serenity/AK/Format.cpp
Ali Mohammad Pur 73cb566041 AK: Make vout() log to debug instead of VERIFY()'ing
In case the write was to stderr/stdout, and it just so happened to fail
because of an issue like "the pty is gone", VERIFY() would end up
calling vout() back to write to stderr, which would then fail forever
until the stack is exhausted.
"Fixes" the issue where the Shell would crash in horrible ways when the
terminal is closed.
2021-05-19 09:19:29 +02:00

721 lines
21 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Format.h>
#include <AK/GenericLexer.h>
#include <AK/String.h>
#include <AK/StringBuilder.h>
#include <AK/kstdio.h>
#include <ctype.h>
#if defined(__serenity__) && !defined(KERNEL)
# include <serenity.h>
#endif
#ifdef KERNEL
# include <Kernel/Process.h>
# include <Kernel/Thread.h>
#else
# include <stdio.h>
# include <string.h>
#endif
namespace AK {
namespace {
static constexpr size_t use_next_index = NumericLimits<size_t>::max();
// The worst case is that we have the largest 64-bit value formatted as binary number, this would take
// 65 bytes. Choosing a larger power of two won't hurt and is a bit of mitigation against out-of-bounds accesses.
static constexpr size_t convert_unsigned_to_string(u64 value, Array<u8, 128>& buffer, u8 base, bool upper_case)
{
VERIFY(base >= 2 && base <= 16);
constexpr const char* lowercase_lookup = "0123456789abcdef";
constexpr const char* uppercase_lookup = "0123456789ABCDEF";
if (value == 0) {
buffer[0] = '0';
return 1;
}
size_t used = 0;
while (value > 0) {
if (upper_case)
buffer[used++] = uppercase_lookup[value % base];
else
buffer[used++] = lowercase_lookup[value % base];
value /= base;
}
for (size_t i = 0; i < used / 2; ++i)
swap(buffer[i], buffer[used - i - 1]);
return used;
}
void vformat_impl(TypeErasedFormatParams& params, FormatBuilder& builder, FormatParser& parser)
{
const auto literal = parser.consume_literal();
builder.put_literal(literal);
FormatParser::FormatSpecifier specifier;
if (!parser.consume_specifier(specifier)) {
VERIFY(parser.is_eof());
return;
}
if (specifier.index == use_next_index)
specifier.index = params.take_next_index();
auto& parameter = params.parameters().at(specifier.index);
FormatParser argparser { specifier.flags };
parameter.formatter(params, builder, argparser, parameter.value);
vformat_impl(params, builder, parser);
}
} // namespace AK::{anonymous}
FormatParser::FormatParser(StringView input)
: GenericLexer(input)
{
}
StringView FormatParser::consume_literal()
{
const auto begin = tell();
while (!is_eof()) {
if (consume_specific("{{"))
continue;
if (consume_specific("}}"))
continue;
if (next_is(is_any_of("{}")))
return m_input.substring_view(begin, tell() - begin);
consume();
}
return m_input.substring_view(begin);
}
bool FormatParser::consume_number(size_t& value)
{
value = 0;
bool consumed_at_least_one = false;
while (next_is(isdigit)) {
value *= 10;
value += consume() - '0';
consumed_at_least_one = true;
}
return consumed_at_least_one;
}
bool FormatParser::consume_specifier(FormatSpecifier& specifier)
{
VERIFY(!next_is('}'));
if (!consume_specific('{'))
return false;
if (!consume_number(specifier.index))
specifier.index = use_next_index;
if (consume_specific(':')) {
const auto begin = tell();
size_t level = 1;
while (level > 0) {
VERIFY(!is_eof());
if (consume_specific('{')) {
++level;
continue;
}
if (consume_specific('}')) {
--level;
continue;
}
consume();
}
specifier.flags = m_input.substring_view(begin, tell() - begin - 1);
} else {
if (!consume_specific('}'))
VERIFY_NOT_REACHED();
specifier.flags = "";
}
return true;
}
bool FormatParser::consume_replacement_field(size_t& index)
{
if (!consume_specific('{'))
return false;
if (!consume_number(index))
index = use_next_index;
if (!consume_specific('}'))
VERIFY_NOT_REACHED();
return true;
}
void FormatBuilder::put_padding(char fill, size_t amount)
{
for (size_t i = 0; i < amount; ++i)
m_builder.append(fill);
}
void FormatBuilder::put_literal(StringView value)
{
for (size_t i = 0; i < value.length(); ++i) {
m_builder.append(value[i]);
if (value[i] == '{' || value[i] == '}')
++i;
}
}
void FormatBuilder::put_string(
StringView value,
Align align,
size_t min_width,
size_t max_width,
char fill)
{
const auto used_by_string = min(max_width, value.length());
const auto used_by_padding = max(min_width, used_by_string) - used_by_string;
if (used_by_string < value.length())
value = value.substring_view(0, used_by_string);
if (align == Align::Left || align == Align::Default) {
m_builder.append(value);
put_padding(fill, used_by_padding);
} else if (align == Align::Center) {
const auto used_by_left_padding = used_by_padding / 2;
const auto used_by_right_padding = ceil_div<size_t, size_t>(used_by_padding, 2);
put_padding(fill, used_by_left_padding);
m_builder.append(value);
put_padding(fill, used_by_right_padding);
} else if (align == Align::Right) {
put_padding(fill, used_by_padding);
m_builder.append(value);
}
}
void FormatBuilder::put_u64(
u64 value,
u8 base,
bool prefix,
bool upper_case,
bool zero_pad,
Align align,
size_t min_width,
char fill,
SignMode sign_mode,
bool is_negative)
{
if (align == Align::Default)
align = Align::Right;
Array<u8, 128> buffer;
const auto used_by_digits = convert_unsigned_to_string(value, buffer, base, upper_case);
size_t used_by_prefix = 0;
if (align == Align::Right && zero_pad) {
// We want String::formatted("{:#08x}", 32) to produce '0x00000020' instead of '0x000020'. This
// behaviour differs from both fmtlib and printf, but is more intuitive.
used_by_prefix = 0;
} else {
if (is_negative || sign_mode != SignMode::OnlyIfNeeded)
used_by_prefix += 1;
if (prefix) {
if (base == 8)
used_by_prefix += 1;
else if (base == 16)
used_by_prefix += 2;
else if (base == 2)
used_by_prefix += 2;
}
}
const auto used_by_field = used_by_prefix + used_by_digits;
const auto used_by_padding = max(used_by_field, min_width) - used_by_field;
const auto put_prefix = [&]() {
if (is_negative)
m_builder.append('-');
else if (sign_mode == SignMode::Always)
m_builder.append('+');
else if (sign_mode == SignMode::Reserved)
m_builder.append(' ');
if (prefix) {
if (base == 2) {
if (upper_case)
m_builder.append("0B");
else
m_builder.append("0b");
} else if (base == 8) {
m_builder.append("0");
} else if (base == 16) {
if (upper_case)
m_builder.append("0X");
else
m_builder.append("0x");
}
}
};
const auto put_digits = [&]() {
for (size_t i = 0; i < used_by_digits; ++i)
m_builder.append(buffer[i]);
};
if (align == Align::Left) {
const auto used_by_right_padding = used_by_padding;
put_prefix();
put_digits();
put_padding(fill, used_by_right_padding);
} else if (align == Align::Center) {
const auto used_by_left_padding = used_by_padding / 2;
const auto used_by_right_padding = ceil_div<size_t, size_t>(used_by_padding, 2);
put_padding(fill, used_by_left_padding);
put_prefix();
put_digits();
put_padding(fill, used_by_right_padding);
} else if (align == Align::Right) {
const auto used_by_left_padding = used_by_padding;
if (zero_pad) {
put_prefix();
put_padding('0', used_by_left_padding);
put_digits();
} else {
put_padding(fill, used_by_left_padding);
put_prefix();
put_digits();
}
}
}
void FormatBuilder::put_i64(
i64 value,
u8 base,
bool prefix,
bool upper_case,
bool zero_pad,
Align align,
size_t min_width,
char fill,
SignMode sign_mode)
{
const auto is_negative = value < 0;
value = is_negative ? -value : value;
put_u64(static_cast<u64>(value), base, prefix, upper_case, zero_pad, align, min_width, fill, sign_mode, is_negative);
}
#ifndef KERNEL
void FormatBuilder::put_f64(
double value,
u8 base,
bool upper_case,
Align align,
size_t min_width,
size_t precision,
char fill,
SignMode sign_mode)
{
StringBuilder string_builder;
FormatBuilder format_builder { string_builder };
bool is_negative = value < 0.0;
if (is_negative)
value = -value;
format_builder.put_u64(static_cast<u64>(value), base, false, upper_case, false, Align::Right, 0, ' ', sign_mode, is_negative);
if (precision > 0) {
// FIXME: This is a terrible approximation but doing it properly would be a lot of work. If someone is up for that, a good
// place to start would be the following video from CppCon 2019:
// https://youtu.be/4P_kbF0EbZM (Stephan T. Lavavej “Floating-Point <charconv>: Making Your Code 10x Faster With C++17's Final Boss”)
value -= static_cast<i64>(value);
double epsilon = 0.5;
for (size_t i = 0; i < precision; ++i)
epsilon /= 10.0;
size_t visible_precision = 0;
for (; visible_precision < precision; ++visible_precision) {
if (value - static_cast<i64>(value) < epsilon)
break;
value *= 10.0;
epsilon *= 10.0;
}
if (visible_precision > 0) {
string_builder.append('.');
format_builder.put_u64(static_cast<u64>(value), base, false, upper_case, true, Align::Right, visible_precision);
}
}
put_string(string_builder.string_view(), align, min_width, NumericLimits<size_t>::max(), fill);
}
#endif
void vformat(StringBuilder& builder, StringView fmtstr, TypeErasedFormatParams params)
{
FormatBuilder fmtbuilder { builder };
FormatParser parser { fmtstr };
vformat_impl(params, fmtbuilder, parser);
}
void StandardFormatter::parse(TypeErasedFormatParams& params, FormatParser& parser)
{
if (StringView { "<^>" }.contains(parser.peek(1))) {
VERIFY(!parser.next_is(is_any_of("{}")));
m_fill = parser.consume();
}
if (parser.consume_specific('<'))
m_align = FormatBuilder::Align::Left;
else if (parser.consume_specific('^'))
m_align = FormatBuilder::Align::Center;
else if (parser.consume_specific('>'))
m_align = FormatBuilder::Align::Right;
if (parser.consume_specific('-'))
m_sign_mode = FormatBuilder::SignMode::OnlyIfNeeded;
else if (parser.consume_specific('+'))
m_sign_mode = FormatBuilder::SignMode::Always;
else if (parser.consume_specific(' '))
m_sign_mode = FormatBuilder::SignMode::Reserved;
if (parser.consume_specific('#'))
m_alternative_form = true;
if (parser.consume_specific('0'))
m_zero_pad = true;
if (size_t index = 0; parser.consume_replacement_field(index)) {
if (index == use_next_index)
index = params.take_next_index();
m_width = params.parameters().at(index).to_size();
} else if (size_t width = 0; parser.consume_number(width)) {
m_width = width;
}
if (parser.consume_specific('.')) {
if (size_t index = 0; parser.consume_replacement_field(index)) {
if (index == use_next_index)
index = params.take_next_index();
m_precision = params.parameters().at(index).to_size();
} else if (size_t precision = 0; parser.consume_number(precision)) {
m_precision = precision;
}
}
if (parser.consume_specific('b'))
m_mode = Mode::Binary;
else if (parser.consume_specific('B'))
m_mode = Mode::BinaryUppercase;
else if (parser.consume_specific('d'))
m_mode = Mode::Decimal;
else if (parser.consume_specific('o'))
m_mode = Mode::Octal;
else if (parser.consume_specific('x'))
m_mode = Mode::Hexadecimal;
else if (parser.consume_specific('X'))
m_mode = Mode::HexadecimalUppercase;
else if (parser.consume_specific('c'))
m_mode = Mode::Character;
else if (parser.consume_specific('s'))
m_mode = Mode::String;
else if (parser.consume_specific('p'))
m_mode = Mode::Pointer;
else if (parser.consume_specific('f'))
m_mode = Mode::Float;
else if (parser.consume_specific('a'))
m_mode = Mode::Hexfloat;
else if (parser.consume_specific('A'))
m_mode = Mode::HexfloatUppercase;
if (!parser.is_eof())
dbgln("{} did not consume '{}'", __PRETTY_FUNCTION__, parser.remaining());
VERIFY(parser.is_eof());
}
void Formatter<StringView>::format(FormatBuilder& builder, StringView value)
{
if (m_sign_mode != FormatBuilder::SignMode::Default)
VERIFY_NOT_REACHED();
if (m_alternative_form)
VERIFY_NOT_REACHED();
if (m_zero_pad)
VERIFY_NOT_REACHED();
if (m_mode != Mode::Default && m_mode != Mode::String && m_mode != Mode::Character)
VERIFY_NOT_REACHED();
if (m_width.has_value() && m_precision.has_value())
VERIFY_NOT_REACHED();
m_width = m_width.value_or(0);
m_precision = m_precision.value_or(NumericLimits<size_t>::max());
builder.put_string(value, m_align, m_width.value(), m_precision.value(), m_fill);
}
void Formatter<FormatString>::vformat(FormatBuilder& builder, StringView fmtstr, TypeErasedFormatParams params)
{
return Formatter<String>::format(builder, String::vformatted(fmtstr, params));
}
template<typename T>
void Formatter<T, typename EnableIf<IsIntegral<T>>::Type>::format(FormatBuilder& builder, T value)
{
if (m_mode == Mode::Character) {
// FIXME: We just support ASCII for now, in the future maybe unicode?
