lib/ObjectYAML/MinidumpEmitter.cpp

   1 //===- yaml2minidump.cpp - Convert a YAML file to a minidump file ---------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/ObjectYAML/MinidumpYAML.h"
  10 #include "llvm/ObjectYAML/yaml2obj.h"
  11 #include "llvm/Support/ConvertUTF.h"
  12 #include "llvm/Support/raw_ostream.h"
  13
  14 using namespace llvm;
  15 using namespace llvm::minidump;
  16 using namespace llvm::MinidumpYAML;
  17
  18 namespace {
  19 /// A helper class to manage the placement of various structures into the final
  20 /// minidump binary. Space for objects can be allocated via various allocate***
  21 /// methods, while the final minidump file is written by calling the writeTo
  22 /// method. The plain versions of allocation functions take a reference to the
  23 /// data which is to be written (and hence the data must be available until
  24 /// writeTo is called), while the "New" versions allocate the data in an
  25 /// allocator-managed buffer, which is available until the allocator object is
  26 /// destroyed. For both kinds of functions, it is possible to modify the
  27 /// data for which the space has been "allocated" until the final writeTo call.
  28 /// This is useful for "linking" the allocated structures via their offsets.
  29 class BlobAllocator {
  30 public:
  31   size_t tell() const { return NextOffset; }
  32
  33   size_t allocateCallback(size_t Size,
  34                           std::function<void(raw_ostream &)> Callback) {
  35     size_t Offset = NextOffset;
  36     NextOffset += Size;
  37     Callbacks.push_back(std::move(Callback));
  38     return Offset;
  39   }
  40
  41   size_t allocateBytes(ArrayRef<uint8_t> Data) {
  42     return allocateCallback(
  43         Data.size(), [Data](raw_ostream &OS) { OS << toStringRef(Data); });
  44   }
  45
  46   size_t allocateBytes(yaml::BinaryRef Data) {
  47     return allocateCallback(Data.binary_size(), [Data](raw_ostream &OS) {
  48       Data.writeAsBinary(OS);
  49     });
  50   }
  51
  52   template <typename T> size_t allocateArray(ArrayRef<T> Data) {
  53     return allocateBytes({reinterpret_cast<const uint8_t *>(Data.data()),
  54                           sizeof(T) * Data.size()});
  55   }
  56
  57   template <typename T, typename RangeType>
  58   std::pair<size_t, MutableArrayRef<T>>
  59   allocateNewArray(const iterator_range<RangeType> &Range);
  60
  61   template <typename T> size_t allocateObject(const T &Data) {
  62     return allocateArray(makeArrayRef(Data));
  63   }
  64
  65   template <typename T, typename... Types>
  66   std::pair<size_t, T *> allocateNewObject(Types &&... Args) {
  67     T *Object = new (Temporaries.Allocate<T>()) T(std::forward<Types>(Args)...);
  68     return {allocateObject(*Object), Object};
  69   }
  70
  71   size_t allocateString(StringRef Str);
  72
  73   void writeTo(raw_ostream &OS) const;
  74
  75 private:
  76   size_t NextOffset = 0;
  77
  78   BumpPtrAllocator Temporaries;
  79   std::vector<std::function<void(raw_ostream &)>> Callbacks;
  80 };
  81 } // namespace
  82
  83 template <typename T, typename RangeType>
  84 std::pair<size_t, MutableArrayRef<T>>
  85 BlobAllocator::allocateNewArray(const iterator_range<RangeType> &Range) {
  86   size_t Num = std::distance(Range.begin(), Range.end());
  87   MutableArrayRef<T> Array(Temporaries.Allocate<T>(Num), Num);
  88   std::uninitialized_copy(Range.begin(), Range.end(), Array.begin());
  89   return {allocateArray(Array), Array};
  90 }
  91
  92 size_t BlobAllocator::allocateString(StringRef Str) {
  93   SmallVector<UTF16, 32> WStr;
  94   bool OK = convertUTF8ToUTF16String(Str, WStr);
  95   assert(OK && "Invalid UTF8 in Str?");
  96   (void)OK;
  97
  98   // The utf16 string is null-terminated, but the terminator is not counted in
  99   // the string size.
 100   WStr.push_back(0);
 101   size_t Result =
 102       allocateNewObject<support::ulittle32_t>(2 * (WStr.size() - 1)).first;
 103   allocateNewArray<support::ulittle16_t>(make_range(WStr.begin(), WStr.end()));
 104   return Result;
 105 }
 106
 107 void BlobAllocator::writeTo(raw_ostream &OS) const {
 108   size_t BeginOffset = OS.tell();
 109   for (const auto &Callback : Callbacks)
 110     Callback(OS);
 111   assert(OS.tell() == BeginOffset + NextOffset &&
 112          "Callbacks wrote an unexpected number of bytes.");
 113   (void)BeginOffset;
 114 }
 115
 116 static LocationDescriptor layout(BlobAllocator &File, yaml::BinaryRef Data) {
 117   return {support::ulittle32_t(Data.binary_size()),
 118           support::ulittle32_t(File.allocateBytes(Data))};
 119 }
 120
 121 static size_t layout(BlobAllocator &File, MinidumpYAML::ExceptionStream &S) {
 122   File.allocateObject(S.MDExceptionStream);
 123
 124   size_t DataEnd = File.tell();
 125
 126   // Lay out the thread context data, (which is not a part of the stream).
