Package: wnpp Severity: wishlist Owner: Michael Fladischer <fl...@debian.org> X-Debbugs-Cc: debian-devel@lists.debian.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 * Package name : libvmod-re2 Version : 1.11.0 Upstream Author : 2016, UPLEX Nils Goroll Systemoptimierung * URL : https://code.uplex.de/uplex-varnish/libvmod-re2 * License : BSD-2-clause Programming Lang: C Description : RE2 regular expressions for Varnish Varnish Module (VMOD) for access to the Google RE2 regular expression engine. Varnish VCL uses the PCRE library (Perl Compatible Regular Expressions) for its native regular expressions, which runs very efficiently for many common uses of pattern matching in VCL, as attested by years of successful use of PCRE with Varnish. . But for certain kinds of patterns, the worst-case running time of the PCRE matcher is exponential in the length of the string to be matched. The matcher uses backtracking, implemented with recursive calls to the internal match() function. In principle there is no upper bound to the possible depth of backtracking and recursion, except as imposed by the varnishd runtime parameters pcre_match_limit and pcre_match_limit_recursion; matches fail if either of these limits are met. Stack overflow caused by deep backtracking has occasionally been the subject of varnishd issues. . RE2 differs from PCRE in that it limits the syntax of patterns so that they always specify a regular language in the formally strict sense. Most notably, backreferences within a pattern are not permitted, for example (foo|bar)\1 to match foofoo and barbar, but not foobar or barfoo. See the link in SEE ALSO for the specification of RE2 syntax. . This means that an RE2 matcher runs as a finite automaton, which guarantees linear running time in the length of the matched string. There is no backtracking, and hence no risk of deep recursion or stack overflow. I intend to maintain this package as part of the Varnish Packaging Team. -----BEGIN PGP SIGNATURE----- iQFFBAEBCgAvFiEEqVSlRXW87UkkCnJc/9PIi5l90WoFAmGyZm8RHGZsYWRpQGRl Ymlhbi5vcmcACgkQ/9PIi5l90WpH3Qf/e8G/P2Ezny0BkeLub+m1i2RbZxuUpZwU Ry8UkSbkpU0oMvRsJ6kEqen2YEe9oeD0zm4t5pOGl51XWNOpr8M+7fZr0Vu0cNCw nbKoN41Jaot+nHdYxNiPhkOOcYBK8gcsbeDuB87JXfx4V1l5VfL5bfcU3yiKqEE+ vgYRXx2EFiDsiXXtpxd/sh9rCMfB8Pvky7KFfIMk8sbK0rFPDHbDs4azCkXEqB8g LUFnSCqnqL5oApo3CjFxE7GO3PqcUJhzsQP38HS9d7WLdiaJQsVC88pxMYxodJFQ vTXTXK+CffHaYYA7smO93I7fyX1XGJZ1L3UQ1j+OqfQaDC/OaVF1IQ== =qqVV -----END PGP SIGNATURE-----
