1 /*
2  * Copyright (C) 2008 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 #include <unwind.h>
29 #include <sys/types.h>
30 
31 // =============================================================================
32 // stack trace functions
33 // =============================================================================
34 
35 typedef struct
36 {
37     size_t count;
38     intptr_t* addrs;
39 } stack_crawl_state_t;
40 
41 typedef struct _Unwind_Context __unwind_context;
42 
trace_function(__unwind_context * context,void * arg)43 static _Unwind_Reason_Code trace_function(__unwind_context *context, void *arg)
44 {
45     stack_crawl_state_t* state = (stack_crawl_state_t*)arg;
46     if (state->count) {
47         intptr_t ip = (intptr_t)_Unwind_GetIP(context);
48         if (ip) {
49             state->addrs[0] = ip;
50             state->addrs++;
51             state->count--;
52             return _URC_NO_REASON;
53         }
54     }
55     /*
56      * If we run out of space to record the address or 0 has been seen, stop
57      * unwinding the stack.
58      */
59     return _URC_END_OF_STACK;
60 }
61 
heaptracker_stacktrace(intptr_t * addrs,size_t max_entries)62 int heaptracker_stacktrace(intptr_t* addrs, size_t max_entries)
63 {
64     stack_crawl_state_t state;
65     state.count = max_entries;
66     state.addrs = (intptr_t*)addrs;
67     _Unwind_Backtrace(trace_function, (void*)&state);
68     return max_entries - state.count;
69 }
70