projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| cfc91acd | 1 | /* Return backtrace of current program state. |
| 0e66ade5 | 2 | Copyright (C) 1998, 2000, 2002, 2005 Free Software Foundation, Inc. |
| cfc91acd RM |
3 | This file is part of the GNU C Library. |
| 4 | ||
| 5 | The GNU C Library is free software; you can redistribute it and/or | |
| 6 | modify it under the terms of the GNU Library General Public License as | |
| 7 | published by the Free Software Foundation; either version 2 of the | |
| 8 | License, or (at your option) any later version. | |
| 9 | ||
| 10 | The GNU C Library is distributed in the hope that it will be useful, | |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 | Library General Public License for more details. | |
| 14 | ||
| 15 | You should have received a copy of the GNU Library General Public | |
| 16 | License along with the GNU C Library; see the file COPYING.LIB. If not, | |
| 17 | write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
| 18 | Boston, MA 02111-1307, USA. */ | |
| 19 | ||
| 20 | #include <execinfo.h> | |
| 21 | #include <stddef.h> | |
| 22 | #include <bp-checks.h> | |
| 23 | ||
| 24 | /* This is the stack layout we see with every stack frame. | |
| 25 | Note that every routine is required by the ABI to lay out the stack | |
| 26 | like this. | |
| 27 | ||
| 28 | +----------------+ +-----------------+ | |
| 29 | %r1 -> | %r1 last frame--------> | %r1 last frame--->... --> NULL | |
| 30 | | | | | | |
| 31 | | cr save | | cr save | | |
| 32 | | | | | | |
| 33 | | (unused) | | return address | | |
| 34 | +----------------+ +-----------------+ | |
| 35 | */ | |
| 36 | struct layout | |
| 37 | { | |
| 38 | struct layout *__unbounded next; | |
| 39 | long condition_register; | |
| 40 | void *__unbounded return_address; | |
| 41 | }; | |
| 42 | ||
| 43 | int | |
| 44 | __backtrace (void **array, int size) | |
| 45 | { | |
| 46 | struct layout *current; | |
| 47 | int count; | |
| 48 | ||
| 49 | /* Force gcc to spill LR. */ | |
| 50 | asm volatile ("" : "=l"(current)); | |
| 51 | ||
| 52 | /* Get the address on top-of-stack. */ | |
| 53 | asm volatile ("ld %0,0(1)" : "=r"(current)); | |
| 54 | current = BOUNDED_1 (current); | |
| 55 | ||
| 56 | for ( count = 0; | |
| 57 | current != NULL && count < size; | |
| 58 | current = BOUNDED_1 (current->next), count++) | |
| 59 | array[count] = current->return_address; | |
| 60 | ||
| 61 | /* It's possible the second-last stack frame can't return | |
| 62 | (that is, it's __libc_start_main), in which case | |
| 63 | the CRT startup code will have set its LR to 'NULL'. */ | |
| 64 | if (count > 0 && array[count-1] == NULL) | |
| 65 | count--; | |
| 66 | ||
| 67 | return count; | |
| 68 | } | |
| 69 | weak_alias (__backtrace, backtrace) | |
| 0e66ade5 | 70 | libc_hidden_def (__backtrace) |