diff --git a/src/blob_serializer_deserializer-inl.h b/src/blob_serializer_deserializer-inl.h index f47a1e0cdf8a44..ecf664fc807b68 100644 --- a/src/blob_serializer_deserializer-inl.h +++ b/src/blob_serializer_deserializer-inl.h @@ -238,7 +238,8 @@ size_t BlobSerializer::WriteVector(const std::vector& data) { if (is_debug) { std::string str = std::is_arithmetic_v ? "" : ToStr(data); std::string name = GetName(); - Debug("\nWriteVector<%s>() (%d-byte), count=%d: %s\n", + Debug("\nAt 0x%x: WriteVector<%s>() (%d-byte), count=%d: %s\n", + sink.size(), name.c_str(), sizeof(T), data.size(), @@ -270,7 +271,10 @@ size_t BlobSerializer::WriteVector(const std::vector& data) { template size_t BlobSerializer::WriteStringView(std::string_view data, StringLogMode mode) { - Debug("WriteStringView(), length=%zu: %p\n", data.size(), data.data()); + Debug("At 0x%x: WriteStringView(), length=%zu: %p\n", + sink.size(), + data.size(), + data.data()); size_t written_total = WriteArithmetic(data.size()); size_t length = data.size(); @@ -294,6 +298,8 @@ size_t BlobSerializer::WriteString(const std::string& data) { return WriteStringView(data, StringLogMode::kAddressAndContent); } +static size_t kPreviewCount = 16; + // Helper for writing an array of numeric types. template template @@ -301,10 +307,18 @@ size_t BlobSerializer::WriteArithmetic(const T* data, size_t count) { static_assert(std::is_arithmetic_v, "Arithmetic type"); DCHECK_GT(count, 0); // Should not write contents for vectors of size 0. if (is_debug) { - std::string str = - "{ " + std::to_string(data[0]) + (count > 1 ? ", ... }" : " }"); + size_t preview_count = count < kPreviewCount ? count : kPreviewCount; + std::string str = "{ "; + for (size_t i = 0; i < preview_count; ++i) { + str += (std::to_string(data[i]) + ","); + } + if (count > preview_count) { + str += "..."; + } + str += "}"; std::string name = GetName(); - Debug("Write<%s>() (%zu-byte), count=%zu: %s", + Debug("At 0x%x: Write<%s>() (%zu-byte), count=%zu: %s", + sink.size(), name.c_str(), sizeof(T), count, diff --git a/src/node.cc b/src/node.cc index b43368715cc056..cfda35d4b9eb27 100644 --- a/src/node.cc +++ b/src/node.cc @@ -1337,18 +1337,24 @@ ExitCode GenerateAndWriteSnapshotData(const SnapshotData** snapshot_data_ptr, return exit_code; } } else { + std::optional builder_script_content; // Otherwise, load and run the specified builder script. std::unique_ptr generated_data = std::make_unique(); - std::string builder_script_content; - int r = ReadFileSync(&builder_script_content, builder_script.c_str()); - if (r != 0) { - FPrintF(stderr, - "Cannot read builder script %s for building snapshot. %s: %s", - builder_script, - uv_err_name(r), - uv_strerror(r)); - return ExitCode::kGenericUserError; + if (builder_script != "node:generate_default_snapshot") { + builder_script_content = std::string(); + int r = ReadFileSync(&(builder_script_content.value()), + builder_script.c_str()); + if (r != 0) { + FPrintF(stderr, + "Cannot read builder script %s for building snapshot. %s: %s\n", + builder_script, + uv_err_name(r), + uv_strerror(r)); + return ExitCode::kGenericUserError; + } + } else { + snapshot_config.builder_script_path = std::nullopt; } exit_code = node::SnapshotBuilder::Generate(generated_data.get(), diff --git a/src/node_snapshotable.cc b/src/node_snapshotable.cc index f665d9dad01feb..eaeafd8e16a91c 100644 --- a/src/node_snapshotable.cc +++ b/src/node_snapshotable.cc @@ -599,16 +599,17 @@ std::vector SnapshotData::ToBlob() const { size_t written_total = 0; // Metadata - w.Debug("Write magic %" PRIx32 "\n", kMagic); + w.Debug("0x%x: Write magic %" PRIx32 "\n", w.sink.size(), kMagic); written_total += w.WriteArithmetic(kMagic); - w.Debug("Write metadata\n"); + w.Debug("0x%x: Write metadata\n", w.sink.size()); written_total += w.Write(metadata); - + w.Debug("0x%x: Write snapshot blob\n", w.sink.size()); written_total += w.Write(v8_snapshot_blob_data); - w.Debug("Write isolate_data_indices\n"); + w.Debug("0x%x: Write IsolateDataSerializeInfo\n", w.sink.size()); written_total += w.Write(isolate_data_info); + w.Debug("0x%x: Write EnvSerializeInfo\n", w.sink.size()); written_total += w.Write(env_info); - w.Debug("Write code_cache\n"); + w.Debug("0x%x: Write CodeCacheInfo\n", w.sink.size()); written_total += w.WriteVector(code_cache); w.Debug("SnapshotData::ToBlob() Wrote %d bytes\n", written_total); diff --git a/test/parallel/test-snapshot-reproducible.js b/test/parallel/test-snapshot-reproducible.js new file mode 100644 index 00000000000000..f9392a7fb4adfc --- /dev/null +++ b/test/parallel/test-snapshot-reproducible.js @@ -0,0 +1,70 @@ +'use strict'; + +require('../common'); +const { spawnSyncAndAssert } = require('../common/child_process'); +const tmpdir = require('../common/tmpdir'); +const fs = require('fs'); +const assert = require('assert'); + +// When the test fails this helper can be modified to write outputs +// differently and aid debugging. +function log(line) { + console.log(line); +} + +function generateSnapshot() { + tmpdir.refresh(); + + spawnSyncAndAssert( + process.execPath, + [ + '--random_seed=42', + '--predictable', + '--build-snapshot', + 'node:generate_default_snapshot', + ], + { + env: { ...process.env, NODE_DEBUG_NATIVE: 'SNAPSHOT_SERDES' }, + cwd: tmpdir.path + }, + { + stderr(output) { + const lines = output.split('\n'); + for (const line of lines) { + if (line.startsWith('0x')) { + log(line); + } + } + }, + } + ); + const blobPath = tmpdir.resolve('snapshot.blob'); + return fs.readFileSync(blobPath); +} + +const buf1 = generateSnapshot(); +const buf2 = generateSnapshot(); + +const diff = []; +let offset = 0; +const step = 16; +do { + const length = Math.min(buf1.length - offset, step); + const slice1 = buf1.slice(offset, offset + length).toString('hex'); + const slice2 = buf2.slice(offset, offset + length).toString('hex'); + if (slice1 !== slice2) { + diff.push({ offset: '0x' + (offset).toString(16), slice1, slice2 }); + } + offset += length; +} while (offset < buf1.length); + +assert.strictEqual(offset, buf1.length); +if (offset < buf2.length) { + const length = Math.min(buf2.length - offset, step); + const slice2 = buf2.slice(offset, offset + length).toString('hex'); + diff.push({ offset, slice1: '', slice2 }); + offset += length; +} while (offset < buf2.length); + +assert.deepStrictEqual(diff, []); +assert.strictEqual(buf1.length, buf2.length);