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Diffstat (limited to 'dom/indexedDB/Key.cpp')
| -rw-r--r-- | dom/indexedDB/Key.cpp | 969 |
1 files changed, 969 insertions, 0 deletions
diff --git a/dom/indexedDB/Key.cpp b/dom/indexedDB/Key.cpp new file mode 100644 index 0000000000..6f96023a54 --- /dev/null +++ b/dom/indexedDB/Key.cpp @@ -0,0 +1,969 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "Key.h" + +#include <algorithm> +#include <cstdint> +#include <stdint.h> // for UINT32_MAX, uintptr_t +#include "js/Array.h" // JS::NewArrayObject +#include "js/ArrayBuffer.h" // JS::{IsArrayBufferObject,NewArrayBuffer{,WithContents},GetArrayBufferLengthAndData} +#include "js/Date.h" +#include "js/experimental/TypedData.h" // JS_IsArrayBufferViewObject, JS_GetObjectAsArrayBufferView +#include "js/MemoryFunctions.h" +#include "js/Object.h" // JS::GetBuiltinClass +#include "js/PropertyAndElement.h" // JS_DefineElement, JS_GetProperty, JS_GetPropertyById, JS_HasOwnProperty, JS_HasOwnPropertyById +#include "js/Value.h" +#include "jsfriendapi.h" +#include "mozilla/Casting.h" +#include "mozilla/CheckedInt.h" +#include "mozilla/EndianUtils.h" +#include "mozilla/FloatingPoint.h" +#include "mozilla/intl/Collator.h" +#include "mozilla/ResultExtensions.h" +#include "mozilla/ReverseIterator.h" +#include "mozilla/dom/indexedDB/IDBResult.h" +#include "mozilla/dom/indexedDB/Key.h" +#include "mozilla/dom/quota/QuotaCommon.h" +#include "mozilla/dom/quota/ResultExtensions.h" +#include "mozIStorageStatement.h" +#include "mozIStorageValueArray.h" +#include "nsJSUtils.h" +#include "nsTStringRepr.h" +#include "ReportInternalError.h" +#include "xpcpublic.h" + +namespace mozilla::dom::indexedDB { + +namespace { +// Implementation of the array branch of step 3 of +// https://w3c.github.io/IndexedDB/#convert-value-to-key +template <typename ArrayConversionPolicy> +IDBResult<Ok, IDBSpecialValue::Invalid> ConvertArrayValueToKey( + JSContext* const aCx, JS::Handle<JSObject*> aObject, + ArrayConversionPolicy&& aPolicy) { + // 1. Let `len` be ? ToLength( ? Get(`input`, "length")). + uint32_t len; + if (!JS::GetArrayLength(aCx, aObject, &len)) { + return Err(IDBException(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR)); + } + + // 2. Add `input` to `seen`. + aPolicy.AddToSeenSet(aCx, aObject); + + // 3. Let `keys` be a new empty list. + aPolicy.BeginSubkeyList(); + + // 4. Let `index` be 0. + uint32_t index = 0; + + // 5. While `index` is less than `len`: + while (index < len) { + JS::Rooted<JS::PropertyKey> indexId(aCx); + if (!JS_IndexToId(aCx, index, &indexId)) { + return Err(IDBException(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR)); + } + + // 1. Let `hop` be ? HasOwnProperty(`input`, `index`). + bool hop; + if (!JS_HasOwnPropertyById(aCx, aObject, indexId, &hop)) { + return Err(IDBException(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR)); + } + + // 2. If `hop` is false, return invalid. + if (!hop) { + return Err(IDBError(SpecialValues::Invalid)); + } + + // 3. Let `entry` be ? Get(`input`, `index`). + JS::Rooted<JS::Value> entry(aCx); + if (!JS_GetPropertyById(aCx, aObject, indexId, &entry)) { + return Err(IDBException(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR)); + } + + // 4. Let `key` be the result of running the steps to convert a value to a + // key with arguments `entry` and `seen`. + // 5. ReturnIfAbrupt(`key`). + // 6. If `key` is invalid abort these steps and return invalid. + // 7. Append `key` to `keys`. + auto result = aPolicy.ConvertSubkey(aCx, entry, index); + if (result.isErr()) { + return result; + } + + // 8. Increase `index` by 1. + index += 1; + } + + // 6. Return a new array key with value `keys`. + aPolicy.EndSubkeyList(); + return Ok(); +} +} // namespace + +/* + Here's how we encode keys: + + Basic strategy is the following + + Numbers: 0x10 n n n n n n n n ("n"s are encoded 64bit float) + Dates: 0x20 n n n n n n n n ("n"s are encoded 64bit float) + Strings: 0x30 s s s ... 