duckstation/dep/rapidyaml/include/c4/std/string_view.hpp

72 lines
2.8 KiB
C++

#ifndef _C4_STD_STRING_VIEW_HPP_
#define _C4_STD_STRING_VIEW_HPP_
/** @file string_view.hpp */
#ifndef C4CORE_SINGLE_HEADER
#include "c4/language.hpp"
#endif
#if (C4_CPP >= 17 && defined(__cpp_lib_string_view))
#ifndef C4CORE_SINGLE_HEADER
#include "c4/substr.hpp"
#endif
#include <string_view>
namespace c4 {
//-----------------------------------------------------------------------------
/** create a csubstr from an existing std::string_view. */
C4_ALWAYS_INLINE c4::csubstr to_csubstr(std::string_view s) noexcept
{
return c4::csubstr(s.data(), s.size());
}
//-----------------------------------------------------------------------------
C4_ALWAYS_INLINE bool operator== (c4::csubstr ss, std::string_view s) { return ss.compare(s.data(), s.size()) == 0; }
C4_ALWAYS_INLINE bool operator!= (c4::csubstr ss, std::string_view s) { return ss.compare(s.data(), s.size()) != 0; }
C4_ALWAYS_INLINE bool operator>= (c4::csubstr ss, std::string_view s) { return ss.compare(s.data(), s.size()) >= 0; }
C4_ALWAYS_INLINE bool operator> (c4::csubstr ss, std::string_view s) { return ss.compare(s.data(), s.size()) > 0; }
C4_ALWAYS_INLINE bool operator<= (c4::csubstr ss, std::string_view s) { return ss.compare(s.data(), s.size()) <= 0; }
C4_ALWAYS_INLINE bool operator< (c4::csubstr ss, std::string_view s) { return ss.compare(s.data(), s.size()) < 0; }
C4_ALWAYS_INLINE bool operator== (std::string_view s, c4::csubstr ss) { return ss.compare(s.data(), s.size()) == 0; }
C4_ALWAYS_INLINE bool operator!= (std::string_view s, c4::csubstr ss) { return ss.compare(s.data(), s.size()) != 0; }
C4_ALWAYS_INLINE bool operator<= (std::string_view s, c4::csubstr ss) { return ss.compare(s.data(), s.size()) >= 0; }
C4_ALWAYS_INLINE bool operator< (std::string_view s, c4::csubstr ss) { return ss.compare(s.data(), s.size()) > 0; }
C4_ALWAYS_INLINE bool operator>= (std::string_view s, c4::csubstr ss) { return ss.compare(s.data(), s.size()) <= 0; }
C4_ALWAYS_INLINE bool operator> (std::string_view s, c4::csubstr ss) { return ss.compare(s.data(), s.size()) < 0; }
//-----------------------------------------------------------------------------
/** copy an std::string_view to a writeable substr */
inline size_t to_chars(c4::substr buf, std::string_view s)
{
C4_ASSERT(!buf.overlaps(to_csubstr(s)));
size_t sz = s.size();
size_t len = buf.len < sz ? buf.len : sz;
// calling memcpy with null strings is undefined behavior
// and will wreak havoc in calling code's branches.
// see https://github.com/biojppm/rapidyaml/pull/264#issuecomment-1262133637
if(len)
{
C4_ASSERT(s.data() != nullptr);
C4_ASSERT(buf.str != nullptr);
memcpy(buf.str, s.data(), len);
}
return sz; // return the number of needed chars
}
} // namespace c4
#endif // C4_STRING_VIEW_AVAILABLE
#endif // _C4_STD_STRING_VIEW_HPP_