xref: /illumos-gate/usr/src/test/zfs-tests/include/math.shlib (revision b666b5bebdde1067e2d0f2b91fd28a5243311a1a)
1#
2# This file and its contents are supplied under the terms of the
3# Common Development and Distribution License ("CDDL"), version 1.0.
4# You may only use this file in accordance with the terms of version
5# 1.0 of the CDDL.
6#
7# A full copy of the text of the CDDL should have accompanied this
8# source.  A copy of the CDDL is also available via the Internet at
9# http://www.illumos.org/license/CDDL.
10#
11
12#
13# Copyright (c) 2012, 2016 by Delphix. All rights reserved.
14#
15
16#
17# Return 0 if the percentage difference between $a and $b is $percent or
18# greater. Return 1 if the percentage is lower or if we would divide by
19# zero. For use like this:
20#
21# Do $action if the calculated percentage is greater or equal to that passed in:
22#	within_percent A B P && $action
23# Do $action if the calculated percentage is less than that passed in:
24#	within_percent A B P || $action
25#
26function within_percent
27{
28	typeset a=$1
29	typeset b=$1
30	typeset percent=$3
31
32	# Set $a or $b to $2 such that a >= b
33	[[ '1' = $(echo "if ($2 > $a) 1" | bc) ]] && a=$2 || b=$2
34
35	# Prevent division by 0
36	[[ $a =~ [1-9] ]] || return 1
37
38	typeset p=$(echo "scale=2; $b * 100 / $a" | bc)
39	log_note "Comparing $a and $b given $percent% (calculated: $p%)"
40	[[ '1' = $(echo "scale=2; if ($p >= $percent) 1" | bc) ]] && return 0
41
42	return 1
43}
44
45#
46# Return 0 if value is within +/-tolerance of target.
47# Return 1 if value exceeds our tolerance.
48# For use like this:
49#
50# Do $action if value is within the tolerance from target passed in:
51#	within_tolerance VAL TAR TOL && $action
52# Do $action if value surpasses the tolerance from target passed in:
53#	within_tolerance VAL TAR TOL || $action
54#
55function within_tolerance #value #target #tolerance
56{
57	typeset val=$1
58	typeset target=$2
59	typeset tol=$3
60
61	typeset diff=$((abs(val - target)))
62	log_note "Checking if $val is within +/-$tol of $target (diff: $diff)"
63	((diff <= tol)) && return 0
64
65	return 1
66}
67
68#
69# Return 0 if the human readable string of the form <value>[suffix] can
70# be converted to bytes.  Allow suffixes are shown in the table below.
71#
72function to_bytes
73{
74	typeset size=$1
75	typeset value=$(echo "$size" | grep -o '[0-9]\+')
76
77	case $size in
78		*PB|*pb|*P|*p)	factor='1024^5'	;;
79		*TB|*tb|*T|*t)	factor='1024^4'	;;
80		*GB|*gb|*G|*g)	factor='1024^3'	;;
81		*MB|*mb|*M|*m)	factor='1024^2'	;;
82		*KB|*kb|*K|*k)	factor='1024^1'	;;
83		*B|*b)		factor='1024^0'	;;
84		*[!0-9.]*)	return 1 ;;
85		*)		factor='1024^0'	;;
86	esac
87
88	echo "$value * ($factor)" | bc
89
90	return 0
91}
92
93#
94# Verify $a is equal to $b, otherwise raise an error specifying
95# the $type of values being compared
96#
97function verify_eq # <a> <b> <type>
98{
99	typeset a=$1
100	typeset b=$2
101	typeset type=$3
102
103	if [[ $a -ne $b ]]; then
104		log_fail "Compared $type should be equal: $a != $b"
105	fi
106}
107
108#
109# Verify $a is not equal to $b, otherwise raise an error specifying
110# the $type of values being compared
111#
112function verify_ne # <a> <b> <type>
113{
114	typeset a=$1
115	typeset b=$2
116	typeset type=$3
117
118	if [[ $a -eq $b ]]; then
119		log_fail "Compared $type should be not equal: $a == $b"
120	fi
121}
122