sfflsbuf.c revision 3f54fd611f536639ec30dd53c48e5ec1897cc7d9
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1985-2011 AT&T Intellectual Property *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* 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"
/* Write a buffer out to a file descriptor or
** extending a buffer for a SF_STRING stream.
**
** Written by Kiem-Phong Vo
*/
#if __STD_C
int _sfflsbuf(Sfio_t* f, int c)
#else
int _sfflsbuf(f,c)
Sfio_t* f; /* write out the buffered content of this stream */
int c; /* if c>=0, c is also written out */
#endif
{
ssize_t n, w, written;
uchar* data;
uchar outc;
int local, isall;
int inpc = c;
SFMTXDECL(f); /* declare a local stream variable for multithreading */
SFMTXENTER(f,-1);
GETLOCAL(f,local);
for(written = 0;; f->mode &= ~SF_LOCK)
{ /* check stream mode */
if(SFMODE(f,local) != SF_WRITE && _sfmode(f,SF_WRITE,local) < 0)
SFMTXRETURN(f, -1);
SFLOCK(f,local);
/* current data extent */
n = f->next - (data = f->data);
if(n == (f->endb-data) && (f->flags&SF_STRING))
{ /* call sfwr() to extend string buffer and process events */
w = ((f->bits&SF_PUTR) && f->val > 0) ? f->val : 1;
(void)SFWR(f, data, w, f->disc);
/* !(f->flags&SF_STRING) is required because exception
handlers may turn a string stream to a file stream */
if(f->next < f->endb || !(f->flags&SF_STRING) )
n = f->next - (data = f->data);
else
{ SFOPEN(f,local);
SFMTXRETURN(f, -1);
}
}
if(c >= 0)
{ /* write into buffer */
if(n < (f->endb - (data = f->data)))
{ *f->next++ = c;
if(c == '\n' &&
(f->flags&SF_LINE) && !(f->flags&SF_STRING))
{ c = -1;
n += 1;
}
else break;
}
else if(n == 0)
{ /* unbuffered io */
outc = (uchar)c;
data = &outc;
c = -1;
n = 1;
}
}
if(n == 0 || (f->flags&SF_STRING))
break;
isall = SFISALL(f,isall);
if((w = SFWR(f,data,n,f->disc)) > 0)
{ if((n -= w) > 0) /* save unwritten data, then resume */
memcpy((char*)f->data,(char*)data+w,n);
written += w;
f->next = f->data+n;
if(c < 0 && (!isall || n == 0))
break;
}
else if(w == 0)
{ if(written > 0) /* some buffer was cleared */
break; /* do normal exit below */
else /* nothing was done, returning failure */
{ SFOPEN(f,local);
SFMTXRETURN(f, -1);
}
}
else /* w < 0 means SF_EDISC or SF_ESTACK in sfwr() */
{ if(c < 0) /* back to the calling write operation */
break;
else continue; /* try again to write out c */
}
}
SFOPEN(f,local);
if(inpc < 0)
inpc = f->endb-f->next;
SFMTXRETURN(f,inpc);
}