update_some instead update_s

README.md

@@ -127,7 +127,11 @@ int main() {
   mysql.replace(p);
   mysql.replace(v);
 
-  auto result = mysql.query<person>();  // vector<person>
+  // 更新指定字段
+  mysql.update_some<&person::name, &person::age>(p);
+  mysql.update_some<&person::name, &person::age>(v);
+
+  auto result = mysql.query_s<person>();
   for (auto &person : result) {
     std::cout << person.id << " " << person.name << " " << person.age
               << std::endl;

iguana/detail/fast_float.h

@@ -135,7 +135,6 @@ from_chars_result from_chars_advanced(const char* first, const char* last,
 #include <cstring>
 #include <type_traits>
 
-
 #if (defined(__x86_64) || defined(__x86_64__) || defined(_M_X64) ||       \
      defined(__amd64) || defined(__aarch64__) || defined(_M_ARM64) ||     \
      defined(__MINGW64__) || defined(__s390x__) ||                        \
@@ -2709,7 +2708,7 @@ fastfloat_really_inline void round(adjusted_mantissa& am,
   if (-am.power2 >= mantissa_shift) {
     // have a denormal float
     int32_t shift = -am.power2 + 1;
-    cb(am, std::min(shift, 64));
+    cb(am, (std::min)(shift, 64));
     // check for round-up: if rounding-nearest carried us to the hidden bit.
     am.power2 = (am.mantissa <
                  (uint64_t(1) << binary_format<T>::mantissa_explicit_bits()))

iguana/detail/pb_type.hpp

@@ -0,0 +1,135 @@
+#pragma once
+
+namespace iguana {
+
+struct sint32_t {
+  using value_type = int32_t;
+  int32_t val;
+  bool operator==(const sint32_t& other) const { return val == other.val; }
+};
+
+inline bool operator==(sint32_t value1, int32_t value2) {
+  return value1.val == value2;
+}
+
+// for key in std::map
+inline bool operator<(const sint32_t& lhs, const sint32_t& rhs) {
+  return lhs.val < rhs.val;
+}
+
+struct sint64_t {
+  using value_type = int64_t;
+  int64_t val;
+  bool operator==(const sint64_t& other) const { return val == other.val; }
+};
+
+inline bool operator==(sint64_t value1, int64_t value2) {
+  return value1.val == value2;
+}
+
+inline bool operator<(const sint64_t& lhs, const sint64_t& rhs) {
+  return lhs.val < rhs.val;
+}
+
+struct fixed32_t {
+  using value_type = uint32_t;
+  uint32_t val;
+  bool operator==(const fixed32_t& other) const { return val == other.val; }
+};
+
+inline bool operator==(fixed32_t value1, uint32_t value2) {
+  return value1.val == value2;
+}
+
+inline bool operator<(const fixed32_t& lhs, const fixed32_t& rhs) {
+  return lhs.val < rhs.val;
+}
+
+struct fixed64_t {
+  using value_type = uint64_t;
+  uint64_t val;
+  bool operator==(const fixed64_t& other) const { return val == other.val; }
+};
+
+inline bool operator==(fixed64_t value1, uint64_t value2) {
+  return value1.val == value2;
+}
+
+inline bool operator<(const fixed64_t& lhs, const fixed64_t& rhs) {
+  return lhs.val < rhs.val;
+}
+
+struct sfixed32_t {
+  using value_type = int32_t;
+  int32_t val;
+  bool operator==(const sfixed32_t& other) const { return val == other.val; }
+};
+
+inline bool operator==(sfixed32_t value1, int32_t value2) {
+  return value1.val == value2;
+}
+
+inline bool operator<(const sfixed32_t& lhs, const sfixed32_t& rhs) {
+  return lhs.val < rhs.val;
+}
+
+struct sfixed64_t {
+  using value_type = int64_t;
+  int64_t val;
+  bool operator==(const sfixed64_t& other) const { return val == other.val; }
+};
+
+inline bool operator==(sfixed64_t value1, int64_t value2) {
+  return value1.val == value2;
+}
+
+inline bool operator<(const sfixed64_t& lhs, const sfixed64_t& rhs) {
+  return lhs.val < rhs.val;
+}
+
+}  // namespace iguana
+
+// for key in std::unordered_map
+namespace std {
+template <>
+struct hash<iguana::sint32_t> {
+  size_t operator()(const iguana::sint32_t& x) const noexcept {
+    return std::hash<int32_t>()(x.val);
+  }
+};
+
+template <>
+struct hash<iguana::sint64_t> {
+  size_t operator()(const iguana::sint64_t& x) const noexcept {
+    return std::hash<int64_t>()(x.val);
+  }
+};
+
+template <>
+struct hash<iguana::fixed32_t> {
+  size_t operator()(const iguana::fixed32_t& x) const noexcept {
+    return std::hash<uint32_t>()(x.val);
+  }
+};
+
+template <>
+struct hash<iguana::fixed64_t> {
+  size_t operator()(const iguana::fixed64_t& x) const noexcept {
+    return std::hash<uint64_t>()(x.val);
+  }
+};
+
+template <>
+struct hash<iguana::sfixed32_t> {
+  size_t operator()(const iguana::sfixed32_t& x) const noexcept {
+    return std::hash<int32_t>()(x.val);
+  }
+};
+
+template <>
+struct hash<iguana::sfixed64_t> {
+  size_t operator()(const iguana::sfixed64_t& x) const noexcept {
+    return std::hash<int64_t>()(x.val);
+  }
+};
+}  // namespace std

