diff options
Diffstat (limited to 'absl/strings/internal/str_format/extension.h')
| -rw-r--r-- | absl/strings/internal/str_format/extension.h | 277 |
1 files changed, 202 insertions, 75 deletions
diff --git a/absl/strings/internal/str_format/extension.h b/absl/strings/internal/str_format/extension.h index fb31a9db415e..f0cffe1e6d6c 100644 --- a/absl/strings/internal/str_format/extension.h +++ b/absl/strings/internal/str_format/extension.h @@ -30,7 +30,10 @@ namespace absl { ABSL_NAMESPACE_BEGIN + namespace str_format_internal { +enum class FormatConversionCharSet : uint64_t; +enum class FormatConversionChar : uint8_t; class FormatRawSinkImpl { public: @@ -149,13 +152,39 @@ struct Flags { X_VAL(g) X_SEP X_VAL(G) X_SEP X_VAL(a) X_SEP X_VAL(A) X_SEP \ /* misc */ \ X_VAL(n) X_SEP X_VAL(p) +// clang-format on -enum class FormatConversionChar : uint8_t { +// This type should not be referenced, it exists only to provide labels +// internally that match the values declared in FormatConversionChar in +// str_format.h. This is meant to allow internal libraries to use the same +// declared interface type as the public interface +// (absl::StrFormatConversionChar) while keeping the definition in a public +// header. +// Internal libraries should use the form +// `FormatConversionCharInternal::c`, `FormatConversionCharInternal::kNone` for +// comparisons. Use in switch statements is not recommended due to a bug in how +// gcc 4.9 -Wswitch handles declared but undefined enums. +struct FormatConversionCharInternal { + FormatConversionCharInternal() = delete; + + private: + // clang-format off + enum class Enum : uint8_t { c, C, s, S, // text d, i, o, u, x, X, // int f, F, e, E, g, G, a, A, // float n, p, // misc kNone + }; + // clang-format on + public: +#define ABSL_INTERNAL_X_VAL(id) \ + static constexpr FormatConversionChar id = \ + static_cast<FormatConversionChar>(Enum::id); + ABSL_INTERNAL_CONVERSION_CHARS_EXPAND_(ABSL_INTERNAL_X_VAL, ) +#undef ABSL_INTERNAL_X_VAL + static constexpr FormatConversionChar kNone = + static_cast<FormatConversionChar>(Enum::kNone); }; // clang-format on @@ -163,56 +192,56 @@ inline FormatConversionChar FormatConversionCharFromChar(char c) { switch (c) { #define ABSL_INTERNAL_X_VAL(id) \ case #id[0]: \ - return FormatConversionChar::id; + return FormatConversionCharInternal::id; ABSL_INTERNAL_CONVERSION_CHARS_EXPAND_(ABSL_INTERNAL_X_VAL, ) #undef ABSL_INTERNAL_X_VAL } - return FormatConversionChar::kNone; + return FormatConversionCharInternal::kNone; } inline bool FormatConversionCharIsUpper(FormatConversionChar c) { - switch (c) { - case FormatConversionChar::X: - case FormatConversionChar::F: - case FormatConversionChar::E: - case FormatConversionChar::G: - case FormatConversionChar::A: - return true; - default: - return false; + if (c == FormatConversionCharInternal::X || + c == FormatConversionCharInternal::F || + c == FormatConversionCharInternal::E || + c == FormatConversionCharInternal::G || + c == FormatConversionCharInternal::A) { + return true; + } else { + return false; } } inline bool FormatConversionCharIsFloat(FormatConversionChar c) { - switch (c) { - case FormatConversionChar::a: - case FormatConversionChar::e: - case FormatConversionChar::f: - case FormatConversionChar::g: - case FormatConversionChar::A: - case FormatConversionChar::E: - case FormatConversionChar::F: - case FormatConversionChar::G: - return true; - default: - return false; + if (c == FormatConversionCharInternal::a || + c == FormatConversionCharInternal::e || + c == FormatConversionCharInternal::f || + c == FormatConversionCharInternal::g || + c == FormatConversionCharInternal::A || + c == FormatConversionCharInternal::E || + c == FormatConversionCharInternal::F || + c == FormatConversionCharInternal::G) { + return true; + } else { + return false; } } inline char FormatConversionCharToChar(FormatConversionChar c) { - switch (c) { -#define ABSL_INTERNAL_X_VAL(e) \ - case FormatConversionChar::e: \ + if (c == FormatConversionCharInternal::kNone) { + return '\0'; + +#define ABSL_INTERNAL_X_VAL(e) \ + } else if (c == FormatConversionCharInternal::e) { \ return #e[0]; #define ABSL_INTERNAL_X_SEP - ABSL_INTERNAL_CONVERSION_CHARS_EXPAND_(ABSL_INTERNAL_X_VAL, - ABSL_INTERNAL_X_SEP) - case FormatConversionChar::kNone: - return '\0'; + ABSL_INTERNAL_CONVERSION_CHARS_EXPAND_(ABSL_INTERNAL_X_VAL, + ABSL_INTERNAL_X_SEP) + } else { + return '\0'; + } + #undef ABSL_INTERNAL_X_VAL #undef ABSL_INTERNAL_X_SEP - } - return '\0'; } // The associated char. @@ -224,7 +253,7 @@ inline std::ostream& operator<<(std::ostream& os, FormatConversionChar v) { struct FormatConversionSpecImplFriend; -class FormatConversionSpec { +class FormatConversionSpecImpl { public: // Width and precison are not specified, no flags are set. bool is_basic() const { return flags_.basic; } @@ -237,7 +266,7 @@ class FormatConversionSpec { FormatConversionChar conversion_char() const { // Keep this field first in the struct . It generates better code when // accessing it when ConversionSpec is passed by value in registers. - static_assert(offsetof(FormatConversionSpec, conv_) == 0, ""); + static_assert(offsetof(FormatConversionSpecImpl, conv_) == 0, ""); return conv_; } @@ -248,37 +277,62 @@ class FormatConversionSpec { // negative value. int precision() const { return precision_; } + template <typename T> + T Wrap() { + return T(*this); + } + private: friend struct str_format_internal::FormatConversionSpecImplFriend; - FormatConversionChar conv_ = FormatConversionChar::kNone; + FormatConversionChar conv_ = FormatConversionCharInternal::kNone; Flags flags_; int width_; int precision_; }; struct FormatConversionSpecImplFriend final { - static void SetFlags(Flags f, FormatConversionSpec* conv) { + static void SetFlags(Flags f, FormatConversionSpecImpl* conv) { conv->flags_ = f; } static void SetConversionChar(FormatConversionChar c, - FormatConversionSpec* conv) { + FormatConversionSpecImpl* conv) { conv->conv_ = c; } - static void SetWidth(int w, FormatConversionSpec* conv) { conv->width_ = w; } - static void SetPrecision(int p, FormatConversionSpec* conv) { + static void SetWidth(int w, FormatConversionSpecImpl* conv) { + conv->width_ = w; + } + static void SetPrecision(int p, FormatConversionSpecImpl* conv) { conv->precision_ = p; } - static std::string FlagsToString(const FormatConversionSpec& spec) { + static std::string FlagsToString(const FormatConversionSpecImpl& spec) { return spec.flags_.ToString(); } }; -constexpr uint64_t FormatConversionCharToConvValue(char conv) { +// Type safe OR operator. +// We need this for two reasons: +// 1. operator| on enums makes them decay to integers and the result is an +// integer. We need the result to stay as an enum. +// 2. We use "enum class" which would not work even if we accepted the decay. +constexpr FormatConversionCharSet FormatConversionCharSetUnion( + FormatConversionCharSet a) { + return a; +} + +template <typename... CharSet> +constexpr FormatConversionCharSet FormatConversionCharSetUnion( + FormatConversionCharSet a, CharSet... rest) { + return