0 ("s"s are encoded unicode bytes) + Binaries: 0x40 s s s ... 0 ("s"s are encoded unicode bytes) + Arrays: 0x50 i i i ... 0 ("i"s are encoded array items) + + + When encoding floats, 64bit IEEE 754 are almost sortable, except that + positive sort lower than negative, and negative sort descending. So we use + the following encoding: + + value < 0 ? + (-to64bitInt(value)) : + (to64bitInt(value) | 0x8000000000000000) + + + When encoding strings, we use variable-size encoding per the following table + + Chars 0 - 7E are encoded as 0xxxxxxx with 1 added + Chars 7F - (3FFF+7F) are encoded as 10xxxxxx xxxxxxxx with 7F + subtracted + Chars (3FFF+80) - FFFF are encoded as 11xxxxxx xxxxxxxx xx000000 + + This ensures that the first byte is never encoded as 0, which means that the + string terminator (per basic-strategy table) sorts before any character. + The reason that (3FFF+80) - FFFF is encoded "shifted up" 6 bits is to maximize + the chance that the last character is 0. See below for why. + + When encoding binaries, the algorithm is the same to how strings are encoded. + Since each octet in binary is in the range of [0-255], it'll take 1 to 2 + encoded unicode bytes. + + When encoding Arrays, we use an additional trick. Rather than adding a byte + containing the value 0x50 to indicate type, we instead add 0x50 to the next + byte. This is usually the byte containing the type of the first item in the + array. So simple examples are + + ["foo"] 0x80 s s s 0 0 // 0x80 is 0x30 + 0x50 + [1, 2] 0x60 n n n n n n n n 1 n n n n n n n n 0 // 0x60 is 0x10 + 0x50 + + Whe do this iteratively if the first item in the array is also an array + + [["foo"]] 0xA0 s s s 0 0 0 + + However, to avoid overflow in the byte, we only do this 3 times. If the first + item in an array is an array, and that array also has an array as first item, + we simply write out the total value accumulated so far and then follow the + "normal" rules. + + [[["foo"]]] 0xF0 0x30 s s s 0 0 0 0 + + There is another edge case that can happen though, which is that the array + doesn't have a first item to which we can add 0x50 to the type. Instead the + next byte would normally be the array terminator (per basic-strategy table) + so we simply add the 0x50 there. + + [[]] 0xA0 0 // 0xA0 is 0x50 + 0x50 + 0 + [] 0x50 // 0x50 is 0x50 + 0 + [[], "foo"] 0xA0 0x30 s s s 0 0 // 0xA0 is 0x50 + 0x50 + 0 + + Note that the max-3-times rule kicks in before we get a chance to add to the + array terminator + + [[[]]] 0xF0 0 0 0 // 0xF0 is 0x50 + 0x50 + 0x50 + + As a final optimization we do a post-encoding step which drops all 0s at the + end of the encoded buffer. + + "foo" // 0x30 s s s + 1 // 0x10 bf f0 + ["a", "b"] // 0x80 s 0 0x30 s + [1, 2] // 0x60 bf f0 0 0 0 0 0 0 0x10 c0 + [[]] // 0x80 +*/ + +Result<Ok, nsresult> Key::SetFromString(const nsAString& aString) { + mBuffer.Truncate(); + auto result = EncodeString(aString, 0); + if (result.isOk()) { + TrimBuffer(); + } + return result; +} + +// |aPos| should point to the type indicator. +// The returned length doesn't include the type indicator +// or the terminator. +// static +uint32_t Key::LengthOfEncodedBinary(const EncodedDataType* aPos, + const EncodedDataType* aEnd) { + MOZ_ASSERT(*aPos % Key::eMaxType == Key::eBinary, "Don't call me!"); + + const auto* iter = aPos + 1; + for (; iter < aEnd && *iter != eTerminator; ++iter) { + if (*iter & 0x80) { + ++iter; + // XXX if iter == aEnd now, we got a bad enconding, should we report that + // also in non-debug