ladybird/AK/String.cpp
Sergey Bugaev be6cce5530 AK: Add String::copy_characters_to_buffer()
This is a strcpy()-like method with actually sane semantics:

* It accepts a non-empty buffer along with its size in bytes.
* It copies as much of the string as fits into the buffer.
* It always null-terminates the result.
* It returns, as a non-discardable boolean, whether the whole string has been
copied.

Intended usage looks like this:

bool fits = string.copy_characters_to_buffer(buffer, sizeof(buffer));

and then either

if (!fits) {
    fprintf(stderr, "The name does not fit!!11");
    return nullptr;
}

or, if you're sure the buffer is large enough,

// I'm totally sure it fits because [reasons go here].
ASSERT(fits);

or if you're feeling extremely adventurous,

(void)fits;

but don't do that, please.
2020-08-30 17:35:27 +02:00

488 lines
12 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/FlyString.h>
#include <AK/Memory.h>
#include <AK/StdLibExtras.h>
#include <AK/String.h>
#include <AK/StringBuilder.h>
#include <AK/StringView.h>
#include <AK/Vector.h>
#ifndef KERNEL
# include <inttypes.h>
#endif
namespace AK {
String::String(const StringView& view)
{
if (view.m_impl)
m_impl = *view.m_impl;
else
m_impl = StringImpl::create(view.characters_without_null_termination(), view.length());
}
bool String::operator==(const FlyString& fly_string) const
{
return *this == String(fly_string.impl());
}
bool String::operator==(const String& other) const
{
if (!m_impl)
return !other.m_impl;
if (!other.m_impl)
return false;
if (length() != other.length())
return false;
return !memcmp(characters(), other.characters(), length());
}
bool String::operator==(const StringView& other) const
{
if (!m_impl)
return !other.m_characters;
if (!other.m_characters)
return false;
if (length() != other.length())
return false;
return !memcmp(characters(), other.characters_without_null_termination(), length());
}
bool String::operator<(const String& other) const
{
if (!m_impl)
return other.m_impl;
if (!other.m_impl)
return false;
return strcmp(characters(), other.characters()) < 0;
}
bool String::operator>(const String& other) const
{
if (!m_impl)
return other.m_impl;
if (!other.m_impl)
return false;
return strcmp(characters(), other.characters()) > 0;
}
String String::empty()
{
return StringImpl::the_empty_stringimpl();
}
bool String::copy_characters_to_buffer(char* buffer, size_t buffer_size) const
{
// We must fit at least the NUL-terminator.
ASSERT(buffer_size > 0);
size_t characters_to_copy = min(length(), buffer_size - 1);
__builtin_memcpy(buffer, characters(), characters_to_copy);
buffer[characters_to_copy] = 0;
return characters_to_copy == length();
}
String String::isolated_copy() const
{
if (!m_impl)
return {};
if (!m_impl->length())
return empty();
char* buffer;
auto impl = StringImpl::create_uninitialized(length(), buffer);
memcpy(buffer, m_impl->characters(), m_impl->length());
return String(move(*impl));
}
String String::substring(size_t start, size_t length) const
{
if (!length)
return "";
ASSERT(m_impl);
ASSERT(start + length <= m_impl->length());
// FIXME: This needs some input bounds checking.
return { characters() + start, length };
}
StringView String::substring_view(size_t start, size_t length) const
{
ASSERT(m_impl);
ASSERT(start + length <= m_impl->length());
// FIXME: This needs some input bounds checking.
return { characters() + start, length };
}
Vector<String> String::split(char separator, bool keep_empty) const
{
return split_limit(separator, 0, keep_empty);
}
Vector<String> String::split_limit(char separator, size_t limit, bool keep_empty) const
{
if (is_empty())
return {};
Vector<String> v;
size_t substart = 0;
for (size_t i = 0; i < length() && (v.size() + 1) != limit; ++i) {
char ch = characters()[i];
if (ch == separator) {
size_t sublen = i - substart;
if (sublen != 0 || keep_empty)
v.append(substring(substart, sublen));
substart = i + 1;
}
}
size_t taillen = length() - substart;
if (taillen != 0 || keep_empty)
v.append(substring(substart, taillen));
return v;
}
Vector<StringView> String::split_view(const char separator, bool keep_empty) const
{
if (is_empty())
return {};
Vector<StringView> v;
size_t substart = 0;
for (size_t i = 0; i < length(); ++i) {
char ch = characters()[i];
if (ch == separator) {
size_t sublen = i - substart;
if (sublen != 0 || keep_empty)
v.append(substring_view(substart, sublen));
substart = i + 1;
}
}
size_t taillen = length() - substart;
if (taillen != 0 || keep_empty)
v.append(substring_view(substart, taillen));
return v;
}
ByteBuffer String::to_byte_buffer() const
{
if (!m_impl)
return nullptr;
return ByteBuffer::copy(reinterpret_cast<const u8*>(characters()), length());
}
Optional<int> String::to_int() const
{
return StringUtils::convert_to_int(view());
}
Optional<unsigned> String::to_uint() const
{
return StringUtils::convert_to_uint(view());
}
String String::number(unsigned long long value)
{
int size;
char buffer[32];
size = snprintf(buffer, sizeof(buffer), "%llu", value);
return String(buffer, size);
}
String String::number(unsigned long value)
{
int size;
char buffer[32];
size = snprintf(buffer, sizeof(buffer), "%lu", value);
