- UString::BaseString* base = rep->baseString();
-
- if (requiredLength > base->capacity) {
- size_t newCapacity = expandedSize(requiredLength, base->preCapacity);
- UChar* oldBuf = base->buf;
- base->buf = reallocChars(base->buf, newCapacity);
- if (!base->buf) {
- base->buf = oldBuf;
- return false;
- }
- base->capacity = newCapacity - base->preCapacity;
- }
- if (requiredLength > base->usedCapacity)
- base->usedCapacity = requiredLength;
-
- rep->checkConsistency();
- return true;
-}
-
-bool UString::Rep::reserveCapacity(int capacity)
-{
- // If this is an empty string there is no point 'growing' it - just allocate a new one.
- // If the BaseString is shared with another string that is using more capacity than this
- // string is, then growing the buffer won't help.
- // If the BaseString's buffer is readonly, then it isn't allowed to grow.
- UString::BaseString* base = baseString();
- if (!base->buf || !base->capacity || (offset + len) != base->usedCapacity || base->isBufferReadOnly())
- return false;
-
- // If there is already sufficient capacity, no need to grow!
- if (capacity <= base->capacity)
- return true;
-
- checkConsistency();
-
- size_t newCapacity = expandedSize(capacity, base->preCapacity);
- UChar* oldBuf = base->buf;
- base->buf = reallocChars(base->buf, newCapacity);
- if (!base->buf) {
- base->buf = oldBuf;
- return false;
- }
- base->capacity = newCapacity - base->preCapacity;
-
- checkConsistency();
- return true;
-}
-
-void UString::expandCapacity(int requiredLength)
-{
- if (!JSC::expandCapacity(m_rep.get(), requiredLength))
- makeNull();
-}
-
-void UString::expandPreCapacity(int requiredPreCap)
-{
- m_rep->checkConsistency();
- ASSERT(!m_rep->baseString()->isBufferReadOnly());
-
- BaseString* base = m_rep->baseString();
-
- if (requiredPreCap > base->preCapacity) {
- size_t newCapacity = expandedSize(requiredPreCap, base->capacity);
- int delta = newCapacity - base->capacity - base->preCapacity;
-
- UChar* newBuf = allocChars(newCapacity);
- if (!newBuf) {
- makeNull();
- return;
- }
- copyChars(newBuf + delta, base->buf, base->capacity + base->preCapacity);
- fastFree(base->buf);
- base->buf = newBuf;
-
- base->preCapacity = newCapacity - base->capacity;
- }
- if (requiredPreCap > base->usedPreCapacity)
- base->usedPreCapacity = requiredPreCap;
-
- m_rep->checkConsistency();
-}
-
-static PassRefPtr<UString::Rep> createRep(const char* c)
-{
- if (!c)
- return &UString::Rep::null();
-
- if (!c[0])
- return &UString::Rep::empty();
-
- size_t length = strlen(c);
- UChar* d = allocChars(length);
- if (!d)
- return &UString::Rep::null();
- else {
- for (size_t i = 0; i < length; i++)
- d[i] = static_cast<unsigned char>(c[i]); // use unsigned char to zero-extend instead of sign-extend
- return UString::Rep::create(d, static_cast<int>(length));
- }
-
-}
-
-UString::UString(const char* c)
- : m_rep(createRep(c))
-{
-}
-
-UString::UString(const UChar* c, int length)
-{
- if (length == 0)
- m_rep = &Rep::empty();
- else
- m_rep = Rep::createCopying(c, length);
-}
-
-UString::UString(UChar* c, int length, bool copy)
-{
- if (length == 0)
- m_rep = &Rep::empty();
- else if (copy)
- m_rep = Rep::createCopying(c, length);
- else
- m_rep = Rep::create(c, length);
-}
-
-UString::UString(const Vector<UChar>& buffer)
-{
- if (!buffer.size())
- m_rep = &Rep::empty();
- else
- m_rep = Rep::createCopying(buffer.data(), buffer.size());
-}
-
-static ALWAYS_INLINE int newCapacityWithOverflowCheck(const int currentCapacity, const int extendLength, const bool plusOne = false)
-{
