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Comment by swinglock | Hacker News Reader

I'm surprised curlx_strcopy doesn't return success. Sure you could check if dest[0] != '/0' if you care to, but that's not only clumsy to write but also error prone, and so checking for success is not encouraged.

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I guess the idea is that if the code does not crash at this line:

    DEBUGASSERT(slen < dsize);

it means it succeeded. Although some compilers will remove the assertions in release builds.

I would have preferred an explicit error code though.

assert() is always only compiled if NDEBUG is not defined. I hope DEBUGASSERT is just that too because it really sounds like it, even more so than assert does.

But regardless of whether the assert is compiled or not, its presence strongly signals that "in a C program strcpy should only be used when we have full control of both" is true for this new function as well.

Yeah, thought the same. Expect some CVEs in the future.

What kind of CVE would you expect? The destination buffer will always contain a valid null-terminated string (as long as the buffer size is not zero).

This is especially bizarre given that he explains above that "it is rare that copying a partial string is the right choice" and that the previous solution returned an error...

So now it silently fails and sets dest to an empty string without even partially copying anything!?

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