#!/bin/bash
#
# **lib/meta-config** - Configuration file manipulation functions
#
# Support for DevStack's local.conf meta-config sections
#
# These functions have no external dependencies and the following side-effects:
#
# CONFIG_AWK_CMD is defined, default is ``awk``
# Meta-config files contain multiple INI-style configuration files
# using a specific new section header to delimit them:
#
# [[group-name|file-name]]
#
# group-name refers to the group of configuration file changes to be processed
# at a particular time. These are called phases in ``stack.sh`` but
# group here as these functions are not DevStack-specific.
#
# file-name is the destination of the config file
# Save trace setting
_XTRACE_INC_META=$(set +o | grep xtrace)
set +o xtrace
# Allow the awk command to be overridden on legacy platforms
CONFIG_AWK_CMD=${CONFIG_AWK_CMD:-awk}
# Get the section for the specific group and config file
# get_meta_section infile group configfile
function get_meta_section {
local file=$1
local matchgroup=$2
local configfile=$3
[[ -r $file ]] || return 0
[[ -z $configfile ]] && return 0
$CONFIG_AWK_CMD -v matchgroup=$matchgroup -v configfile=$configfile '
BEGIN { group = "" }
/^\[\[.+\|.*\]\]/ {
gsub("[][]", "", $1);
split($1, a, "|");
if (a[1] == matchgroup && a[2] == configfile) {
group=a[1]
} else {
group=""
}
next
}
{
if (group != "")
print $0
}
' $file
}
# Get a list of config files for a specific group
# get_meta_section_files infile group
function get_meta_section_files {
local file=$1
local matchgroup=$2
[[ -r $file ]] || return 0
$CONFIG_AWK_CMD -v matchgroup=$matchgroup '
/^\[\[.+\|.*\]\]/ {
gsub("[][]", "", $1);
split($1, a, "|");
if (a[1] == matchgroup)
print a[2]
}
' $file
}
# Merge the contents of a meta-config file into its destination config file
# If configfile does not exist it will be created.
# merge_config_file infile group configfile
function merge_config_file {
local file=$1
local matchgroup=$2
local configfile=$3
# note, configfile might be a variable (note the iniset, etc
# created in the mega-awk below is "eval"ed too, so we just leave
# it alone.
local real_configfile
real_configfile=$(eval echo $configfile)
if [ ! -f $real_configfile ]; then
touch $real_configfile || die $LINENO "could not create config file $real_configfile ($configfile)"
fi
get_meta_section $file $matchgroup $configfile | \
$CONFIG_AWK_CMD -v configfile=$configfile '
BEGIN {
section = ""
last_section = ""
section_count = 0
}
/^\[.+\]/ {
gsub("[][]", "", $1);
section=$1
next
}
/^ *\#/ {
next
}
/^[^ \t]+/ {
# get offset of first '=' in $0
eq_idx = index($0, "=")
# extract attr & value from $0
attr = substr($0, 1, eq_idx - 1)
value = substr($0, eq_idx + 1)
# only need to strip trailing whitespace from attr
sub(/[ \t]*$/, "", attr)
# need to strip leading & trailing whitespace from value
sub(/^[ \t]*/, "", value)
sub(/[ \t]*$/, "", value)
# cfg_attr_count: number of config lines per [section, attr]
# cfg_attr: three dimensional array to keep all the config lines per [section, attr]
# cfg_section: keep the section names in the same order as they appear in local.conf
# cfg_sec_attr_name: keep the attr names in the same order as they appear in local.conf
if (! (section, attr) in cfg_attr_count) {
if (section != last_section) {
cfg_section[section_count++] = section
last_section = section
}
attr_count = cfg_sec_attr_count[section_count - 1]++
cfg_sec_attr_name[section_count - 1, attr_count] = attr
cfg_attr[section, attr, 0] = value
cfg_attr_count[section, attr] = 1
} else {
lno = cfg_attr_count[section, attr]++
cfg_attr[section, attr, lno] = value
}
}
END {
# Process each section in order
for (sno = 0; sno < section_count; sno++) {
section = cfg_section[sno]
# The ini routines simply append a config item immediately
# after the section header. To keep the same order as defined
# in local.conf, invoke the ini routines in the reverse order
for (attr_no = cfg_sec_attr_count[sno] - 1; attr_no >=0; attr_no--) {
attr = cfg_sec_attr_name[sno, attr_no]
if (cfg_attr_count[section, attr] == 1)
print "iniset " configfile " " section " " attr " \"" cfg_attr[section, attr, 0] "\""
else {
# For multiline, invoke the ini routines in the reverse order
count = cfg_attr_count[section, attr]
print "inidelete " configfile " " section " " attr
print "iniset " configfile " " section " " attr " \"" cfg_attr[section, attr, count - 1] "\""
for (l = count -2; l >= 0; l--)
print "iniadd_literal " configfile " " section " " attr " \"" cfg_attr[section, attr, l] "\""
}
}
}
}
' | while read a; do eval "$a"; done
}
# Merge all of the files specified by group
# merge_config_group infile group [group ...]
function merge_config_group {
local localfile=$1; shift
local matchgroups=$@
[[ -r $localfile ]] || return 0
local configfile group
for group in $matchgroups; do
for configfile in $(get_meta_section_files $localfile $group); do
local realconfigfile
local dir
realconfigfile=$(eval "echo $configfile")
if [[ -z $realconfigfile ]]; then
warn $LINENO "unknown config file specification: $configfile is undefined"
break
fi
dir=$(dirname $realconfigfile)
if [[ -d $dir ]]; then
merge_config_file $localfile $group $configfile
else
die $LINENO "bogus config file specification $configfile ($configfile=$realconfigfile, $dir is not a directory)"
fi
done
done
}
function extract_localrc_section {
local configfile=$1 # top_dir/local.conf
local localrcfile=$2 # top_dir/localrc
local localautofile=$3 # top_dir/.localrc.auto
if [[ -r $configfile ]]; then
LRC=$(get_meta_section_files $configfile local)
for lfile in $LRC; do
if [[ "$lfile" == "localrc" ]]; then
if [[ -r $localrcfile ]]; then
echo "localrc and local.conf:[[local]] both exist, using localrc"
else
echo "# Generated file, do not edit" >$localautofile
get_meta_section $configfile local $lfile >>$localautofile
fi
fi
done
fi
}
# Restore xtrace
$_XTRACE_INC_META
# Local variables:
# mode: shell-script
# End: