tomlplusplus/include/toml++/impl/formatter.inl
2022-01-08 16:32:06 +02:00

514 lines
14 KiB
C++

//# This file is a part of toml++ and is subject to the the terms of the MIT license.
//# Copyright (c) Mark Gillard <mark.gillard@outlook.com.au>
//# See https://github.com/marzer/tomlplusplus/blob/master/LICENSE for the full license text.
// SPDX-License-Identifier: MIT
#pragma once
#include "preprocessor.h"
//# {{
#if !TOML_IMPLEMENTATION
#error This is an implementation-only header.
#endif
//# }}
#if TOML_ENABLE_FORMATTERS
#include "formatter.h"
#include "print_to_stream.h"
#include "value.h"
#include "table.h"
#include "array.h"
#include "unicode.h"
#include "parse_result.h"
#include "header_start.h"
TOML_IMPL_NAMESPACE_START
{
enum class TOML_CLOSED_FLAGS_ENUM formatted_string_traits : unsigned
{
none,
line_breaks = 1u << 0, // \n
tabs = 1u << 1, // \t
control_chars = 1u << 2, // also includes non-ascii vertical whitespace
single_quotes = 1u << 3,
non_bare = 1u << 4, // anything not satisfying "is bare key character"
non_ascii = 1u << 5, // any codepoint >= 128
all = (non_ascii << 1u) - 1u
};
TOML_MAKE_FLAGS(formatted_string_traits);
TOML_EXTERNAL_LINKAGE
formatter::formatter(const node* source_node,
const parse_result* source_pr,
const formatter_constants& constants,
const formatter_config& config) noexcept //
#if TOML_ENABLE_PARSER && !TOML_EXCEPTIONS
: source_{ source_pr && *source_pr ? &source_pr->table() : source_node },
result_{ source_pr },
#else
: source_{ source_pr ? source_pr : source_node },
#endif
constants_{ &constants },
config_{ config }
{
TOML_ASSERT_ASSUME(source_);
config_.flags = (config_.flags | constants_->mandatory_flags) & ~constants_->ignored_flags;
indent_columns_ = {};
for (auto c : config_.indent)
indent_columns_ += c == '\t' ? 4u : 1u;
int_format_mask_ = config_.flags
& (format_flags::allow_binary_integers | format_flags::allow_octal_integers
| format_flags::allow_hexadecimal_integers);
}
TOML_EXTERNAL_LINKAGE
void formatter::attach(std::ostream & stream) noexcept
{
indent_ = {};
naked_newline_ = true;
stream_ = &stream;
}
TOML_EXTERNAL_LINKAGE
void formatter::detach() noexcept
{
stream_ = nullptr;
}
TOML_EXTERNAL_LINKAGE
void formatter::print_newline(bool force)
{
if (!naked_newline_ || force)
{
print_to_stream(*stream_, '\n');
naked_newline_ = true;
}
}
TOML_EXTERNAL_LINKAGE
void formatter::print_indent()
{
for (int i = 0; i < indent_; i++)
{
print_to_stream(*stream_, config_.indent);
naked_newline_ = false;
}
}
TOML_EXTERNAL_LINKAGE
void formatter::print_unformatted(char c)
{
print_to_stream(*stream_, c);
naked_newline_ = false;
}
TOML_EXTERNAL_LINKAGE
void formatter::print_unformatted(std::string_view str)
{
print_to_stream(*stream_, str);
naked_newline_ = false;
}
TOML_EXTERNAL_LINKAGE
void formatter::print_string(std::string_view str, bool allow_multi_line, bool allow_bare)
{
if (str.empty())
{
print_unformatted(literal_strings_allowed() ? "''"sv : "\"\""sv);
return;
}
// pre-scan the string to determine how we should output it
formatted_string_traits traits = {};
if (!allow_bare)
traits |= formatted_string_traits::non_bare;
bool unicode_allowed = unicode_strings_allowed();
// ascii fast path
if (is_ascii(str.data(), str.length()))
{
for (auto c : str)
{
switch (c)
{
case '\n': traits |= formatted_string_traits::line_breaks; break;
case '\t': traits |= formatted_string_traits::tabs; break;
case '\'': traits |= formatted_string_traits::single_quotes; break;
default:
{
if TOML_UNLIKELY(is_control_character(c))
traits |= formatted_string_traits::control_chars;
if (!is_ascii_bare_key_character(static_cast<char32_t>(c)))
traits |= formatted_string_traits::non_bare;
break;
}
}
static constexpr auto all_ascii_traits =
formatted_string_traits::all & ~formatted_string_traits::non_ascii;
if (traits == all_ascii_traits)
break;
}
}
// unicode slow path
else
{
traits |= formatted_string_traits::non_ascii;
utf8_decoder decoder;
// if the unicode is malformed just treat the string as a single-line non-literal and
// escape all non-ascii characters (to ensure round-tripping and help with diagnostics)
const auto bad_unicode = [&]() noexcept
{
traits &= ~formatted_string_traits::line_breaks;
traits |= formatted_string_traits::control_chars | formatted_string_traits::non_bare;
