试图让通用 sed 多行模式匹配和替换脚本工作

Question

在linuxtopia here的第 4.23.3 节中，有一种通用方法可以解决此海报所呈现的问题。 它似乎提供了一种方法来处理匹配目标的任何复杂内容模式，然后再次将其替换为任何其他复杂内容模式。 该技术被称为“滑动窗口”技术。

我相信下面的脚本忠实地再现了所描述的场景，并尝试结合 sed 脚本来证明该方法是可行的。

#!/bin/bash

DBG=1

###
### Code segment to be replaced
###
file1="File1.cpp"
rm -f "${file1}"
cat >"${file1}" <<"EnDoFiNpUt"
void Component::initialize()
{
    my_component = new ComponentClass();
}
EnDoFiNpUt

test ${DBG} -eq 1 && echo "fence 1"

###
### Code segment to be used as replacement
###
file2="File2.cpp"
rm -f "${file2}"
cat >"${file2}" <<"EnDoFiNpUt"
void Component::initialize()
{
    if (doInit)
    {
        my_component = new ComponentClass();
    }
    else
    {
        my_component.ptr = null;
    }
}
EnDoFiNpUt

test ${DBG} -eq 1 && echo "fence 2"

###
### Create demo input file
###
testfile="Test_INPUT.cpp"
rm -f "${testfile}"
{
    echo "
other code1()
{
    doing other things
    doing more things
    doing extra things
} 
"
    cat "${file1}"

echo "
other code2()
{
    creating other things
    creating more things
    creating extra things
} 
"
} >>"${testfile}"

test ${DBG} -eq 1 && echo "fence 3"

###
### Create editing specification file
###
{
    cat "${file1}"
    echo "###REPLACE_BY###"
    cat "${file2}"
} >findrep.txt

test ${DBG} -eq 1 && echo "fence 4"


###
### sed script to create editing instructions to apply aove editing specification file
###
cat >"blockrep.sed" <<"EnDoFiNpUt"
#SOURCE:    https://www.linuxtopia.org/online_books/linux_tool_guides/the_sed_faq/sedfaq4_013.html
#
# filename: blockrep.sed
#   author: Paolo Bonzini
# Requires:
#    (1) blocks to find and replace, e.g., findrep.txt
#    (2) an input file to be changed, input.file
#
# blockrep.sed creates a second sed script, custom.sed,
# to find the lines above the row of 4 hyphens, globally
# replacing them with the lower block of text. GNU sed
# is recommended but not required for this script.
#
# Loop on the first part, accumulating the `from' text
# into the hold space.
:a
/^###REPLACE_BY###$/! {
   # Escape slashes, backslashes, the final newline and
   # regular expression metacharacters.
   s,[/\[.*],\\&,g
   s/$/\\/
   H
   #
   # Append N cmds needed to maintain the sliding window.
   x
   1 s,^.,s/,
   1! s/^/N\
/
   x
   n
   ba
}
#
# Change the final backslash to a slash to separate the
# two sides of the s command.
x
s,\\$,/,
x
#
# Until EOF, gather the substitution into hold space.
:b
n
s,[/\],\\&,g
$! s/$/\\/
H
$! bb
#
# Start the RHS of the s command without a leading
# newline, add the P/D pair for the sliding window, and
# print the script.
g
s,/\n,/,
s,$,/\
P\
D,p
#---end of script---
EnDoFiNpUt

test ${DBG} -eq 1 && echo "fence 5"


sed --debug -nf blockrep.sed findrep.txt >custom.sed
test ${DBG} -eq 1 && echo "fence 6"

if [ -s custom.sed ]
then
    more custom.sed
    echo -e "\t Hit return to continue ..." >&2
    read k <&2
else
    echo -e "\t Failed to create 'custom.sed'.  Unable to proceed!\n" >&2
    exit 1
fi

testout="Test_OUTPUT.cpp"

sed -f custom.sed "${testfile}" >"${testout}"
test ${DBG} -eq 1 && echo "fence 7"

if [ -s "${testout}" ]
then
    more "${testout}"
else
    echo -e "\t Failed to create '${testout}'.\n" >&2
    exit 1
fi

不幸的是，他们提出的似乎不起作用。 我希望有类似 bash 的“set -x”的命令扩展/报告 sed 执行到 stderr，但我还没有找到类似的东西。

上面的执行日志如下：

fence 1
fence 2
fence 3
fence 4
fence 5
sed: file blockrep.sed line 19: unterminated `s' command
fence 6
     Failed to create 'custom.sed'.  Unable to proceed!

