Re: Fix for pg_upgrade's forcing pg_controldata into English

Tom Lane wrote:
> Bruce Momjian <bruce@momjian.us> writes:
> > Tom Lane wrote:
> >> I certainly hope that pg_regress isn't freeing the strings it passes
> >> to putenv() ...
> 
> > pg_regress does not restore these settings (it says with C/English) so
> > the code is different.
> 
> That's not what I'm on about.  You're trashing strings that are part of
> the live environment.  It might accidentally fail to fail for you, if
> your version of free() doesn't immediately clobber the released storage,
> but it's still broken.  Read the putenv() man page.
> 
> + #ifndef WIN32
> + 		char	   *envstr = (char *) pg_malloc(ctx, strlen(var) +
> + 							strlen(val) + 1);
> + 
> + 		sprintf(envstr, "%s=%s", var, val);
> + 		putenv(envstr);
> + 		pg_free(envstr);
>                 ^^^^^^^^^^^^^^^^
> + #else
> + 		SetEnvironmentVariableA(var, val);
> + #endif
> 
> The fact that there is no such free() in pg_regress is not an oversight
> or shortcut.

Interesting.  I did not know this and it was not clear from my manual
page or FreeBSD's manual page, but Linux clearly does this.

Updated patch attached.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +