1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
|
// Copyright (c) 2006, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef GOOGLE_BREAKPAD_PROCESSOR_STACK_FRAME_H__
#define GOOGLE_BREAKPAD_PROCESSOR_STACK_FRAME_H__
#include <string>
#include "common/using_std_string.h"
#include "google_breakpad/common/breakpad_types.h"
namespace google_breakpad {
class CodeModule;
struct StackFrame {
// Indicates how well the instruction pointer derived during
// stack walking is trusted. Since the stack walker can resort to
// stack scanning, it can wind up with dubious frames.
// In rough order of "trust metric".
enum FrameTrust {
FRAME_TRUST_NONE, // Unknown
FRAME_TRUST_SCAN, // Scanned the stack, found this
FRAME_TRUST_CFI_SCAN, // Found while scanning stack using call frame info
FRAME_TRUST_FP, // Derived from frame pointer
FRAME_TRUST_CFI, // Derived from call frame info
FRAME_TRUST_PREWALKED, // Explicitly provided by some external stack walker.
FRAME_TRUST_CONTEXT // Given as instruction pointer in a context
};
StackFrame()
: instruction(),
module(NULL),
function_name(),
function_base(),
source_file_name(),
source_line(),
source_line_base(),
trust(FRAME_TRUST_NONE) {}
virtual ~StackFrame() {}
// Return a string describing how this stack frame was found
// by the stackwalker.
string trust_description() const {
switch (trust) {
case StackFrame::FRAME_TRUST_CONTEXT:
return "given as instruction pointer in context";
case StackFrame::FRAME_TRUST_PREWALKED:
return "recovered by external stack walker";
case StackFrame::FRAME_TRUST_CFI:
return "call frame info";
case StackFrame::FRAME_TRUST_CFI_SCAN:
return "call frame info with scanning";
case StackFrame::FRAME_TRUST_FP:
return "previous frame's frame pointer";
case StackFrame::FRAME_TRUST_SCAN:
return "stack scanning";
default:
return "unknown";
}
}
// Return the actual return address, as saved on the stack or in a
// register. See the comments for 'instruction', below, for details.
virtual uint64_t ReturnAddress() const { return instruction; }
// The program counter location as an absolute virtual address.
//
// - For the innermost called frame in a stack, this will be an exact
// program counter or instruction pointer value.
//
// - For all other frames, this address is within the instruction that
// caused execution to branch to this frame's callee (although it may
// not point to the exact beginning of that instruction). This ensures
// that, when we look up the source code location for this frame, we
// get the source location of the call, not of the point at which
// control will resume when the call returns, which may be on the next
// line. (If the compiler knows the callee never returns, it may even
// place the call instruction at the very end of the caller's machine
// code, such that the "return address" (which will never be used)
// immediately after the call instruction is in an entirely different
// function, perhaps even from a different source file.)
//
// On some architectures, the return address as saved on the stack or in
// a register is fine for looking up the point of the call. On others, it
// requires adjustment. ReturnAddress returns the address as saved by the
// machine.
uint64_t instruction;
// The module in which the instruction resides.
const CodeModule *module;
// The function name, may be omitted if debug symbols are not available.
string function_name;
// The start address of the function, may be omitted if debug symbols
// are not available.
uint64_t function_base;
// The source file name, may be omitted if debug symbols are not available.
string source_file_name;
// The (1-based) source line number, may be omitted if debug symbols are
// not available.
int source_line;
// The start address of the source line, may be omitted if debug symbols
// are not available.
uint64_t source_line_base;
// Amount of trust the stack walker has in the instruction pointer
// of this frame.
FrameTrust trust;
};
} // namespace google_breakpad
#endif // GOOGLE_BREAKPAD_PROCESSOR_STACK_FRAME_H__
|
