ladybird/AK/StringBuilder.cpp
Lucas CHOLLET 62b8ccaffc StringBuilder: Add try_append_repeated() and append_repeated()
This two methods add the character as many times as specified by the
second parameter.
2022-09-15 14:08:21 +01:00

221 lines
4.9 KiB
C++

/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/ByteBuffer.h>
#include <AK/Checked.h>
#include <AK/PrintfImplementation.h>
#include <AK/StdLibExtras.h>
#include <AK/StringBuilder.h>
#include <AK/StringView.h>
#include <AK/UnicodeUtils.h>
#include <AK/Utf32View.h>
#ifndef KERNEL
# include <AK/String.h>
# include <AK/Utf16View.h>
#endif
namespace AK {
inline ErrorOr<void> StringBuilder::will_append(size_t size)
{
Checked<size_t> needed_capacity = m_buffer.size();
needed_capacity += size;
VERIFY(!needed_capacity.has_overflow());
// Prefer to completely use the existing capacity first
if (needed_capacity <= m_buffer.capacity())
return {};
Checked<size_t> expanded_capacity = needed_capacity;
expanded_capacity *= 2;
VERIFY(!expanded_capacity.has_overflow());
TRY(m_buffer.try_ensure_capacity(expanded_capacity.value()));
return {};
}
StringBuilder::StringBuilder(size_t initial_capacity)
{
m_buffer.ensure_capacity(initial_capacity);
}
ErrorOr<void> StringBuilder::try_append(StringView string)
{
if (string.is_empty())
return {};
TRY(will_append(string.length()));
TRY(m_buffer.try_append(string.characters_without_null_termination(), string.length()));
return {};
}
ErrorOr<void> StringBuilder::try_append(char ch)
{
TRY(will_append(1));
TRY(m_buffer.try_append(ch));
return {};
}
ErrorOr<void> StringBuilder::try_append_repeated(char ch, size_t n)
{
TRY(will_append(n));
for (size_t i = 0; i < n; ++i)
TRY(try_append(ch));
return {};
}
void StringBuilder::append(StringView string)
{
MUST(try_append(string));
}
ErrorOr<void> StringBuilder::try_append(char const* characters, size_t length)
{
return try_append(StringView { characters, length });
}
void StringBuilder::append(char const* characters, size_t length)
{
MUST(try_append(characters, length));
}
void StringBuilder::append(char ch)
{
MUST(try_append(ch));
}
void StringBuilder::appendvf(char const* fmt, va_list ap)
{
printf_internal([this](char*&, char ch) {
append(ch);
},
nullptr, fmt, ap);
}
void StringBuilder::append_repeated(char ch, size_t n)
{
MUST(try_append_repeated(ch, n));
}
ByteBuffer StringBuilder::to_byte_buffer() const
{
// FIXME: Handle OOM failure.
return ByteBuffer::copy(data(), length()).release_value_but_fixme_should_propagate_errors();
}
#ifndef KERNEL
String StringBuilder::to_string() const
{
if (is_empty())
return String::empty();
return String((char const*)data(), length());
}
String StringBuilder::build() const
{
return to_string();
}
#endif
StringView StringBuilder::string_view() const
{
return StringView { data(), m_buffer.size() };
}
void StringBuilder::clear()
{
m_buffer.clear();
}
ErrorOr<void> StringBuilder::try_append_code_point(u32 code_point)
{
auto nwritten = AK::UnicodeUtils::code_point_to_utf8(code_point, [this](char c) { append(c); });
if (nwritten < 0) {
TRY(try_append(0xef));
TRY(try_append(0xbf));
TRY(try_append(0xbd));
}
return {};
}
void StringBuilder::append_code_point(u32 code_point)
{
MUST(try_append_code_point(code_point));
}
#ifndef KERNEL
ErrorOr<void> StringBuilder::try_append(Utf16View const& utf16_view)
{
for (size_t i = 0; i < utf16_view.length_in_code_units();) {
auto code_point = utf16_view.code_point_at(i);
TRY(try_append_code_point(code_point));
i += (code_point > 0xffff ? 2 : 1);
}
return {};
}
void StringBuilder::append(Utf16View const& utf16_view)
{
MUST(try_append(utf16_view));
}
#endif
ErrorOr<void> StringBuilder::try_append(Utf32View const& utf32_view)
{
for (size_t i = 0; i < utf32_view.length(); ++i) {
auto code_point = utf32_view.code_points()[i];
TRY(try_append_code_point(code_point));
}
return {};
}
void StringBuilder::append(Utf32View const& utf32_view)
{
MUST(try_append(utf32_view));
}
void StringBuilder::append_as_lowercase(char ch)
{
if (ch >= 'A' && ch <= 'Z')
append(ch + 0x20);
else
append(ch);
}
void StringBuilder::append_escaped_for_json(StringView string)
{
MUST(try_append_escaped_for_json(string));
}
ErrorOr<void> StringBuilder::try_append_escaped_for_json(StringView string)
{
for (auto ch : string) {
switch (ch) {
case '\b':
TRY(try_append("\\b"sv));
break;
case '\n':
TRY(try_append("\\n"sv));
break;
case '\t':
TRY(try_append("\\t"sv));
break;
case '\"':
TRY(try_append("\\\""sv));
break;
case '\\':
TRY(try_append("\\\\"sv));
break;
default:
if (ch >= 0 && ch <= 0x1f)
TRY(try_appendff("\\u{:04x}", ch));
else
TRY(try_append(ch));
}
}
return {};
}
}