builds? + MOZ_ASSERT(iter < aEnd); + } + } + + return iter - aPos - 1; +} + +Result<Key, nsresult> Key::ToLocaleAwareKey(const nsCString& aLocale) const { + Key res; + + if (IsUnset()) { + return res; + } + + if (IsFloat() || IsDate() || IsBinary()) { + res.mBuffer = mBuffer; + return res; + } + + auto* it = BufferStart(); + auto* const end = BufferEnd(); + + // First we do a pass and see if there are any strings in this key. We only + // want to copy/decode when necessary. + bool canShareBuffers = true; + while (it < end) { + const auto type = *it % eMaxType; + if (type == eTerminator) { + it++; + } else if (type == eFloat || type == eDate) { + it++; + it += std::min(sizeof(uint64_t), size_t(end - it)); + } else if (type == eBinary) { + // skip all binary data + const auto binaryLength = LengthOfEncodedBinary(it, end); + it++; + it += binaryLength; + } else { + // We have a string! + canShareBuffers = false; + break; + } + } + + if (canShareBuffers) { + MOZ_ASSERT(it == end); + res.mBuffer = mBuffer; + return res; + } + + if (!res.mBuffer.SetCapacity(mBuffer.Length(), fallible)) { + return Err(NS_ERROR_OUT_OF_MEMORY); + } + + // A string was found, so we need to copy the data we've read so far + auto* const start = BufferStart(); + if (it > start) { + char* buffer; + MOZ_ALWAYS_TRUE(res.mBuffer.GetMutableData(&buffer, it - start)); + std::copy(start, it, buffer); + } + + // Now continue decoding + while (it < end) { + char* buffer; + const size_t oldLen = res.mBuffer.Length(); + const auto type = *it % eMaxType; + + // Note: Do not modify |it| before calling |updateBufferAndIter|; + // |byteCount| doesn't include the type indicator + const auto updateBufferAndIter = [&](size_t byteCount) -> bool { + if (!res.mBuffer.GetMutableData(&buffer, oldLen + 1 + byteCount)) { + return false; + } + buffer += oldLen; + + // should also copy the type indicator at the begining + std::copy_n(it, byteCount + 1, buffer); + it += (byteCount + 1); + return true; + }; + + if (type == eTerminator) { + // Copy array TypeID and terminator from raw key + if (!updateBufferAndIter(0)) { + return Err(NS_ERROR_OUT_OF_MEMORY); + } + } else if (type == eFloat || type == eDate) { + // Copy number from raw key + const size_t byteCount = std::min(sizeof(uint64_t), size_t(end - it - 1)); + + if (!updateBufferAndIter(byteCount)) { + return Err(NS_ERROR_OUT_OF_MEMORY); + } + } else if (type == eBinary) { + // skip all binary data + const auto binaryLength = LengthOfEncodedBinary(it, end); + + if (!updateBufferAndIter(binaryLength)) { + return Err(NS_ERROR_OUT_OF_MEMORY); + } + } else { + // Decode string and reencode + const uint8_t typeOffset = *it - eString; + MOZ_ASSERT((typeOffset % eArray == 0) && (typeOffset / eArray <= 2)); + + auto str = DecodeString(it, end); + auto result = res.EncodeLocaleString(str, typeOffset, aLocale); + if (NS_WARN_IF(result.isErr())) { + return result.propagateErr(); + } + } + } + res.TrimBuffer(); + return res; +} + +class MOZ_STACK_CLASS Key::ArrayValueEncoder final { + public: + ArrayValueEncoder(Key& aKey, const uint8_t aTypeOffset, + const uint16_t aRecursionDepth) + : mKey(aKey), + mTypeOffset(aTypeOffset), + mRecursionDepth(aRecursionDepth) {} + + void AddToSeenSet(JSContext* const aCx, JS::Handle<JSObject*>) { + ++mRecursionDepth; + } + + void BeginSubkeyList() { + mTypeOffset += Key::eMaxType; + if (mTypeOffset == eMaxType * kMaxArrayCollapse) { + mKey.mBuffer.Append(mTypeOffset); + mTypeOffset = 0; + } + MOZ_ASSERT(mTypeOffset % eMaxType == 0, + "Current type offset must indicate beginning of array"); + MOZ_ASSERT(mTypeOffset < eMaxType * kMaxArrayCollapse); + } + + IDBResult<Ok, IDBSpecialValue::Invalid> ConvertSubkey( + JSContext* const aCx, JS::Handle<JS::Value> aEntry, + const