fish-shell/cmake/checks/mbrtowc_invalid_utf8.cpp
Mahmoud Al-Qudsi 1365379518 Optimize away a str2wcs_internal check
str2wcs_internal is one of worst hot paths in the codebase, and this
particular check can be optimized away for non-macOS hosts at compile
time.
2020-09-07 18:05:18 -05:00

19 lines
505 B
C++

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cwchar>
// Check whether the runtime mbrtowc implementation attempts to encode
// invalid UTF-8 values.
int main() {
// TODO: I'm not sure how to enforce a UTF-8 locale without overriding the language
char sample[] = "hello world";
sample[0] |= 0xF8;
wchar_t wsample[100] {};
std::mbstate_t state = std::mbstate_t();
int res = std::mbrtowc(wsample, sample, strlen(sample), &state);
return res < 0 ? 0 : 1;
}