1//===---------------------SharingPtr.cpp ------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "lldb/Utility/SharingPtr.h"
11
12#if defined (ENABLE_SP_LOGGING)
13
14// If ENABLE_SP_LOGGING is defined, then log all shared pointer assignements
15// and allow them to be queried using a pointer by a call to:
16#include <execinfo.h>
17#include <map>
18#include <assert.h>
19#include "lldb/Host/Mutex.h"
20
21#include <vector>
22
23class Backtrace
24{
25public:
26    Backtrace ();
27
28    ~Backtrace ();
29
30    void
31    GetFrames ();
32
33    void
34    Dump () const;
35
36private:
37    void *m_sp_this;
38    std::vector<void *> m_frames;
39};
40
41
42Backtrace::Backtrace () : m_frames()
43{
44}
45
46Backtrace::~Backtrace ()
47{
48}
49
50void
51Backtrace::GetFrames ()
52{
53    void *frames[1024];
54    const int count = ::backtrace (frames, sizeof(frames)/sizeof(void*));
55    if (count > 2)
56        m_frames.assign (frames + 2, frames + (count - 2));
57}
58
59void
60Backtrace::Dump () const
61{
62    if (!m_frames.empty())
63        ::backtrace_symbols_fd (m_frames.data(), m_frames.size(), STDOUT_FILENO);
64    write (STDOUT_FILENO, "\n\n", 2);
65}
66
67extern "C" void track_sp (void *sp_this, void *ptr, long use_count)
68{
69    typedef std::pair<void *, Backtrace> PtrBacktracePair;
70    typedef std::map<void *, PtrBacktracePair> PtrToBacktraceMap;
71    static lldb_private::Mutex g_mutex(lldb_private::Mutex::eMutexTypeNormal);
72    lldb_private::Mutex::Locker locker (g_mutex);
73    static PtrToBacktraceMap g_map;
74
75    if (sp_this)
76    {
77        printf ("sp(%p) -> %p %lu\n", sp_this, ptr, use_count);
78
79        if (ptr)
80        {
81            Backtrace bt;
82            bt.GetFrames();
83            g_map[sp_this] = std::make_pair(ptr, bt);
84        }
85        else
86        {
87            g_map.erase (sp_this);
88        }
89    }
90    else
91    {
92        if (ptr)
93            printf ("Searching for shared pointers that are tracking %p: ", ptr);
94        else
95            printf ("Dump all live shared pointres: ");
96
97        uint32_t matches = 0;
98        PtrToBacktraceMap::iterator pos, end = g_map.end();
99        for (pos = g_map.begin(); pos != end; ++pos)
100        {
101            if (ptr == NULL || pos->second.first == ptr)
102            {
103                ++matches;
104                printf ("\nsp(%p): %p\n", pos->first, pos->second.first);
105                pos->second.second.Dump();
106            }
107        }
108        if (matches == 0)
109        {
110            printf ("none.\n");
111        }
112    }
113}
114// Put dump_sp_refs in the lldb namespace to it gets through our exports lists filter in the LLDB.framework or lldb.so
115namespace lldb {
116
117    void dump_sp_refs (void *ptr)
118    {
119        // Use a specially crafted call to "track_sp" which will
120        // dump info on all live shared pointers that reference "ptr"
121        track_sp (NULL, ptr, 0);
122    }
123
124}
125
126#endif
127
128namespace lldb_private {
129
130namespace imp
131{
132
133
134    shared_count::~shared_count()
135    {
136    }
137
138    void
139    shared_count::add_shared()
140    {
141        increment(shared_owners_);
142    }
143
144    void
145    shared_count::release_shared()
146    {
147        if (decrement(shared_owners_) == -1)
148        {
149            on_zero_shared();
150            delete this;
151        }
152    }
153
154} // imp
155
156
157} // namespace lldb
158
159