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Diffstat (limited to 'runtime/mirror/string.cc')
-rw-r--r-- | runtime/mirror/string.cc | 290 |
1 files changed, 290 insertions, 0 deletions
diff --git a/runtime/mirror/string.cc b/runtime/mirror/string.cc new file mode 100644 index 0000000000..97126cba4c --- /dev/null +++ b/runtime/mirror/string.cc @@ -0,0 +1,290 @@ +/* + * Copyright (C) 2011 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "string.h" + +#include "array.h" +#include "gc/accounting/card_table-inl.h" +#include "intern_table.h" +#include "object-inl.h" +#include "runtime.h" +#include "sirt_ref.h" +#include "thread.h" +#include "utf.h" + +namespace art { +namespace mirror { + +const CharArray* String::GetCharArray() const { + return GetFieldObject<const CharArray*>(ValueOffset(), false); +} + +void String::ComputeHashCode() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { + SetHashCode(ComputeUtf16Hash(GetCharArray(), GetOffset(), GetLength())); +} + +int32_t String::GetUtfLength() const { + return CountUtf8Bytes(GetCharArray()->GetData() + GetOffset(), GetLength()); +} + +int32_t String::FastIndexOf(int32_t ch, int32_t start) const { + int32_t count = GetLength(); + if (start < 0) { + start = 0; + } else if (start > count) { + start = count; + } + const uint16_t* chars = GetCharArray()->GetData() + GetOffset(); + const uint16_t* p = chars + start; + const uint16_t* end = chars + count; + while (p < end) { + if (*p++ == ch) { + return (p - 1) - chars; + } + } + return -1; +} + +void String::SetArray(CharArray* new_array) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { + DCHECK(new_array != NULL); + SetFieldObject(OFFSET_OF_OBJECT_MEMBER(String, array_), new_array, false); +} + +// TODO: get global references for these +Class* String::java_lang_String_ = NULL; + +void String::SetClass(Class* java_lang_String) { + CHECK(java_lang_String_ == NULL); + CHECK(java_lang_String != NULL); + java_lang_String_ = java_lang_String; +} + +void String::ResetClass() { + CHECK(java_lang_String_ != NULL); + java_lang_String_ = NULL; +} + +String* String::Intern() { + return Runtime::Current()->GetInternTable()->InternWeak(this); +} + +int32_t String::GetHashCode() { + int32_t result = GetField32(OFFSET_OF_OBJECT_MEMBER(String, hash_code_), false); + if (result == 0) { + ComputeHashCode(); + } + result = GetField32(OFFSET_OF_OBJECT_MEMBER(String, hash_code_), false); + DCHECK(result != 0 || ComputeUtf16Hash(GetCharArray(), GetOffset(), GetLength()) == 0) + << ToModifiedUtf8() << " " << result; + return result; +} + +int32_t String::GetLength() const { + int32_t result = GetField32(OFFSET_OF_OBJECT_MEMBER(String, count_), false); + DCHECK(result >= 0 && result <= GetCharArray()->GetLength()); + return result; +} + +uint16_t String::CharAt(int32_t index) const { + // TODO: do we need this? Equals is the only caller, and could + // bounds check itself. + if (index < 0 || index >= count_) { + Thread* self = Thread::Current(); + ThrowLocation throw_location = self->GetCurrentLocationForThrow(); + self->ThrowNewExceptionF(throw_location, "Ljava/lang/StringIndexOutOfBoundsException;", + "length=%i; index=%i", count_, index); + return 0; + } + return GetCharArray()->Get(index + GetOffset()); +} + +String* String::AllocFromUtf16(Thread* self, + int32_t utf16_length, + const uint16_t* utf16_data_in, + int32_t hash_code) { + CHECK(utf16_data_in != NULL || utf16_length == 0); + String* string = Alloc(self, GetJavaLangString(), utf16_length); + if (string == NULL) { + return NULL; + } + // TODO: use 16-bit wide memset variant + CharArray* array = const_cast<CharArray*>(string->GetCharArray()); + if (array == NULL) { + return NULL; + } + for (int i = 0; i < utf16_length; i++) { + array->Set(i, utf16_data_in[i]); + } + if (hash_code != 0) { + string->SetHashCode(hash_code); + } else { + string->ComputeHashCode(); + } + return string; +} + + String* String::AllocFromModifiedUtf8(Thread* self, const char* utf) { + if (utf == NULL) { + return NULL; + } + size_t char_count = CountModifiedUtf8Chars(utf); + return AllocFromModifiedUtf8(self, char_count, utf); +} + +String* String::AllocFromModifiedUtf8(Thread* self, int32_t utf16_length, + const char* utf8_data_in) { + String* string = Alloc(self, GetJavaLangString(), utf16_length); + if (string == NULL) { + return NULL; + } + uint16_t* utf16_data_out = + const_cast<uint16_t*>(string->GetCharArray()->GetData()); + ConvertModifiedUtf8ToUtf16(utf16_data_out, utf8_data_in); + string->ComputeHashCode(); + return string; +} + +String* String::Alloc(Thread* self, Class* java_lang_String, int32_t utf16_length) { + SirtRef<CharArray> array(self, CharArray::Alloc(self, utf16_length)); + if (array.get() == NULL) { + return NULL; + } + return Alloc(self, java_lang_String, array.get()); +} + +String* String::Alloc(Thread* self, Class* java_lang_String, CharArray* array) { + // Hold reference in case AllocObject causes GC. + SirtRef<CharArray> array_ref(self, array); + String* string = down_cast<String*>(java_lang_String->AllocObject(self)); + if (string == NULL) { + return NULL; + } + string->SetArray(array); + string->SetCount(array->GetLength()); + return string; +} + +bool String::Equals(const String* that) const { + if (this == that) { + // Quick reference equality test + return true; + } else if (that == NULL) { + // Null isn't an instanceof anything + return false; + } else if (this->GetLength() != that->GetLength()) { + // Quick length inequality test + return false; + } else { + // Note: don't short circuit on hash code as we're presumably here as the + // hash code was already equal + for (int32_t i = 0; i < that->GetLength(); ++i) { + if (this->CharAt(i) != that->CharAt(i)) { + return false; + } + } + return true; + } +} + +bool String::Equals(const uint16_t* that_chars, int32_t that_offset, int32_t that_length) const { + if (this->GetLength() != that_length) { + return false; + } else { + for (int32_t i = 0; i < that_length; ++i) { + if (this->CharAt(i) != that_chars[that_offset + i]) { + return false; + } + } + return true; + } +} + +bool String::Equals(const char* modified_utf8) const { + for (int32_t i = 0; i < GetLength(); ++i) { + uint16_t ch = GetUtf16FromUtf8(&modified_utf8); + if (ch == '\0' || ch != CharAt(i)) { + return false; + } + } + return *modified_utf8 == '\0'; +} + +bool String::Equals(const StringPiece& modified_utf8) const { + if (modified_utf8.size() != GetLength()) { + return false; + } + const char* p = modified_utf8.data(); + for (int32_t i = 0; i < GetLength(); ++i) { + uint16_t ch = GetUtf16FromUtf8(&p); + if (ch != CharAt(i)) { + return false; + } + } + return true; +} + +// Create a modified UTF-8 encoded std::string from a java/lang/String object. +std::string String::ToModifiedUtf8() const { + const uint16_t* chars = GetCharArray()->GetData() + GetOffset(); + size_t byte_count = GetUtfLength(); + std::string result(byte_count, static_cast<char>(0)); + ConvertUtf16ToModifiedUtf8(&result[0], chars, GetLength()); + return result; +} + +#ifdef HAVE__MEMCMP16 +// "count" is in 16-bit units. +extern "C" uint32_t __memcmp16(const uint16_t* s0, const uint16_t* s1, size_t count); +#define MemCmp16 __memcmp16 +#else +static uint32_t MemCmp16(const uint16_t* s0, const uint16_t* s1, size_t count) { + for (size_t i = 0; i < count; i++) { + if (s0[i] != s1[i]) { + return static_cast<int32_t>(s0[i]) - static_cast<int32_t>(s1[i]); + } + } + return 0; +} +#endif + +int32_t String::CompareTo(String* rhs) const { + // Quick test for comparison of a string with itself. + const String* lhs = this; + if (lhs == rhs) { + return 0; + } + // TODO: is this still true? + // The annoying part here is that 0x00e9 - 0xffff != 0x00ea, + // because the interpreter converts the characters to 32-bit integers + // *without* sign extension before it subtracts them (which makes some + // sense since "char" is unsigned). So what we get is the result of + // 0x000000e9 - 0x0000ffff, which is 0xffff00ea. + int lhsCount = lhs->GetLength(); + int rhsCount = rhs->GetLength(); + int countDiff = lhsCount - rhsCount; + int minCount = (countDiff < 0) ? lhsCount : rhsCount; + const uint16_t* lhsChars = lhs->GetCharArray()->GetData() + lhs->GetOffset(); + const uint16_t* rhsChars = rhs->GetCharArray()->GetData() + rhs->GetOffset(); + int otherRes = MemCmp16(lhsChars, rhsChars, minCount); + if (otherRes != 0) { + return otherRes; + } + return countDiff; +} + +} // namespace mirror +} // namespace art + |