BUG: config_load之后，調(diào)用uci delete或者uci set xxx.xxx.xxx=''，再度掉用config_load，之后通過config_get讀取出來的值將會(huì)出錯(cuò),delete之后不使用commit
解決方法1：使用API函數(shù)config_unset或者config_set
解決方法2：
config_clear() {
local SECTION="$1"
#遍歷每一項(xiàng)option,并將其unset
for oldvar in `set | grep ^CONFIG_${SECTION:+${SECTION}_} | \
sed -e 's/\(.*\)=.*$/\1/'` ; do
unset $oldvar
done
}
config () {
local cfgtype="$1"
local name="$2"
config_clear $name
export ${NO_EXPORT:+-n} CONFIG_NUM_SECTIONS=$(($CONFIG_NUM_SECTIONS + 1))
name="${name:-cfg$CONFIG_NUM_SECTIONS}"
append CONFIG_SECTIONS "$name"
[ -n "$NO_CALLBACK" ] || config_cb "$cfgtype" "$name"
export ${NO_EXPORT:+-n} CONFIG_SECTION="$name"
export ${NO_EXPORT:+-n} "CONFIG_${CONFIG_SECTION}_TYPE=$cfgtype"
}
在調(diào)用api時(shí)，首先我們需要調(diào)用config_load
config_load() {
[ -n "$IPKG_INSTROOT" ] && return 0
uci_load "$@"
}
uci_load() {
local PACKAGE="$1"
local DATA
local RET
local VAR
_C=0
if [ -z "$CONFIG_APPEND" ]; then
for VAR in $CONFIG_LIST_STATE; do
export ${NO_EXPORT:+-n} CONFIG_${VAR}=
export ${NO_EXPORT:+-n} CONFIG_${VAR}_LENGTH=
done
export ${NO_EXPORT:+-n} CONFIG_LIST_STATE=
export ${NO_EXPORT:+-n} CONFIG_SECTIONS=
export ${NO_EXPORT:+-n} CONFIG_NUM_SECTIONS=0
export ${NO_EXPORT:+-n} CONFIG_SECTION=
fi
DATA="$(/sbin/uci ${UCI_CONFIG_DIR:+-c $UCI_CONFIG_DIR} ${LOAD_STATE:+-P /var/state} -S -n export "$PACKAGE" 2>/dev/null)"
RET="$?"
[ "$RET" != 0 -o -z "$DATA" ] || eval "$DATA"
unset DATA
${CONFIG_SECTION:+config_cb}
return "$RET"
}
1、首先通過uci export $PACKAGE 獲取配置文件的內(nèi)容（其他參數(shù)就不一一簡(jiǎn)紹了，具體查看uci --help）
package xxx
config xxx xxx
option xxx xxx
list????? xxx? xxx
2、之后eval "$DATA"，將package config option替換成函數(shù)（這一步是很讓我很驚艷的用法，得向大牛學(xué)習(xí)）
package() {
return 0
}
config () {
local cfgtype="$1"
local name="$2"
export ${NO_EXPORT:+-n} CONFIG_NUM_SECTIONS=$(($CONFIG_NUM_SECTIONS + 1))
name="${name:-cfg$CONFIG_NUM_SECTIONS}"
append CONFIG_SECTIONS "$name"
[ -n "$NO_CALLBACK" ] || config_cb "$cfgtype" "$name"
export ${NO_EXPORT:+-n} CONFIG_SECTION="$name"
export ${NO_EXPORT:+-n} "CONFIG_${CONFIG_SECTION}_TYPE=$cfgtype"
}
option () {
local varname="$1"; shift
local value="$*"
export ${NO_EXPORT:+-n} "CONFIG_${CONFIG_SECTION}_${varname}=$value"
[ -n "$NO_CALLBACK" ] || option_cb "$varname" "$*"
}
list() {
local varname="$1"; shift
local value="$*"
local len
config_get len "$CONFIG_SECTION" "${varname}_LENGTH" 0
[ $len = 0 ] && append CONFIG_LIST_STATE "${CONFIG_SECTION}_${varname}"
len=$(($len + 1))
config_set "$CONFIG_SECTION" "${varname}_ITEM$len" "$value"
config_set "$CONFIG_SECTION" "${varname}_LENGTH" "$len"
append "CONFIG_${CONFIG_SECTION}_${varname}" "$value" "$LIST_SEP"
list_cb "$varname" "$*"
}
3、通過這四個(gè)函數(shù)將每一項(xiàng)配置項(xiàng)設(shè)置到環(huán)境變量當(dāng)中
（bug出現(xiàn)原因：當(dāng)設(shè)入環(huán)境變量后，通過uci delete或uci set 刪除只會(huì)操作換存，在調(diào)用config_load 因?yàn)閛ption項(xiàng)不存在了，則不會(huì)在度設(shè)置到環(huán)境變量中，因此還是刪除之前的值，而不是空）
4、之后的config_get之類的函數(shù)就是獲取環(huán)境變量的值
for oldvar in `set | grep ^CONFIG_${SECTION:+${SECTION}_} | \
sed -e 's/\(.*\)=.*$/\1/'` ; do
for oldvar in `set | grep ^CONFIG_${SECTION:+${SECTION}_} | \
sed -e 's/\(.*\)=.*$/\1/'` ; do
for oldvar in `set | grep ^CONFIG_${SECTION:+${SECTION}_} | \
sed -e 's/\(.*\)=.*$/\1/'` ; do
for oldvar in `set | grep ^CONFIG_${SECTION:+${SECTION}_} | \
sed -e 's/\(.*\)=.*$/\1/'` ; do
for oldvar in `set | grep ^CONFIG_${SECTION:+${SECTION}_} | \
sed -e 's/\(.*\)=.*$/\1/'` ; do
for oldvar in `set | grep ^CONFIG_${SECTION:+${SECTION}_} | \
sed -e 's/\(.*\)=.*$/\1/'` ; do