- ASSERT_WITH_MESSAGE(extendLength >= 0, "extendedLength = %d", extendLength);
-
- const int plusLength = plusOne ? 1 : 0;
- if (currentCapacity > std::numeric_limits<int>::max() - extendLength - plusLength)
- CRASH();
-
- return currentCapacity + extendLength + plusLength;
-}
-
-static ALWAYS_INLINE PassRefPtr<UString::Rep> concatenate(PassRefPtr<UString::Rep> r, const UChar* tData, int tSize)
-{
- RefPtr<UString::Rep> rep = r;
-
- rep->checkConsistency();
-
- int thisSize = rep->size();
- int thisOffset = rep->offset;
- int length = thisSize + tSize;
- UString::BaseString* base = rep->baseString();
-
- // possible cases:
- if (tSize == 0) {
- // t is empty
- } else if (thisSize == 0) {
- // this is empty
- rep = UString::Rep::createCopying(tData, tSize);
- } else if (rep == base && !base->isShared()) {
- // this is direct and has refcount of 1 (so we can just alter it directly)
- if (!expandCapacity(rep.get(), newCapacityWithOverflowCheck(thisOffset, length)))
- rep = &UString::Rep::null();
- if (rep->data()) {
- copyChars(rep->data() + thisSize, tData, tSize);
- rep->len = length;
- rep->_hash = 0;
- }
- } else if (thisOffset + thisSize == base->usedCapacity && thisSize >= minShareSize && !base->isBufferReadOnly()) {
- // this reaches the end of the buffer - extend it if it's long enough to append to
- if (!expandCapacity(rep.get(), newCapacityWithOverflowCheck(thisOffset, length)))
- rep = &UString::Rep::null();
- if (rep->data()) {
- copyChars(rep->data() + thisSize, tData, tSize);
- rep = UString::Rep::create(rep, 0, length);
- }
- } else {
- // This is shared in some way that prevents us from modifying base, so we must make a whole new string.
- size_t newCapacity = expandedSize(length, 0);
- UChar* d = allocChars(newCapacity);
- if (!d)
- rep = &UString::Rep::null();
- else {
- copyChars(d, rep->data(), thisSize);
- copyChars(d + thisSize, tData, tSize);
- rep = UString::Rep::create(d, length);
- rep->baseString()->capacity = newCapacity;
- }
- }
-
- rep->checkConsistency();
-
- return rep.release();
-}
-
-static ALWAYS_INLINE PassRefPtr<UString::Rep> concatenate(PassRefPtr<UString::Rep> r, const char* t)
-{
- RefPtr<UString::Rep> rep = r;
-
- rep->checkConsistency();
-
- int thisSize = rep->size();
- int thisOffset = rep->offset;
- int tSize = static_cast<int>(strlen(t));
- int length = thisSize + tSize;
- UString::BaseString* base = rep->baseString();
-
- // possible cases:
- if (thisSize == 0) {
- // this is empty
- rep = createRep(t);
- } else if (tSize == 0) {
- // t is empty, we'll just return *this below.
- } else if (rep == base && !base->isShared()) {
- // this is direct and has refcount of 1 (so we can just alter it directly)
- expandCapacity(rep.get(), newCapacityWithOverflowCheck(thisOffset, length));
- UChar* d = rep->data();
- if (d) {
- for (int i = 0; i < tSize; ++i)
- d[thisSize + i] = static_cast<unsigned char>(t[i]); // use unsigned char to zero-extend instead of sign-extend
- rep->len = length;
- rep->_hash = 0;
- }
- } else if (thisOffset + thisSize == base->usedCapacity && thisSize >= minShareSize && !base->isBufferReadOnly()) {
- // this string reaches the end of the buffer - extend it
- expandCapacity(rep.get(), newCapacityWithOverflowCheck(thisOffset, length));
- UChar* d = rep->data();
- if (d) {
- for (int i = 0; i < tSize; ++i)
- d[thisSize + i] = static_cast<unsigned char>(t[i]); // use unsigned char to zero-extend instead of sign-extend
- rep = UString::Rep::create(rep, 0, length);
- }
- } else {
- // This is shared in some way that prevents us from modifying base, so we must make a whole new string.