uint32_t aIndex) { + auto result = + mKey.EncodeJSValInternal(aCx, aEntry, mTypeOffset, mRecursionDepth); + mTypeOffset = 0; + return result; + } + + void EndSubkeyList() const { mKey.mBuffer.Append(eTerminator + mTypeOffset); } + + private: + Key& mKey; + uint8_t mTypeOffset; + uint16_t mRecursionDepth; +}; + +// Implements the following algorithm: +// https://w3c.github.io/IndexedDB/#convert-a-value-to-a-key +IDBResult<Ok, IDBSpecialValue::Invalid> Key::EncodeJSValInternal( + JSContext* const aCx, JS::Handle<JS::Value> aVal, uint8_t aTypeOffset, + const uint16_t aRecursionDepth) { + static_assert(eMaxType * kMaxArrayCollapse < 256, "Unable to encode jsvals."); + + // 1. If `seen` was not given, let `seen` be a new empty set. + // 2. If `input` is in `seen` return invalid. + // Note: we replace this check with a simple recursion depth check. + if (NS_WARN_IF(aRecursionDepth == kMaxRecursionDepth)) { + return Err(IDBError(SpecialValues::Invalid)); + } + + // 3. Jump to the appropriate step below: + // Note: some cases appear out of order to make the implementation more + // straightforward. This shouldn't affect observable behavior. + + // If Type(`input`) is Number + if (aVal.isNumber()) { + const auto number = aVal.toNumber(); + + // 1. If `input` is NaN then return invalid. + if (std::isnan(number)) { + return Err(IDBError(SpecialValues::Invalid)); + } + + // 2. Otherwise, return a new key with type `number` and value `input`. + return EncodeNumber(number, eFloat + aTypeOffset); + } + + // If Type(`input`) is String + if (aVal.isString()) { + // 1. Return a new key with type `string` and value `input`. + nsAutoJSString string; + if (!string.init(aCx, aVal)) { + IDB_REPORT_INTERNAL_ERR(); + return Err(IDBException(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR)); + } + return EncodeString(string, aTypeOffset); + } + + if (aVal.isObject()) { + JS::Rooted<JSObject*> object(aCx, &aVal.toObject()); + + js::ESClass builtinClass; + if (!JS::GetBuiltinClass(aCx, object, &builtinClass)) { + IDB_REPORT_INTERNAL_ERR(); + return Err(IDBException(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR)); + } + + // If `input` is a Date (has a [[DateValue]] internal slot) + if (builtinClass == js::ESClass::Date) { + // 1. Let `ms` be the value of `input`’s [[DateValue]] internal slot. + double ms; + if (!js::DateGetMsecSinceEpoch(aCx, object, &ms)) { + IDB_REPORT_INTERNAL_ERR(); + return Err(IDBException(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR)); + } + + // 2. If `ms` is NaN then return invalid. + if (std::isnan(ms)) { + return Err(IDBError(SpecialValues::Invalid)); + } + + // 3. Otherwise, return a new key with type `date` and value `ms`. + return EncodeNumber(ms, eDate + aTypeOffset); + } + + // If `input` is a buffer source type + if (JS::IsArrayBufferObject(object) || JS_IsArrayBufferViewObject(object)) { + const bool isViewObject = JS_IsArrayBufferViewObject(object); + return EncodeBinary(object, isViewObject, aTypeOffset); + } + + // If IsArray(`input`) + if (builtinClass == js::ESClass::Array) { + return ConvertArrayValueToKey( + aCx, object, ArrayValueEncoder{*this, aTypeOffset, aRecursionDepth}); + } + } + + // Otherwise + // Return invalid. + return Err(IDBError(SpecialValues::Invalid)); +} + +// static +nsresult Key::DecodeJSValInternal(const EncodedDataType*& aPos, + const EncodedDataType* aEnd, JSContext* aCx, + uint8_t aTypeOffset, + JS::MutableHandle<JS::Value> aVal, + uint16_t aRecursionDepth) { + if (NS_WARN_IF(aRecursionDepth == kMaxRecursionDepth)) { + return NS_ERROR_DOM_INDEXEDDB_DATA_ERR; + } + + if (*aPos - aTypeOffset >= eArray) { + JS::Rooted<JSObject*> array(aCx, JS::NewArrayObject(aCx, 0)); + if (!array) { + NS_WARNING("Failed to make