unicode_allowed = false;
};
for (auto c : str)
{
decoder(c);
if TOML_UNLIKELY(decoder.error())
{
bad_unicode();
break;
}
if (!decoder.has_code_point())
continue;
switch (decoder.codepoint)
{
case U'\n': traits |= formatted_string_traits::line_breaks; break;
case U'\t': traits |= formatted_string_traits::tabs; break;
case U'\'': traits |= formatted_string_traits::single_quotes; break;
default:
{
if TOML_UNLIKELY(is_control_character(decoder.codepoint)
|| is_non_ascii_vertical_whitespace(decoder.codepoint))
traits |= formatted_string_traits::control_chars;
if (!is_bare_key_character(decoder.codepoint))
traits |= formatted_string_traits::non_bare;
break;
}
}
}
if (decoder.needs_more_input())
bad_unicode();
}
// if the string meets the requirements of being 'bare' we can emit a bare string
// (bare strings are composed of letters and numbers; no whitespace, control chars, quotes, etc)
if (!(traits & formatted_string_traits::non_bare)
&& (!(traits & formatted_string_traits::non_ascii) || unicode_allowed))
{
print_unformatted(str);
return;
}
// determine if this should be a multi-line string (triple-quotes)
const auto multi_line = allow_multi_line //
&& multi_line_strings_allowed() //
&& !!(traits & formatted_string_traits::line_breaks);
// determine if this should be a literal string (single-quotes with no escaping)
const auto literal = literal_strings_allowed() //
&& !(traits & formatted_string_traits::control_chars) //
&& (!(traits & formatted_string_traits::single_quotes) || multi_line) //
&& (!(traits & formatted_string_traits::tabs) || real_tabs_in_strings_allowed()) //
&& (!(traits & formatted_string_traits::non_ascii) || unicode_allowed);
// literal strings (single quotes, no escape codes)
if (literal)
{
const auto quot = multi_line ? R"(''')"sv : R"(')"sv;
print_unformatted(quot);
print_unformatted(str);
print_unformatted(quot);
return;
}
// anything from here down is a non-literal string, so requires iteration and escaping.
print_unformatted(multi_line ? R"(""")"sv : R"(")"sv);
const auto real_tabs_allowed = real_tabs_in_strings_allowed();
// ascii fast path
if (!(traits & formatted_string_traits::non_ascii))
{
for (auto c : str)
{
switch (c)
{
case '"': print_to_stream(*stream_, R"(\")"sv); break;
case '\\': print_to_stream(*stream_, R"(\\)"sv); break;
case '\x7F': print_to_stream(*stream_, R"(\u007F)"sv); break;
case '\t': print_to_stream(*stream_, real_tabs_allowed ? "\t"sv : R"(\t)"sv); break;
case '\n': print_to_stream(*stream_, multi_line ? "\n"sv : R"(\n)"sv); break;
default:
{
// control characters from lookup table
if TOML_UNLIKELY(c >= '\x00' && c <= '\x1F')
print_to_stream(*stream_, control_char_escapes[c]);
// regular characters
else
print_to_stream(*stream_, c);
}
}
}
}
// unicode slow path
else
{
utf8_decoder decoder;
const char* cp_start = str.data();
const char* cp_end = cp_start;
for (auto c : str)
{
decoder(c);
cp_end++;
// if the decoder encounters malformed unicode just emit raw bytes and
if (decoder.error())
{
while (cp_start != cp_end)
{
print_to_stream(*stream_, R"(\u00)"sv);
print_to_stream(*stream_,
static_cast<uint8_t>(*cp_start),
value_flags::format_as_hexadecimal,
2);
cp_start++;
}
decoder.reset();
continue;
}
if (!decoder.has_code_point())
continue;
switch (decoder.codepoint)
{
case U'"': print_to_stream(*stream_, R"(\")"sv); break;
case U'\\': print_to_stream(*stream_, R"(\\)"sv); break;
case U'\x7F': print_to_stream(*stream_, R"(\u007F)"sv); break;
case U'\t': print_to_stream(*stream_, real_tabs_allowed ? "\t"sv : R"(\t)"sv); break;
case U'\n': print_to_stream(*stream_, multi_line ? "\n"sv : R"(\n)"sv); break;
default:
{
// control characters from lookup table
if TOML_UNLIKELY(decoder.codepoint <= U'\x1F')
print_to_stream(*stream_,
control_char_escapes[static_cast<uint_least32_t>(decoder.codepoint)]);
// escaped unicode characters
else if (decoder.codepoint > U'\x7F'
&& (!unicode_allowed || is_non_ascii_vertical_whitespace(decoder.codepoint)))
{
if (static_cast<uint_least32_t>(decoder.codepoint) > 0xFFFFu)
{
print_to_stream(*stream_, R"(\U)"sv);
print_to_stream(*stream_,
static_cast<uint_least32_t>(decoder.codepoint),
value_flags::format_as_hexadecimal,
8);
}
else
{
print_to_stream(*stream_, R"(\u)"sv);
print_to_stream(*stream_,
static_cast<uint_least32_t>(decoder.codepoint),
value_flags::format_as_hexadecimal,
4);
}
}
// regular characters
else
print_to_stream(*stream_, cp_start, static_cast<size_t>(cp_end - cp_start));
}
}
cp_start = cp_end;
}
}
print_unformatted(multi_line ? R"(""")"sv : R"(")"sv);
}
TOML_EXTERNAL_LINKAGE
void formatter::print(const value<std::string>& val)
{
print_string(val.get());
}
TOML_EXTERNAL_LINKAGE
void formatter::print(const value<int64_t>& val)
{
naked_newline_ = false;
if (*val >= 0 && !!int_format_mask_)
{
static constexpr auto value_flags_mask =
value_flags::format_as_binary | value_flags::format_as_octal | value_flags::format_as_hexadecimal;
const auto fmt = val.flags() & value_flags_mask;
switch (fmt)
{
case value_flags::format_as_binary:
if (!!(int_format_mask_ & format_flags::allow_binary_integers))
{
print_to_stream(*stream_, "0b"sv);
print_to_stream(*stream_, *val, fmt);
return;
}
break;
case value_flags::format_as_octal:
if (!!(int_format_mask_ & format_flags::allow_octal_integers))
{
print_to_stream(*stream_, "0o"sv);
print_to_stream(*stream_, *val, fmt);
return;
}
break;
case value_flags::format_as_hexadecimal:
if (!!(int_format_mask_ & format_flags::allow_hexadecimal_integers))
{
print_to_stream(*stream_, "0x"sv);
print_to_stream(*stream_, *val, fmt);
return;
}
break;
default: break;
}
}
// fallback to decimal
print_to_stream(*stream_, *val);
}
TOML_EXTERNAL_LINKAGE
void formatter::print(const value<double>& val)
{
const std::string_view* inf_nan = nullptr;
switch (fpclassify(*val))
{
case fp_class::neg_inf: inf_nan = &constants_->float_neg_inf; break;
case fp_class::pos_inf: inf_nan = &constants_->float_pos_inf; break;
case fp_class::nan: inf_nan = &constants_->float_nan; break;
case fp_class::ok:
print_to_stream(*stream_,
*val,
value_flags::none,
!!(config_.flags & format_flags::relaxed_float_precision));
break;
default: TOML_UNREACHABLE;
}
if (inf_nan)
{
if (!!(config_.flags & format_flags::quote_infinities_and_nans))
print_to_stream_bookended(*stream_, *inf_nan, '"');
else
print_to_stream(*stream_, *inf_nan);
}
naked_newline_ = false;
}
TOML_EXTERNAL_LINKAGE
void formatter::print(const value<bool>& val)
{
print_unformatted(*val ? constants_->bool_true : constants_->bool_false);
}
TOML_EXTERNAL_LINKAGE
void formatter::print(const value<date>& val)
{
if (!!(config_.flags & format_flags::quote_dates_and_times))
print_to_stream_bookended(*stream_, *val, literal_strings_allowed() ? '\'' : '"');
else
print_to_stream(*stream_, *val);
naked_newline_ = false;
}
TOML_EXTERNAL_LINKAGE
void formatter::print(const value<time>& val)
{
if (!!(config_.flags & format_flags::quote_dates_and_times))
print_to_stream_bookended(*stream_, *val, literal_strings_allowed() ? '\'' : '"');
else
print_to_stream(*stream_, *val);
naked_newline_ = false;
}
TOML_EXTERNAL_LINKAGE
void formatter::print(const value<date_time>& val)
{
if (!!(config_.flags & format_flags::quote_dates_and_times))
print_to_stream_bookended(*stream_, *val, literal_strings_allowed() ? '\'' : '"');
else
print_to_stream(*stream_, *val);
naked_newline_ = false;
}
TOML_EXTERNAL_LINKAGE
void formatter::print_value(const node& val_node, node_type type)
{
TOML_ASSUME(type > node_type::array);
switch (type)
{
case node_type::string: print(*reinterpret_cast<const value<std::string>*>(&val_node)); break;
case node_type::integer: print(*reinterpret_cast<const value<int64_t>*>(&val_node)); break;
case node_type::floating_point: print(*reinterpret_cast<const value<double>*>(&val_node)); break;
case node_type::boolean: print(*reinterpret_cast<const value<bool>*>(&val_node)); break;
case node_type::date: print(*reinterpret_cast<const value<date>*>(&val_node)); break;
case node_type::time: print(*reinterpret_cast<const value<time>*>(&val_node)); break;
case node_type::date_time: print(*reinterpret_cast<const value<date_time>*>(&val_node)); break;
default: TOML_UNREACHABLE;
}
}
#if TOML_ENABLE_PARSER && !TOML_EXCEPTIONS
TOML_EXTERNAL_LINKAGE
bool formatter::dump_failed_parse_result()
{
if (result_ && !(*result_))
{
stream() << result_->error();
return true;
}
return false;
}
#else
TOML_EXTERNAL_LINKAGE
TOML_ATTR(const)
bool formatter::dump_failed_parse_result()
{
return false;
}
#endif
}
TOML_IMPL_NAMESPACE_END;
#include "header_end.h"
#endif // TOML_ENABLE_FORMATTERS