/*
* Copyright (c) 2000-2001 Sendmail, Inc. and its suppliers.
* All rights reserved.
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Chris Torek.
*
* By using this file, you agree to the terms and conditions set
* forth in the LICENSE file which can be found at the top level of
* the sendmail distribution.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sm/gen.h>
SM_RCSID("@(#)$Id: fget.c,v 1.22 2001/08/27 18:54:14 gshapiro Exp $")
#include <stdlib.h>
#include <string.h>
#include <sm/io.h>
#include <sm/assert.h>
#include "local.h"
/*
** SM_IO_FGETS -- get a string from a file
**
** Read at most n-1 characters from the given file.
** Stop when a newline has been read, or the count ('n') runs out.
**
** Parameters:
** fp -- the file to read from
** timeout -- time to complete reading the string in milliseconds
** buf -- buffer to place read string in
** n -- size of 'buf'
**
** Returns:
** success: returns value of 'buf'
** failure: NULL (no characters were read)
** timeout: NULL and errno set to EAGAIN
**
** Side Effects:
** may move the file pointer
*/
char *
sm_io_fgets(fp, timeout, buf, n)
register SM_FILE_T *fp;
int timeout;
char *buf;
register int n;
{
register int len;
register char *s;
register unsigned char *p, *t;
SM_REQUIRE_ISA(fp, SmFileMagic);
if (n <= 0) /* sanity check */
return NULL;
s = buf;
n--; /* leave space for NUL */
while (n > 0)
{
/* If the buffer is empty, refill it. */
if ((len = fp->f_r) <= 0)
{
/*
** Timeout is only passed if we can't get the data
** from the buffer (which is counted as immediately).
*/
if (sm_refill(fp, timeout) != 0)
{
/* EOF/error: stop with partial or no line */
if (s == buf)
return NULL;
break;
}
len = fp->f_r;
}
p = fp->f_p;
/*
** Scan through at most n bytes of the current buffer,
** looking for '\n'. If found, copy up to and including
** newline, and stop. Otherwise, copy entire chunk
** and loop.
*/
if (len > n)
len = n;
t = (unsigned char *) memchr((void *) p, '\n', len);
if (t != NULL)
{
len = ++t - p;
fp->f_r -= len;
fp->f_p = t;
(void) memcpy((void *) s, (void *) p, len);
s[len] = 0;
return buf;
}
fp->f_r -= len;
fp->f_p += len;
(void) memcpy((void *) s, (void *) p, len);
s += len;
n -= len;
}
*s = 0;
return buf;
}