svn commit: r363679 - in head: contrib/netbsd-tests/lib/libc/regex/data lib/libc/regex

[Li-Wen Hsu]

On Thu, Jul 30, 2020 at 7:22 AM Kyle Evans <kevans at freebsd.org> wrote:
>
> Author: kevans
> Date: Wed Jul 29 23:21:56 2020
> New Revision: 363679
> URL: https://svnweb.freebsd.org/changeset/base/363679
>
> Log:
>   regex(3): Interpret many escaped ordinary characters as EESCAPE
>
>   In IEEE 1003.1-2008 [1] and earlier revisions, BRE/ERE grammar allows for
>   any character to be escaped, but "ORD_CHAR preceded by an unescaped
>   <backslash> character [gives undefined results]".
>
>   Historically, we've interpreted an escaped ordinary character as the
>   ordinary character itself. This becomes problematic when some extensions
>   give special meanings to an otherwise ordinary character
>   (e.g. GNU's \b, \s, \w), meaning we may have two different valid
>   interpretations of the same sequence.
>
>   To make this easier to deal with and given that the standard calls this
>   undefined, we should throw an error (EESCAPE) if we run into this scenario
>   to ease transition into a state where some escaped ordinaries are blessed
>   with a special meaning -- it will either error out or have extended
>   behavior, rather than have two entirely different versions of undefined
>   behavior that leave the consumer of regex(3) guessing as to what behavior
>   will be used or leaving them with false impressions.
>
>   This change bumps the symbol version of regcomp to FBSD_1.6 and provides the
>   old escape semantics for legacy applications, just in case one has an older
>   application that would immediately turn into a pumpkin because of an
>   extraneous escape that's embehttps://ci.freebsd.org/job/FreeBSD-head-amd64-test/16011/testReport/junit/lib.googletest.gtest_main/googletest-port-test/main/dded or otherwise critical to its operation.
>
>   This is the final piece needed before enhancing libregex with GNU extensions
>   and flipping the switch on bsdgrep.
>
>   [1] http://pubs.opengroup.org/onlinepubs/9699919799.2016edition/
>
>   PR:           229925 (exp-run, courtesy of antoine)
>   Differential Revision:        https://reviews.freebsd.org/D10510
>
> Modified:
>   head/contrib/netbsd-tests/lib/libc/regex/data/meta.in
>   head/contrib/netbsd-tests/lib/libc/regex/data/subexp.in
>   head/lib/libc/regex/Symbol.map
>   head/lib/libc/regex/regcomp.c

I think there are 3 test cases need to be modified after this change:

https://ci.freebsd.org/job/FreeBSD-head-amd64-test/16011/testReport/junit/lib.googletest.gtest_main/googletest-port-test/main/
https://ci.freebsd.org/job/FreeBSD-head-amd64-test/16011/testReport/junit/usr.bin.diff/diff_test/side_by_side/
https://ci.freebsd.org/job/FreeBSD-head-amd64-test/16011/testReport/junit/usr.bin.sed/sed2_test/hex_subst/

Please help to check them, thanks!

Li-Wen