
HOST_FILLORDER;
break;
case 'M':
if (m == O_RDONLY)
tif->tif_flags |= TIFF_MAPPED;
break;
case 'm':
if (m == O_RDONLY)
tif->tif_flags &= ~TIFF_MAPPED;
break;
case 'C':
if (m == O_RDONLY)
tif->tif_flags |= TIFF_STRIPCHOP;
break;
case 'c':
if (m == O_RDONLY)
tif->tif_flags &= ~TIFF_STRIPCHOP;
break;
}
/*
* Read in TIFF header.
*/
if (!ReadOK(tif, &tif->tif_header, sizeof (TIFFHeader))) {
if (tif->tif_mode == O_RDONLY) {
TIFFError(name, "Cannot read TIFF header");
goto bad;
}
/*
* Setup header and write.
*/
tif->tif_header.tiff_magic = tif->tif_flags & TIFF_SWAB
? (bigendian ? TIFF_LITTLEENDIAN : TIFF_BIGENDIAN)
: (bigendian ? TIFF_BIGENDIAN : TIFF_LITTLEENDIAN);
tif->tif_header.tiff_version = TIFF_VERSION;
if (tif->tif_flags & TIFF_SWAB)
TIFFSwabShort(&tif->tif_header.tiff_version);
tif->tif_header.tiff_diroff = 0; /* filled in later */
/*
* This seek shouldn't be necessary, but I have had some
* crazy problems with a failed fseek() on Solaris leaving
* the current file pointer out of whack when an fwrite()
* is done.
*/
TIFFSeekFile( tif, 0, SEEK_SET );
if (!WriteOK(tif, &tif->tif_header, sizeof (TIFFHeader))) {
TIFFError(name, "Error writing TIFF header");
goto bad;
}
/*
* Setup the byte order handling.
*/
TIFFInitOrder(tif, tif->tif_header.tiff_magic, bigendian);
/*
* Setup default directory.
*/
if (!TIFFDefaultDirectory(tif))
goto bad;
tif->tif_diroff = 0;
return (tif);
}
/*
* Setup the byte order handling.
*/
if (tif->tif_header.tiff_magic != TIFF_BIGENDIAN &&
tif->tif_header.tiff_magic != TIFF_LITTLEENDIAN) {
TIFFError(name, "Not a TIFF file, bad magic number %d (0x%x)",
tif->tif_header.tiff_magic,
tif->tif_header.tiff_magic);
goto bad;
}
TIFFInitOrder(tif, tif->tif_header.tiff_magic, bigendian);
/*
* Swap header if required.
*/
if (tif->tif_flags & TIFF_SWAB) {
TIFFSwabShort(&tif->tif_header.tiff_version);
TIFFSwabLong(&tif->tif_header.tiff_diroff);
}
/*
* Now check version (if needed, it's been byte-swapped).
* Note that this isn't actually a version number, it's a
* magic number that doesn't change (stupid).
*/
if (tif->tif_header.tiff_version != TIFF_VERSION) {
TIFFError(name,
"Not a TIFF file, bad version number %d (0x%x)",
tif->tif_header.tiff_version,
tif->tif_header.tiff_version);
goto bad;
}
tif->tif_flags |= TIFF_MYBUFFER;
tif->tif_rawcp = tif->tif_rawdata = 0;
tif->tif_rawdatasize = 0;
/*
* Setup initial directory.
*/
switch (mode[0]) {
case 'r':
tif->tif_nextdiroff = tif->tif_header.tiff_diroff;
/*
* Try to use a memory-mapped file if the client
* has not explicitly suppressed usage with the
* 'm' flag in the open mode (see above).
*/
if ((tif->tif_flags & TIFF_MAPPED) &&
!TIFFMapFileContents(tif, (tdata_t*) &tif->tif_base, &tif->tif_size))
tif->tif_flags &= ~TIFF_MAPPED;
if (TIFFReadDirectory(tif)) {
if( m != O_RDONLY
&& tif->tif_dir.td_compression != COMPRESSION_NONE )
{
TIFFError( name,
"Can't open a compressed TIFF file"
" with compression for update." );
goto bad;
}
tif->tif_rawcc = -1;
tif->tif_flags |= TIFF_BUFFERSETUP;
return (tif);
}
break;
case 'a':
/*
* New directories are automatically append
* to the end of the directory chain when they
* are written out (see TIFFWriteDirectory).
*/
if (!TIFFDefaultDirectory(tif))
goto bad;
return (tif);
}
bad:
tif->tif_mode = O_RDONLY; /* XXX avoid flush */
TIFFClose(tif);
return ((TIFF*)0);
bad2:
(void) (*closeproc)(clientdata);
return ((TIFF*)0);
}
/*
* Query functions to access private data.
*/
/*
* Return open file's name.
*/
const char *
TIFFFileName(TIFF* tif)
{
return (tif->tif_name);
}
/*
* Return open file's I/O descriptor.
*/
int
TIFFFileno(TIFF* tif)
{
return (tif->tif_fd);
}
/*
* Return read/write mode.
*/
int
TIFFGetMode(TIFF* tif)
{
return (tif->tif_mode);
}
/*
* Return nonzero if file is organized in
* tiles; zero if organized as strips.
*/
int
TIFFIsTiled(TIFF* tif)
{
return (isTiled(tif));
}
/*
* Return current row being read/written.
*/
uint32
TIFFCurrentRow(TIFF* tif)
{
return (tif->tif_row);
}
/*
* Return index of the current directory.
*/
tdir_t
TIFFCurrentDirectory(TIFF* tif)
{
return (tif->tif_curdir);
}
/*
* Return current strip.
*/
tstrip_t
TIFFCurrentStrip(TIFF* tif)
{
return (tif->tif_curstrip);
}
/*
* Return current tile.
*/
ttile_t
TIFFCurrentTile(TIFF* tif)
{
return (tif->tif_curtile);
}
/*
* Return nonzero if the file has byte-swapped data.
*/
int
TIFFIsByteSwapped(TIFF* tif)
{
return ((tif->tif_flags & TIFF_SWAB) != 0);
}
/*
* Return nonzero if the data is returned up-sampled.
*/
int
TIFFIsUpSampled(TIFF* tif)
{
return (isUpSampled(tif));
}
/*
* Return nonzero if the data is returned in MSB-to-LSB bit order.
*/
int
TIFFIsMSB2LSB(TIFF* tif)
{
return (isFillOrder(tif, FILLORDER_MSB2LSB));
}
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