Write MINIDUMP_HANDLE_DATA_STREAM to minidump

minidump/minidump_handle_writer.cc

Index: minidump/minidump_handle_writer.cc
diff --git a/minidump/minidump_handle_writer.cc b/minidump/minidump_handle_writer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c5318492b95eda51eef609eabdfe5045a0298273
--- /dev/null
+++ b/minidump/minidump_handle_writer.cc
@@ -0,0 +1,114 @@
+// Copyright 2015 The Crashpad Authors. All rights reserved.
+//
+// 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 "minidump/minidump_handle_writer.h"
+
+#include <string>
+
+#include "base/logging.h"
+#include "minidump/minidump_extensions.h"
+#include "util/file/file_writer.h"
+
+namespace crashpad {
+
+MinidumpHandleDataWriter::MinidumpHandleDataWriter()
+    : handle_data_stream_base_(), handle_descriptors_(), strings_() {
+}
+
+MinidumpHandleDataWriter::~MinidumpHandleDataWriter() {
+}
+
+void MinidumpHandleDataWriter::InitializeFromSnapshot(
+    const std::vector<HandleSnapshot>& handle_snapshots) {
+  DCHECK_EQ(state(), kStateMutable);
+
+  DCHECK(handle_descriptors_.empty());
+  handle_descriptors_.resize(handle_snapshots.size());
+  strings_.reserve(handle_snapshots.size());
+  for (size_t i = 0; i < handle_snapshots.size(); ++i) {
+    const HandleSnapshot& handle_snapshot = handle_snapshots[i];
+    MINIDUMP_HANDLE_DESCRIPTOR& descriptor = handle_descriptors_[i];
+
+    descriptor.Handle = handle_snapshot.handle;
+
+    if (handle_snapshot.type_name.empty()) {
+      descriptor.TypeNameRva = 0;
+    } else {
+      // Because we RegisterRVA() on the string writer below, we preallocate
+      // and never resize the handle_descriptors_ vector.

[Mark Mentovai, 2015/10/21 00:04:21]

Doesn’t this comment belong on the handle_descriptors_.resize() call?

[scottmg, 2015/10/21 00:14:15]

Done.

+      strings_.push_back(new internal::MinidumpUTF16StringWriter());
+      strings_.back()->SetUTF16(handle_snapshot.type_name);

[Mark Mentovai, 2015/10/21 00:04:21]

There’s probably a lot of duplication in these strings. They should be pooled
(or there should be a TODO to pool them).

[scottmg, 2015/10/21 00:14:15]

Yeah, you're right. I'll do that in a follow up.

+      strings_.back()->RegisterRVA(&descriptor.TypeNameRva);
+    }
+
+    descriptor.ObjectNameRva = 0;
+    descriptor.Attributes = handle_snapshot.attributes;
+    descriptor.GrantedAccess = handle_snapshot.granted_access;
+    descriptor.HandleCount = handle_snapshot.handle_count;
+    descriptor.PointerCount = handle_snapshot.pointer_count;
+  }
+}
+
+bool MinidumpHandleDataWriter::Freeze() {
+  DCHECK_EQ(state(), kStateMutable);
+
+  if (!MinidumpStreamWriter::Freeze())
+    return false;
+
+  handle_data_stream_base_.SizeOfHeader = sizeof(MINIDUMP_HANDLE_DATA_STREAM);

[Mark Mentovai, 2015/10/21 00:04:21]

Use the member.

[scottmg, 2015/10/21 00:14:15]

Done.

+  handle_data_stream_base_.SizeOfDescriptor =
+      sizeof(MINIDUMP_HANDLE_DESCRIPTOR);

[Mark Mentovai, 2015/10/21 00:04:21]

Here too, handle_descriptors_[0]

[scottmg, 2015/10/21 00:14:15]

Done.

+  handle_data_stream_base_.NumberOfDescriptors = handle_descriptors_.size();
+  handle_data_stream_base_.Reserved = 0;
+
+  return true;
+}
+
+size_t MinidumpHandleDataWriter::SizeOfObject() {
+  DCHECK_GE(state(), kStateFrozen);
+  return sizeof(handle_data_stream_base_) +
+         sizeof(handle_descriptors_[0]) * handle_descriptors_.size();
+}
+
+std::vector<internal::MinidumpWritable*> MinidumpHandleDataWriter::Children() {
+  DCHECK_GE(state(), kStateFrozen);
+
+  std::vector<MinidumpWritable*> children;
+  for (auto* string : strings_)
+    children.push_back(string);
+  return children;
+}
+
+bool MinidumpHandleDataWriter::WriteObject(FileWriterInterface* file_writer) {
+  DCHECK_EQ(state(), kStateWritable);
+
+  WritableIoVec iov;
+  iov.iov_base = &handle_data_stream_base_;
+  iov.iov_len = sizeof(handle_data_stream_base_);
+  std::vector<WritableIoVec> iovecs(1, iov);
+
+  for (const auto& descriptor : handle_descriptors_) {
+    iov.iov_base = &descriptor;
+    iov.iov_len = sizeof(descriptor);
+    iovecs.push_back(iov);
+  }
+
+  return file_writer->WriteIoVec(&iovecs);
+}
+
+MinidumpStreamType MinidumpHandleDataWriter::StreamType() const {
+  return kMinidumpStreamTypeHandleData;
+}
+
+}  // namespace crashpad