pgsql: Fix overflow in parsing of positional parameter

Fix overflow in parsing of positional parameter

Replace atol with pg_strtoint32_safe in the backend parser and with
strtoint in ECPG to reject overflows when parsing the number of a
positional parameter. With atol from glibc, parameters $2147483648 and
$4294967297 turn into $-2147483648 and $1, respectively.

Author: Erik Wienhold <ewie(at)ewie(dot)name>
Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>
Reviewed-by: Peter Eisentraut <peter(at)eisentraut(dot)org>
Reviewed-by: Alexander Lakhin <exclusion(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/5d216d1c-91f6-4cbe-95e2-b4cbd930520c(at)ewie(dot)name

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d35cd061998434747c0d1c0f6f2aa1f736f0edb4

Modified Files
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src/backend/parser/scan.l | 8 +++++++-
src/interfaces/ecpg/preproc/pgc.l | 8 +++++++-
src/test/regress/expected/numerology.out | 4 ++++
src/test/regress/sql/numerology.sql | 1 +
4 files changed, 19 insertions(+), 2 deletions(-)