pgsql: Widen COPY FROM's current-line-number counter from 32 to 64bits

Widen COPY FROM's current-line-number counter from 32 to 64 bits.

Because the code for the HEADER option skips a line when this counter
is zero, a very long COPY FROM WITH HEADER operation would drop a line
every 2^32 lines.  A lesser but still unfortunate problem is that errors
would show a wrong input line number for errors occurring beyond the
2^31'st input line.  While such large input streams seemed impractical
when this code was first written, they're not any more.  Widening the
counter (and some associated variables) to uint64 should be enough to
prevent problems for the foreseeable future.

David Rowley

Discussion: https://postgr.es/m/CAKJS1f88yh-6wwEfO6QLEEvH3BEugOq2QX1TOja0vCauoynmOQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ecac23511e04d96b94705731873fa3d238c41f8d

Modified Files
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src/backend/commands/copy.c | 38 +++++++++++++++++++++-----------------
1 file changed, 21 insertions(+), 17 deletions(-)