https://regex101.com/r/DPKWuX/5/tests

2018-02-12 CoreText crash fix.regex

{
(?#
  # Adapted for PHP by Paul Buonopane
  # Based heavily on the following works:
  #  - https://manishearth.github.io/blog/2018/02/15/picking-apart-the-crashing-ios-string/
  #  - https://github.com/hackbunny/viramarama
  #
  # This PHP regex will match any string that contains Indic character
  # combinations known to crash many iOS applications as of 11.2.5 and certain
  # macOS applications as of 10.13.3.
  #
  # IMPORTANT: This will only work if you use the `x` and `u` modifiers.
  #            Example: "/regex-goes-here/xu"
  #
  # COMPATIBILITY: While PHP does use PCRE, the `u` modifier isn't technically
  #                Perl-compatible.  For this to work without the `u` modifier,
  #                the regex would need to be adapted to use | instead of [],
  #                as all of these characters are multibyte in all popular web
  #                encodings, e.g. UTF-8.
  #
  # Tracked By: rdar://37458268
  #             https://openradar.appspot.com/37458268
  # Date Originated: 2018-02-12
  # CVE ID: Unknown as of writing
  #)

(?(DEFINE)
	(?<zwnj> ‌(?# You can't see me, but I'm here!))
	(?<devanagari_virama> ्)
	(?<devanagari_consonants> [कखगघङहचछजझञयशटठडढणरषतथदधनलसपफबभमव])
	(?<devanagari_sj_consonants> [र])
	(?<devanagari_pj_pairs> र(?&devanagari_virama)र)
	(?<devanagari_vowels> [ऺऻािीुूृॄॅॆेैॉॊोौॎॏॕॖॗॢॣ])

	(?<bengali_virama> ্)
	(?<bengali_consonants> [কখগঘঙচছজঝঞটঠডঢণতথদধনপফবভমযরৰলৱশষসহ])
	(?<bengali_sj_consonants> [যর])
	(?<bengali_pj_pairs> [রৰ](?&bengali_virama)র)
	(?<bengali_vowels> [ািীুূৃৄেৈৢৣ])

	(?<telugu_virama> ్)
	(?<telugu_consonants> [కఖగఘఙచఛజఝఞటఠడఢణతథదధనపఫబభమయరలవళశషసహఱ])
	(?<telugu_sj_consonants> (?&telugu_consonants))
	(?<telugu_vowels> [ాిీుూృౄెేొోౌౢౣ])
)

(?!(?&devanagari_pj_pairs))
(?&devanagari_consonants)
(?&devanagari_virama)
(?&devanagari_sj_consonants)
(?&zwnj)
(?&devanagari_vowels)

|

(?!(?&bengali_pj_pairs))
(?&bengali_consonants)
(?&bengali_virama)
(?&bengali_sj_consonants)
(?&zwnj)
(?&bengali_vowels)

|

(?&telugu_consonants)
(?&telugu_virama)
(?&telugu_sj_consonants)
(?&zwnj)
(?&telugu_vowels)

(?#
  # The license for the work on which this regex is based is provided below, with an
  # additional note regarding adaptation.
  #
  # Copyright 2018 hackbunny <hackbunny@gmail.com>
  # Adapted for PHP by Paul Buonopane
  # 
  # Permission is hereby granted, free of charge, to any person obtaining a copy of this
  # software and associated documentation files [the "Software"], to deal in the Software
  # without restriction, including without limitation the rights to use, copy, modify,
  # merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
  # permit persons to whom the Software is furnished to do so, subject to the following
  # conditions:
  # 
  # The above copyright notice and this permission notice shall be included in all copies or
  # substantial portions of the Software.
  # 
  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
  # INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  # PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT
  # OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  # OTHER DEALINGS IN THE SOFTWARE.
  #)
}xu

concise.regex

{(?(DEFINE)(?<zwnj>‌)(?<devanagari_virama>्)(?<devanagari_consonants>[कखगघङहचछजझञयशटठडढणरषतथदधनलसपफबभमव])(?<devanagari_sj_consonants>[र])(?<devanagari_pj_pairs>र(?&devanagari_virama)र)(?<devanagari_vowels>[ऺऻािीुूृॄॅॆेैॉॊोौॎॏॕॖॗॢॣ])(?<bengali_virama>্)(?<bengali_consonants>[কখগঘঙচছজঝঞটঠডঢণতথদধনপফবভমযরৰলৱশষসহ])(?<bengali_sj_consonants>[যর])(?<bengali_pj_pairs>[রৰ](?&bengali_virama)র)(?<bengali_vowels>[ািীুূৃৄেৈৢৣ])(?<telugu_virama>్)(?<telugu_consonants>[కఖగఘఙచఛజఝఞటఠడఢణతథదధనపఫబభమయరలవళశషసహఱ])(?<telugu_sj_consonants>(?&telugu_consonants))(?<telugu_vowels>[ాిీుూృౄెేొోౌౢౣ]))(?!(?&devanagari_pj_pairs))(?&devanagari_consonants)(?&devanagari_virama)(?&devanagari_sj_consonants)(?&zwnj)(?&devanagari_vowels)|(?!(?&bengali_pj_pairs))(?&bengali_consonants)(?&bengali_virama)(?&bengali_sj_consonants)(?&zwnj)(?&bengali_vowels)|(?&telugu_consonants)(?&telugu_virama)(?&telugu_sj_consonants)(?&zwnj)(?&telugu_vowels)}u

tests.txt

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