- typedef CrossThreadRefCounted<OwnFastMallocPtr<UChar> > SharedUChar;
- struct BaseString;
- struct Rep : Noncopyable {
- friend class JIT;
-
- static PassRefPtr<Rep> create(UChar* buffer, int length)
- {
- return adoptRef(new BaseString(buffer, length));
- }
-
- static PassRefPtr<Rep> createEmptyBuffer(size_t size)
- {
- // Guard against integer overflow
- if (size < (std::numeric_limits<size_t>::max() / sizeof(UChar))) {
- if (void * buf = tryFastMalloc(size * sizeof(UChar)))
- return adoptRef(new BaseString(static_cast<UChar*>(buf), 0, size));
- }
- return adoptRef(new BaseString(0, 0, 0));
- }
-
- static PassRefPtr<Rep> createCopying(const UChar*, int);
- static PassRefPtr<Rep> create(PassRefPtr<Rep> base, int offset, int length);
-
- // Constructs a string from a UTF-8 string, using strict conversion (see comments in UTF8.h).
- // Returns UString::Rep::null for null input or conversion failure.
- static PassRefPtr<Rep> createFromUTF8(const char*);
-
- // Uses SharedUChar to have joint ownership over the UChar*.
- static PassRefPtr<Rep> create(UChar*, int, PassRefPtr<SharedUChar>);
-
- SharedUChar* sharedBuffer();
- void destroy();
-
- bool baseIsSelf() const { return m_identifierTableAndFlags.isFlagSet(BaseStringFlag); }
- UChar* data() const;
- int size() const { return len; }
-
- unsigned hash() const { if (_hash == 0) _hash = computeHash(data(), len); return _hash; }
- unsigned computedHash() const { ASSERT(_hash); return _hash; } // fast path for Identifiers
-
- static unsigned computeHash(const UChar*, int length);
- static unsigned computeHash(const char*, int length);
- static unsigned computeHash(const char* s) { return computeHash(s, strlen(s)); }
-
- IdentifierTable* identifierTable() const { return m_identifierTableAndFlags.get(); }
- void setIdentifierTable(IdentifierTable* table) { ASSERT(!isStatic()); m_identifierTableAndFlags.set(table); }
-
- bool isStatic() const { return m_identifierTableAndFlags.isFlagSet(StaticFlag); }
- void setStatic(bool);
- void setBaseString(PassRefPtr<BaseString>);
- BaseString* baseString();
- const BaseString* baseString() const;
-
- Rep* ref() { ++rc; return this; }
- ALWAYS_INLINE void deref() { if (--rc == 0) destroy(); }
-
- void checkConsistency() const;
- enum UStringFlags {
- StaticFlag,
- BaseStringFlag
- };
-
- // unshared data
- int offset;
- int len;
- int rc; // For null and empty static strings, this field does not reflect a correct count, because ref/deref are not thread-safe. A special case in destroy() guarantees that these do not get deleted.
- mutable unsigned _hash;
- PtrAndFlags<IdentifierTable, UStringFlags> m_identifierTableAndFlags;
-
- static BaseString& null() { return *nullBaseString; }
- static BaseString& empty() { return *emptyBaseString; }
-
- bool reserveCapacity(int capacity);
-
- protected:
- // Constructor for use by BaseString subclass; they use the union with m_baseString for another purpose.
- Rep(int length)
- : offset(0)
- , len(length)
- , rc(1)
- , _hash(0)
- , m_baseString(0)
- {
- }
-
- Rep(PassRefPtr<BaseString> base, int offsetInBase, int length)
- : offset(offsetInBase)
- , len(length)
- , rc(1)
- , _hash(0)
- , m_baseString(base.releaseRef())
- {
- checkConsistency();
- }
-
- union {
- // If !baseIsSelf()
- BaseString* m_baseString;
- // If baseIsSelf()
- SharedUChar* m_sharedBuffer;
- };
-
- private:
- // For SmallStringStorage which allocates an array and does initialization manually.
- Rep() { }
-
- friend class SmallStringsStorage;
- friend void initializeUString();
- JS_EXPORTDATA static BaseString* nullBaseString;
- JS_EXPORTDATA static BaseString* emptyBaseString;
- };
-
-
- struct BaseString : public Rep {
- bool isShared() { return rc != 1 || isBufferReadOnly(); }
- void setSharedBuffer(PassRefPtr<SharedUChar>);
-
- bool isBufferReadOnly()
- {
- if (!m_sharedBuffer)
- return false;
- return slowIsBufferReadOnly();
- }
-
- // potentially shared data.
- UChar* buf;
- int preCapacity;
- int usedPreCapacity;
- int capacity;
- int usedCapacity;
-
- size_t reportedCost;
-
- private:
- BaseString(UChar* buffer, int length, int additionalCapacity = 0)
- : Rep(length)
- , buf(buffer)
- , preCapacity(0)
- , usedPreCapacity(0)
- , capacity(length + additionalCapacity)
- , usedCapacity(length)
- , reportedCost(0)
- {
- m_identifierTableAndFlags.setFlag(BaseStringFlag);
- checkConsistency();
- }
-
- SharedUChar* sharedBuffer();
- bool slowIsBufferReadOnly();
-
- friend struct Rep;
- friend class SmallStringsStorage;
- friend void initializeUString();
- };
-
projects / apple / javascriptcore.git / blobdiff