- size_t newCapacity = expandedSize(length, 0);
- UChar* d = allocChars(newCapacity);
- if (!d)
- rep = &UString::Rep::null();
- else {
- copyChars(d, rep->data(), thisSize);
- for (int i = 0; i < tSize; ++i)
- d[thisSize + i] = static_cast<unsigned char>(t[i]); // use unsigned char to zero-extend instead of sign-extend
- rep = UString::Rep::create(d, length);
- rep->baseString()->capacity = newCapacity;
- }
- }
-
- rep->checkConsistency();
-
- return rep.release();
-}
-
-PassRefPtr<UString::Rep> concatenate(UString::Rep* a, UString::Rep* b)
-{
- a->checkConsistency();
- b->checkConsistency();
-
- int aSize = a->size();
- int bSize = b->size();
- int aOffset = a->offset;
-
- // possible cases:
-
- UString::BaseString* aBase = a->baseString();
- if (bSize == 1 && aOffset + aSize == aBase->usedCapacity && aOffset + aSize < aBase->capacity && !aBase->isBufferReadOnly()) {
- // b is a single character (common fast case)
- ++aBase->usedCapacity;
- a->data()[aSize] = b->data()[0];
- return UString::Rep::create(a, 0, aSize + 1);
- }
-
- // a is empty
- if (aSize == 0)
- return b;
- // b is empty
- if (bSize == 0)
- return a;
-
- int bOffset = b->offset;
- int length = aSize + bSize;
-
- UString::BaseString* bBase = b->baseString();
- if (aOffset + aSize == aBase->usedCapacity && aSize >= minShareSize && 4 * aSize >= bSize
- && (-bOffset != bBase->usedPreCapacity || aSize >= bSize) && !aBase->isBufferReadOnly()) {
- // - a reaches the end of its buffer so it qualifies for shared append
- // - also, it's at least a quarter the length of b - appending to a much shorter
- // string does more harm than good
- // - however, if b qualifies for prepend and is longer than a, we'd rather prepend
-
- UString x(a);
- x.expandCapacity(newCapacityWithOverflowCheck(aOffset, length));
- if (!a->data() || !x.data())
- return 0;
- copyChars(a->data() + aSize, b->data(), bSize);
- PassRefPtr<UString::Rep> result = UString::Rep::create(a, 0, length);
-
- a->checkConsistency();
- b->checkConsistency();
- result->checkConsistency();
-
- return result;
- }
-
- if (-bOffset == bBase->usedPreCapacity && bSize >= minShareSize && 4 * bSize >= aSize && !bBase->isBufferReadOnly()) {
- // - b reaches the beginning of its buffer so it qualifies for shared prepend
- // - also, it's at least a quarter the length of a - prepending to a much shorter
- // string does more harm than good
- UString y(b);
- y.expandPreCapacity(-bOffset + aSize);
- if (!b->data() || !y.data())
- return 0;
- copyChars(b->data() - aSize, a->data(), aSize);
- PassRefPtr<UString::Rep> result = UString::Rep::create(b, -aSize, length);
-
- a->checkConsistency();
- b->checkConsistency();
- result->checkConsistency();
-
- return result;
- }
-
- // a does not qualify for append, and b does not qualify for prepend, gotta make a whole new string
- size_t newCapacity = expandedSize(length, 0);
- UChar* d = allocChars(newCapacity);
- if (!d)
- return 0;
- copyChars(d, a->data(), aSize);
- copyChars(d + aSize, b->data(), bSize);
- PassRefPtr<UString::Rep> result = UString::Rep::create(d, length);
- result->baseString()->capacity = newCapacity;
-
- a->checkConsistency();
- b->checkConsistency();
- result->checkConsistency();
-
- return result;
-}
-
-PassRefPtr<UString::Rep> concatenate(UString::Rep* rep, int i)
-{
- UChar buf[1 + sizeof(i) * 3];
- UChar* end = buf + sizeof(buf) / sizeof(UChar);
- UChar* p = end;
-
projects / apple / javascriptcore.git / blobdiff