static_cast<FormatConversionCharSet>( + static_cast<uint64_t>(a) | + static_cast<uint64_t>(FormatConversionCharSetUnion(rest...))); +} + +constexpr uint64_t FormatConversionCharToConvInt(char conv) { return -#define ABSL_INTERNAL_CHAR_SET_CASE(c) \ - conv == #c[0] \ - ? (uint64_t{1} << (1 + static_cast<uint8_t>(FormatConversionChar::c))) \ - : +#define ABSL_INTERNAL_CHAR_SET_CASE(c) \ + conv == #c[0] ? (uint64_t{1} << (1 + static_cast<uint8_t>( \ + FormatConversionCharInternal::c))) \ + : ABSL_INTERNAL_CONVERSION_CHARS_EXPAND_(ABSL_INTERNAL_CHAR_SET_CASE, ) #undef ABSL_INTERNAL_CHAR_SET_CASE conv == '*' @@ -286,20 +340,31 @@ constexpr uint64_t FormatConversionCharToConvValue(char conv) { : 0; } -enum class FormatConversionCharSet : uint64_t { -#define ABSL_INTERNAL_CHAR_SET_CASE(c) \ - c = FormatConversionCharToConvValue(#c[0]), +constexpr FormatConversionCharSet FormatConversionCharToConvValue(char conv) { + return static_cast<FormatConversionCharSet>( + FormatConversionCharToConvInt(conv)); +} + +struct FormatConversionCharSetInternal { +#define ABSL_INTERNAL_CHAR_SET_CASE(c) \ + static constexpr FormatConversionCharSet c = \ + FormatConversionCharToConvValue(#c[0]); ABSL_INTERNAL_CONVERSION_CHARS_EXPAND_(ABSL_INTERNAL_CHAR_SET_CASE, ) #undef ABSL_INTERNAL_CHAR_SET_CASE // Used for width/precision '*' specification. - kStar = FormatConversionCharToConvValue('*'), - // Some predefined values: - kIntegral = d | i | u | o | x | X, - kFloating = a | e | f | g | A | E | F | G, - kNumeric = kIntegral | kFloating, - kString = s, - kPointer = p + static constexpr FormatConversionCharSet kStar = + FormatConversionCharToConvValue('*'); + + // Some predefined values (TODO(matthewbr), delete any that are unused). + static constexpr FormatConversionCharSet kIntegral = + FormatConversionCharSetUnion(d, i, u, o, x, X); + static constexpr FormatConversionCharSet kFloating = + FormatConversionCharSetUnion(a, e, f, g, A, E, F, G); + static constexpr FormatConversionCharSet kNumeric = + FormatConversionCharSetUnion(kIntegral, kFloating); + static constexpr FormatConversionCharSet kString = s; + static constexpr FormatConversionCharSet kPointer = p; }; // Type safe OR operator. @@ -309,8 +374,7 @@ enum class FormatConversionCharSet : uint64_t { // 2. We use "enum class" which would not work even if we accepted the decay. constexpr FormatConversionCharSet operator|(FormatConversionCharSet a, FormatConversionCharSet b) { - return FormatConversionCharSet(static_cast<uint64_t>(a) | - static_cast<uint64_t>(b)); + return FormatConversionCharSetUnion(a, b); } // Overloaded conversion functions to support absl::ParsedFormat. @@ -331,7 +395,8 @@ void ToFormatConversionCharSet(T) = delete; // Checks whether `c` exists in `set`. constexpr bool Contains(FormatConversionCharSet set, char c) { - return (static_cast<uint64_t>(set) & FormatConversionCharToConvValue(c)) != 0; + return (static_cast<uint64_t>(set) & + static_cast<uint64_t>(FormatConversionCharToConvValue(c))) != 0; } // Checks whether all the characters in `c` are contained in `set` @@ -341,19 +406,6 @@ constexpr bool Contains(FormatConversionCharSet set, static_cast<uint64_t>(c); } -// Return type of the AbslFormatConvert() functions. -// The FormatConversionCharSet template parameter is used to inform the -// framework of what conversion characters are supported by that -// AbslFormatConvert routine. -template <FormatConversionCharSet C> -struct FormatConvertResult { - static constexpr FormatConversionCharSet kConv = C; - bool value; -}; - -template <FormatConversionCharSet C> -constexpr FormatConversionCharSet