| /* libunwind - a platform-independent unwind library |
| Copyright (C) 2002-2003 Hewlett-Packard Co |
| Contributed by David Mosberger-Tang <davidm@hpl.hp.com> |
| |
| Modified for x86_64 by Max Asbock <masbock@us.ibm.com> |
| |
| This file is part of libunwind. |
| |
| Permission is hereby granted, free of charge, to any person obtaining |
| a copy of this software and associated documentation files (the |
| "Software"), to deal in the Software without restriction, including |
| without limitation the rights to use, copy, modify, merge, publish, |
| distribute, sublicense, and/or sell copies of the Software, and to |
| permit persons to whom the Software is furnished to do so, subject to |
| the following conditions: |
| |
| The above copyright notice and this permission notice shall be |
| included in all copies or substantial portions of the Software. |
| |
| THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
| LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
| OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
| WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ |
| |
| #include "unwind_i.h" |
| #include "ucontext_i.h" |
| #include <signal.h> |
| |
| PROTECTED int |
| unw_step (unw_cursor_t *cursor) |
| { |
| struct cursor *c = (struct cursor *) cursor; |
| int ret, i; |
| |
| /* Only attempt DWARF based unwinding since DWARF frame info is |
| always expected to be there. With the exception of signal frames. */ |
| |
| if (!unw_is_signal_frame (cursor)) |
| { |
| if ((ret = dwarf_step (&c->dwarf)) < 0) |
| { |
| Debug(1, "dwarf step failed\n"); |
| return ret; |
| } |
| } |
| else |
| { |
| struct dwarf_loc rbp_loc, rsp_loc, rip_loc; |
| unw_word_t ucontext = c->dwarf.cfa; |
| |
| Debug(1, "signal frame, skip over trampoline\n"); |
| |
| c->sigcontext_format = X86_64_SCF_LINUX_RT_SIGFRAME; |
| c->sigcontext_addr = c->dwarf.cfa; |
| |
| rsp_loc = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RSP, 0); |
| rbp_loc = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RBP, 0); |
| rip_loc = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RIP, 0); |
| |
| ret = dwarf_get (&c->dwarf, rsp_loc, &c->dwarf.cfa); |
| if (ret < 0) |
| return ret; |
| |
| /* Mark all registers unsaved */ |
| for (i = 0; i < DWARF_NUM_PRESERVED_REGS; ++i) |
| c->dwarf.loc[i] = DWARF_NULL_LOC; |
| |
| c->dwarf.loc[RBP] = rbp_loc; |
| c->dwarf.loc[RSP] = rsp_loc; |
| c->dwarf.loc[RIP] = rip_loc; |
| c->dwarf.ret_addr_column = RIP; |
| |
| if (!DWARF_IS_NULL_LOC (c->dwarf.loc[RBP])) |
| { |
| ret = dwarf_get (&c->dwarf, c->dwarf.loc[RIP], &c->dwarf.ip); |
| if (ret < 0) |
| return ret; |
| } |
| else |
| c->dwarf.ip = 0; |
| } |
| return (c->dwarf.ip == 0) ? 0 : 1; |
| } |