1 //===- FDRRecordProducer.h - XRay FDR Mode Record Producer ----------------===//
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 #ifndef LLVM_XRAY_FDRRECORDPRODUCER_H
9 #define LLVM_XRAY_FDRRECORDPRODUCER_H
10 
11 #include "llvm/Support/Error.h"
12 #include "llvm/XRay/FDRRecords.h"
13 #include "llvm/XRay/XRayRecord.h"
14 #include <memory>
15 
16 namespace llvm {
17 namespace xray {
18 
19 class RecordProducer {
20 public:
21   /// All producer implementations must yield either an Error or a non-nullptr
22   /// unique_ptr<Record>.
23   virtual Expected<std::unique_ptr<Record>> produce() = 0;
24   virtual ~RecordProducer() = default;
25 };
26 
27 class FileBasedRecordProducer : public RecordProducer {
28   const XRayFileHeader &Header;
29   DataExtractor &E;
30   uint64_t &OffsetPtr;
31   uint32_t CurrentBufferBytes = 0;
32 
33   // Helper function which gets the next record by speculatively reading through
34   // the log, finding a buffer extents record.
35   Expected<std::unique_ptr<Record>> findNextBufferExtent();
36 
37 public:
FileBasedRecordProducer(const XRayFileHeader & FH,DataExtractor & DE,uint64_t & OP)38   FileBasedRecordProducer(const XRayFileHeader &FH, DataExtractor &DE,
39                           uint64_t &OP)
40       : Header(FH), E(DE), OffsetPtr(OP) {}
41 
42   /// This producer encapsulates the logic for loading a File-backed
43   /// RecordProducer hidden behind a DataExtractor.
44   Expected<std::unique_ptr<Record>> produce() override;
45 };
46 
47 } // namespace xray
48 } // namespace llvm
49 
50 #endif // LLVM_XRAY_FDRRECORDPRODUCER_H
51