pgsql: pg_resetwal: Improve numeric command-line argument parsing

pg_resetwal: Improve numeric command-line argument parsing

Check errno after strtoul()/strtol() to handle out of range errors
better.  For out of range, strtoul() returns ULONG_MAX, and the
previous code would proceed with that result.

Reported-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/6a10a211-872b-3c4c-106b-909ae5fefa61%40enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9a6345ed741783e8770ef160e822d2257873adef

Modified Files
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src/bin/pg_resetwal/pg_resetwal.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)