VERIFY(value >= 0 && value <= 127);
m_mode = Mode::String;
Formatter<StringView> formatter { *this };
return formatter.format(builder, StringView { reinterpret_cast<const char*>(&value), 1 });
}
if (m_precision.has_value())
VERIFY_NOT_REACHED();
if (m_mode == Mode::Pointer) {
if (m_sign_mode != FormatBuilder::SignMode::Default)
VERIFY_NOT_REACHED();
if (m_align != FormatBuilder::Align::Default)
VERIFY_NOT_REACHED();
if (m_alternative_form)
VERIFY_NOT_REACHED();
if (m_width.has_value())
VERIFY_NOT_REACHED();
m_mode = Mode::Hexadecimal;
m_alternative_form = true;
m_width = 2 * sizeof(void*);
m_zero_pad = true;
}
u8 base = 0;
bool upper_case = false;
if (m_mode == Mode::Binary) {
base = 2;
} else if (m_mode == Mode::BinaryUppercase) {
base = 2;
upper_case = true;
} else if (m_mode == Mode::Octal) {
base = 8;
} else if (m_mode == Mode::Decimal || m_mode == Mode::Default) {
base = 10;
} else if (m_mode == Mode::Hexadecimal) {
base = 16;
} else if (m_mode == Mode::HexadecimalUppercase) {
base = 16;
upper_case = true;
} else {
VERIFY_NOT_REACHED();
}
m_width = m_width.value_or(0);
if constexpr (IsSame<MakeUnsigned<T>, T>)
builder.put_u64(value, base, m_alternative_form, upper_case, m_zero_pad, m_align, m_width.value(), m_fill, m_sign_mode);
else
builder.put_i64(value, base, m_alternative_form, upper_case, m_zero_pad, m_align, m_width.value(), m_fill, m_sign_mode);
}
void Formatter<char>::format(FormatBuilder& builder, char value)
{
if (m_mode == Mode::Binary || m_mode == Mode::BinaryUppercase || m_mode == Mode::Decimal || m_mode == Mode::Octal || m_mode == Mode::Hexadecimal || m_mode == Mode::HexadecimalUppercase) {
// Trick: signed char != char. (Sometimes weird features are actually helpful.)
