Re: Fix possible bogus array out of bonds (src/backend/access/brin/brin_minmax_multi.c)

Em seg., 5 de set. de 2022 às 10:40, David Rowley <dgrowleyml(at)gmail(dot)com>
escreveu:

> On Mon, 5 Sept 2022 at 22:15, David Rowley <dgrowleyml(at)gmail(dot)com> wrote:
> > On Sat, 3 Sept 2022 at 00:37, Ranier Vilela <ranier(dot)vf(at)gmail(dot)com> wrote:
> > > 6. Avoid overhead when using unnecessary StringInfoData to convert
> Datum a to Text b.
> >
> > I've ripped out #4 and #6 for now. I think we should do #6 in master
> > only, probably as part of a wider cleanup of StringInfo misusages.
>
> I've attached a patch which does various other string operation cleanups.
>
> * This changes cstring_to_text() to use cstring_to_text_with_len when
> we're working with a StringInfo and can just access the .len field.
> * Uses appendStringInfoString instead of appendStringInfo when there
> is special formatting.
> * Uses pstrdup(str) instead of psprintf("%s", str). In many cases
> this will save a bit of memory
> * Uses appendPQExpBufferChar instead of appendPQExpBufferStr() when
> appending a 1 byte string.
> * Uses appendStringInfoChar() instead of appendStringInfo() when no
> formatting and string is 1 byte.
> * Uses appendStringInfoChar() instead of appendStringInfoString() when
> string is 1 byte.
> * Uses appendPQExpBuffer(b , ...) instead of appendPQExpBufferStr(b, "%s"
> ...)
>
> I'm aware there are a few other places that we could use
> cstring_to_text_with_len() instead of cstring_to_text(). For example,
> using the return value of snprintf() to obtain the length. I just
> didn't do that because we need to take care to check the return value
> isn't -1.
>
> My grep patterns didn't account for these function calls spanning
> multiple lines, so I may have missed a few.
>
I did a search and found a few more places.
v1 attached.

regards,
Ranier Vilela