1 /* 2 * Copyright (C) 2020 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 29 #pragma once 30 31 #include <stddef.h> 32 #include <stdint.h> 33 34 /* 35 * Implement fast stack unwinding for stack frames with frame pointers. Stores at most num_entries 36 * return addresses to buffer buf. Returns the number of available return addresses, which may be 37 * greater than num_entries. 38 * 39 * This function makes no guarantees about its behavior on encountering a frame built without frame 40 * pointers, except that it should not crash or enter an infinite loop, and that any frames prior to 41 * the frame built without frame pointers should be correct. 42 * 43 * This function is only meant to be used with memory safety tools such as sanitizers which need to 44 * take stack traces efficiently. Normal applications should use APIs such as libunwindstack or 45 * _Unwind_Backtrace. 46 */ 47 extern "C" size_t android_unsafe_frame_pointer_chase(uintptr_t* buf, size_t num_entries); 48