/* * Copyright (C) 2018 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. */ #pragma once #include "frameworks/base/cmds/statsd/src/statsd_config.pb.h" namespace android { namespace os { namespace statsd { class HashableDimensionKey; struct Matcher; struct Field; struct FieldValue; const int32_t kAttributionField = 1; const int32_t kMaxLogDepth = 2; const int32_t kLastBitMask = 0x80; const int32_t kClearLastBitDeco = 0x7f; const int32_t kClearAllPositionMatcherMask = 0xffff00ff; enum Type { UNKNOWN, INT, LONG, FLOAT, STRING }; int32_t getEncodedField(int32_t pos[], int32_t depth, bool includeDepth); int32_t encodeMatcherMask(int32_t mask[], int32_t depth); // Get the encoded field for a leaf with a [field] number at depth 0; inline int32_t getSimpleField(size_t field) { return ((int32_t)field << 8 * 2); } /** * Field is a wrapper class for 2 integers that represents the field of a log element in its Atom * proto. * [mTag]: the atom id. * [mField]: encoded path from the root (atom) to leaf. * * For example: * WakeLockStateChanged { * repeated AttributionNode = 1; * int state = 2; * string tag = 3; * } * Read from logd, the items are structured as below: * [[[1000, "tag"], [2000, "tag2"],], 2,"hello"] * * When we read through the list, we will encode each field in a 32bit integer. * 8bit segments |--------|--------|--------|--------| * Depth field0 [L]field1 [L]field1 * * The first 8 bits are the depth of the field. for example, the uid 1000 has depth 2. * The following 3 8-bit are for the item's position at each level. * The first bit of each 8bits field is reserved to mark if the item is the last item at that level * this is to make matching easier later. * * The above wakelock event is translated into FieldValue pairs. * 0x02010101->1000 * 0x02010182->tag * 0x02018201->2000 * 0x02018282->tag2 * 0x00020000->2 * 0x00030000->"hello" * * This encoding is the building block for the later operations. * Please see the definition for Matcher below to see how the matching is done. */ struct Field { private: int32_t mTag; int32_t mField; public: Field() {} Field(int32_t tag, int32_t pos[], int32_t depth) : mTag(tag) { mField = getEncodedField(pos, depth, true); } Field(const Field& from) : mTag(from.getTag()), mField(from.getField()) { } Field(int32_t tag, int32_t field) : mTag(tag), mField(field){}; inline void setField(int32_t field) { mField = field; } inline void setTag(int32_t tag) { mTag = tag; } inline void decorateLastPos(int32_t depth) { int32_t mask = kLastBitMask << 8 * (kMaxLogDepth - depth); mField |= mask; } inline int32_t getTag() const { return mTag; } inline int32_t getDepth() const { return (mField >> 24); } inline int32_t getPath(int32_t depth) const { if (depth > 2 || depth < 0) return 0; int32_t field = (mField & 0x00ffffff); int32_t mask = 0xffffffff; return (field & (mask << 8 * (kMaxLogDepth - depth))); } inline int32_t getPrefix(int32_t depth) const { if (depth == 0) return 0; return getPath(depth - 1); } inline int32_t getField() const { return mField; } inline int32_t getRawPosAtDepth(int32_t depth) const { int32_t field = (mField & 0x00ffffff); int32_t shift = 8 * (kMaxLogDepth - depth); int32_t mask = 0xff << shift; return (field & mask) >> shift; } inline int32_t getPosAtDepth(int32_t depth) const { return getRawPosAtDepth(depth) & kClearLastBitDeco; } // Check if the first bit of the 8-bit segment for depth is 1 inline bool isLastPos(int32_t depth) const { int32_t field = (mField & 0x00ffffff); int32_t mask = kLastBitMask << 8 * (kMaxLogDepth - depth); return (field & mask) != 0; } // if the 8-bit segment is all 0's inline bool isAnyPosMatcher(int32_t depth) const { return getDepth() >= depth && getRawPosAtDepth(depth) == 0; } // if the 8bit is 0x80 (1000 0000) inline bool isLastPosMatcher(int32_t depth) const { return getDepth() >= depth && getRawPosAtDepth(depth) == kLastBitMask; } inline bool operator==(const Field& that) const { return mTag == that.getTag() && mField == that.getField(); }; inline bool operator!