iguana/detail/string_resize.hpp

@@ -0,0 +1,131 @@
+#pragma once
+#include <cstddef>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace iguana::detail {
+
+#if __cpp_lib_string_resize_and_overwrite >= 202110L
+template <typename ch>
+inline void resize(std::basic_string<ch> &str, std::size_t sz) {
+  str.resize_and_overwrite(sz, [sz](ch *, std::size_t) {
+    return sz;
+  });
+}
+#elif (defined(_MSC_VER) && _MSC_VER <= 1920)
+// old msvc don't support visit private, discard it.
+
+#else
+
+template <typename Function, Function func_ptr>
+class string_thief {
+ public:
+  friend void string_set_length_hacker(std::string &self, std::size_t sz) {
+#if defined(_MSVC_STL_VERSION)
+    (self.*func_ptr)._Myval2._Mysize = sz;
+#else
+#if defined(_LIBCPP_VERSION)
+    (self.*func_ptr)(sz);
+#else
+#if (_GLIBCXX_USE_CXX11_ABI == 0) && defined(__GLIBCXX__)
+    (self.*func_ptr)()->_M_set_length_and_sharable(sz);
+#else
+#if defined(__GLIBCXX__)
+    (self.*func_ptr)(sz);
+#endif
+#endif
+#endif
+#endif
+  }
+};
+
+#if defined(__GLIBCXX__)  // libstdc++
+#if (_GLIBCXX_USE_CXX11_ABI == 0)
+template class string_thief<decltype(&std::string::_M_rep),
+                            &std::string::_M_rep>;
+#else
+template class string_thief<decltype(&std::string::_M_set_length),
+                            &std::string::_M_set_length>;
+#endif
+#elif defined(_LIBCPP_VERSION)
+template class string_thief<decltype(&std::string::__set_size),
+                            &std::string::__set_size>;
+#elif defined(_MSVC_STL_VERSION)
+template class string_thief<decltype(&std::string::_Mypair),
+                            &std::string::_Mypair>;
+#endif
+
+void string_set_length_hacker(std::string &, std::size_t);
+
+template <typename ch>
+inline void resize(std::basic_string<ch> &raw_str, std::size_t sz) {
+  std::string &str = *reinterpret_cast<std::string *>(&raw_str);
+#if defined(__GLIBCXX__) || defined(_LIBCPP_VERSION) || \
+    defined(_MSVC_STL_VERSION)
+  if (sz > str.capacity()) {
+    str.reserve(sz);
+  }
+  string_set_length_hacker(str, sz);
+  str[sz] = '\0';
+#else
+  raw_str.resize(sz);
+#endif
+}
+
+#endif
+
+#if (defined(_MSC_VER) && _MSC_VER <= 1920)
+#else
+void vector_set_length_hacker(std::vector<char> &self, std::size_t sz);
+
+template <typename Function, Function func_ptr>
+class vector_thief {
+ public:
+  friend void vector_set_length_hacker(std::vector<char> &self,
+                                       std::size_t sz) {
+#if defined(_MSVC_STL_VERSION)
+    (self.*func_ptr)._Myval2._Mylast = self.data() + sz;
