summaryrefslogtreecommitdiffstats
path: root/src/third-party/scnlib/src/reader_int.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/third-party/scnlib/src/reader_int.cpp')
-rw-r--r--src/third-party/scnlib/src/reader_int.cpp372
1 files changed, 372 insertions, 0 deletions
diff --git a/src/third-party/scnlib/src/reader_int.cpp b/src/third-party/scnlib/src/reader_int.cpp
new file mode 100644
index 0000000..9b953d2
--- /dev/null
+++ b/src/third-party/scnlib/src/reader_int.cpp
@@ -0,0 +1,372 @@
+// Copyright 2017 Elias Kosunen
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// This file is a part of scnlib:
+// https://github.com/eliaskosunen/scnlib
+
+#if defined(SCN_HEADER_ONLY) && SCN_HEADER_ONLY
+#define SCN_READER_INT_CPP
+#endif
+
+#include <scn/detail/args.h>
+#include <scn/reader/int.h>
+
+namespace scn {
+ SCN_BEGIN_NAMESPACE
+
+ namespace detail {
+ SCN_NODISCARD static unsigned char _char_to_int(char ch)
+ {
+ static constexpr unsigned char digits_arr[] = {
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 1, 2, 3,
+ 4, 5, 6, 7, 8, 9, 255, 255, 255, 255, 255, 255, 255,
+ 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
+ 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
+ 255, 255, 255, 255, 255, 255, 10, 11, 12, 13, 14, 15, 16,
+ 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
+ 30, 31, 32, 33, 34, 35, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255, 255};
+ return digits_arr[static_cast<unsigned char>(ch)];
+ }
+ SCN_NODISCARD static unsigned char _char_to_int(wchar_t ch)
+ {
+ SCN_GCC_PUSH
+ SCN_GCC_IGNORE("-Wconversion")
+ if (ch >= std::numeric_limits<char>::min() &&
+ ch <= std::numeric_limits<char>::max()) {
+ return _char_to_int(static_cast<char>(ch));
+ }
+ return 255;
+ SCN_GCC_POP
+ }
+
+ template <typename T>
+ template <typename CharT>
+ expected<typename span<const CharT>::iterator>
+ integer_scanner<T>::parse_base_prefix(span<const CharT> s, int& b) const
+ {
+ auto it = s.begin();
+ // If base can be detected, it should start with '0'
+ if (*it == ascii_widen<CharT>('0')) {
+ ++it;
+ if (it == s.end()) {
+ // It's really just 0
+ // Return it to begininng, where '0' is
+ b = -1;
+ return it;
+ }
+ if (*it == ascii_widen<CharT>('x') ||
+ *it == ascii_widen<CharT>('X')) {
+ // Hex: 0x or 0X
+ ++it;
+ if (SCN_UNLIKELY(it == s.end())) {
+ // 0x/0X not a valid number
+ b = -1;
+ return --it;
+ }
+ if (b == 0) {
+ // Detect base
+ b = 16;
+ }
+ else if (b != 16) {
+ // Invalid prefix for base
+ return error(error::invalid_scanned_value,
+ "Invalid base prefix");
+ }
+ }
+ else if (*it == ascii_widen<CharT>('b') ||
+ *it == ascii_widen<CharT>('B')) {
+ // Binary: 0b or 0b
+ ++it;
+ if (SCN_UNLIKELY(it == s.end())) {
+ // 0b/0B not a valid number
+ b = -1;
+ return --it;
+ }
+ if (b == 0) {
+ // Detect base
+ b = 2;
+ }
+ else if (b != 2) {
+ // Invalid prefix for base
+ return error(error::invalid_scanned_value,
+ "Invalid base prefix");
+ }
+ }
+ else if (*it == ascii_widen<CharT>('o') ||
+ *it == ascii_widen<CharT>('O')) {
+ // Octal: 0o or 0O
+ ++it;
+ if (SCN_UNLIKELY(it == s.end())) {
+ // 0o/0O not a valid number
+ b = -1;
+ return --it;
+ }
+ if (b == 0) {
+ // Detect base
+ b = 8;
+ }
+ else if (b != 8) {