Formatter<signed char> formatter { *this };
return formatter.format(builder, static_cast<signed char>(value));
} else {
Formatter<StringView> formatter { *this };
return formatter.format(builder, { &value, 1 });
}
}
void Formatter<bool>::format(FormatBuilder& builder, bool value)
{
if (m_mode == Mode::Binary || m_mode == Mode::BinaryUppercase || m_mode == Mode::Decimal || m_mode == Mode::Octal || m_mode == Mode::Hexadecimal || m_mode == Mode::HexadecimalUppercase) {
Formatter<u8> formatter { *this };
return formatter.format(builder, static_cast<u8>(value));
} else {
Formatter<StringView> formatter { *this };
return formatter.format(builder, value ? "true" : "false");
}
}
#ifndef KERNEL
void Formatter<double>::format(FormatBuilder& builder, double value)
{
u8 base;
bool upper_case;
if (m_mode == Mode::Default || m_mode == Mode::Float) {
base = 10;
upper_case = false;
} else if (m_mode == Mode::Hexfloat) {
base = 16;
upper_case = false;
} else if (m_mode == Mode::HexfloatUppercase) {
base = 16;
upper_case = true;
} else {
VERIFY_NOT_REACHED();
}
m_width = m_width.value_or(0);
m_precision = m_precision.value_or(6);
builder.put_f64(value, base, upper_case, m_align, m_width.value(), m_precision.value(), m_fill, m_sign_mode);
}
void Formatter<float>::format(FormatBuilder& builder, float value)
{
Formatter<double> formatter { *this };
formatter.format(builder, value);
}
#endif
#ifndef KERNEL
void vout(FILE* file, StringView fmtstr, TypeErasedFormatParams params, bool newline)
{
StringBuilder builder;
vformat(builder, fmtstr, params);
if (newline)
builder.append('\n');
const auto string = builder.string_view();
const auto retval = ::fwrite(string.characters_without_null_termination(), 1, string.length(), file);
if (static_cast<size_t>(retval) != string.length()) {
auto error = ferror(file);
dbgln("vout() failed ({} written out of {}), error was {} ({})", retval, string.length(), error, strerror(error));
}
}
#endif
static bool is_debug_enabled = true;
void set_debug_enabled(bool value)
{
is_debug_enabled = value;
}
void vdbgln(StringView fmtstr, TypeErasedFormatParams params)
{
if (!is_debug_enabled)
return;
StringBuilder builder;
#ifdef __serenity__
# ifdef KERNEL
if (Kernel::Processor::is_initialized() && Kernel::Thread::current()) {
auto& thread = *Kernel::Thread::current();
builder.appendff("\033[34;1m[#{} {}({}:{})]\033[0m: ", Kernel::Processor::id(), thread.process().name(), thread.pid().value(), thread.tid().value());
} else {
builder.appendff("\033[34;1m[#{} Kernel]\033[0m: ", Kernel::Processor::id());
}
# else
static TriState got_process_name = TriState::Unknown;
static char process_name_buffer[256];
if (got_process_name == TriState::Unknown) {
if (get_process_name(process_name_buffer, sizeof(process_name_buffer)) == 0)
got_process_name = TriState::True;
else
got_process_name = TriState::False;
}
if (got_process_name == TriState::True)
builder.appendff("\033[33;1m{}({}:{})\033[0m: ", process_name_buffer, getpid(), gettid());
# endif
#endif
vformat(builder, fmtstr, params);
builder.append('\n');
const auto string = builder.string_view();
dbgputstr(string.characters_without_null_termination(), string.length());
}
#ifdef KERNEL
void vdmesgln(StringView fmtstr, TypeErasedFormatParams params)
{
StringBuilder builder;
# ifdef __serenity__
if (Kernel::Processor::is_initialized() && Kernel::Thread::current()) {
auto& thread = *Kernel::Thread::current();
builder.appendff("\033[34;1m[{}({}:{})]\033[0m: ", thread.process().name(), thread.pid().value(), thread.tid().value());
} else {
builder.appendff("\033[34;1m[Kernel]\033[0m: ");
}
# endif
vformat(builder, fmtstr, params);
builder.append('\n');
const auto string = builder.string_view();
kernelputstr(string.characters_without_null_termination(), string.length());
}
void v_critical_dmesgln(StringView fmtstr, TypeErasedFormatParams params)
{
// FIXME: Try to avoid memory allocations further to prevent faulting
// at OOM conditions.
StringBuilder builder;
# ifdef __serenity__
if (Kernel::Processor::is_initialized() && Kernel::Thread::current()) {
auto& thread = *Kernel::Thread::current();
builder.appendff("[{}({}:{})]: ", thread.process().name(), thread.pid().value(), thread.tid().value());
} else {
builder.appendff("[Kernel]: ");
}
# endif
vformat(builder, fmtstr, params);
builder.append('\n');
const auto string = builder.string_view();
kernelcriticalputstr(string.characters_without_null_termination(), string.length());
}
#endif
template struct Formatter<unsigned char, void>;
template struct Formatter<unsigned short, void>;
template struct Formatter<unsigned int, void>;
template struct Formatter<unsigned long, void>;
template struct Formatter<unsigned long long, void>;
template struct Formatter<short, void>;
template struct Formatter<int, void>;
template struct Formatter<long, void>;
template struct Formatter<long long, void>;
template struct Formatter<signed char, void>;
} // namespace AK