=(const Field& that) const { return mTag != that.getTag() || mField != that.getField(); }; bool operator<(const Field& that) const { if (mTag != that.getTag()) { return mTag < that.getTag(); } if (mField != that.getField()) { return mField < that.getField(); } return false; } bool matches(const Matcher& that) const; }; /** * Matcher represents a leaf matcher in the FieldMatcher in statsd_config. * * It contains all information needed to match one or more leaf node. * All information is encoded in a Field(2 ints) and a bit mask(1 int). * * For example, to match the first/any/last uid field in attribution chain in Atom 10, * we have the following FieldMatcher in statsd_config * FieldMatcher { * field:10 * FieldMatcher { * field:1 * position: any/last/first * FieldMatcher { * field:1 * } * } * } * * We translate the FieldMatcher into a Field, and mask * First: [Matcher Field] 0x02010101 [Mask]0xff7f7f7f * Last: [Matcher Field] 0x02018001 [Mask]0xff7f807f * Any: [Matcher Field] 0x02010001 [Mask]0xff7f007f * All: [Matcher Field] 0x02010001 [Mask]0xff7f7f7f * * [To match a log Field with a Matcher] we apply the bit mask to the log Field and check if * the result is equal to the Matcher Field. That's a bit wise AND operation + check if 2 ints are * equal. Nothing can beat the performance of this matching algorithm. * * TODO: ADD EXAMPLE HERE. */ struct Matcher { Matcher(const Field& matcher, int32_t mask) : mMatcher(matcher), mMask(mask){}; const Field mMatcher; const int32_t mMask; inline const Field& getMatcher() const { return mMatcher; } inline int32_t getMask() const { return mMask; } inline int32_t getRawMaskAtDepth(int32_t depth) const { int32_t field = (mMask & 0x00ffffff); int32_t shift = 8 * (kMaxLogDepth - depth); int32_t mask = 0xff << shift; return (field & mask) >> shift; } bool hasAllPositionMatcher() const { return mMatcher.getDepth() == 2 && getRawMaskAtDepth(1) == 0x7f; } bool hasAnyPositionMatcher(int* prefix) const { if (mMatcher.getDepth() == 2 && mMatcher.getRawPosAtDepth(1) == 0) { (*prefix) = mMatcher.getPrefix(1); return true; } return false; } inline bool operator!=(const Matcher& that) const { return mMatcher != that.getMatcher() || mMask != that.getMask(); } inline bool operator==(const Matcher& that) const { return mMatcher == that.mMatcher && mMask == that.mMask; } }; inline Matcher getSimpleMatcher(int32_t tag, size_t field) { return Matcher(Field(tag, getSimpleField(field)), 0xff7f0000); } /** * A wrapper for a union type to contain multiple types of values. * */ struct Value { Value() : type(UNKNOWN) {} Value(int32_t v) { int_value = v; type = INT; } Value(int64_t v) { long_value = v; type = LONG; } Value(float v) { float_value = v; type = FLOAT; } Value(const std::string& v) { str_value = v; type = STRING; } void setInt(int32_t v) { int_value = v; type = INT; } void setLong(int64_t v) { long_value = v; type = LONG; } union { int32_t int_value; int64_t long_value; float float_value; }; std::string str_value; Type type; std::string toString() const; Type getType() const { return type; } Value(const Value& from); bool operator==(const Value& that) const; bool operator!=(const Value& that) const; bool operator<(const Value& that) const; }; /** * Represents a log item, or a dimension item (They are essentially the same). */ struct FieldValue { FieldValue() {} FieldValue(const Field& field, const Value& value) : mField(field), mValue(value) { } bool operator==(const FieldValue& that) const { return mField == that.mField && mValue == that.mValue; } bool operator!=(const FieldValue& that) const { return mField != that.mField || mValue != that.mValue; } bool operator<(const FieldValue& that) const { if (mField != that.mField) { return mField < that.mField; } if (mValue != that.mValue) { return mValue < that.mValue; } return false; } Field mField; Value mValue; }; bool HasPositionANY(const FieldMatcher& matcher); bool HasPositionALL(const FieldMatcher& matcher); bool isAttributionUidField(const FieldValue& value); void translateFieldMatcher(const FieldMatcher& matcher, std::vector<Matcher>* output); bool isAttributionUidField(const Field& field, const Value& value); bool equalDimensions(const std::vector<Matcher>& dimension_a, const std::vector<Matcher>& dimension_b); } // namespace statsd } // namespace os } // namespace android