CVS commit: src/sys/kern

["Emmanuel Dreyfus" <manu%netbsd.org@localhost>]

Module Name:    src
Committed By:   manu
Date:           Thu Jan 31 02:27:06 UTC 2019

Modified Files:
        src/sys/kern: vfs_syscalls.c

Log Message:
Do not resolve fdat for openat(2) if path is absolute

Opengroup says "The openat() function shall be equivalent to the open() function except in the case where path specifies a relative path", but
says nothing about fdat usage when path is absolute;
https://pubs.opengroup.org/onlinepubs/9699919799/functions/open.html

 We used to always reslove fdat, leading to error if it was invalid (e.g.: -1). That caused portability problem with other systems that
 just ignore it. See discussion in a pull request to work around that
 problem with MariaDB: https://github.com/MariaDB/server/pull/838

 We fix the problem by ignoring fdat when path is absolute.


To generate a diff of this commit:
cvs rdiff -u -r1.520 -r1.521 src/sys/kern/vfs_syscalls.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.