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Diffstat (limited to 'src/string_view.h')
-rw-r--r-- | src/string_view.h | 77 |
1 files changed, 0 insertions, 77 deletions
diff --git a/src/string_view.h b/src/string_view.h deleted file mode 100644 index e29414b5..00000000 --- a/src/string_view.h +++ /dev/null @@ -1,77 +0,0 @@ -// Copyright 2019 Roman Perepelitsa. -// -// This file is part of GitStatus. -// -// GitStatus is free software: you can redistribute it and/or modify -// it under the terms of the GNU General Public License as published by -// the Free Software Foundation, either version 3 of the License, or -// (at your option) any later version. -// -// GitStatus is distributed in the hope that it will be useful, -// but WITHOUT ANY WARRANTY; without even the implied warranty of -// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -// GNU General Public License for more details. -// -// You should have received a copy of the GNU General Public License -// along with GitStatus. If not, see <https://www.gnu.org/licenses/>. - -#ifndef ROMKATV_GITSTATUS_STRING_VIEW_H_ -#define ROMKATV_GITSTATUS_STRING_VIEW_H_ - -#include <algorithm> -#include <cstddef> -#include <cstring> -#include <ostream> -#include <string> - -namespace gitstatus { - -// WARNING: StringView must not have embedded null characters. Violations cause UB. -struct StringView { - StringView() : StringView("") {} - - // Requires: !memchr(s.data(), 0, s.size()). - // - // WARNING: The existence of this requirement and the fact that this constructor is implicit - // means it's dangerous to have std::string instances with embedded null characters anywhere - // in the program. If you have an std::string `s` with embedded nulls, an innocent-looking - // `F(s)` might perform an implicit conversion to StringView and land you squarely in the - // Undefined Behavior land. - StringView(const std::string& s) : StringView(s.c_str(), s.size()) {} - - // Requires: !memchr(ptr, 0, len). - StringView(const char* ptr, size_t len) : ptr(ptr), len(len) {} - - // Requires: end >= begin && !memchr(begin, 0, end - begin). - StringView(const char* begin, const char* end) : StringView(begin, end - begin) {} - - // Requires: strchr(s, 0) == s + N. - template <size_t N> - StringView(const char (&s)[N]) : StringView(s, N - 1) { - static_assert(N, ""); - } - - // Explicit because it's the only constructor that isn't O(1). - // Are you sure you don't already known the strings's length? - explicit StringView(const char* ptr) : StringView(ptr, ptr ? std::strlen(ptr) : 0) {} - - bool StartsWith(StringView prefix) const { - return len >= prefix.len && !std::memcmp(ptr, prefix.ptr, prefix.len); - } - - bool EndsWith(StringView suffix) const { - return len >= suffix.len && !std::memcmp(ptr + (len - suffix.len), suffix.ptr, suffix.len); - } - - const char* ptr; - size_t len; -}; - -inline std::ostream& operator<<(std::ostream& strm, StringView s) { - if (s.ptr) strm.write(s.ptr, s.len); - return strm; -} - -} // namespace gitstatus - -#endif // ROMKATV_GITSTATUS_STRING_VIEW_H_ |