| /* |
| * Copyright (C) 2020 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. |
| */ |
| |
| #ifndef SRC_TRACE_PROCESSOR_IMPORTERS_PROTO_PROTO_TRACE_TOKENIZER_H_ |
| #define SRC_TRACE_PROCESSOR_IMPORTERS_PROTO_PROTO_TRACE_TOKENIZER_H_ |
| |
| #include <cstdint> |
| #include <vector> |
| |
| #include "perfetto/base/status.h" |
| #include "perfetto/protozero/proto_utils.h" |
| #include "perfetto/public/compiler.h" |
| #include "perfetto/trace_processor/status.h" |
| #include "perfetto/trace_processor/trace_blob.h" |
| #include "perfetto/trace_processor/trace_blob_view.h" |
| #include "src/trace_processor/util/gzip_utils.h" |
| #include "src/trace_processor/util/status_macros.h" |
| |
| #include "protos/perfetto/trace/trace.pbzero.h" |
| #include "protos/perfetto/trace/trace_packet.pbzero.h" |
| |
| namespace perfetto { |
| namespace trace_processor { |
| |
| // Reads a protobuf trace in chunks and extracts boundaries of trace packets |
| // (or subfields, for the case of ftrace) with their timestamps. |
| class ProtoTraceTokenizer { |
| public: |
| ProtoTraceTokenizer(); |
| |
| template <typename Callback = util::Status(TraceBlobView)> |
| util::Status Tokenize(TraceBlobView blob, Callback callback) { |
| const uint8_t* data = blob.data(); |
| size_t size = blob.size(); |
| if (!partial_buf_.empty()) { |
| // It takes ~5 bytes for a proto preamble + the varint size. |
| const size_t kHeaderBytes = 5; |
| if (PERFETTO_UNLIKELY(partial_buf_.size() < kHeaderBytes)) { |
| size_t missing_len = std::min(kHeaderBytes - partial_buf_.size(), size); |
| partial_buf_.insert(partial_buf_.end(), &data[0], &data[missing_len]); |
| if (partial_buf_.size() < kHeaderBytes) |
| return util::OkStatus(); |
| data += missing_len; |
| size -= missing_len; |
| } |
| |
| // At this point we have enough data in |partial_buf_| to read at least |
| // the field header and know the size of the next TracePacket. |
| const uint8_t* pos = &partial_buf_[0]; |
| uint8_t proto_field_tag = *pos; |
| uint64_t field_size = 0; |
| // We cannot do &partial_buf_[partial_buf_.size()] because that crashes |
| // on MSVC STL debug builds, so does &*partial_buf_.end(). |
| const uint8_t* next = protozero::proto_utils::ParseVarInt( |
| ++pos, &partial_buf_.front() + partial_buf_.size(), &field_size); |
| bool parse_failed = next == pos; |
| pos = next; |
| if (proto_field_tag != kTracePacketTag || field_size == 0 || |
| parse_failed) { |
| return util::ErrStatus( |
| "Failed parsing a TracePacket from the partial buffer"); |
| } |
| |
| // At this point we know how big the TracePacket is. |
| size_t hdr_size = static_cast<size_t>(pos - &partial_buf_[0]); |
| size_t size_incl_header = static_cast<size_t>(field_size + hdr_size); |
| PERFETTO_DCHECK(size_incl_header > partial_buf_.size()); |
| |
| // There is a good chance that between the |partial_buf_| and the new |
| // |data| of the current call we have enough bytes to parse a TracePacket. |
| if (partial_buf_.size() + size >= size_incl_header) { |
| // Create a new buffer for the whole TracePacket and copy into that: |
| // 1) The beginning of the TracePacket (including the proto header) from |
| // the partial buffer. |
| // 2) The rest of the TracePacket from the current |data| buffer (note |
| // that we might have consumed already a few bytes form |data| |
| // earlier in this function, hence we need to keep |off| into |
| // account). |
| TraceBlob glued = TraceBlob::Allocate(size_incl_header); |
| memcpy(glued.data(), partial_buf_.data(), partial_buf_.size()); |
| // |size_missing| is the number of bytes for the rest of the TracePacket |
| // in |data|. |
| size_t size_missing = size_incl_header - partial_buf_.size(); |
| memcpy(glued.data() + partial_buf_.size(), &data[0], size_missing); |
| data += size_missing; |
| size -= size_missing; |
| partial_buf_.clear(); |
| RETURN_IF_ERROR( |
| ParseInternal(TraceBlobView(std::move(glued)), callback)); |
| } else { |
| partial_buf_.insert(partial_buf_.end(), data, &data[size]); |
| return util::OkStatus(); |
| } |
| } |
| return ParseInternal(blob.slice(data, size), callback); |
| } |
| |
| private: |
| static constexpr uint8_t kTracePacketTag = |
| protozero::proto_utils::MakeTagLengthDelimited( |
| protos::pbzero::Trace::kPacketFieldNumber); |
| |
| template <typename Callback = util::Status(TraceBlobView)> |
| util::Status ParseInternal(TraceBlobView whole_buf, Callback callback) { |
| static constexpr auto kLengthDelimited = |
| protozero::proto_utils::ProtoWireType::kLengthDelimited; |
| const uint8_t* const start = whole_buf.data(); |
| protos::pbzero::Trace::Decoder decoder(whole_buf.data(), whole_buf.size()); |
| for (auto it = decoder.packet(); it; ++it) { |
| if (PERFETTO_UNLIKELY(it->type() != kLengthDelimited)) { |
| return base::ErrStatus("Failed to parse TracePacket bounds"); |
| } |
| protozero::ConstBytes packet = *it; |
| TraceBlobView sliced = whole_buf.slice(packet.data, packet.size); |
| RETURN_IF_ERROR(ParsePacket(std::move(sliced), callback)); |
| } |
| |
| const size_t bytes_left = decoder.bytes_left(); |
| if (bytes_left > 0) { |
| PERFETTO_DCHECK(partial_buf_.empty()); |
| partial_buf_.insert(partial_buf_.end(), &start[decoder.read_offset()], |
| &start[decoder.read_offset() + bytes_left]); |
| } |
| return util::OkStatus(); |
| } |
| |
| template <typename Callback = util::Status(TraceBlobView)> |
| util::Status ParsePacket(TraceBlobView packet, Callback callback) { |
| protos::pbzero::TracePacket::Decoder decoder(packet.data(), |
| packet.length()); |
| if (decoder.has_compressed_packets()) { |
| if (!util::IsGzipSupported()) { |
| return util::Status( |
| "Cannot decode compressed packets. Zlib not enabled"); |
| } |
| |
| protozero::ConstBytes field = decoder.compressed_packets(); |
| TraceBlobView compressed_packets = packet.slice(field.data, field.size); |
| TraceBlobView packets; |
| |
| RETURN_IF_ERROR(Decompress(std::move(compressed_packets), &packets)); |
| |
| const uint8_t* start = packets.data(); |
| const uint8_t* end = packets.data() + packets.length(); |
| const uint8_t* ptr = start; |
| while ((end - ptr) > 2) { |
| const uint8_t* packet_outer = ptr; |
| if (PERFETTO_UNLIKELY(*ptr != kTracePacketTag)) |
| return util::ErrStatus("Expected TracePacket tag"); |
| uint64_t packet_size = 0; |
| ptr = protozero::proto_utils::ParseVarInt(++ptr, end, &packet_size); |
| const uint8_t* packet_start = ptr; |
| ptr += packet_size; |
| if (PERFETTO_UNLIKELY((ptr - packet_outer) < 2 || ptr > end)) |
| return util::ErrStatus("Invalid packet size"); |
| |
| TraceBlobView sliced = |
| packets.slice(packet_start, static_cast<size_t>(packet_size)); |
| RETURN_IF_ERROR(ParsePacket(std::move(sliced), callback)); |
| } |
| return util::OkStatus(); |
| } |
| return callback(std::move(packet)); |
| } |
| |
| util::Status Decompress(TraceBlobView input, TraceBlobView* output); |
| |
| // Used to glue together trace packets that span across two (or more) |
| // Parse() boundaries. |
| std::vector<uint8_t> partial_buf_; |
| |
| // Allows support for compressed trace packets. |
| util::GzipDecompressor decompressor_; |
| }; |
| |
| } // namespace trace_processor |
| } // namespace perfetto |
| |
| #endif // SRC_TRACE_PROCESSOR_IMPORTERS_PROTO_PROTO_TRACE_TOKENIZER_H_ |