1N/A/***********************************************************************
1N/A* *
1N/A* This software is part of the ast package *
1N/A* Copyright (c) 1985-2011 AT&T Intellectual Property *
1N/A* and is licensed under the *
1N/A* Common Public License, Version 1.0 *
1N/A* by AT&T Intellectual Property *
1N/A* *
1N/A* A copy of the License is available at *
1N/A* http://www.opensource.org/licenses/cpl1.0.txt *
1N/A* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
1N/A* *
1N/A* Information and Software Systems Research *
1N/A* AT&T Research *
1N/A* Florham Park NJ *
1N/A* *
1N/A* Glenn Fowler <gsf@research.att.com> *
1N/A* David Korn <dgk@research.att.com> *
1N/A* Phong Vo <kpv@research.att.com> *
1N/A* *
1N/A***********************************************************************/
1N/A#include "sfhdr.h"
1N/A
1N/A/* Swap two streams. If the second argument is NULL,
1N/A** a new stream will be created. Always return the second argument
1N/A** or the new stream. Note that this function will always work
1N/A** unless streams are locked by SF_PUSH.
1N/A**
1N/A** Written by Kiem-Phong Vo.
1N/A*/
1N/A
1N/A#if __STD_C
1N/ASfio_t* sfswap(reg Sfio_t* f1, reg Sfio_t* f2)
1N/A#else
1N/ASfio_t* sfswap(f1,f2)
1N/Areg Sfio_t* f1;
1N/Areg Sfio_t* f2;
1N/A#endif
1N/A{
1N/A Sfio_t tmp;
1N/A int f1pool, f2pool, f1mode, f2mode, f1flags, f2flags;
1N/A
1N/A if(!f1 || (f1->mode&SF_AVAIL) || (SFFROZEN(f1) && (f1->mode&SF_PUSH)) )
1N/A return NIL(Sfio_t*);
1N/A if(f2 && SFFROZEN(f2) && (f2->mode&SF_PUSH) )
1N/A return NIL(Sfio_t*);
1N/A if(f1 == f2)
1N/A return f2;
1N/A
1N/A f1mode = f1->mode;
1N/A SFLOCK(f1,0);
1N/A f1->mode |= SF_PUSH; /* make sure there is no recursion on f1 */
1N/A
1N/A if(f2)
1N/A { f2mode = f2->mode;
1N/A SFLOCK(f2,0);
1N/A f2->mode |= SF_PUSH; /* make sure there is no recursion on f2 */
1N/A }
1N/A else
1N/A { f2 = f1->file == 0 ? sfstdin :
1N/A f1->file == 1 ? sfstdout :
1N/A f1->file == 2 ? sfstderr : NIL(Sfio_t*);
1N/A if((!f2 || !(f2->mode&SF_AVAIL)) )
1N/A { if(!(f2 = (Sfio_t*)malloc(sizeof(Sfio_t))) )
1N/A { f1->mode = f1mode;
1N/A SFOPEN(f1,0);
1N/A return NIL(Sfio_t*);
1N/A }
1N/A
1N/A SFCLEAR(f2,NIL(Vtmutex_t*));
1N/A }
1N/A f2->mode = SF_AVAIL|SF_LOCK;
1N/A f2mode = SF_AVAIL;
1N/A }
1N/A
1N/A if(!f1->pool)
1N/A f1pool = -1;
1N/A else for(f1pool = f1->pool->n_sf-1; f1pool >= 0; --f1pool)
1N/A if(f1->pool->sf[f1pool] == f1)
1N/A break;
1N/A if(!f2->pool)
1N/A f2pool = -1;
1N/A else for(f2pool = f2->pool->n_sf-1; f2pool >= 0; --f2pool)
1N/A if(f2->pool->sf[f2pool] == f2)
1N/A break;
1N/A
1N/A f1flags = f1->flags;
1N/A f2flags = f2->flags;
1N/A
1N/A /* swap image and pool entries */
1N/A memcpy((Void_t*)(&tmp),(Void_t*)f1,sizeof(Sfio_t));
1N/A memcpy((Void_t*)f1,(Void_t*)f2,sizeof(Sfio_t));
1N/A memcpy((Void_t*)f2,(Void_t*)(&tmp),sizeof(Sfio_t));
1N/A if(f2pool >= 0)
1N/A f1->pool->sf[f2pool] = f1;
1N/A if(f1pool >= 0)
1N/A f2->pool->sf[f1pool] = f2;
1N/A
1N/A if(f2flags&SF_STATIC)
1N/A f2->flags |= SF_STATIC;
1N/A else f2->flags &= ~SF_STATIC;
1N/A
1N/A if(f1flags&SF_STATIC)
1N/A f1->flags |= SF_STATIC;
1N/A else f1->flags &= ~SF_STATIC;
1N/A
1N/A if(f2mode&SF_AVAIL) /* swapping to a closed stream */
1N/A { if(!(f1->flags&SF_STATIC) )
1N/A free(f1);
1N/A }
1N/A else
1N/A { f1->mode = f2mode;
1N/A SFOPEN(f1,0);
1N/A }
1N/A
1N/A f2->mode = f1mode;
1N/A SFOPEN(f2,0);
1N/A return f2;
1N/A}