Re: [COMMITTERS] pgsql: StrNCpy -> strlcpy (not complete)

On Sat, Feb 10, 2007 at 09:21:04PM -0500, Bruce Momjian wrote:
> Woh.  Peter, you realize one of the reasons we use StrNCpy as a macro is
> for performance.  I don't see strlcpy as a macro.  Are you going to
> change all call locations to strlcpy?  If so, have you measured the
> performance impact?

I think we had this discussion already. strncpy() copies N bytes,
whereas strlcpy() copies only as many bytes as necessary. For short
strings with larger buffers, strlcpy() wins. It's understood that
in many cases in PostgreSQL, the expectation is for short strings,
and it is not required for the later bytes to be '\0'.

I assume Peter is only changing the provably good uses? :-)

Cheers,
mark


> Peter Eisentraut wrote:
> > Log Message:
> > -----------
> > StrNCpy -> strlcpy (not complete)
> > 
> > Modified Files:
> > --------------
> >     pgsql/src/backend/bootstrap:
> >         bootstrap.c (r1.229 -> r1.230)
> >
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/bootstrap/bootstrap.c.diff?r1=1.229&r2=1.230)
> >     pgsql/src/backend/libpq:
> >         crypt.c (r1.72 -> r1.73)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/libpq/crypt.c.diff?r1=1.72&r2=1.73)
> >         hba.c (r1.159 -> r1.160)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/libpq/hba.c.diff?r1=1.159&r2=1.160)
> >         ip.c (r1.39 -> r1.40)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/libpq/ip.c.diff?r1=1.39&r2=1.40)
> >     pgsql/src/backend/nodes:
> >         print.c (r1.83 -> r1.84)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/print.c.diff?r1=1.83&r2=1.84)
> >     pgsql/src/backend/postmaster:
> >         pgarch.c (r1.28 -> r1.29)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/pgarch.c.diff?r1=1.28&r2=1.29)
> >         postmaster.c (r1.518 -> r1.519)
> >
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/postmaster.c.diff?r1=1.518&r2=1.519)
> >     pgsql/src/backend/tcop:
> >         postgres.c (r1.521 -> r1.522)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tcop/postgres.c.diff?r1=1.521&r2=1.522)
> >     pgsql/src/backend/utils/misc:
> >         guc-file.l (r1.46 -> r1.47)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/guc-file.l.diff?r1=1.46&r2=1.47)
> >     pgsql/src/bin/initdb:
> >         initdb.c (r1.131 -> r1.132)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/initdb/initdb.c.diff?r1=1.131&r2=1.132)
> >     pgsql/src/bin/pg_ctl:
> >         pg_ctl.c (r1.77 -> r1.78)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_ctl/pg_ctl.c.diff?r1=1.77&r2=1.78)
> >     pgsql/src/bin/pg_dump:
> >         pg_dumpall.c (r1.89 -> r1.90)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/pg_dumpall.c.diff?r1=1.89&r2=1.90)
> >     pgsql/src/bin/pg_resetxlog:
> >         pg_resetxlog.c (r1.56 -> r1.57)
> >
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_resetxlog/pg_resetxlog.c.diff?r1=1.56&r2=1.57)
> >     pgsql/src/interfaces/libpq:
> >         fe-auth.c (r1.122 -> r1.123)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-auth.c.diff?r1=1.122&r2=1.123)
> >         fe-connect.c (r1.342 -> r1.343)
> >
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-connect.c.diff?r1=1.342&r2=1.343)
> >     pgsql/src/timezone:
> >         pgtz.c (r1.49 -> r1.50)
> >         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/timezone/pgtz.c.diff?r1=1.49&r2=1.50)
> > 
> > ---------------------------(end of broadcast)---------------------------
> > TIP 6: explain analyze is your friend
> 
> -- 
>   Bruce Momjian  <bruce@momjian.us>          http://momjian.us
>   EnterpriseDB                               http://www.enterprisedb.com
> 
>   + If your life is a hard drive, Christ can be your backup. +
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 3: Have you checked our extensive FAQ?
> 
>                http://www.postgresql.org/docs/faq

-- 
mark@mielke.cc / markm@ncf.ca / markm@nortel.com     __________________________
.  .  _  ._  . .   .__    .  . ._. .__ .   . . .__  | Neighbourhood Coder
|\/| |_| |_| |/    |_     |\/|  |  |_  |   |/  |_   | 
|  | | | | \ | \   |__ .  |  | .|. |__ |__ | \ |__  | Ottawa, Ontario, Canada
 One ring to rule them all, one ring to find them, one ring to bring them all                      and in the darkness
bindthem...
 
                          http://mark.mielke.cc/