1 /**************************************************************************
2 *
3 * Copyright 2009 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28 /**
29 * @file
30 * Stack backtracing.
31 *
32 * @author Jose Fonseca <jfonseca@vmware.com>
33 */
34
35 #include "u_debug.h"
36 #include "u_debug_symbol.h"
37 #include "u_debug_stack.h"
38
39
40 void
debug_backtrace_capture(struct debug_stack_frame * backtrace,unsigned start_frame,unsigned nr_frames)41 debug_backtrace_capture(struct debug_stack_frame *backtrace,
42 unsigned start_frame,
43 unsigned nr_frames)
44 {
45 const void **frame_pointer = NULL;
46 unsigned i = 0;
47
48 if(!nr_frames)
49 return;
50
51 #if defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86)
52 __asm__ __volatile__("mov (%%ebp),%0": "=r" (frame_pointer));
53 frame_pointer = (const void **)frame_pointer[0];
54 #elif defined(PIPE_CC_GCC)
55 frame_pointer = ((const void **)__builtin_frame_address(1));
56 #elif defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86)
57 __asm {
58 mov frame_pointer, ebp
59 }
60 frame_pointer = (const void **)frame_pointer[0];
61 #else
62 frame_pointer = NULL;
63 #endif
64
65
66 #ifdef PIPE_ARCH_X86
67 while(nr_frames) {
68 const void **next_frame_pointer;
69
70 if(!frame_pointer)
71 break;
72
73 if(start_frame)
74 --start_frame;
75 else {
76 backtrace[i++].function = frame_pointer[1];
77 --nr_frames;
78 }
79
80 next_frame_pointer = (const void **)frame_pointer[0];
81
82 /* Limit the stack walk to avoid referencing undefined memory */
83 if((uintptr_t)next_frame_pointer <= (uintptr_t)frame_pointer ||
84 (uintptr_t)next_frame_pointer > (uintptr_t)frame_pointer + 64*1024)
85 break;
86
87 frame_pointer = next_frame_pointer;
88 }
89 #else
90 (void) frame_pointer;
91 #endif
92
93 while(nr_frames) {
94 backtrace[i++].function = NULL;
95 --nr_frames;
96 }
97 }
98
99
100 void
debug_backtrace_dump(const struct debug_stack_frame * backtrace,unsigned nr_frames)101 debug_backtrace_dump(const struct debug_stack_frame *backtrace,
102 unsigned nr_frames)
103 {
104 unsigned i;
105
106 for(i = 0; i < nr_frames; ++i) {
107 if(!backtrace[i].function)
108 break;
109 debug_symbol_print(backtrace[i].function);
110 }
111 }
112
113