 127   // TODO: This usually (always?) matches the thread context of the
 128   // corresponding thread, and may overlap memory regions as well.  We could
 129   // add a level of indirection to the MinidumpYAML format (like an array of
 130   // Blobs that the LocationDescriptors index into) to be able to distinguish
 131   // the cases where location descriptions overlap vs happen to reference
 132   // identical data.
 133   S.MDExceptionStream.ThreadContext = layout(File, S.ThreadContext);
 134
 135   return DataEnd;
 136 }
 137
 138 static void layout(BlobAllocator &File, MemoryListStream::entry_type &Range) {
 139   Range.Entry.Memory = layout(File, Range.Content);
 140 }
 141
 142 static void layout(BlobAllocator &File, ModuleListStream::entry_type &M) {
 143   M.Entry.ModuleNameRVA = File.allocateString(M.Name);
 144
 145   M.Entry.CvRecord = layout(File, M.CvRecord);
 146   M.Entry.MiscRecord = layout(File, M.MiscRecord);
 147 }
 148
 149 static void layout(BlobAllocator &File, ThreadListStream::entry_type &T) {
 150   T.Entry.Stack.Memory = layout(File, T.Stack);
 151   T.Entry.Context = layout(File, T.Context);
 152 }
 153
 154 template <typename EntryT>
 155 static size_t layout(BlobAllocator &File,
 156                      MinidumpYAML::detail::ListStream<EntryT> &S) {
 157
 158   File.allocateNewObject<support::ulittle32_t>(S.Entries.size());
 159   for (auto &E : S.Entries)
 160     File.allocateObject(E.Entry);
 161
 162   size_t DataEnd = File.tell();
 163
 164   // Lay out the auxiliary data, (which is not a part of the stream).
 165   DataEnd = File.tell();
 166   for (auto &E : S.Entries)
 167     layout(File, E);
 168
 169   return DataEnd;
 170 }
 171
 172 static Directory layout(BlobAllocator &File, Stream &S) {
 173   Directory Result;
 174   Result.Type = S.Type;
 175   Result.Location.RVA = File.tell();
 176   Optional<size_t> DataEnd;
 177   switch (S.Kind) {
 178   case Stream::StreamKind::Exception:
 179     DataEnd = layout(File, cast<MinidumpYAML::ExceptionStream>(S));
 180     break;
 181   case Stream::StreamKind::MemoryInfoList: {
 182     MemoryInfoListStream &InfoList = cast<MemoryInfoListStream>(S);
 183     File.allocateNewObject<minidump::MemoryInfoListHeader>(
 184         sizeof(minidump::MemoryInfoListHeader), sizeof(minidump::MemoryInfo),
 185         InfoList.Infos.size());
 186     File.allocateArray(makeArrayRef(InfoList.Infos));
 187     break;
 188   }
 189   case Stream::StreamKind::MemoryList:
 190     DataEnd = layout(File, cast<MemoryListStream>(S));
 191     break;
 192   case Stream::StreamKind::ModuleList:
 193     DataEnd = layout(File, cast<ModuleListStream>(S));
 194     break;
 195   case Stream::StreamKind::RawContent: {
 196     RawContentStream &Raw = cast<RawContentStream>(S);
 197     File.allocateCallback(Raw.Size, [&Raw](raw_ostream &OS) {
 198       Raw.Content.writeAsBinary(OS);
 199       assert(Raw.Content.binary_size() <= Raw.Size);
 200       OS << std::string(Raw.Size - Raw.Content.binary_size(), '\0');
 201     });
 202     break;
 203   }
 204   case Stream::StreamKind::SystemInfo: {
 205     SystemInfoStream &SystemInfo = cast<SystemInfoStream>(S);
 206     File.allocateObject(SystemInfo.Info);
 207     // The CSD string is not a part of the stream.
 208     DataEnd = File.tell();
 209     SystemInfo.Info.CSDVersionRVA = File.allocateString(SystemInfo.CSDVersion);
 210     break;
 211   }
 212   case Stream::StreamKind::TextContent:
 213     File.allocateArray(arrayRefFromStringRef(cast<TextContentStream>(S).Text));
 214     break;
 215   case Stream::StreamKind::ThreadList:
 216     DataEnd = layout(File, cast<ThreadListStream>(S));
 217     break;
 218   }
 219   // If DataEnd is not set, we assume everything we generated is a part of the
 220   // stream.
 221   Result.Location.DataSize =
 222       DataEnd.getValueOr(File.tell()) - Result.Location.RVA;
 223   return Result;
 224 }
 225
 226 namespace llvm {
 227 namespace yaml {
 228
 229 bool yaml2minidump(MinidumpYAML::Object &Obj, raw_ostream &Out,
 230                    ErrorHandler /*EH*/) {
 231   BlobAllocator File;
 232   File.allocateObject(Obj.Header);
 233
 234   std::vector<Directory> StreamDirectory(Obj.Streams.size());
 235   Obj.Header.StreamDirectoryRVA =
 236       File.allocateArray(makeArrayRef(StreamDirectory));
 237   Obj.Header.NumberOfStreams = StreamDirectory.size();
 238
 239   for (auto &Stream : enumerate(Obj.Streams))
 240     StreamDirectory[Stream.index()] = layout(File, *Stream.value());
 241
 242   File.writeTo(Out);
 243   return true;
 244 }
 245
 246 } // namespace yaml
 247 } // namespace llvm