Linux bash logger:找不到将MaxBackupIndex添加到此记录器实现的方法

我一直试图修改这个日志，但我无法使它工作。以下是一个示例：

#!/bin/bash

TRUE=1
FALSE=0

############### Added for testing
logger_LOG_ENABLED=$TRUE

logger_rootLogger=$TRACE,f,s
logger_appender_f=file
logger_appender_f_dir=$(pwd)
logger_appender_f_file=test.log
logger_appender_f_roll_format=%Y%m
logger_appender_f_roll=$TRUE
logger_appender_f_maxBackupIndex=10

####################################

logger_abs(){
    if [ "${1:0:1}" == "." ]; then
        builtin echo ${rootDir}/${1}
    else
        builtin echo ${1}
    fi
}

logger_check_app_dir(){

    if [ "$logger_LOG_ENABLED" -eq $TRUE ]; then
        dir=$(logger_abs $1)
        if [ ! -d ${dir} ]; then
            #log a seperation line
            mkdir $dir
        fi
    fi
}

# Delete old log files
# $1 Log directory
# $2 Log filename
# $3 Log filename suffix
# $4 Max backup index
logger_delete_old_files(){
    ##### Added for testing
    builtin echo "Running logger_delete_old_files $@" >&2
    #####
    if [ "$logger_LOG_ENABLED" -eq $TRUE ] && [ -n "$3" ] && [ "$4" -gt 0 ]; then
        local directory=$(logger_abs $1)
        local filename=$2
        local maxBackupIndex=$4
        local suffix=$(echo "${3}" | sed -re 's/[^.]/?/g')
        local logFileList=$(find "${directory}" -mindepth 1 -maxdepth 1 -name "${filename}${suffix}" -type f | xargs ls -1rt)
        local fileCnt=$(builtin echo -e "${logFileList}" | wc -l)
        local fileToDeleteCnt=$(($fileCnt-$maxBackupIndex))
        local fileToDelete=($(builtin echo -e "${logFileList}" | head -n "${fileToDeleteCnt}" | sed ':a;N;$!ba;s/\n/ /g'))

        ##### Added for testing
        builtin echo "logger_delete_old_files About to start deletion ${fileToDelete[@]}" >&2
        #####

        if [ ${fileToDeleteCnt} -gt 0 ]; then
            for f in "${fileToDelete[@]}"; do
                #### Added for testing
                builtin echo "Removing file ${f}" >&2
                ####
                builtin eval rm -f ${f}
            done
        fi
    fi
}

#Appender
# $1 Log directory
# $2 Log file
# $3 Log file roll ?
# $4 Appender Name
logger_filename(){
    builtin echo "Running logger_filename $@" >&2
    local format
    local filename

    logger_check_app_dir "${1}"

    if [ ${3} -eq 1 ];then
        local formatProp=${4}_roll_format
        format=${!formatProp}
        if [ -z ${format} ]; then
            format=$logger_appender_file_format
        fi
        local suffix=.`date "+${format}"`

        filename=${1}/${2}${suffix}

        # Old log files deletion
        local previousFilenameVar=int_${4}_file_previous
        local maxBackupIndexVar=${4}_maxBackupIndex

        if [ -n "${!maxBackupIndexVar}" ] && [ "${!previousFilenameVar}" != "${filename}" ]; then
            builtin echo "logger_filename Stepped into if: $previousFilenameVar => ${!previousFilenameVar}" >&2
            builtin eval export $previousFilenameVar=$filename
            logger_delete_old_files "${1}" "${2}" "${suffix}" "${!maxBackupIndexVar}"
        fi
    else
        filename=${1}/${2}
    fi

    builtin echo $filename
}

######################## Added for testing
filename_caller(){
    builtin echo "filename_caller Call $1"
    output=$(logger_abs $(logger_filename "${logger_appender_f_dir}" "${logger_appender_f_file}" "1" "logger_appender_f" ))

    builtin echo ${output}
}

#### Previous logs generation
for i in {1101..1120}; do
    file="${logger_appender_f_file}.2012${i:2:3}"
    builtin echo "${file} $i"
    touch -m -t "2012${i}0000" ${logger_appender_f_dir}/$file
done

