pgsql: Return ssize_t in fd.c I/O functions. - Mailing list pgsql-committers

From Thomas Munro
Subject pgsql: Return ssize_t in fd.c I/O functions.
Date
Msg-id E1rgC6A-001azD-IX@gemulon.postgresql.org
Whole thread Raw
List pgsql-committers
Return ssize_t in fd.c I/O functions.

In the past, FileRead() and FileWrite() used types based on the Unix
read() and write() functions from before C and POSIX standardization,
though not exactly (we had int for amount instead of unsigned).  In
commit 2d4f1ba6 we changed to the appropriate standard C types, just
like the modern POSIX functions they wrap, but again not exactly: the
return type stayed as int.  In theory, a ssize_t value could be returned
by the underlying call that is too large for an int.

That wasn't really a live bug, because we don't expect PostgreSQL code
to perform reads or writes of gigabytes, and OSes probably apply
internal caps smaller than that anyway.  This change is done on the
principle that the return might as well follow the standard interfaces
consistently.

Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/1672202.1703441340%40sss.pgh.pa.us

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/653b55b57081dc6fb8c75d61870c5fdc8c8554cc

Modified Files
--------------
src/backend/storage/file/fd.c | 8 ++++----
src/include/storage/fd.h      | 8 ++++----
2 files changed, 8 insertions(+), 8 deletions(-)


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