1 //===-- sanitizer_stackdepot.h ----------------------------------*- C++ -*-===//
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 // This file is shared between AddressSanitizer and ThreadSanitizer
10 // run-time libraries.
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef SANITIZER_STACKDEPOT_H
14 #define SANITIZER_STACKDEPOT_H
15 
16 #include "sanitizer_common.h"
17 #include "sanitizer_internal_defs.h"
18 #include "sanitizer_stacktrace.h"
19 
20 namespace __sanitizer {
21 
22 // StackDepot efficiently stores huge amounts of stack traces.
23 struct StackDepotNode;
24 struct StackDepotHandle {
25   StackDepotNode *node_;
26   StackDepotHandle() : node_(nullptr) {}
27   explicit StackDepotHandle(StackDepotNode *node) : node_(node) {}
28   bool valid() { return node_; }
29   u32 id();
30   int use_count();
31   void inc_use_count_unsafe();
32 };
33 
34 const int kStackDepotMaxUseCount = 1U << (SANITIZER_ANDROID ? 16 : 20);
35 
36 StackDepotStats *StackDepotGetStats();
37 u32 StackDepotPut(StackTrace stack);
38 StackDepotHandle StackDepotPut_WithHandle(StackTrace stack);
39 // Retrieves a stored stack trace by the id.
40 StackTrace StackDepotGet(u32 id);
41 
42 void StackDepotLockAll();
43 void StackDepotUnlockAll();
44 
45 // Instantiating this class creates a snapshot of StackDepot which can be
46 // efficiently queried with StackDepotGet(). You can use it concurrently with
47 // StackDepot, but the snapshot is only guaranteed to contain those stack traces
48 // which were stored before it was instantiated.
49 class StackDepotReverseMap {
50  public:
51   StackDepotReverseMap();
52   StackTrace Get(u32 id);
53 
54  private:
55   struct IdDescPair {
56     u32 id;
57     StackDepotNode *desc;
58 
59     static bool IdComparator(const IdDescPair &a, const IdDescPair &b);
60   };
61 
62   InternalMmapVector<IdDescPair> map_;
63 
64   // Disallow evil constructors.
65   StackDepotReverseMap(const StackDepotReverseMap&);
66   void operator=(const StackDepotReverseMap&);
67 };
68 
69 } // namespace __sanitizer
70 
71 #endif // SANITIZER_STACKDEPOT_H
72