array!"); + IDB_REPORT_INTERNAL_ERR(); + return NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR; + } + + aTypeOffset += eMaxType; + + if (aTypeOffset == eMaxType * kMaxArrayCollapse) { + ++aPos; + aTypeOffset = 0; + } + + uint32_t index = 0; + JS::Rooted<JS::Value> val(aCx); + while (aPos < aEnd && *aPos - aTypeOffset != eTerminator) { + QM_TRY(MOZ_TO_RESULT(DecodeJSValInternal(aPos, aEnd, aCx, aTypeOffset, + &val, aRecursionDepth + 1))); + + aTypeOffset = 0; + + if (!JS_DefineElement(aCx, array, index++, val, JSPROP_ENUMERATE)) { + NS_WARNING("Failed to set array element!"); + IDB_REPORT_INTERNAL_ERR(); + return NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR; + } + } + + NS_ASSERTION(aPos >= aEnd || (*aPos % eMaxType) == eTerminator, + "Should have found end-of-array marker"); + ++aPos; + + aVal.setObject(*array); + } else if (*aPos - aTypeOffset == eString) { + auto key = DecodeString(aPos, aEnd); + if (!xpc::StringToJsval(aCx, key, aVal)) { + IDB_REPORT_INTERNAL_ERR(); + return NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR; + } + } else if (*aPos - aTypeOffset == eDate) { + double msec = static_cast<double>(DecodeNumber(aPos, aEnd)); + JS::ClippedTime time = JS::TimeClip(msec); + MOZ_ASSERT(msec == time.toDouble(), + "encoding from a Date object not containing an invalid date " + "means we should always have clipped values"); + JSObject* date = JS::NewDateObject(aCx, time); + if (!date) { + IDB_WARNING("Failed to make date!"); + return NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR; + } + + aVal.setObject(*date); + } else if (*aPos - aTypeOffset == eFloat) { + aVal.setDouble(DecodeNumber(aPos, aEnd)); + } else if (*aPos - aTypeOffset == eBinary) { + JSObject* binary = DecodeBinary(aPos, aEnd, aCx); + if (!binary) { + IDB_REPORT_INTERNAL_ERR(); + return NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR; + } + + aVal.setObject(*binary); + } else { + MOZ_ASSERT_UNREACHABLE("Unknown key type!"); + } + + return NS_OK; +} + +#define ONE_BYTE_LIMIT 0x7E +#define TWO_BYTE_LIMIT (0x3FFF + 0x7F) + +#define ONE_BYTE_ADJUST 1 +#define TWO_BYTE_ADJUST (-0x7F) +#define THREE_BYTE_SHIFT 6 + +IDBResult<Ok, IDBSpecialValue::Invalid> Key::EncodeJSVal( + JSContext* aCx, JS::Handle<JS::Value> aVal, uint8_t aTypeOffset) { + return EncodeJSValInternal(aCx, aVal, aTypeOffset, 0); +} + +Result<Ok, nsresult> Key::EncodeString(const nsAString& aString, + uint8_t aTypeOffset) { + return EncodeString(Span{aString}, aTypeOffset); +} + +template <typename T> +Result<Ok, nsresult> Key::EncodeString(const Span<const T> aInput, + uint8_t aTypeOffset) { + return EncodeAsString(aInput, eString + aTypeOffset); +} + +// nsCString maximum length is limited by INT32_MAX. +// XXX: We probably want to enforce even shorter keys, though. +#define KEY_MAXIMUM_BUFFER_LENGTH \ + ::mozilla::detail::nsTStringLengthStorage<char>::kMax + +template <typename T> +Result<Ok, nsresult> Key::EncodeAsString(const Span<const T> aInput, + uint8_t aType) { + // Please note that the input buffer can either be based on two-byte UTF-16 + // values or on arbitrary single byte binary values. Only the first case + // needs to account for the TWO_BYTE_LIMIT of UTF-8. + // First we measure how long the encoded string will be. + + // The 2 is for initial aType and trailing 0. We'll compensate for multi-byte + // chars below. + size_t size = 2; + + // We construct a range over the raw pointers here because this loop is + // time-critical. + // XXX It might be good to encapsulate this in some function to make it less + // error-prone and more expressive. + const auto inputRange = mozilla::detail::IteratorRange( + aInput.Elements(), aInput.Elements() + aInput.Length()); + + size_t payloadSize = aInput.Length(); + bool anyMultibyte = false; + for (const T val : inputRange) { + if (val > ONE_BYTE_LIMIT) { + anyMultibyte = true; + payloadSize += char16_t(val) > TWO_BYTE_LIMIT ? 