On Tue, Jan 28, 2014, Adam M wrote: > Hi, > > I'm reading the documentation for ERR_get_error_line_data() here: > http://www.openssl.org/docs/crypto/ERR_get_error.html > > The comments say that 'data' is dynamically allocated with > OPENSSL_malloc() if the ERR_TXT_MALLOCED bit is set in 'flags'. I > presume this means that we need to call OPENSSL_free() to free 'data', > but the documentation isn't clear on that. > > I'm running into two issues in this regard. For one, 'data' is a 'const > char*', but OPENSSL_free() takes a 'void*', so we get a type mismatch. > See my sample code here, which includes the compiler error message: > http://pastebin.com/VNdkwf0G > > The second issue is that I've been looking around on the web (in > particular on Ohloh) for usage of ERR_get_error_line_data(), and no one > seems to be checking for the ERR_TXT_MALLOCED bit in 'flags'. Maybe > doing so isn't necessary, but the documentation seems to suggest that it > is. > > Can someone please help clarify what exactly to do here? >
You can see and example of how it is used internally in the library in crypto/err/err_prn.c all you need to check is that ERR_TXT_STRING is set. The flag ERR_TXT_MALLOCED is an internal flag which indicates whether the string should be freed when the error queue is emptied: applications must not free the string themselves. Steve. -- Dr Stephen N. Henson. OpenSSL project core developer. Commercial tech support now available see: http://www.openssl.org ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org