+ // Invalid prefix for base
+ return error(error::invalid_scanned_value,
+ "Invalid base prefix");
+ }
+ }
+ else if (b == 0) {
+ // Starting with only 0 -> octal
+ b = 8;
+ }
+ }
+ if (b == 0) {
+ // None detected, default to 10
+ b = 10;
+ }
+ return it;
+ }
+
+ template <typename T>
+ template <typename CharT>
+ expected<std::ptrdiff_t> integer_scanner<T>::_parse_int(
+ T& val,
+ span<const CharT> s)
+ {
+ SCN_EXPECT(s.size() > 0);
+
+ SCN_MSVC_PUSH
+ SCN_MSVC_IGNORE(4244)
+ SCN_MSVC_IGNORE(4127) // conditional expression is constant
+
+ if (std::is_unsigned<T>::value) {
+ if (s[0] == detail::ascii_widen<CharT>('-')) {
+ return error(error::invalid_scanned_value,
+ "Unexpected sign '-' when scanning an "
+ "unsigned integer");
+ }
+ }
+
+ SCN_MSVC_POP
+
+ T tmp = 0;
+ bool minus_sign = false;
+ auto it = s.begin();
+
+ SCN_GCC_PUSH
+ SCN_GCC_IGNORE("-Wsign-conversion")
+ if (s[0] == ascii_widen<CharT>('-')) {
+ if (SCN_UNLIKELY((format_options & only_unsigned) != 0)) {
+ // 'u' option -> negative values disallowed
+ return error(error::invalid_scanned_value,
+ "Parsed negative value when type was 'u'");
+ }
+ minus_sign = true;
+ ++it;
+ }
+ else if (s[0] == ascii_widen<CharT>('+')) {
+ ++it;
+ }
+ SCN_GCC_POP
+ if (SCN_UNLIKELY(it == s.end())) {
+ return error(error::invalid_scanned_value,
+ "Expected number after sign");
+ }
+
+ // Format string was 'i' or empty -> detect base
+ // or
+ // allow_base_prefix (skip 0x etc.)
+ if (SCN_UNLIKELY(base == 0 ||
+ (format_options & allow_base_prefix) != 0)) {
+ int b{base};
+ auto r = parse_base_prefix<CharT>({it, s.end()}, b);
+ if (!r) {
+ return r.error();
+ }
+ if (b == -1) {
+ // -1 means we read a '0'
+ val = 0;
+ return ranges::distance(s.begin(), r.value());
+ }
+ if (b != 10 && base != b && base != 0) {
+ return error(error::invalid_scanned_value,
+ "Invalid base prefix");
+ }
+ if (base == 0) {
+ base = static_cast<uint8_t>(b);
+ }
+ it = r.value();
+ }
+
+ SCN_GCC_PUSH
+ SCN_GCC_IGNORE("-Wconversion")
+ SCN_GCC_IGNORE("-Wsign-conversion")
+ SCN_GCC_IGNORE("-Wsign-compare")
+
+ SCN_CLANG_PUSH
+ SCN_CLANG_IGNORE("-Wconversion")
+ SCN_CLANG_IGNORE("-Wsign-conversion")
+ SCN_CLANG_IGNORE("-Wsign-compare")
+
+ SCN_ASSUME(base > 0);
+
+ SCN_CLANG_PUSH_IGNORE_UNDEFINED_TEMPLATE
+ auto r = _parse_int_impl(tmp, minus_sign, make_span(it, s.end()));
+ SCN_CLANG_POP_IGNORE_UNDEFINED_TEMPLATE
+ if (!r) {
+ return r.error();
+ }
+ it = r.value();
+ if (s.begin() == it) {
+ return error(error::invalid_scanned_value, "custom::read_int");
+ }
+ val = tmp;
+ return ranges::distance(s.begin(), it);
+
+ SCN_CLANG_POP
+ SCN_GCC_POP
+ }
+
+ template <typename T>
+ template <typename CharT>
+ expected<typename span<const CharT>::iterator>
+ integer_scanner<T>::_parse_int_impl(T& val,
+ bool minus_sign,
+ span<const CharT> buf) const
+ {
+ SCN_GCC_PUSH
+ SCN_GCC_IGNORE("-Wconversion")
+ SCN_GCC_IGNORE("-Wsign-conversion")
+ SCN_GCC_IGNORE("-Wsign-compare")
+
+ SCN_CLANG_PUSH
+ SCN_CLANG_IGNORE("-Wconversion")
+ SCN_CLANG_IGNORE("-Wsign-conversion")
+ SCN_CLANG_IGNORE("-Wsign-compare")
+
+ SCN_MSVC_PUSH
+ SCN_MSVC_IGNORE(4018) // > signed/unsigned mismatch
+ SCN_MSVC_IGNORE(4389) // == signed/unsigned mismatch
