ladybird/AK/String.cpp

273 lines
6.5 KiB
C++

#include "AKString.h"
#include "StdLibExtras.h"
#include "StringBuilder.h"
#include <stdarg.h>
namespace AK {
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 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();
}
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(int start, int 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(int start, int 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 };
}
Vector<String> String::split(const char separator) const
{
return split_limit(separator, 0);
}
Vector<String> String::split_limit(const char separator, int limit) const
{
if (is_empty())
return {};
Vector<String> v;
int substart = 0;
for (int i = 0; i < length() && (v.size() + 1) != limit; ++i) {
char ch = characters()[i];
if (ch == separator) {
int sublen = i - substart;
if (sublen != 0)
v.append(substring(substart, sublen));
substart = i + 1;
}
}
int taillen = length() - substart;
if (taillen != 0)
v.append(substring(substart, taillen));
if (characters()[length() - 1] == separator)
v.append(empty());
return v;
}
Vector<StringView> String::split_view(const char separator) const
{
if (is_empty())
return {};
Vector<StringView> v;
int substart = 0;
for (int i = 0; i < length(); ++i) {
char ch = characters()[i];
if (ch == separator) {
int sublen = i - substart;
if (sublen != 0)
v.append(substring_view(substart, sublen));
substart = i + 1;
}
}
int taillen = length() - substart;
if (taillen != 0)
v.append(substring_view(substart, taillen));
if (characters()[length() - 1] == separator)
v.append(empty());
return v;
}
ByteBuffer String::to_byte_buffer() const
{
if (!m_impl)
return nullptr;
return ByteBuffer::copy(reinterpret_cast<const byte*>(characters()), length());
}
int String::to_int(bool& ok) const
{
bool negative = false;
int value = 0;
int i = 0;
if (is_null()) {
ok = false;
return 0;
}
if (characters()[0] == '-') {
i++;
negative = true;
}
for (; i < length(); i++) {
if (characters()[i] < '0' || characters()[i] > '9') {
ok = false;
return 0;
}
value = value * 10;
value += characters()[i] - '0';
}
ok = true;
return negative ? -value : value;
}
unsigned String::to_uint(bool& ok) const
{
unsigned value = 0;
for (int i = 0; i < length(); ++i) {
if (characters()[i] < '0' || characters()[i] > '9') {
ok = false;
return 0;
}
value = value * 10;
value += characters()[i] - '0';
}
ok = true;
return value;
}
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) const
{
if (str.is_empty())
return true;
if (is_empty())
return false;
if (str.length() > length())
return false;
return !memcmp(characters(), str.characters(), str.length());
}
bool String::ends_with(const StringView& str) const
{
if (str.is_empty())
return true;
if (is_empty())
return false;
if (str.length() > length())
return false;
return !memcmp(characters() + (length() - str.length()), str.characters(), str.length());
}
String String::repeated(char ch, int 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
{
if (case_sensitivity == CaseSensitivity::CaseInsensitive) {
String this_lower = this->to_lowercase();
String mask_lower = String(mask).to_lowercase();
return this_lower.match_helper(mask_lower);
}
return match_helper(mask);
}
bool String::match_helper(const StringView& mask) const
{
if (is_null())
return false;
const char* string_ptr = characters();
const char* mask_ptr = mask.characters();
const char* mask_end = mask_ptr + mask.length();
// Match string against mask directly unless we hit a *
while ((*string_ptr) && (mask_ptr < mask_end) && (*mask_ptr != '*')) {
if ((*mask_ptr != *string_ptr) && (*mask_ptr != '?'))
return false;
mask_ptr++;
string_ptr++;
}
const char* cp = nullptr;
const char* mp = nullptr;
while (*string_ptr) {
if ((mask_ptr < mask_end) && (*mask_ptr == '*')) {
// If we have only a * left, there is no way to not match.
if (++mask_ptr == mask_end)
return true;
mp = mask_ptr;
cp = string_ptr + 1;
} else if ((mask_ptr < mask_end) && ((*mask_ptr == *string_ptr) || (*mask_ptr == '?'))) {
mask_ptr++;
string_ptr++;
} else if ((cp != nullptr) && (mp != nullptr)) {
mask_ptr = mp;
string_ptr = cp++;
} else {
break;
}
}
// Handle any trailing mask
while ((mask_ptr < mask_end) && (*mask_ptr == '*'))
mask_ptr++;
// If we 'ate' all of the mask and the string then we match.
return (mask_ptr == mask_end) && !*string_ptr;
}
}