2 : 1; + if (payloadSize > KEY_MAXIMUM_BUFFER_LENGTH) { + return Err(NS_ERROR_DOM_INDEXEDDB_KEY_ERR); + } + } + } + + size += payloadSize; + + // Now we allocate memory for the new size + size_t oldLen = mBuffer.Length(); + size += oldLen; + + if (size > KEY_MAXIMUM_BUFFER_LENGTH) { + return Err(NS_ERROR_DOM_INDEXEDDB_KEY_ERR); + } + + char* buffer; + if (!mBuffer.GetMutableData(&buffer, size)) { + IDB_REPORT_INTERNAL_ERR(); + return Err(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR); + } + buffer += oldLen; + + // Write type marker + *(buffer++) = aType; + + // Encode string + if (anyMultibyte) { + for (const auto val : inputRange) { + if (val <= ONE_BYTE_LIMIT) { + *(buffer++) = val + ONE_BYTE_ADJUST; + } else if (char16_t(val) <= TWO_BYTE_LIMIT) { + char16_t c = char16_t(val) + TWO_BYTE_ADJUST + 0x8000; + *(buffer++) = (char)(c >> 8); + *(buffer++) = (char)(c & 0xFF); + } else { + uint32_t c = (uint32_t(val) << THREE_BYTE_SHIFT) | 0x00C00000; + *(buffer++) = (char)(c >> 16); + *(buffer++) = (char)(c >> 8); + *(buffer++) = (char)c; + } + } + } else { + // Optimization for the case where there are no multibyte characters. + // This is ca. 13 resp. 5.8 times faster than the non-optimized version in + // an -O2 build: https://quick-bench.com/q/v1oBpLGifs-3w_pkZG8alVSWVAw, for + // the T==uint8_t resp. T==char16_t cases (for the char16_t case, copying + // and then adjusting could even be slightly faster, but then we would need + // another case distinction here) + size_t inputLen = std::distance(inputRange.cbegin(), inputRange.cend()); + MOZ_ASSERT(inputLen == payloadSize); + std::transform(inputRange.cbegin(), inputRange.cend(), buffer, + [](auto value) { return value + ONE_BYTE_ADJUST; }); + buffer += inputLen; + } + + // Write end marker + *(buffer++) = eTerminator; + + NS_ASSERTION(buffer == mBuffer.EndReading(), "Wrote wrong number of bytes"); + + return Ok(); +} + +Result<Ok, nsresult> Key::EncodeLocaleString(const nsAString& aString, + uint8_t aTypeOffset, + const nsCString& aLocale) { + const int length = aString.Length(); + if (length == 0) { + return Ok(); + } + + auto collResult = intl::Collator::TryCreate(aLocale.get()); + if (collResult.isErr()) { + return Err(NS_ERROR_FAILURE); + } + auto collator = collResult.unwrap(); + MOZ_ASSERT(collator); + + AutoTArray<uint8_t, 128> keyBuffer; + MOZ_TRY(collator->GetSortKey(Span{aString}, keyBuffer) + .mapErr([](intl::ICUError icuError) { + return icuError == intl::ICUError::OutOfMemory + ? NS_ERROR_OUT_OF_MEMORY + : NS_ERROR_FAILURE; + })); + + size_t sortKeyLength = keyBuffer.Length(); + return EncodeString(Span{keyBuffer}.AsConst().First(sortKeyLength), + aTypeOffset); +} + +// static +nsresult Key::DecodeJSVal(const EncodedDataType*& aPos, + const EncodedDataType* aEnd, JSContext* aCx, + JS::MutableHandle<JS::Value> aVal) { + return DecodeJSValInternal(aPos, aEnd, aCx, 0, aVal, 0); +} + +// static +template <typename T> +uint32_t Key::CalcDecodedStringySize( + const EncodedDataType* const aBegin, const EncodedDataType* const aEnd, + const EncodedDataType** aOutEncodedSectionEnd) { + static_assert(sizeof(T) <= 2, + "Only implemented for 1 and 2 byte decoded types"); + uint32_t decodedSize = 0; + auto* iter = aBegin; + for (; iter < aEnd && *iter != eTerminator; ++iter) { + if (*iter & 0x80) { + iter += (sizeof(T) > 1 && (*iter & 0x40)) ? 