| /* $Id: tif_stream.cxx,v 1.22 2009/09/06 13:11:29 drolon Exp $ */ |
| |
| /* |
| * Copyright (c) 1988-1996 Sam Leffler |
| * Copyright (c) 1991-1996 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 UNIX-specific Routines. |
| */ |
| #include "tiffiop.h" |
| #include <iostream> |
| |
| #ifndef __VMS |
| using namespace std; |
| #endif |
| |
| class tiffis_data |
| { |
| public: |
| |
| istream *myIS; |
| long myStreamStartPos; |
| }; |
| |
| class tiffos_data |
| { |
| public: |
| |
| ostream *myOS; |
| long myStreamStartPos; |
| }; |
| |
| static tsize_t |
| _tiffosReadProc(thandle_t, tdata_t, tsize_t) |
| { |
| return 0; |
| } |
| |
| static tsize_t |
| _tiffisReadProc(thandle_t fd, tdata_t buf, tsize_t size) |
| { |
| tiffis_data *data = (tiffis_data *)fd; |
| |
| data->myIS->read((char *)buf, (int)size); |
| |
| return data->myIS->gcount(); |
| } |
| |
| static tsize_t |
| _tiffosWriteProc(thandle_t fd, tdata_t buf, tsize_t size) |
| { |
| tiffos_data *data = (tiffos_data *)fd; |
| ostream *os = data->myOS; |
| int pos = os->tellp(); |
| |
| os->write((const char *)buf, size); |
| |
| return ((int)os->tellp()) - pos; |
| } |
| |
| static tsize_t |
| _tiffisWriteProc(thandle_t, tdata_t, tsize_t) |
| { |
| return 0; |
| } |
| |
| static toff_t |
| _tiffosSeekProc(thandle_t fd, toff_t off, int whence) |
| { |
| tiffos_data *data = (tiffos_data *)fd; |
| ostream *os = data->myOS; |
| |
| // if the stream has already failed, don't do anything |
| if( os->fail() ) |
| return os->tellp(); |
| |
| switch(whence) { |
| case SEEK_SET: |
| os->seekp(data->myStreamStartPos + off, ios::beg); |
| break; |
| case SEEK_CUR: |
| os->seekp(off, ios::cur); |
| break; |
| case SEEK_END: |
| os->seekp(off, ios::end); |
| break; |
| } |
| |
| // Attempt to workaround problems with seeking past the end of the |
| // stream. ofstream doesn't have a problem with this but |
| // ostrstream/ostringstream does. In that situation, add intermediate |
| // '\0' characters. |
| if( os->fail() ) { |
| #ifdef __VMS |
| int old_state; |
| #else |
| ios::iostate old_state; |
| #endif |
| toff_t origin=0; |
| |
| old_state = os->rdstate(); |
| // reset the fail bit or else tellp() won't work below |
| os->clear(os->rdstate() & ~ios::failbit); |
| switch( whence ) { |
| case SEEK_SET: |
| origin = data->myStreamStartPos; |
| break; |
| case SEEK_CUR: |
| origin = os->tellp(); |
| break; |
| case SEEK_END: |
| os->seekp(0, ios::end); |
| origin = os->tellp(); |
| break; |
| } |
| // restore original stream state |
| os->clear(old_state); |
| |
| // only do something if desired seek position is valid |
| if( origin + off > data->myStreamStartPos ) { |
| toff_t num_fill; |
| |
| // clear the fail bit |
| os->clear(os->rdstate() & ~ios::failbit); |
| |
| // extend the stream to the expected size |
| os->seekp(0, ios::end); |
| num_fill = origin + off - (toff_t)os->tellp(); |
| for( toff_t i = 0; i < num_fill; i++ ) |
| os->put('\0'); |
| |
| // retry the seek |
| os->seekp(origin + off, ios::beg); |
| } |
| } |
| |
| return os->tellp(); |
| } |
| |
| static toff_t |
| _tiffisSeekProc(thandle_t fd, toff_t off, int whence) |
| { |
| tiffis_data *data = (tiffis_data *)fd; |