FormatConvertResult<C>::kConv; - // Return capacity - used, clipped to a minimum of 0. inline size_t Excess(size_t used, size_t capacity) { return used < capacity ? capacity - used : 0; @@ -361,10 +413,85 @@ inline size_t Excess(size_t used, size_t capacity) { // Type alias for use during migration. using ConversionChar = FormatConversionChar; -using ConversionSpec = FormatConversionSpec; +using ConversionSpec = FormatConversionSpecImpl; using Conv = FormatConversionCharSet; -template <FormatConversionCharSet C> -using ConvertResult = FormatConvertResult<C>; + +class FormatConversionSpec { + public: + // Width and precison are not specified, no flags are set. + bool is_basic() const { return impl_.is_basic(); } + bool has_left_flag() const { return impl_.has_left_flag(); } + bool has_show_pos_flag() const { return impl_.has_show_pos_flag(); } + bool has_sign_col_flag() const { return impl_.has_sign_col_flag(); } + bool has_alt_flag() const { return impl_.has_alt_flag(); } + bool has_zero_flag() const { return impl_.has_zero_flag(); } + + FormatConversionChar conversion_char() const { + return impl_.conversion_char(); + } + + // Returns the specified width. If width is unspecfied, it returns a negative + // value. + int width() const { return impl_.width(); } + // Returns the specified precision. If precision is unspecfied, it returns a + // negative value. + int precision() const { return impl_.precision(); } + + private: + explicit FormatConversionSpec( + str_format_internal::FormatConversionSpecImpl impl) + : impl_(impl) {} + + friend str_format_internal::FormatConversionSpecImpl; + + absl::str_format_internal::FormatConversionSpecImpl impl_; +}; + +// clang-format off +enum class FormatConversionChar : uint8_t { + c, C, s, S, // text + d, i, o, u, x, X, // int + f, F, e, E, g, G, a, A, // float + n, p // misc +}; +// clang-format on + +enum class FormatConversionCharSet : uint64_t { + // text + c = str_format_internal::FormatConversionCharToConvInt('c'), + C = str_format_internal::FormatConversionCharToConvInt('C'), + s = str_format_internal::FormatConversionCharToConvInt('s'), + S = str_format_internal::FormatConversionCharToConvInt('S'), + // integer + d = str_format_internal::FormatConversionCharToConvInt('d'), + i = str_format_internal::FormatConversionCharToConvInt('i'), + o = str_format_internal::FormatConversionCharToConvInt('o'), + u = str_format_internal::FormatConversionCharToConvInt('u'), + x = str_format_internal::FormatConversionCharToConvInt('x'), + X = str_format_internal::FormatConversionCharToConvInt('X'), + // Float + f = str_format_internal::FormatConversionCharToConvInt('f'), + F = str_format_internal::FormatConversionCharToConvInt('F'), + e = str_format_internal::FormatConversionCharToConvInt('e'), + E = str_format_internal::FormatConversionCharToConvInt('E'), + g = str_format_internal::FormatConversionCharToConvInt('g'), + G = str_format_internal::FormatConversionCharToConvInt('G'), + a = str_format_internal::FormatConversionCharToConvInt('a'), + A = str_format_internal::FormatConversionCharToConvInt('A'), + // misc + n = str_format_internal::FormatConversionCharToConvInt('n'), + p = str_format_internal::FormatConversionCharToConvInt('p'), + + // Used for width/precision '*' specification. + kStar = str_format_internal::FormatConversionCharToConvInt('*'), + + // Some predefined values: + kIntegral = d | i | u | o | x | X, + kFloating = a | e | f | g | A | E | F | G, + kNumeric = kIntegral | kFloating, + kString = s, + kPointer = p, +}; } // namespace str_format_internal |