Thread: pgsql: Change regexp engine's ccondissect/crevdissect routines to
pgsql: Change regexp engine's ccondissect/crevdissect routines to
From
tgl@postgresql.org (Tom Lane)
Date:
Log Message: ----------- Change regexp engine's ccondissect/crevdissect routines to perform DFA matching before recursing instead of after. The DFA match eliminates unworkable midpoint choices a lot faster than the recursive check, in most cases, so doing it first can speed things up; particularly in pathological cases such as recently exhibited by Michael Glaesemann. In addition, apply some cosmetic changes that were applied upstream (in the Tcl project) at the same time, in order to sync with upstream version 1.15 of regexec.c. Upstream apparently intends to backpatch this, so I will too. The pathological behavior could be unpleasant if encountered in the field, which seems to justify any risk of introducing new bugs. Tom Lane, reviewed by Donal K. Fellows of Tcl project Tags: ---- REL8_2_STABLE Modified Files: -------------- pgsql/src/backend/regex: regexec.c (r1.27 -> r1.27.4.1) (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/regex/regexec.c?r1=1.27&r2=1.27.4.1)