How to increment version number in a shell script?

Question

The following simple version control script is meant to find the last version number of a given file, increment it, run a given command with the newly created file (e.g., ed

Answer 1

Another option is to use Python. I think this way it a bit more readable than using plain Bash or Perl.

function increase_version() {
    python - "$1" <<EOF
import sys
version = sys.argv[1]
base, _, minor = version.rpartition('.')
print(base + '.' + str(int(minor) + 1))
EOF
}

Answer 2

Tired of bash? Why not try Perl?

$ cat versions
1.2.3.44
1.2.3.9
1.2.3
9

$ cat versions | perl -ne 'chomp; print join(".", splice(@{[split/\./,$_]}, 0, -1), map {++$_} pop @{[split/\./,$_]}), "\n";'
1.2.3.45
1.2.3.10
1.2.4
10

Not quite in compliance with the requirement, of course.

Answer 3

$ echo 1.2.3.4 | awk -F. -v OFS=. 'NF==1{print ++$NF}; NF>1{if(length($NF+1)>length($NF))$(NF-1)++; $NF=sprintf("%0*d", length($NF), ($NF+1)%(10^length($NF))); print}'
1.2.3.5

---

1.2.3.9  => 1.2.4.0
1.2.3.44 => 1.2.3.45
1.2.3.99 => 1.2.4.00
1.2.3.999=> 1.2.4.000
1.2.9    => 1.3.0
999      => 1000

UPDATE:

#!/usr/bin/gawk -f

BEGIN{
    v[1] = "1.2.3.4"
    v[2] = "1.2.3.44"
    v[3] = "1.2.3.99"
    v[4] = "1.2.3"
    v[5] = "9"
    v[6] = "9.9.9.9"
    v[7] = "99.99.99.99"
    v[8] = "99.0.99.99"
    v[9] = ""

    for(i in v)
        printf("#%d: %s => %s\n", i, v[i], inc(v[i])) | "sort | column -t"
}

function inc(s,    a, len1, len2, len3, head, tail)
{
    split(s, a, ".")

    len1 = length(a)
    if(len1==0)
        return -1
    else if(len1==1)
        return s+1

    len2 = length(a[len1])
    len3 = length(a[len1]+1)

    head = join(a, 1, len1-1)
    tail = sprintf("%0*d", len2, (a[len1]+1)%(10^len2))

    if(len2==len3)
        return head "." tail
    else
        return inc(head) "." tail
}

function join(a, x, y,    s)
{
    for(i=x; i<y; i++)
        s = s a[i] "."
    return s a[y]
}

---

$ chmod +x inc.awk
$ ./inc.awk
#1:  1.2.3.4      =>  1.2.3.5
#2:  1.2.3.44     =>  1.2.3.45
#3:  1.2.3.99     =>  1.2.4.00
#4:  1.2.3        =>  1.2.4
#5:  9            =>  10
#6:  9.9.9.9      =>  10.0.0.0
#7:  99.99.99.99  =>  100.00.00.00
#8:  99.0.99.99   =>  99.1.00.00
#9:  =>           -1

Answer 4

Here are a couple more flexible options. Both accept a second argument to indicate which position to increment.

1. Simple function

For more predictable input.

# Usage: increment_version <version> [<position>]
increment_version() {
 local v=$1
 if [ -z $2 ]; then 
    local rgx='^((?:[0-9]+\.)*)([0-9]+)($)'
 else 
    local rgx='^((?:[0-9]+\.){'$(($2-1))'})([0-9]+)(\.|$)'
    for (( p=`grep -o "\."<<<".$v"|wc -l`; p<$2; p++)); do 
       v+=.0; done; fi
 val=`echo -e "$v" | perl -pe 's/^.*'$rgx'.*$/$2/'`
 echo "$v" | perl -pe s/$rgx.*$'/${1}'`printf %0${#val}s $(($val+1))`/
}

# EXAMPLE   ------------->   # RESULT
increment_version 1          # 2
increment_version 1.0.0      # 1.0.1
increment_version 1 2        # 1.1
increment_version 1.1.1 2    # 1.2
increment_version 00.00.001  # 00.00.002

2. Robust function

For use with scripts, or more customizability to apply to various versioning systems. It could use a couple more options, but as it stands now it works for my projects using the "major.minor[.maintenance[.build]]" version sequences.

# Accepts a version string and prints it incremented by one.
# Usage: increment_version <version> [<position>] [<leftmost>]
increment_version() {
   local usage=" USAGE: $FUNCNAME [-l] [-t] <version> [<position>] [<leftmost>]
           -l : remove leading zeros
           -t : drop trailing zeros
    <version> : The version string.
   <position> : Optional. The position (starting with one) of the number 
                within <version> to increment.  If the position does not 
                exist, it will be created.  Defaults to last position.
   <leftmost> : The leftmost position that can be incremented.  If does not
                exist, position will be created.  This right-padding will
                occur even to right of <position>, unless passed the -t flag."

   # Get flags.
   local flag_remove_leading_zeros=0
   local flag_drop_trailing_zeros=0
   while [ "${1:0:1}" == "-" ]; do
      if [ "$1" == "--" ]; then shift; break
      elif [ "$1" == "-l" ]; then flag_remove_leading_zeros=1
      elif [ "$1" == "-t" ]; then flag_drop_trailing_zeros=1
      else echo -e "Invalid flag: ${1}\n$usage"; return 1; fi
      shift; done

   # Get arguments.
   if [ ${#@} -lt 1 ]; then echo "$usage"; return 1; fi
   local v="${1}"             # version string
   local targetPos=${2-last}  # target position
   local minPos=${3-${2-0}}   # minimum position

   # Split version string into array using its periods. 
   local IFSbak; IFSbak=IFS; IFS='.' # IFS restored at end of func to                     
   read -ra v <<< "$v"               #  avoid breaking other scripts.

   # Determine target position.
   if [ "${targetPos}" == "last" ]; then 
      if [ "${minPos}" == "last" ]; then minPos=0; fi
      targetPos=$((${#v[@]}>${minPos}?${#v[@]}:$minPos)); fi
   if [[ ! ${targetPos} -gt 0 ]]; then
      echo -e "Invalid position: '$targetPos'\n$usage"; return 1; fi
   (( targetPos--  )) || true # offset to match array index

   # Make sure minPosition exists.
   while [ ${#v[@]} -lt ${minPos} ]; do v+=("0"); done;

   # Increment target position.
   v[$targetPos]=`printf %0${#v[$targetPos]}d $((10#${v[$targetPos]}+1))`;

   # Remove leading zeros, if -l flag passed.
   if [ $flag_remove_leading_zeros == 1 ]; then
      for (( pos=0; $pos<${#v[@]}; pos++ )); do
         v[$pos]=$((${v[$pos]}*1)); done; fi

   # If targetPosition was not at end of array, reset following positions to
   #   zero (or remove them if -t flag was passed).
   if [[ ${flag_drop_trailing_zeros} -eq "1" ]]; then
        for (( p=$((${#v[@]}-1)); $p>$targetPos; p-- )); do unset v[$p]; done
   else for (( p=$((${#v[@]}-1)); $p>$targetPos; p-- )); do v[$p]=0; done; fi

   echo "${v[*]}"
   IFS=IFSbak
   return 0
}

# EXAMPLE   ------------->   # RESULT
increment_version 1          # 2
increment_version 1 2        # 1.1
increment_version 1 3        # 1.0.1
increment_version 1.0.0      # 1.0.1
increment_version 1.2.3.9    # 1.2.3.10
increment_version 00.00.001  # 00.00.002
increment_version -l 00.001  # 0.2
increment_version 1.1.1.1 2   # 1.2.0.0
increment_version -t 1.1.1 2  # 1.2
increment_version v1.1.3      # v1.1.4
increment_version 1.2.9 2 4     # 1.3.0.0
increment_version -t 1.2.9 2 4  # 1.3
increment_version 1.2.9 last 4  # 1.2.9.1

Obviously, this is excessive just to increment a version string. But I wrote this because I had a need for different types of projects, and because if speed is not an issue, I prefer reusability over tweaking the same code across dozens of scripts. I guess that's just my object-oriented side leaking into my scripts.

Answer 5

Using just bash, wc and sed:

#! /bin/bash
for v in 1.2.3.44 1.2.3.9 1.2.3 9 1.4.29.9 9.99.9 ; do
    echo -n $v '-> '

    num=${v//./}
    let num++

    re=${v//./)(}
    re=${re//[0-9]/.}')'
    re=${re#*)}

    count=${v//[0-9]/}
    count=$(wc -c<<<$count)
    out=''
    for ((i=count-1;i>0;i--)) ; do
        out='.\'$i$out
    done

    sed -r s/$re$/$out/ <<<$num
done