Search group in bin text with regex - regex

Question

I need to found the groups in a big text by knowing of:
Word that define the start of a group
Word contained in the group
Word that define the finish of group group
the start word is : begin
the contained word is: 536916223
the finish word is: end
On the text , in the bottom, I need to find 2 groups..
I have tried to use:
\bbegin.*(\n*.*)*536916223(\n*.*)*\bbegin
but if I will be try to use the previous regex on the site "http://regexr.com/"
it respond with timeout... and I think the regex is not very good :(
The text is:
begin active link
export-version : 11
actlink-order : 2
wk-conn-type : 1
schema-name : HelpDesk
actlink-mask : 1
actlink-control: 750000002
enable : 1
action {
set-field : 0\536916222\101\4\1\1\
}
errhandler-name:
end
begin active link
export-version : 11
actlink-order : 2
wk-conn-type : 1
schema-name : HelpDesk
actlink-mask : 1
actlink-control: 610000092
enable : 1
permission : 0
action {
id : 536916223
focus : 0
access-opt : 1
option : 0
}
action {
set-field : 0\536916222\101\4\1\1\
}
errhandler-opt : 0
errhandler-name:
end
begin active link
actlink-order : 12
wk-conn-type : 1
schema-name : HelpDesk
actlink-mask : 2064
enable : 1
permission : 0
action {
id : 536916223
focus : 0
access-opt : 1
option : 0
}
action {
set-field : 0\536916222\101\4\1\1\
}
errhandler-opt : 0
errhandler-name:
end
Can someone suggest me a optimize regex for this work?
Regards,
Vincenzo

Answer 1

Use an unrolled tempered greedy token:
/\bbegin.*(?:\n(?!begin|end(?:$|\n)).*)*\b536916223\b.*(?:\n(?!begin|end(?:$|\n)).*)*\nend/g
or a shorter version if we add MULTILINE modifier:
/^begin.*(?:\n(?!begin|end$).*)*\b536916223\b.*(?:\n(?!begin|end$).*)*\nend$/gm
See the regex demo (a version with MULTILINE modifier)
Details:
\bbegin - a word begin (a word boundary \b can be added after it for surer matches)
.* - the rest of the line after begin
(?:\n(?!begin|end(?:$|\n)).*)* - the unrolled tempered greedy token (?:(?!\n(?:begin|end(?:$|\n)))[\s\S])* matching any sequence but begin at the beginning of a line and end as a whole line
\b536916223\b - the whole word 536916223
.* - the rest of the line after the number
(?:\n(?!begin|end(?:$|\n)).*)* - another unrolled tempered greedy token
\nend - the end word after a newline (a (?:$|\n) can be added after it for surer matches)

Answer 2

The .*(\n*.*)* part is a bit complicated and results in many backtrack.
Since . does not match whitespace character, we can use a global wildcard such as [\S\s] to match any character. Another possible improvement (and possibly correction) is to use lazy match, i.e. *?
The following pattern seems to work fine
\bbegin[\S\s]*?536916223[\S\s]*?\bend

Answer 3

Regex (with m modifier set):
^begin(?:(?!^end)[\s\S])*?536916223[\s\S]*?end
Explanation:
^begin # Match `begin` at start of line
(?: # Start of non-capturing group (a)
(?!^end)[\s\S] # A character which is not followed by `end` delimiter
)*? # Zero or more times (un-greedy)
536916223 # Up to special word
[\s\S]*? # Match any other characters
end # Up to first `end` delimiter
Live demo
Much more efficient version - (with m modifier set):
^begin.*(?:\n(?!^end).*)*536916223(?:.*\n)*?^end
Live demo