也许那里的专家可以解决导入的blockrep.sed脚本中的逻辑错误...因为即使提供了所有评论，我也无法全神贯注地修复它。

我公开证明我对 sed 的知识和使用都非常简单/有限。我无法开始理解那个“ blockrep.sed ”脚本是如何尝试做它声称的，只是它说明findrep.txt的所有内容，在定义的分隔符字符串“ ###REPLACE_BY### ”之前，将被同一分隔符下方的所有内容替换。

在我看来，linuxtopia 指南确定的方法将具有广泛的应用，并且对包括 OP 和我自己在内的许多人都有好处。

Answer 1

我对blockrep.sed脚本的部分进行了离散化，以查看是否可以确定故障源。 虽然这在表面上没有逻辑上的区别，但它确实创建了一个功能良好且格式正确的结构......它确实创建了一个可用的custom.sed ，但只有在我删除了执行blockrep.sed的--debug选项之后。 这是必需的，因为 degug 信息不会发送到 stderr，而是与 stdout 内联！！！ 我不知道将其归类为错误。

脚本的工作版本如下：

#!/bin/bash

DBG=1

file1=""
file2=""
#divider=""
doReview=0
while [ $# -gt 0 ]
do
    case $1 in
        --old_pattern ) file1="$2" ; shift ; shift ;;
        --new_pattern ) file2="$2" ; shift ; shift ;; 
        #--pattern_sep ) divider="$2" ; shift ; shift ;;    ### Not yet implemented
        --review ) doReview=1 ; shift ;;
        * ) echo "\n invalid option used on command line.  Only valid options: [ --old_pattern {textfile1} | --new_pattern {textfile2} ] \n Bye!\n" ; exit 1 ;;
    esac
done

###
### Code segment to be replaced
###
if [ -z "${file1}" ]
then
file1="File1.cpp"
rm -f "${file1}"
cat >"${file1}" <<"EnDoFiNpUt"
void Component::initialize()
{
    my_component = new ComponentClass();
}
EnDoFiNpUt

test ${DBG} -eq 1 && echo "fence 1"
fi

###
### Code segment to be used as replacement
###
if [ -z "${file2}" ]
then
file2="File2.cpp"
rm -f "${file2}"
cat >"${file2}" <<"EnDoFiNpUt"
void Component::initialize()
{
    if (doInit)
    {
        my_component = new ComponentClass();
    }
    else
    {
        my_component.ptr = null;
    }
}
EnDoFiNpUt

test ${DBG} -eq 1 && echo "fence 2"
fi

###
### Create demo input file
###
testfile="Test_INPUT.cpp"
rm -f "${testfile}"
{
    echo "
other code1()
{
    doing other things
    doing more things
    doing extra things
} 
"
    cat "${file1}"

echo "
other code2()
{
    creating other things
    creating more things
    creating extra things
} 
"
} >>"${testfile}"

test ${DBG} -eq 1 && echo "fence 3"

###
### Create editing specification file
###
{
    cat "${file1}"
    echo "###REPLACE_BY###"
    cat "${file2}"
} >findrep.txt

test ${DBG} -eq 1 && echo "fence 4"


