pgsql: Upgrade BufFile to use int64 for byte positions

Started by Michael Paquier6 months ago1 messagescomitters

michael@paquier.xyz

6 months ago

Upgrade BufFile to use int64 for byte positions

This change has the advantage of removing some weird type casts, caused
by offset calculations based on pgoff_t but saved as int (on older
branches we use off_t, which could be 4 or 8 bytes depending on the
environment). These are safe currently because capped by
MAX_PHYSICAL_FILESIZE, but we would run into problems when to make
MAX_PHYSICAL_FILESIZE larger or allow callers of these routines to use a
larger physical max size on demand.

While on it, this improves BufFileDumpBuffer() so as we do not use an
offset for "availbytes". It is not a file offset per-set, but a number
of available bytes.

This change should lead to no functional changes.

Author: Chao Li <li.evan.chao@gmail.com>
Discussion: /messages/by-id/aUStrqoOCDRFAq1M@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bde3a4616072534fd03c75f9019d5165665ed211

Modified Files
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src/backend/storage/file/buffile.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)