Re: more psprintf() use

On 2014-01-02 09:49:48 +0200, Heikki Linnakangas wrote:
> On 01/02/2014 05:14 AM, Peter Eisentraut wrote:
> >diff --git a/contrib/hstore/hstore_io.c b/contrib/hstore/hstore_io.c
> >index 772a5ca..8331a56 100644
> >--- a/contrib/hstore/hstore_io.c
> >+++ b/contrib/hstore/hstore_io.c
> >@@ -1114,11 +1114,7 @@
> >      HEntry       *entries = ARRPTR(in);
> >
> >      if (count == 0)
> >-    {
> >-        out = palloc(1);
> >-        *out = '\0';
> >-        PG_RETURN_CSTRING(out);
> >-    }
> >+        PG_RETURN_CSTRING("");
> >
> >      buflen = 0;
> 
> Is it legal to return a constant with PG_RETURN_CSTRING? Grepping around, I
> don't see that being done anywhere else, but there are places that do
> PG_RETURN_CSTRING(pstrdup(<constant>))...

I don't see why it wouldn't be legal - constant strings have static
storage duration, i.e. the program lifetime. And I can see nothing that
would allow pfree()ing the return value of cstring returning functions
in the general case.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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