| |
| switch(whence) { |
| case SEEK_SET: |
| data->myIS->seekg(data->myStreamStartPos + off, ios::beg); |
| break; |
| case SEEK_CUR: |
| data->myIS->seekg(off, ios::cur); |
| break; |
| case SEEK_END: |
| data->myIS->seekg(off, ios::end); |
| break; |
| } |
| |
| return ((long)data->myIS->tellg()) - data->myStreamStartPos; |
| } |
| |
| static toff_t |
| _tiffosSizeProc(thandle_t fd) |
| { |
| tiffos_data *data = (tiffos_data *)fd; |
| ostream *os = data->myOS; |
| toff_t pos = os->tellp(); |
| toff_t len; |
| |
| os->seekp(0, ios::end); |
| len = os->tellp(); |
| os->seekp(pos); |
| |
| return len; |
| } |
| |
| static toff_t |
| _tiffisSizeProc(thandle_t fd) |
| { |
| tiffis_data *data = (tiffis_data *)fd; |
| int pos = data->myIS->tellg(); |
| int len; |
| |
| data->myIS->seekg(0, ios::end); |
| len = data->myIS->tellg(); |
| data->myIS->seekg(pos); |
| |
| return len; |
| } |
| |
| static int |
| _tiffosCloseProc(thandle_t fd) |
| { |
| // Our stream was not allocated by us, so it shouldn't be closed by us. |
| delete (tiffos_data *)fd; |
| return 0; |
| } |
| |
| static int |
| _tiffisCloseProc(thandle_t fd) |
| { |
| // Our stream was not allocated by us, so it shouldn't be closed by us. |
| delete (tiffis_data *)fd; |
| return 0; |
| } |
| |
| static int |
| _tiffDummyMapProc(thandle_t , tdata_t* , toff_t* ) |
| { |
| return (0); |
| } |
| |
| static void |
| _tiffDummyUnmapProc(thandle_t , tdata_t , toff_t ) |
| { |
| } |
| |
| /* |
| * Open a TIFF file descriptor for read/writing. |
| */ |
| static TIFF* |
| _tiffStreamOpen(const char* name, const char* mode, void *fd) |
| { |
| TIFF* tif; |
| |
| if( strchr(mode, 'w') ) { |
| tiffos_data *data = new tiffos_data; |
| data->myOS = (ostream *)fd; |
| data->myStreamStartPos = data->myOS->tellp(); |
| |
| // Open for writing. |
| tif = TIFFClientOpen(name, mode, |
| (thandle_t) data, |
| _tiffosReadProc, _tiffosWriteProc, |
| _tiffosSeekProc, _tiffosCloseProc, |
| _tiffosSizeProc, |
| _tiffDummyMapProc, _tiffDummyUnmapProc); |
| } else { |
| tiffis_data *data = new tiffis_data; |
| data->myIS = (istream *)fd; |
| data->myStreamStartPos = data->myIS->tellg(); |
| // Open for reading. |
| tif = TIFFClientOpen(name, mode, |
| (thandle_t) data, |
| _tiffisReadProc, _tiffisWriteProc, |
| _tiffisSeekProc, _tiffisCloseProc, |
| _tiffisSizeProc, |
| _tiffDummyMapProc, _tiffDummyUnmapProc); |
| } |
| |
| return (tif); |
| } |
| |
| TIFF* |
| TIFFStreamOpen(const char* name, ostream *os) |
| { |
| // If os is either a ostrstream or ostringstream, and has no data |
| // written to it yet, then tellp() will return -1 which will break us. |
| // We workaround this by writing out a dummy character and |
| // then seek back to the beginning. |
| if( !os->fail() && (int)os->tellp() < 0 ) { |
| *os << '\0'; |
| os->seekp(0); |
| } |
| |
| // NB: We don't support mapped files with streams so add 'm' |
| return _tiffStreamOpen(name, "wm", os); |
| } |
| |
| TIFF* |
| TIFFStreamOpen(const char* name, istream *is) |
| { |
| // NB: We don't support mapped files with streams so add 'm' |
| return _tiffStreamOpen(name, "rm", is); |
| } |
| |
| /* vim: set ts=8 sts=8 sw=8 noet: */ |