jsonpath scanner: reentrant scanner
Use the flex %option reentrant to make the generated scanner
reentrant and thread-safe. Note: The parser was already pure.
Simplify flex scan buffer management: Instead of constructing the
buffer from pieces and then using yy_scan_buffer(), we can just use
yy_scan_string(), which does the same thing internally. (Actually, we
use yy_scan_bytes() here because we already have the length.)
Use flex yyextra to handle context information, instead of global
variables. This complements the other changes to make the scanner
reentrant.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Discussion: https://www.postgresql.org/message-id/flat/
eb6faeac-2a8a-4b69-9189-
c33c520e5b7b@eisentraut.org