+#else
+#if defined(_LIBCPP_VERSION)
+#if _LIBCPP_VERSION < 14000
+    ((*(std::__vector_base<char, std::allocator<char> > *)(&self)).*func_ptr) =
+        self.data() + sz;
+#else
+    (self.*func_ptr) = self.data() + sz;
+#endif
+#else
+#if defined(__GLIBCXX__)
+    ((*(std::_Vector_base<char, std::allocator<char> > *)(&self)).*func_ptr)
+        ._M_finish = self.data() + sz;
+#endif
+#endif
+#endif
+  }
+};
+
+#if defined(__GLIBCXX__)  // libstdc++
+template class vector_thief<decltype(&std::vector<char>::_M_impl),
+                            &std::vector<char>::_M_impl>;
+#elif defined(_LIBCPP_VERSION)
+template class vector_thief<decltype(&std::vector<char>::__end_),
+                            &std::vector<char>::__end_>;
+#elif defined(_MSVC_STL_VERSION)
+template class vector_thief<decltype(&std::vector<char>::_Mypair),
+                            &std::vector<char>::_Mypair>;
+#endif
+
+template <typename ch>
+inline void resize(std::vector<ch> &raw_vec, std::size_t sz) {
+#if defined(__GLIBCXX__) ||                                       \
+    (defined(_LIBCPP_VERSION) && defined(_LIBCPP_HAS_NO_ASAN)) || \
+    defined(_MSVC_STL_VERSION)
+  std::vector<char> &vec = *reinterpret_cast<std::vector<char> *>(&raw_vec);
+  vec.reserve(sz);
+  vector_set_length_hacker(vec, sz);
+#else
+  raw_vec.resize(sz);
+#endif
+}
+#endif
+};  // namespace iguana::detail

iguana/detail/traits.hpp

@@ -79,5 +79,39 @@ struct member_tratis<T Owner::*> {
 template <typename T>
 inline constexpr bool is_int64_v =
     std::is_same_v<T, int64_t> || std::is_same_v<T, uint64_t>;
+
+template <typename T>
+struct is_variant : std::false_type {};
+
+template <typename... T>
+struct is_variant<std::variant<T...>> : std::true_type {};
+
+template <class T>
+struct member_traits {
+  using value_type = T;
+};
+
+template <class T, class Owner>
+struct member_traits<T Owner::*> {
+  using owner_type = Owner;
+  using value_type = T;
+};
+
+template <class T>
+using member_value_type_t = typename member_traits<T>::value_type;
+
+template <typename T, std::size_t I, typename = void>
+struct variant_type_at {
+  using type = T;
+};
+
+template <typename T, std::size_t I>
+struct variant_type_at<T, I, std::enable_if_t<is_variant<T>::value>> {
+  using type = std::variant_alternative_t<I, T>;
+};
+template <typename T, std::size_t I>
+using variant_type_at_t =
+    typename variant_type_at<typename member_traits<T>::value_type, I>::type;
+
 }  // namespace iguana
 #endif  // SERIALIZE_TRAITS_HPP