return String(buffer, size);
}
String String::number(unsigned value)
{
char buffer[32];
int size = snprintf(buffer, sizeof(buffer), "%u", value);
return String(buffer, size);
}
String String::number(long long value)
{
char buffer[32];
int size = snprintf(buffer, sizeof(buffer), "%lld", value);
return String(buffer, size);
}
String String::number(long value)
{
char buffer[32];
int size = snprintf(buffer, sizeof(buffer), "%ld", value);
return String(buffer, size);
}
String String::number(int value)
{
char buffer[32];
int size = snprintf(buffer, sizeof(buffer), "%d", value);
return String(buffer, size);
}
String String::format(const char* fmt, ...)
{
StringBuilder builder;
va_list ap;
va_start(ap, fmt);
builder.appendvf(fmt, ap);
va_end(ap);
return builder.to_string();
}
bool String::starts_with(const StringView& str, CaseSensitivity case_sensitivity) const
{
return StringUtils::starts_with(*this, str, case_sensitivity);
}
bool String::starts_with(char ch) const
{
if (is_empty())
return false;
return characters()[0] == ch;
}
bool String::ends_with(const StringView& str, CaseSensitivity case_sensitivity) const
{
return StringUtils::ends_with(*this, str, case_sensitivity);
}
bool String::ends_with(char ch) const
{
if (is_empty())
return false;
return characters()[length() - 1] == ch;
}
String String::repeated(char ch, size_t count)
{
if (!count)
return empty();
char* buffer;
auto impl = StringImpl::create_uninitialized(count, buffer);
memset(buffer, ch, count);
return *impl;
}
bool String::matches(const StringView& mask, CaseSensitivity case_sensitivity) const
{
return StringUtils::matches(*this, mask, case_sensitivity);
}
bool String::contains(const String& needle) const
{
if (is_null() || needle.is_null())
return false;
return strstr(characters(), needle.characters());
}
Optional<size_t> String::index_of(const String& needle, size_t start) const
{
if (is_null() || needle.is_null())
return {};
const char* self_characters = characters();
const char* result = strstr(self_characters + start, needle.characters());
if (!result)
return {};
return Optional<size_t> { result - self_characters };
}
bool String::equals_ignoring_case(const StringView& other) const
{
return StringUtils::equals_ignoring_case(view(), other);
}
int String::replace(const String& needle, const String& replacement, bool all_occurences)
{
if (is_empty())
return 0;
Vector<size_t> positions;
size_t start = 0, pos;
for (;;) {
const char* ptr = strstr(characters() + start, needle.characters());
if (!ptr)
break;
pos = ptr - characters();
positions.append(pos);
if (!all_occurences)
break;
start = pos + 1;
}
if (!positions.size())
return 0;
StringBuilder b;
size_t lastpos = 0;
for (auto& pos : positions) {
b.append(substring_view(lastpos, pos - lastpos));
b.append(replacement);
lastpos = pos + needle.length();
}
b.append(substring_view(lastpos, length() - lastpos));
m_impl = StringImpl::create(b.build().characters());
return positions.size();
}
String String::trim_whitespace(TrimMode mode) const
{
auto is_whitespace_character = [](char ch) -> bool {
return ch == '\t'
|| ch == '\n'
|| ch == '\v'
|| ch == '\f'
|| ch == '\r'
|| ch == ' ';
};
size_t substring_start = 0;
size_t substring_length = length();
if (mode == TrimMode::Left || mode == TrimMode::Both) {
for (size_t i = 0; i < length(); ++i) {
if (substring_length == 0)
return "";
if (!is_whitespace_character(characters()[i]))
break;
++substring_start;
--substring_length;
}
}
if (mode == TrimMode::Right || mode == TrimMode::Both) {
for (size_t i = length() - 1; i > 0; --i) {
if (substring_length == 0)
return "";
if (!is_whitespace_character(characters()[i]))
break;
--substring_length;
}
}
return substring(substring_start, substring_length);
}
String escape_html_entities(const StringView& html)
{
StringBuilder builder;
for (size_t i = 0; i < html.length(); ++i) {
if (html[i] == '<')
builder.append("&lt;");
else if (html[i] == '>')
builder.append("&gt;");
else if (html[i] == '&')
builder.append("&amp;");
else
builder.append(html[i]);
}
return builder.to_string();
}
String::String(const FlyString& string)
: m_impl(string.impl())
{
}
String String::to_lowercase() const
{
if (!m_impl)
return {};
return m_impl->to_lowercase();
}
String String::to_uppercase() const
{
if (!m_impl)
return {};
return m_impl->to_uppercase();
}
bool operator<(const char* characters, const String& string)
{
if (!characters)
return !string.is_null();
if (string.is_null())
return false;
return __builtin_strcmp(characters, string.characters()) < 0;
}
bool operator>=(const char* characters, const String& string)
{
return !(characters < string);
}
bool operator>(const char* characters, const String& string)
{
if (!characters)
return !string.is_null();
if (string.is_null())
return false;
return __builtin_strcmp(characters, string.characters()) > 0;
}
bool operator<=(const char* characters, const String& string)
{
return !(characters > string);
}
bool String::operator==(const char* cstring) const
{
if (is_null())
return !cstring;
if (!cstring)
return false;
return !__builtin_strcmp(characters(), cstring);
}
StringView String::view() const
{
return { characters(), length() };
}
}