Fix signed/unsigned mismatch in file_stdio::seek #1687
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basiliscos
reviewed
Aug 24, 2019
| @@ -241,7 +241,7 @@ seek(std::uint64_t offset, error_code& ec) | |||
| ec = make_error_code(errc::bad_file_descriptor); | |||
| return; | |||
| } | |||
| if(offset > (std::numeric_limits<long>::max)()) | |||
| if(offset > (std::numeric_limits<unsigned long>::max)()) | |||
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I think it should be std::uint64_t instead of unsigned long
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Hmm... I don't think so. stdio (e.g. FILE*) only supports 32 bit offsets: https://en.cppreference.com/w/cpp/io/c/fseek
If you want support for large files you have to use one of the platform-specific implementations.
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But if the input argument type to seek is std::uint64_t why should we care?
The warning is quite annoying with -Wall flag.
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I misunderstood that check earlier. Updated the change to cast the std::numeric_limits value into a std::uint64_t instead.
vinniefalco
reviewed
Aug 25, 2019
| @@ -241,7 +241,7 @@ seek(std::uint64_t offset, error_code& ec) | |||
| ec = make_error_code(errc::bad_file_descriptor); | |||
| return; | |||
| } | |||
| if(offset > (std::numeric_limits<long>::max)()) | |||
| if(offset > static_cast<std::uint64_t>(std::numeric_limits<long>::max())) | |||
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This looks right now, thanks
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This fixes a C4388 warning when compiling with MSVC.