是否有办法在bash上比较这些字符串,例如:2.4.5和2.8和2.4.5.1?
当前回答
哇……这是一个老问题,但我认为这是一个相当优雅的答案。首先,使用shell参数展开(参见shell参数展开)将每个点分隔的版本转换为自己的数组。
v1="05.2.3" # some evil examples that work here
v2="7.001.0.0"
declare -a v1_array=(${v1//./ })
declare -a v2_array=(${v2//./ })
现在,这两个数组将版本号按优先级顺序作为数值字符串。上面的许多解决方案都是从这里开始的,但它们都源于这样的观察:版本字符串只是一个具有任意基数的整数。我们可以测试找到第一个不相等的数字(就像strcmp对字符串中的字符所做的那样)。
compare_version() {
declare -a v1_array=(${1//./ })
declare -a v2_array=(${2//./ })
while [[ -nz $v1_array ]] || [[ -nz $v2_array ]]; do
let v1_val=${v1_array:-0} # this will remove any leading zeros
let v2_val=${v2_array:-0}
let result=$((v1_val-v2_val))
if (( result != 0 )); then
echo $result
return
fi
v1_array=("${v1_array[@]:1}") # trim off the first "digit". it doesn't help
v2_array=("${v2_array[@]:1}")
done
# if we get here, both the arrays are empty and neither has been numerically
# different, which is equivalent to the two versions being equal
echo 0
return
}
如果第一个版本小于第二个版本,则返回负数,如果相等则返回零,如果第一个版本大于第二个版本则返回正数。一些输出:
$ compare_version 1 1.2
-2
$ compare_version "05.1.3" "5.001.03.0.0.0.1"
-1
$ compare_version "05.1.3" "5.001.03.0.0.0"
0
$ compare_version "05.1.3" "5.001.03.0"
0
$ compare_version "05.1.3" "5.001.30.0"
-27
$ compare_version "05.2.3" "7.001.0.0"
-2
$ compare_version "05.1.3" "5.001.30.0"
-27
$ compare_version "7.001.0.0" "05.1.3"
2
堕落的例子,”。2”或“3.0.”不起作用(未定义的结果),并且如果'. 2 '旁边出现非数字字符。它可能会失败(还没有测试),但肯定是没有定义的。因此,这应该与一个消毒函数或适当的检查有效的格式相匹配。此外,我相信通过一些调整,可以在没有太多额外负担的情况下使其更加健壮。
其他回答
这里是另一个没有任何外部调用的纯bash解决方案:
#!/bin/bash
function version_compare {
IFS='.' read -ra ver1 <<< "$1"
IFS='.' read -ra ver2 <<< "$2"
[[ ${#ver1[@]} -gt ${#ver2[@]} ]] && till=${#ver1[@]} || till=${#ver2[@]}
for ((i=0; i<${till}; i++)); do
local num1; local num2;
[[ -z ${ver1[i]} ]] && num1=0 || num1=${ver1[i]}
[[ -z ${ver2[i]} ]] && num2=0 || num2=${ver2[i]}
if [[ $num1 -gt $num2 ]]; then
echo ">"; return 0
elif
[[ $num1 -lt $num2 ]]; then
echo "<"; return 0
fi
done
echo "="; return 0
}
echo "${1} $(version_compare "${1}" "${2}") ${2}"
还有更简单的解决方案,如果你确定所讨论的版本在第一个点后不包含前导零:
#!/bin/bash
function version_compare {
local ver1=${1//.}
local ver2=${2//.}
if [[ $ver1 -gt $ver2 ]]; then
echo ">"; return 0
elif
[[ $ver1 -lt $ver2 ]]; then
echo "<"; return 0
fi
echo "="; return 0
}
echo "${1} $(version_compare "${1}" "${2}") ${2}"
这适用于像1.2.3 vs 1.3.1 vs 0.9.7这样的版本,但不适用于其他版本 1.2.3 vs 1.2.3.0或1.01.1 vs 1.1.1
function version { echo "$@" | awk -F. '{ printf("%d%03d%03d%03d\n", $1,$2,$3,$4); }'; }
这样用:
if [ $(version $VAR) -ge $(version "6.2.0") ]; then
echo "Version is up to date"
fi
(来自https://apple.stackexchange.com/a/123408/11374)
下面是另一个纯bash版本,比公认的答案要小得多。它只检查版本是否小于或等于“最小版本”,并且它将按字典顺序检查字母数字序列,这通常会给出错误的结果(举个常见的例子,“snapshot”不晚于“release”)。它将工作的主要/次要。
is_number() {
case "$BASH_VERSION" in
3.1.*)
PATTERN='\^\[0-9\]+\$'
;;
*)
PATTERN='^[0-9]+$'
;;
esac
[[ "$1" =~ $PATTERN ]]
}
min_version() {
if [[ $# != 2 ]]
then
echo "Usage: min_version current minimum"
return
fi
A="${1%%.*}"
B="${2%%.*}"
if [[ "$A" != "$1" && "$B" != "$2" && "$A" == "$B" ]]
then
min_version "${1#*.}" "${2#*.}"
else
if is_number "$A" && is_number "$B"
then
[[ "$A" -ge "$B" ]]
else
[[ ! "$A" < "$B" ]]
fi
fi
}
当Bash变得太复杂时,就把它输送到python中!