2 : 1; + } + ++decodedSize; + } + *aOutEncodedSectionEnd = std::min(aEnd, iter); + return decodedSize; +} + +// static +template <typename T> +void Key::DecodeAsStringy(const EncodedDataType* const aEncodedSectionBegin, + const EncodedDataType* const aEncodedSectionEnd, + const uint32_t aDecodedLength, T* const aOut) { + static_assert(sizeof(T) <= 2, + "Only implemented for 1 and 2 byte decoded types"); + T* decodedPos = aOut; + for (const EncodedDataType* iter = aEncodedSectionBegin; + iter < aEncodedSectionEnd;) { + if (!(*iter & 0x80)) { + *decodedPos = *(iter++) - ONE_BYTE_ADJUST; + } else if (sizeof(T) == 1 || !(*iter & 0x40)) { + auto c = static_cast<uint16_t>(*(iter++)) << 8; + if (iter < aEncodedSectionEnd) { + c |= *(iter++); + } + *decodedPos = static_cast<T>(c - TWO_BYTE_ADJUST - 0x8000); + } else if (sizeof(T) > 1) { + auto c = static_cast<uint32_t>(*(iter++)) << (16 - THREE_BYTE_SHIFT); + if (iter < aEncodedSectionEnd) { + c |= static_cast<uint32_t>(*(iter++)) << (8 - THREE_BYTE_SHIFT); + } + if (iter < aEncodedSectionEnd) { + c |= *(iter++) >> THREE_BYTE_SHIFT; + } + *decodedPos = static_cast<T>(c); + } + ++decodedPos; + } + + MOZ_ASSERT(static_cast<uint32_t>(decodedPos - aOut) == aDecodedLength, + "Should have written the whole decoded area"); +} + +// static +template <Key::EncodedDataType TypeMask, typename T, typename AcquireBuffer, + typename AcquireEmpty> +void Key::DecodeStringy(const EncodedDataType*& aPos, + const EncodedDataType* aEnd, + const AcquireBuffer& acquireBuffer, + const AcquireEmpty& acquireEmpty) { + NS_ASSERTION(*aPos % eMaxType == TypeMask, "Don't call me!"); + + // First measure how big the decoded stringy data will be. + const EncodedDataType* const encodedSectionBegin = aPos + 1; + const EncodedDataType* encodedSectionEnd; + // decodedLength does not include the terminating 0 (in case of a string) + const uint32_t decodedLength = + CalcDecodedStringySize<T>(encodedSectionBegin, aEnd, &encodedSectionEnd); + aPos = encodedSectionEnd + 1; + + if (!decodedLength) { + acquireEmpty(); + return; + } + + T* out; + if (!acquireBuffer(&out, decodedLength)) { + return; + } + + DecodeAsStringy(encodedSectionBegin, encodedSectionEnd, decodedLength, out); +} + +// static +nsAutoString Key::DecodeString(const EncodedDataType*& aPos, + const EncodedDataType* const aEnd) { + nsAutoString res; + DecodeStringy<eString, char16_t>( + aPos, aEnd, + [&res](char16_t** out, uint32_t decodedLength) { + return 0 != res.GetMutableData(out, decodedLength); + }, + [] {}); + return res; +} + +Result<Ok, nsresult> Key::EncodeNumber(double aFloat, uint8_t aType) { + // Allocate memory for the new size + size_t oldLen = mBuffer.Length(); + size_t newLen = oldLen + 1 + sizeof(double); + if (newLen > KEY_MAXIMUM_BUFFER_LENGTH) { + return Err(NS_ERROR_DOM_INDEXEDDB_KEY_ERR); + } + + char* buffer; + if (!mBuffer.GetMutableData(&buffer, newLen)) { + return Err(NS_ERROR_DOM_INDEXEDDB_KEY_ERR); + } + buffer += oldLen; + + *(buffer++) = aType; + + uint64_t bits = BitwiseCast<uint64_t>(aFloat); + // Note: The subtraction from 0 below is necessary to fix + // MSVC build warning C4146 (negating an unsigned value). + const uint64_t signbit = FloatingPoint<double>::kSignBit; + uint64_t number = bits & signbit ? (0 - bits) : (bits | signbit); + + mozilla::BigEndian::writeUint64(buffer, number); + return Ok(); +} + +// static +double Key::DecodeNumber(const EncodedDataType*& aPos, + const EncodedDataType* aEnd) { + NS_ASSERTION(*aPos % eMaxType == eFloat || *aPos % eMaxType == eDate, + "Don't call me!"); + + ++aPos; + + uint64_t number = 0; + memcpy(&number, aPos, std::min<size_t>(sizeof(number), aEnd - aPos)); + number = mozilla::NativeEndian::swapFromBigEndian(number); + + aPos += sizeof(number); + + // Note: The subtraction from 0 below is necessary to fix + // MSVC build warning C4146 (negating an unsigned value). + const uint64_t signbit = FloatingPoint<double>::kSignBit; + uint64_t bits = number & signbit ? (number & ~signbit) : (0 - number); + + return BitwiseCast<double>(bits); +} + +Result<Ok, nsresult> Key::EncodeBinary(JSObject* aObject, bool aIsViewObject, + uint8_t aTypeOffset) { + uint8_t* bufferData; + size_t bufferLength; + + // We must use JS::GetObjectAsArrayBuffer()/JS_GetObjectAsArrayBufferView() + // instead of js::GetArrayBufferLengthAndData(). The object might be wrapped, + // the former will handle the wrapped case, the later won't. + if (aIsViewObject) { + bool unused; + JS_GetObjectAsArrayBufferView(aObject, &bufferLength, &unused, &bufferData); + } else { + JS::GetObjectAsArrayBuffer(aObject, &bufferLength, &bufferData); + } + + return EncodeAsString(Span{bufferData, bufferLength}.AsConst(), + eBinary + aTypeOffset); +} + +// static +JSObject* Key::DecodeBinary(const EncodedDataType*& aPos, + const EncodedDataType* aEnd, JSContext* aCx) { + JS::Rooted<JSObject*> rv(aCx); + DecodeStringy<eBinary, uint8_t>( + aPos, aEnd, + [&rv, aCx](uint8_t** out, uint32_t decodedSize) { + UniquePtr<void, JS::FreePolicy> ptr{JS_malloc(aCx, decodedSize)}; + if (NS_WARN_IF(!ptr)) { + *out = nullptr; + rv = nullptr; + return false; + } + + *out = static_cast<uint8_t*>(ptr.get()); + rv = JS::NewArrayBufferWithContents(aCx, decodedSize, std::move(ptr)); + if (NS_WARN_IF(!rv)) { + *out = nullptr; + return false; + } + return true; + }, + [&rv, aCx] { rv = JS::NewArrayBuffer(aCx, 0); }); + return rv; +} + +nsresult Key::BindToStatement(mozIStorageStatement* aStatement, + const nsACString& aParamName) const { + nsresult rv; + if (IsUnset()) { + rv = aStatement->BindNullByName(aParamName); + } else { + rv = aStatement->BindBlobByName( + aParamName, reinterpret_cast<const uint8_t*>(mBuffer.get()), + mBuffer.Length()); + } + + return NS_SUCCEEDED(rv) ? NS_OK : NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR; +} + +nsresult Key::SetFromStatement(mozIStorageStatement* aStatement, + uint32_t aIndex) { + return SetFromSource(aStatement, aIndex); +} + +nsresult Key::SetFromValueArray(mozIStorageValueArray* aValues, + uint32_t aIndex) { + return SetFromSource(aValues, aIndex); +} + +IDBResult<Ok, IDBSpecialValue::Invalid> Key::SetFromJSVal( + JSContext* aCx, JS::Handle<JS::Value> aVal) { + mBuffer.Truncate(); + + if (aVal.isNull() || aVal.isUndefined()) { + Unset(); + return Ok(); + } + + auto result = EncodeJSVal(aCx, aVal, 0); + if (result.isErr()) { + Unset(); + return result; + } + TrimBuffer(); + return Ok(); +} + +nsresult Key::ToJSVal(JSContext* aCx, JS::MutableHandle<JS::Value> aVal) const { + if (IsUnset()) { + aVal.setUndefined(); + return NS_OK; + } + + const EncodedDataType* pos = BufferStart(); + nsresult rv = DecodeJSVal(pos, BufferEnd(), aCx, aVal); + if (NS_WARN_IF(NS_FAILED(rv))) { + return rv; + } + + MOZ_ASSERT(pos >= BufferEnd()); + + return NS_OK; +} + +nsresult Key::ToJSVal(JSContext* aCx, JS::Heap<JS::Value>& aVal) const { + JS::Rooted<JS::Value> value(aCx); + nsresult rv = ToJSVal(aCx, &value); + if (NS_SUCCEEDED(rv)) { + aVal = value; + } + return rv; +} + +IDBResult<Ok, IDBSpecialValue::Invalid> Key::AppendItem( + JSContext* aCx, bool aFirstOfArray, JS::Handle<JS::Value> aVal) { + auto result = EncodeJSVal(aCx, aVal, aFirstOfArray ? eMaxType : 0); + if (result.isErr()) { + Unset(); + } + return result; +} + +template <typename T> +nsresult Key::SetFromSource(T* aSource, uint32_t aIndex) { + const uint8_t* data; + uint32_t dataLength = 0; + + nsresult rv = aSource->GetSharedBlob(aIndex, &dataLength, &data); + if (NS_WARN_IF(NS_FAILED(rv))) { + return NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR; + } + + mBuffer.Assign(reinterpret_cast<const char*>(data), dataLength); + + return NS_OK; +} + +} // namespace mozilla::dom::indexedDB |