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/*
* Copyright (C) 1984-2012 Mark Nudelman
* Modified for use with illumos by Garrett D'Amore.
* Copyright 2014 Garrett D'Amore <garrett@damore.org>
*
* You may distribute under the terms of either the GNU General Public
* License or the Less License, as specified in the README file.
*
* For more information, see the README file.
*/
/*
* Operating system dependent routines.
*
* Most of the stuff in here is based on Unix, but an attempt
* has been made to make things work on other operating systems.
* This will sometimes result in a loss of functionality, unless
* someone rewrites code specifically for the new operating system.
*
* The makefile provides defines to decide whether various
* Unix features are present.
*/
#include <errno.h>
#include <signal.h>
#include <time.h>
#include "less.h"
/*
* Like read() system call, but is deliberately interruptible.
*/
int
iread(int fd, unsigned char *buf, unsigned int len)
{
int n;
start:
flush(0);
n = read(fd, buf, len);
if (n == -1) {
/*
* Certain values of errno indicate we should just retry the
* read.
*/
if (errno == EINTR)
return (READ_INTR);
if (errno == EAGAIN)
goto start;
return (-1);
}
return (n);
}
/*
* errno_message: Return an error message based on the value of "errno".
*/
char *
errno_message(char *filename)
{
return (easprintf("%s: %s", filename, strerror(errno)));
}
static off_t
muldiv(off_t val, off_t num, off_t den)
{
double v = (((double)val) * num) / den;
return ((off_t)(v + 0.5));
}
/*
* Return the ratio of two off_t, as a percentage.
* {{ Assumes a off_t is a long int. }}
*/
int
percentage(off_t num, off_t den)
{
return ((int)muldiv(num, (off_t)100, den));
}
/*
* Return the specified percentage of a off_t.
*/
off_t
percent_pos(off_t pos, int percent, long fraction)
{
/*
* Change percent (parts per 100) to perden
* (parts per NUM_FRAC_DENOM).
*/
off_t perden = (percent * (NUM_FRAC_DENOM / 100)) + (fraction / 100);
if (perden == 0)
return (0);
return (muldiv(pos, perden, (off_t)NUM_FRAC_DENOM));
}
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