+ SCN_MSVC_IGNORE(4244) // lossy conversion
+
+ using utype = typename std::make_unsigned<T>::type;
+
+ const auto ubase = static_cast<utype>(base);
+ SCN_ASSUME(ubase > 0);
+
+ constexpr auto uint_max = static_cast<utype>(-1);
+ constexpr auto int_max = static_cast<utype>(uint_max >> 1);
+ constexpr auto abs_int_min = static_cast<utype>(int_max + 1);
+
+ const auto cut = div(
+ [&]() -> utype {
+ if (std::is_signed<T>::value) {
+ if (minus_sign) {
+ return abs_int_min;
+ }
+ return int_max;
+ }
+ return uint_max;
+ }(),
+ ubase);
+ const auto cutoff = cut.first;
+ const auto cutlim = cut.second;
+
+ auto it = buf.begin();
+ const auto end = buf.end();
+ utype tmp = 0;
+ for (; it != end; ++it) {
+ const auto digit = _char_to_int(*it);
+ if (digit >= ubase) {
+ break;
+ }
+ if (SCN_UNLIKELY(tmp > cutoff ||
+ (tmp == cutoff && digit > cutlim))) {
+ if (!minus_sign) {
+ return error(error::value_out_of_range,
+ "Out of range: integer overflow");
+ }
+ return error(error::value_out_of_range,
+ "Out of range: integer underflow");
+ }
+ tmp = tmp * ubase + digit;
+ }
+ if (minus_sign) {
+ // special case: signed int minimum's absolute value can't
+ // be represented with the same type
+ //
+ // For example, short int -- range is [-32768, 32767], 32768
+ // can't be represented
+ //
+ // In that case, -static_cast<T>(tmp) would trigger UB
+ if (SCN_UNLIKELY(tmp == abs_int_min)) {
+ val = std::numeric_limits<T>::min();
+ }
+ else {
+ val = -static_cast<T>(tmp);
+ }
+ }
+ else {
+ val = static_cast<T>(tmp);
+ }
+ return it;
+
+ SCN_MSVC_POP
+ SCN_CLANG_POP
+ SCN_GCC_POP
+ }
+
+#if SCN_INCLUDE_SOURCE_DEFINITIONS
+
+#define SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(CharT, T) \
+ template expected<std::ptrdiff_t> integer_scanner<T>::_parse_int( \
+ T& val, span<const CharT> s); \
+ template expected<typename span<const CharT>::iterator> \
+ integer_scanner<T>::_parse_int_impl(T& val, bool minus_sign, \
+ span<const CharT> buf) const; \
+ template expected<typename span<const CharT>::iterator> \
+ integer_scanner<T>::parse_base_prefix(span<const CharT>, int&) const;
+
+#define SCN_DEFINE_INTEGER_SCANNER_MEMBERS(Char) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, signed char) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, short) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, int) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, long) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, long long) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, unsigned char) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, unsigned short) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, unsigned int) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, unsigned long) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, unsigned long long) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, char) \
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS_IMPL(Char, wchar_t)
+
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS(char)
+ SCN_DEFINE_INTEGER_SCANNER_MEMBERS(wchar_t)
+
+#endif
+
+ } // namespace detail
+
+ SCN_END_NAMESPACE
+} // namespace scn
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-24 18:48:20 +0000