Am 10.10.2014 um 20:50 schröbte Hisham: > On 10 October 2014 15:20, Tomas Guisasola Gorham > <to...@tecgraf.puc-rio.br> wrote: >> Hi Hisham and Philipp
Hi! >> >> I am not sure the pull request is a safe implementation since >> an error (not enough memory?) could occur after the malloc and before >> the free... There is no way to let the compiler accept the problematic >> construction? It would be not only safe but also a simpler code to read >> and maintain :-) > > The current construct is not safer: if it runs out of stack space then > it will crash just like not checking the return of malloc would (and > running out of stack is more common than running out of heap space). > The proposed patch with a one-line addition to check the malloc would > make the code safer[*] and not that uglier: if (!to) return 0; That's what the mysql driver does: `malloc`, check for NULL, and `free` later. However, I still like my proposal better: use `lua_newuserdata` for allocating temporary storage. You don't need to check for NULL because `lua_newuserdata` would raise an error, you don't have to `free`, and you can't leak memory even if the `lua_pushlstring` `longjmp`s because the garbage collector will reclaim the memory eventually. > > -- Hisham Philipp > [*] in principle, because making an entire library resilient to > out-of-memory failures is usually a lot of work... Not if you do it right from the beginning. Having programmed in C++ usually helps, because you have a clear idea of object ownership, and Lua errors in combination with the Lua stack and the GC is a lot like C++ exceptions with automatic destructors. ------------------------------------------------------------------------------ Meet PCI DSS 3.0 Compliance Requirements with EventLog Analyzer Achieve PCI DSS 3.0 Compliant Status with Out-of-the-box PCI DSS Reports Are you Audit-Ready for PCI DSS 3.0 Compliance? Download White paper Comply to PCI DSS 3.0 Requirement 10 and 11.5 with EventLog Analyzer http://p.sf.net/sfu/Zoho _______________________________________________ Luarocks-developers mailing list Luarocks-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/luarocks-developers
