common/sfio/sfnew.c

da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin/***********************************************************************
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                                                                      *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*               This software is part of the ast package               *
3e14f97f673e8a630f076077de35afdd43dc1587Roger A. Faulkner*          Copyright (c) 1985-2010 AT&T Intellectual Property          *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                      and is licensed under the                       *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                  Common Public License, Version 1.0                  *
7c2fbfb345896881c631598ee3852ce9ce33fb07April Chin*                    by AT&T Intellectual Property                     *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                                                                      *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                A copy of the License is available at                 *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*            http://www.opensource.org/licenses/cpl1.0.txt             *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                                                                      *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*              Information and Software Systems Research               *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                            AT&T Research                             *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                           Florham Park NJ                            *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                                                                      *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                 Glenn Fowler <gsf@research.att.com>                  *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                  David Korn <dgk@research.att.com>                   *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                   Phong Vo <kpv@research.att.com>                    *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*                                                                      *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin***********************************************************************/
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#include    "sfhdr.h"
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin/*  Fundamental function to create a new stream.
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin**  The argument flags defines the type of stream and the scheme
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin**  of buffering.
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin**
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin**  Written by Kiem-Phong Vo.
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin*/
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#if __STD_C
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinSfio_t* sfnew(Sfio_t* oldf, Void_t* buf, size_t size, int file, int flags)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#else
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinSfio_t* sfnew(oldf,buf,size,file,flags)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinSfio_t* oldf;   /* old stream to be reused */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinVoid_t* buf;    /* a buffer to read/write, if NULL, will be allocated */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinsize_t  size;   /* buffer size if buf is given or desired buffer size */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinint file;   /* file descriptor to read/write from */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinint flags;  /* type of file stream */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#endif
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin{
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    reg Sfio_t* f;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    reg int     sflags;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    SFONCE();   /* initialize mutexes */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    if(!(flags&SF_RDWR))
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        return NIL(Sfio_t*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    sflags = 0;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    if((f = oldf) )
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    {   if(flags&SF_EOF)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        {   if(f != sfstdin && f != sfstdout && f != sfstderr)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                f->mutex = NIL(Vtmutex_t*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            SFCLEAR(f, f->mutex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            oldf = NIL(Sfio_t*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        else if(f->mode&SF_AVAIL)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        {   /* only allow SF_STATIC to be already closed */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            if(!(f->flags&SF_STATIC) )
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                return NIL(Sfio_t*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            sflags = f->flags;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            oldf = NIL(Sfio_t*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        else
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        {   /* reopening an open stream, close it first */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            sflags = f->flags;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            if(((f->mode&SF_RDWR) != f->mode && _sfmode(f,0,0) < 0) ||
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin               SFCLOSE(f) < 0 )
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                return NIL(Sfio_t*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            if(f->data && ((flags&SF_STRING) || size != (size_t)SF_UNBOUND) )
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            {   if(sflags&SF_MALLOC)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                    free((Void_t*)f->data);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                f->data = NIL(uchar*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            if(!f->data)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                sflags &= ~SF_MALLOC;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    if(!f)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    {   /* reuse a standard stream structure if possible */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        if(!(flags&SF_STRING) && file >= 0 && file <= 2)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        {   f = file == 0 ? sfstdin : file == 1 ? sfstdout : sfstderr;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            if(f)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            {   if(f->mode&SF_AVAIL)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                {   sflags = f->flags;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                    SFCLEAR(f, f->mutex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                else    f = NIL(Sfio_t*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        if(!f)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        {   if(!(f = (Sfio_t*)malloc(sizeof(Sfio_t))) )
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin                return NIL(Sfio_t*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin            SFCLEAR(f, NIL(Vtmutex_t*));
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    /* create a mutex */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    if(!f->mutex)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        f->mutex = vtmtxopen(NIL(Vtmutex_t*), VT_INIT);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    /* stream type */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    f->mode = (flags&SF_READ) ? SF_READ : SF_WRITE;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    f->flags = (flags&SF_FLAGS) | (sflags&(SF_MALLOC|SF_STATIC));
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    f->bits = (flags&SF_RDWR) == SF_RDWR ? SF_BOTH : 0;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    f->file = file;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    f->here = f->extent = 0;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    f->getr = f->tiny[0] = 0;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    f->mode |= SF_INIT;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    if(size != (size_t)SF_UNBOUND)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    {   f->size = size;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        f->data = size <= 0 ? NIL(uchar*) : (uchar*)buf;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    f->endb = f->endr = f->endw = f->next = f->data;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    if(_Sfnotify)
7c2fbfb345896881c631598ee3852ce9ce33fb07April Chin        (*_Sfnotify)(f, SF_NEW, (void*)((long)f->file));
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    if(f->flags&SF_STRING)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin        (void)_sfmode(f,f->mode&SF_RDWR,0);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin    return f;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin}