bash ini parser

In some situations i like to use INI files as configuration files, as python do. But bash do not provide a parser for these files, obviously you can use a awk code or a couple of sed calls, but if you are bash-priest and do not want to use nothing more, then you can try the following obscure code:

Update:Added support spaces between keys and values, described in comment #364

Update:Added a writer function, described in comment #370 with examples.

Update:Fix bug when values or keys contains a ‘#’ sign, as described in comment #397. Now only comments at the beginning of line are allowed.

Update:Fix bug in section evaluation when a file which match section expression exists in cwd, as described in comment #436. Fixed also a bug related with
parser when brackets are escaped (read #437.

cfg_parser ()
{
	ini="$(<$1)"                # read the file
	ini="${ini//[/\[}"          # escape [
	ini="${ini//]/\]}"          # escape ]
	IFS=$'\n' && ini=( ${ini} ) # convert to line-array
	ini=( ${ini[*]//;*/} )      # remove comments with ;
	ini=( ${ini[*]/\	=/=} )  # remove tabs before =
	ini=( ${ini[*]/=\	/=} )   # remove tabs be =
	ini=( ${ini[*]/\ =\ /=} )   # remove anything with a space around =
	ini=( ${ini[*]/#\\[/\}$'\n'cfg.section.} ) # set section prefix
	ini=( ${ini[*]/%\\]/ \(} )    # convert text2function (1)
	ini=( ${ini[*]/=/=\( } )    # convert item to array
	ini=( ${ini[*]/%/ \)} )     # close array parenthesis
	ini=( ${ini[*]/%\\ \)/ \\} ) # the multiline trick
	ini=( ${ini[*]/%\( \)/\(\) \{} ) # convert text2function (2)
	ini=( ${ini[*]/%\} \)/\}} ) # remove extra parenthesis
	ini[0]="" # remove first element
	ini[${#ini[*]} + 1]='}'    # add the last brace
	eval "$(echo "${ini[*]}")" # eval the result
}

cfg_writer ()
{
    IFS=' '$'\n'
    fun="$(declare -F)"
    fun="${fun//declare -f/}"
    for f in $fun; do
        [ "${f#cfg.section}" == "${f}" ] && continue
        item="$(declare -f ${f})"
        item="${item##*\{}"
        item="${item%\}}"
        item="${item//=*;/}"
        vars="${item//=*/}"
        eval $f
        echo "[${f#cfg.section.}]"
        for var in $vars; do
            echo $var=\"${!var}\"
        done
    done
}

And then you can parse your ini files as following:

# parse the config file called 'myfile.ini', with the following
# contents::
#   [sec2]
#   var2='something'
cfg.parser 'myfile.ini'

# enable section called 'sec2' (in the file [sec2]) for reading
cfg.section.sec2

# read the content of the variable called 'var2' (in the file
# var2=XXX). If your var2 is an array, then you can use
# ${var[index]}
echo "$var2"

Unfortunately, the cfg.parser() function do no support embedded spaces
in section names… yet