for i in {1..4}; do
    filename_caller $i
done

这是输出

test.log.201201 1101
test.log.201202 1102
test.log.201203 1103
test.log.201204 1104
test.log.201205 1105
test.log.201206 1106
test.log.201207 1107
test.log.201208 1108
test.log.201209 1109
test.log.201210 1110
test.log.201211 1111
test.log.201212 1112
test.log.201213 1113
test.log.201214 1114
test.log.201215 1115
test.log.201216 1116
test.log.201217 1117
test.log.201218 1118
test.log.201219 1119
test.log.201220 1120
filename_caller Call 1
/web/com/138245668210919/test.log.201310
filename_caller Call 2
/web/com/138245668210919/test.log.201310
filename_caller Call 3
/web/com/138245668210919/test.log.201310
filename_caller Call 4
/web/com/138245668210919/test.log.201310
Running logger_filename /web/com/138245668210919 test.log 1 logger_appender_f
logger_filename Stepped into if: int_logger_appender_f_file_previous => 
Running logger_delete_old_files /web/com/138245668210919 test.log .201310 10
logger_delete_old_files About to start deletion /web/com/138245668210919/test.log.201201 /web/com/138245668210919/test.log.201202 /web/com/138245668210919/test.log.201203 /web/com/138245668210919/test.log.201204 /web/com/138245668210919/test.log.201205 /web/com/138245668210919/test.log.201206 /web/com/138245668210919/test.log.201207 /web/com/138245668210919/test.log.201208 /web/com/138245668210919/test.log.201209 /web/com/138245668210919/test.log.201210
Removing file /web/com/138245668210919/test.log.201201
Removing file /web/com/138245668210919/test.log.201202
Removing file /web/com/138245668210919/test.log.201203
Removing file /web/com/138245668210919/test.log.201204
Removing file /web/com/138245668210919/test.log.201205
Removing file /web/com/138245668210919/test.log.201206
Removing file /web/com/138245668210919/test.log.201207
Removing file /web/com/138245668210919/test.log.201208
Removing file /web/com/138245668210919/test.log.201209
Removing file /web/com/138245668210919/test.log.201210
Running logger_filename /web/com/138245668210919 test.log 1 logger_appender_f
logger_filename Stepped into if: int_logger_appender_f_file_previous => 
Running logger_delete_old_files /web/com/138245668210919 test.log .201310 10
logger_delete_old_files About to start deletion 
Running logger_filename /web/com/138245668210919 test.log 1 logger_appender_f
logger_filename Stepped into if: int_logger_appender_f_file_previous => 
Running logger_delete_old_files /web/com/138245668210919 test.log .201310 10
logger_delete_old_files About to start deletion 
Running logger_filename /web/com/138245668210919 test.log 1 logger_appender_f
logger_filename Stepped into if: int_logger_appender_f_file_previous => 
Running logger_delete_old_files /web/com/138245668210919 test.log .201310 10
logger_delete_old_files About to start deletion 

仅当计算的日志文件名与前一个不同时，我希望logger_filename函数进入以下

if

：

if [ -n "${!maxBackupIndexVar}" ] && [ "${!previousFilenameVar}" != "${filename}" ]; then

要应用此场景，我需要正确设置${！previousFilenameVar}，但事实并非如此，因此logger_filename会一直使用此

if

，这实际上是不必要的

问题似乎是由于以下线路工作不正常造成的：

builtin eval export $previousFilenameVar=$filename

我有一些理论来解释原因：

• 在原始代码中，函数被声明并导出为只读，这使得它们无法修改全局变量。我删除了上面示例中的只读声明，但问题仍然存在
• 函数调用是在$（）中执行的，这将使它们运行到单独的shell实例中，这样修改的变量就不会导出到主shell中

但我无法找到解决这个问题的方法

---

感谢您的帮助，提前谢谢

我只是决定更改调用

logger\u filename

函数的方式：

#Appender
# $1 Log directory
# $2 Log file
# $3 Log file roll ?
# $4 Appender Name
# $5 Output filename variable
logger_filename(){
#return result
        local format
        local filename

        logger_check_app_dir "${1}"

        if [ ${3} -eq 1 ];then
                local formatProp=${4}_roll_format
                format=${!formatProp}
                if [ -z ${format} ]; then
                        format=$logger_appender_file_format
                fi
                local suffix=.`date "+${format}"`

                filename=${1}/${2}${suffix}

                # Old log files deletion
                local previousFilenameVar=${4}_file_previous
                local maxBackupIndexVar=${4}_maxBackupIndex

                if [ -n "${!maxBackupIndexVar}" ] && [ "${!previousFilenameVar}" != "${filename}" ]; then
                        eval $previousFilenameVar=$filename
                        logger_delete_old_files "${1}" "${2}" "${suffix}" "${!maxBackupIndexVar}"
                fi
        else
                filename=${1}/${2}
        fi

        #builtin echo $filename
        eval $5=$filename
}

local logFileName=
logger_filename "${logFileDir}" "${logFile}" "${logFileRoll}" "${3}" logFileName
builtin echo "$2" >>"$(logger_abs "${logFileName}")"

---

这样，函数不会在子shell中执行，变量

${！previousFilenameVar}

保留在作用域中。

您更改了什么？不要让我们把你的代码和上游代码区别开来。告诉我们输入是什么，预期和实际输出是什么，然后发布一段自包含的代码片段来演示问题。我制作了一个示例并添加了更多细节，以便问题更加明显。你的第二个理论是正确的

log4bash_filename

是在一个新进程中执行的，因此对

previousFilenameVar

的更改是该进程的本地更改。因此，基本上没有可应用的解决方法？除非写入临时文件并从中读取，否则不会。