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