###
### sed script to create editing instructions to apply above editing specification file
if [ ! -s "blockrep.sed" ]
then
cat >"blockrep.sed" <<"EnDoFiNpUt"
#SOURCE:    https://www.linuxtopia.org/online_books/linux_tool_guides/the_sed_faq/sedfaq4_013.html
#
# filename: blockrep.sed
#   author: Paolo Bonzini
# Requires:
#    (1) blocks to find and replace, e.g., findrep.txt
#    (2) an input file to be changed, input.file
#
# blockrep.sed creates a second sed script, custom.sed,
# to find the lines above the row of 4 hyphens, globally
# replacing them with the lower block of text. GNU sed
# is recommended but not required for this script.
#
# Loop on the first part, accumulating the `from' text
# into the hold space.
##############################################################################
### Original coding from linuxtopia
##############################################################################
### :markerA
### /^###REPLACE_BY###$/! {
###     # Escape slashes, backslashes, the final newline and
###     # regular expression metacharacters.
###     s,[/\[.*],\\&,g
###     ### add backslash to end of line (to avoid having sed think of as end of command input
###     s,$,\\,
###     H
###     #
###     # Append N cmds needed to maintain the sliding window.
###     x
###     1 s,^.,s/,
###     1! s,^,N\
### ,
###     x
###     n
###     b markerA
### }
##############################################################################
### Discretized version of coding
##############################################################################
:markerA
/^###REPLACE_BY###$/! {
    #
    # Escape slashes
    s,[/],\\&,g
    #
    # Escape backslashes
    s,[\],\\&,g
    #
    # Escape regular expression metacharacters
    s,[[],\\&,g
    s,[.],\\&,g
    s,[*],\\&,g
    #
    # Escape the final newline
    #   add backslash to end of line (to avoid having sed 
    #   think of as end of command input
    s,$,\\,
    H
    #
    # Append N cmds needed to maintain the sliding window.
    x
    1 s,^.,s/,
    1! s,^,N\
,
    x
    n
    b markerA
}
##############################################################################
#
# Change the final backslash to a slash to separate the
# two sides of the s command.
x
s,\\$,/,
x
#
# Until EOF, gather the substitution into hold space.
:markerB
n
s,[/],\\&,g
s,[\],\\&,g
$! s,$,\\,
H
$! b markerB
#
# Start the RHS of the s command without a leading
# newline, add the P/D pair for the sliding window, and
# print the script.
g
s,/\n,/,
s,$,/\
P\
D,p
#---end of script---
EnDoFiNpUt
fi

test ${DBG} -eq 1 && echo "fence 5"


rm -fv custom.sed custom.err
#sed --debug -f blockrep.sed findrep.txt >custom.sed 2>custom.err
sed -nf blockrep.sed findrep.txt >custom.sed 2>custom.err
if [ -s custom.err ]
then
    if [ ${doReview} -eq 1 ]
    then
        cat custom.err
    fi
fi
test ${DBG} -eq 1 && echo "fence 6"

if [ -s custom.sed ]
then
    if [ ${doReview} -eq 1 ]
    then
        more custom.sed
        echo -e "\t Hit return to continue ..." >&2
        read k <&2
    fi
else
    echo -e "\t Failed to create 'custom.sed'.  Unable to proceed!\n" >&2
    exit 1
fi

testout="Test_OUTPUT.cpp"

sed -f custom.sed "${testfile}" >"${testout}"
test ${DBG} -eq 1 && echo "fence 7"

if [ -s "${testout}" ]
then
    if [ ${doReview} -eq 1 ]
    then
        more "${testout}"
    fi
else
    echo -e "\t Failed to create '${testout}'.\n" >&2
    exit 1
fi

exit

结果 session output 是

fence 1
fence 2
fence 3
fence 4
fence 5
removed 'custom.sed'
removed 'custom.err'
fence 6
N
N
N
s/void Component::initialize()\
{\
    my_component = new ComponentClass();\
}/void Component::initialize()\
{\
    if (doInit)\
    {\
        my_component = new ComponentClass();\
    }\
    else\
    {\
        my_component.ptr = null;\
    }\
}/
P
D
     Hit return to continue ...

fence 7

other code1()
{
    doing other things
    doing more things
    doing extra things
} 

void Component::initialize()
{
    if (doInit)
    {
        my_component = new ComponentClass();
    }
    else
    {
        my_component.ptr = null;
    }
}

other code2()
{
    creating other things
    creating more things
    creating extra things
} 

这是最初的意图。 成功！