sfsize.c revision 34f9b3eef6fdadbda0a846aa4d68691ac40eace5
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1985-2009 AT&T Intellectual Property *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.opensource.org/licenses/cpl1.0.txt *
* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* Phong Vo <kpv@research.att.com> *
* *
***********************************************************************/
#include "sfhdr.h"
/* Get the size of a stream.
**
** Written by Kiem-Phong Vo.
*/
#if __STD_C
Sfoff_t sfsize(Sfio_t* f)
#else
Sfoff_t sfsize(f)
Sfio_t* f;
#endif
{
Sfdisc_t* disc;
reg int mode;
Sfoff_t s;
SFMTXDECL(f);
SFMTXENTER(f, (Sfoff_t)(-1));
if((mode = f->mode&SF_RDWR) != (int)f->mode && _sfmode(f,mode,0) < 0)
SFMTXRETURN(f, (Sfoff_t)(-1));
if(f->flags&SF_STRING)
{ SFSTRSIZE(f);
SFMTXRETURN(f, f->extent);
}
SFLOCK(f,0);
s = f->here;
if(f->extent >= 0)
{ if(f->flags&(SF_SHARE|SF_APPENDWR))
{ for(disc = f->disc; disc; disc = disc->disc)
if(disc->seekf)
break;
if(!_sys_stat || disc)
{ Sfoff_t e;
if((e = SFSK(f,0,SEEK_END,disc)) >= 0)
f->extent = e;
if(SFSK(f,f->here,SEEK_SET,disc) != f->here)
f->here = SFSK(f,(Sfoff_t)0,SEEK_CUR,disc);
}
#if _sys_stat
else
{ sfstat_t st;
if(sysfstatf(f->file,&st) < 0)
f->extent = -1;
else if((f->extent = st.st_size) < f->here)
f->here = SFSK(f,(Sfoff_t)0,SEEK_CUR,disc);
}
#endif
}
if((f->flags&(SF_SHARE|SF_PUBLIC)) == (SF_SHARE|SF_PUBLIC))
f->here = SFSK(f,(Sfoff_t)0,SEEK_CUR,f->disc);
}
if(f->here != s && (f->mode&SF_READ) )
{ /* buffered data is known to be invalid */
#ifdef MAP_TYPE
if((f->bits&SF_MMAP) && f->data)
{ SFMUNMAP(f,f->data,f->endb-f->data);
f->data = NIL(uchar*);
}
#endif
f->next = f->endb = f->endr = f->endw = f->data;
}
if(f->here < 0)
f->extent = -1;
else if(f->extent < f->here)
f->extent = f->here;
if((s = f->extent) >= 0)
{ if(f->flags&SF_APPENDWR)
s += (f->next - f->data);
else if(f->mode&SF_WRITE)
{ s = f->here + (f->next - f->data);
if(s < f->extent)
s = f->extent;
}
}
SFOPEN(f,0);
SFMTXRETURN(f, s);
}