vercomp(){ echo "$1" "$2" | python3 -c "import re, sys; arr = lambda x: list(map(int, re.split('[^0-9]+', x))); x, y = map(arr, sys.stdin.read().split()); exit(not x >= y)"; }
比较两个版本号的例子:
vercomp 2.8 2.4.5 && echo ">=" || echo "<"
这个python一行代码比较左边版本号和右边版本号,如果左边版本号等于或更高,则退出0。它还处理2.4.5rc3这样的版本
分解后,这是可读的代码:
import re, sys
# Convert a version string into a list "2.4.5" -> [2, 4, 5]
arr = lambda x: list(map(int, re.split('[^0-9]+', x)))
# Read the version numbers from stdin and apply the above function to them
x, y = map(arr, sys.stdin.read().split())
# Exit 0 if the left number is greater than the right
exit(not x >= y)
这里有一个支持修订的纯Bash解决方案(例如。“1.0-r1”),答案是基于丹尼斯·威廉姆森(Dennis Williamson)发布的答案。可以很容易地修改它以支持'-RC1'之类的东西,或者通过更改正则表达式从更复杂的字符串中提取版本。
有关实现的详细信息,请参考代码内注释和/或启用包含的调试代码:
#!/bin/bash
# Compare two version strings [$1: version string 1 (v1), $2: version string 2 (v2)]
# Return values:
# 0: v1 == v2
# 1: v1 > v2
# 2: v1 < v2
# Based on: https://stackoverflow.com/a/4025065 by Dennis Williamson
function compare_versions() {
# Trivial v1 == v2 test based on string comparison
[[ "$1" == "$2" ]] && return 0
# Local variables
local regex="^(.*)-r([0-9]*)$" va1=() vr1=0 va2=() vr2=0 len i IFS="."
# Split version strings into arrays, extract trailing revisions
if [[ "$1" =~ ${regex} ]]; then
va1=(${BASH_REMATCH[1]})
[[ -n "${BASH_REMATCH[2]}" ]] && vr1=${BASH_REMATCH[2]}
else
va1=($1)
fi
if [[ "$2" =~ ${regex} ]]; then
va2=(${BASH_REMATCH[1]})
[[ -n "${BASH_REMATCH[2]}" ]] && vr2=${BASH_REMATCH[2]}
else
va2=($2)
fi
# Bring va1 and va2 to same length by filling empty fields with zeros
(( ${#va1[@]} > ${#va2[@]} )) && len=${#va1[@]} || len=${#va2[@]}
for ((i=0; i < len; ++i)); do
[[ -z "${va1[i]}" ]] && va1[i]="0"
[[ -z "${va2[i]}" ]] && va2[i]="0"
done
# Append revisions, increment length
va1+=($vr1)
va2+=($vr2)
len=$((len+1))
# *** DEBUG ***
#echo "TEST: '${va1[@]} (?) ${va2[@]}'"
# Compare version elements, check if v1 > v2 or v1 < v2
for ((i=0; i < len; ++i)); do
if (( 10#${va1[i]} > 10#${va2[i]} )); then
return 1
elif (( 10#${va1[i]} < 10#${va2[i]} )); then
return 2
fi
done
# All elements are equal, thus v1 == v2
return 0
}
# ---------- everything below this line is just for testing ----------
# Test compare_versions [$1: version string 1, $2: version string 2, $3: expected result]
function test_compare_versions() {
local op
compare_versions "$1" "$2"
case $? in
0) op="==" ;;
1) op=">" ;;
2) op="<" ;;
esac
if [[ "$op" == "$3" ]]; then
echo -e "\e[1;32mPASS: '$1 $op $2'\e[0m"
else
echo -e "\e[1;31mFAIL: '$1 $3 $2' (result: '$1 $op $2')\e[0m"
fi
}
echo -e "\nThe following tests should pass:"
while read -r test; do
test_compare_versions $test
done << EOF
1 1 ==
2.1 2.2 <
3.0.4.10 3.0.4.2 >
4.08 4.08.01 <
3.2.1.9.8144 3.2 >
3.2 3.2.1.9.8144 <
1.2 2.1 <
2.1 1.2 >
5.6.7 5.6.7 ==
1.01.1 1.1.1 ==
1.1.1 1.01.1 ==
1 1.0 ==
1.0 1 ==
1.0.2.0 1.0.2 ==
1..0 1.0 ==
1.0 1..0 ==
1.0-r1 1.0-r3 <
1.0-r9 2.0 <
3.0-r15 3.0-r9 >
...-r1 ...-r2 <
2.0-r1 1.9.8.21-r2 >
1.0 3.8.9.32-r <
-r -r3 <
-r3 -r >
-r3 -r3 ==
-r -r ==
0.0-r2 0.0.0.0-r2 ==
1.0.0.0-r2 1.0-r2 ==
0.0.0.1-r7 -r9 >
0.0-r0 0 ==
1.002.0-r6 1.2.0-r7 <
001.001-r2 1.1-r2 ==
5.6.1-r0 5.6.1 ==
EOF
echo -e "\nThe following tests should fail:"
while read -r test; do
test_compare_versions $test
done << EOF
1 1 >
3.0.5-r5 3..5-r5 >
4.9.21-r3 4.8.22-r9 <
1.0-r 1.0-r1 ==
-r 1.0-r >
-r1 0.0-r1 <
-r2 0-r2 <
EOF