Re: Will the following code cause any memory leak?

From:
"Jim Langston" <tazmaster@rocketmail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Mon, 16 Feb 2009 09:18:10 CST
Message-ID:
<5ybml.7645$FI5.3070@newsfe07.iad>
"Bill David" <billdavidcn@gmail.com> wrote in message
news:66f72ef7-db11-4458-983b-c8368dd196c7@i24g2000prf.googlegroups.com...

I have the following code in my application. But I find it causes a
serious memory leak with a product we are using. Our application is a
plug-in to this product. But we are not sure what's the boost and stdc+
+ library version included by this product.

The following is the code (On Windows, the product should be written
with Visual Studio 2003/2005):
/**
 * @brief Convert modify time string to time_t for easy internal
handling
 * @param str Modify time string returned by HTTP server, e.g. "Fri,
18 Jul 2008 11:53:14 GMT"
 * @return Corresponding time_t result
 */
time_t parseDate(const string& str)
{
    ptime p;
    stringstream ss(str.c_str());
    time_input_facet* timefacet = new time_input_facet("%a, %d %b %Y
%H:%M:%S %z"); // will be automatically deleted by related locale
object


You claim this memory will be automatically deleted by related locate
object, yet you find there is a memory leak. You are not showing the code
where it is deleted. That is most likely your problem, it is in fact not
being deleted.

    ss.imbue(locale(locale::classic(), timefacet));
    ss >> p;

    tm t = to_tm(p);
    return mktime(&t);
}

And we find the problem is caused by
time_input_facet* timefacet = new time_input_facet("%a, %d %b %Y %H:%M:
%S %z");
ss.imbue(locale(locale::classic(), timefacet));
it seems related memory has not been released by locale or some memory
is leaked by time_input_facet.

We have tested above code separately with boost 1.35.0, 1.37.0 and
VS2005 + SP1, it's OK. So can anybody tell me if it's any problem in
above code? Or is it a bug in old version of boost date_time or MS
Visual Studio 2003/2005?
Or is there any other solution to parse a time string like "Fri, 18
Jul 2008 11:53:14 GMT"?


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