1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 /*
3 * This file is part of the LibreOffice project.
4 *
5 * This Source Code Form is subject to the terms of the Mozilla Public
6 * License, v. 2.0. If a copy of the MPL was not distributed with this
7 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
8 */
9
10 #include <sal/config.h>
11
12 #include <limits>
13 #include <memory>
14
15 #if !defined WIN32_LEAN_AND_MEAN
16 # define WIN32_LEAN_AND_MEAN
17 #endif
18 #include <windows.h>
19 #include <process.h>
20 #include <iostream>
21 #define OPTIONAL
22 #include <DbgHelp.h>
23
24 #include <rtl/ustrbuf.hxx>
25 #include <sal/backtrace.hxx>
26
27 #include <backtraceasstring.hxx>
28
29 namespace {
30
clampToULONG(T n)31 template<typename T> T clampToULONG(T n) {
32 auto const maxUlong = std::numeric_limits<ULONG>::max();
33 return n > maxUlong ? static_cast<T>(maxUlong) : n;
34 }
35
36 }
37
backtraceAsString(sal_uInt32 maxDepth)38 OUString osl::detail::backtraceAsString(sal_uInt32 maxDepth)
39 {
40 std::unique_ptr<sal::BacktraceState> backtrace = sal::backtrace_get( maxDepth );
41 return sal::backtrace_to_string( backtrace.get());
42 }
43
backtrace_get(sal_uInt32 maxDepth)44 std::unique_ptr<sal::BacktraceState> sal::backtrace_get(sal_uInt32 maxDepth)
45 {
46 assert(maxDepth != 0);
47 maxDepth = clampToULONG(maxDepth);
48
49 auto pStack = new void *[maxDepth];
50 // https://msdn.microsoft.com/en-us/library/windows/desktop/bb204633.aspx
51 // "CaptureStackBackTrace function" claims that you "can capture up to
52 // MAXUSHORT frames", and on Windows Server 2003 and Windows XP it even
53 // "must be less than 63", but assume that a too large input value is
54 // clamped internally, instead of resulting in an error:
55 int nFrames = CaptureStackBackTrace( 0, static_cast<ULONG>(maxDepth), pStack, nullptr );
56
57 return std::unique_ptr<BacktraceState>(new BacktraceState{ pStack, nFrames });
58 }
59
backtrace_to_string(BacktraceState * backtraceState)60 OUString sal::backtrace_to_string(BacktraceState* backtraceState)
61 {
62 HANDLE hProcess = GetCurrentProcess();
63 // https://docs.microsoft.com/en-us/windows/win32/api/dbghelp/nf-dbghelp-syminitialize
64 // says to not initialize more than once. This still leaks for some
65 // reason if called often enough.
66 static bool needsInit = true;
67 if( needsInit )
68 SymInitialize( hProcess, nullptr, true );
69 else
70 SymRefreshModuleList( hProcess );
71 SYMBOL_INFO * pSymbol;
72 pSymbol = static_cast<SYMBOL_INFO *>(calloc( sizeof( SYMBOL_INFO ) + 1024 * sizeof( char ), 1 ));
73 assert(pSymbol);
74 pSymbol->MaxNameLen = 1024 - 1;
75 pSymbol->SizeOfStruct = sizeof( SYMBOL_INFO );
76
77 auto nFrames = backtraceState->nDepth;
78 OUStringBuffer aBuf;
79 for( int i = 0; i < nFrames; i++ )
80 {
81 SymFromAddr( hProcess, reinterpret_cast<DWORD64>(backtraceState->buffer[ i ]), nullptr, pSymbol );
82 aBuf.append( static_cast<sal_Int32>(nFrames - i - 1) );
83 aBuf.append( ": " );
84 aBuf.appendAscii( pSymbol->Name );
85 aBuf.append( " - 0x" );
86 aBuf.append( static_cast<sal_Int64>(pSymbol->Address), 16 );
87 aBuf.append( "\n" );
88 }
89
90 free( pSymbol );
91
92 return aBuf.makeStringAndClear();
93 }
94
95
96 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
97