1.\" 2.\" Copyright (c) 2018 Netflix, Inc. 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions, and the following disclaimer, 10.\" without modification, immediately at the beginning of the file. 11.\" 2. The name of the author may not be used to endorse or promote products 12.\" derived from this software without specific prior written permission. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 18.\" ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.Dd July 8, 2018 27.Dt Q_QADDI 3 28.Os 29.Sh NAME 30.Nm Q_QADDI , 31.Nm Q_QDIVI , 32.Nm Q_QMULI , 33.Nm Q_QSUBI , 34.Nm Q_QFRACI , 35.Nm Q_QCPYVALI 36.Nd fixed-point math functions which apply integers to a Q number 37.Sh SYNOPSIS 38.In sys/qmath.h 39.Ft int 40.Fn Q_QADDI "QTYPE *a" "ITYPE b" 41.Ft int 42.Fn Q_QDIVI "QTYPE *a" "ITYPE b" 43.Ft int 44.Fn Q_QMULI "QTYPE *a" "ITYPE b" 45.Ft int 46.Fn Q_QSUBI "QTYPE *a" "ITYPE b" 47.Ft int 48.Fn Q_QFRACI "QTYPE *q" "ITYPE n" "ITYPE d" 49.Ft int 50.Fn Q_QCPYVALI "QTYPE *q" "ITYPE i" 51.Sh DESCRIPTION 52The 53.Fn Q_QADDI , 54.Fn Q_QDIVI , 55.Fn Q_QMULI 56and 57.Fn Q_QSUBI 58functions add, divide, multiply or subtract 59.Fa b 60to/by/from 61.Fa a 62respectively, storing the result in 63.Fa a . 64.Pp 65The 66.Fn Q_QFRACI 67function computes the fraction 68.Fa n 69divided by 70.Fa d 71and stores the fixed-point result in 72.Fa q . 73.Pp 74The 75.Fn Q_QCPYVALI 76function overwrites 77.Fa q Ap s 78integer and fractional bits with the Q representation of integer value 79.Fa i . 80.Pp 81All of those functions operate on 82the following data types: 83.Vt s8q_t , 84.Vt u8q_t , 85.Vt s16q_t , 86.Vt u16q_t , 87.Vt s32q_t , 88.Vt u32q_t , 89.Vt s64q_t , 90and 91.Vt u64q_t , 92which are referred to generically as 93.Fa QTYPE . 94The 95.Fa ITYPE 96refers to the 97.Xr stdint 7 98integer types. 99.Pp 100For more details, see 101.Xr qmath 3 . 102.Sh RETURN VALUES 103.Fn Q_QADDI , 104.Fn Q_QDIVI , 105.Fn Q_QMULI , 106.Fn Q_QSUBI , 107.Fn Q_QFRACI 108and 109.Fn Q_QCPYVALI 110functions return 0 on success, or an errno on failure. 111.Er EINVAL 112is returned for divide-by-zero. 113.Er EOVERFLOW 114and 115.Er ERANGE 116are returned for overflow and underflow respectively. 117.Sh SEE ALSO 118.Xr errno 2 , 119.Xr qmath 3 , 120.Xr stdint 7 121.Sh HISTORY 122The 123.Xr qmath 3 124functions first appeared in 125.Fx 13.0 . 126.Sh AUTHORS 127.An -nosplit 128The 129.Xr qmath 3 130functions and this manual page were written by 131.An Lawrence Stewart Aq Mt lstewart@FreeBSD.org 132and sponsored by Netflix, Inc. 133