/* libunwind - a platform-independent unwind library Copyright (C) 2002-2004 Hewlett-Packard Co Contributed by David Mosberger-Tang 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 "offsets.h" PROTECTED int unw_is_signal_frame (unw_cursor_t *cursor) { struct cursor *c = (struct cursor *) cursor; unw_word_t w0, w1, ip; unw_addr_space_t as; unw_accessors_t *a; void *arg; int ret; as = c->dwarf.as; a = unw_get_accessors (as); arg = c->dwarf.as_arg; /* Check if EIP points at sigreturn() sequence. On Linux, this is: __restore: 0x58 pop %eax 0xb8 0x77 0x00 0x00 0x00 movl 0x77,%eax 0xcd 0x80 int 0x80 without SA_SIGINFO, and __restore_rt: 0xb8 0xad 0x00 0x00 0x00 movl 0xad,%eax 0xcd 0x80 int 0x80 0x00 if SA_SIGINFO is specified. */ ip = c->dwarf.ip; if ((ret = (*a->access_mem) (as, ip, &w0, 0, arg)) < 0 || (ret = (*a->access_mem) (as, ip + 4, &w1, 0, arg)) < 0) return ret; ret = ((w0 == 0x0077b858 && w1 == 0x80cd0000) || (w0 == 0x0000adb8 && (w1 & 0xffffff) == 0x80cd00)); Debug (16, "returning %d\n", ret); return ret; } PROTECTED int unw_handle_signal_frame (unw_cursor_t *cursor) { struct cursor *c = (struct cursor *) cursor; int ret; /* c->esp points at the arguments to the handler. Without SA_SIGINFO, the arguments consist of a signal number followed by a struct sigcontext. With SA_SIGINFO, the arguments consist a signal number, a siginfo *, and a ucontext *. */ unw_word_t sc_addr; unw_word_t siginfo_ptr_addr = c->dwarf.cfa + 4; unw_word_t sigcontext_ptr_addr = c->dwarf.cfa + 8; unw_word_t siginfo_ptr, sigcontext_ptr; struct dwarf_loc esp_loc, siginfo_ptr_loc, sigcontext_ptr_loc; siginfo_ptr_loc = DWARF_LOC (siginfo_ptr_addr, 0); sigcontext_ptr_loc = DWARF_LOC (sigcontext_ptr_addr, 0); ret = (dwarf_get (&c->dwarf, siginfo_ptr_loc, &siginfo_ptr) | dwarf_get (&c->dwarf, sigcontext_ptr_loc, &sigcontext_ptr)); if (ret < 0) { Debug (2, "returning 0\n"); return 0; } if (siginfo_ptr < c->dwarf.cfa || siginfo_ptr > c->dwarf.cfa + 256 || sigcontext_ptr < c->dwarf.cfa || sigcontext_ptr > c->dwarf.cfa + 256) { /* Not plausible for SA_SIGINFO signal */ c->sigcontext_format = X86_SCF_LINUX_SIGFRAME; c->sigcontext_addr = sc_addr = c->dwarf.cfa + 4; } else { /* If SA_SIGINFO were not specified, we actually read various segment pointers instead. We believe that at least fs and _fsh are always zero for linux, so it is not just unlikely, but impossible that we would end up here. */ c->sigcontext_format = X86_SCF_LINUX_RT_SIGFRAME; c->sigcontext_addr = sigcontext_ptr; sc_addr = sigcontext_ptr + LINUX_UC_MCONTEXT_OFF; } esp_loc = DWARF_LOC (sc_addr + LINUX_SC_ESP_OFF, 0); ret = dwarf_get (&c->dwarf, esp_loc, &c->dwarf.cfa); if (ret < 0) { Debug (2, "returning 0\n"); return 0; } c->dwarf.loc[EAX] = DWARF_LOC (sc_addr + LINUX_SC_EAX_OFF, 0); c->dwarf.loc[ECX] = DWARF_LOC (sc_addr + LINUX_SC_ECX_OFF, 0); c->dwarf.loc[EDX] = DWARF_LOC (sc_addr + LINUX_SC_EDX_OFF, 0); c->dwarf.loc[EBX] = DWARF_LOC (sc_addr + LINUX_SC_EBX_OFF, 0); c->dwarf.loc[EBP] = DWARF_LOC (sc_addr + LINUX_SC_EBP_OFF, 0); c->dwarf.loc[ESI] = DWARF_LOC (sc_addr + LINUX_SC_ESI_OFF, 0); c->dwarf.loc[EDI] = DWARF_LOC (sc_addr + LINUX_SC_EDI_OFF, 0); c->dwarf.loc[EFLAGS] = DWARF_NULL_LOC; c->dwarf.loc[TRAPNO] = DWARF_NULL_LOC; c->dwarf.loc[ST0] = DWARF_NULL_LOC; c->dwarf.loc[EIP] = DWARF_LOC (sc_addr + LINUX_SC_EIP_OFF, 0); c->dwarf.loc[ESP] = DWARF_LOC (sc_addr + LINUX_SC_ESP_OFF, 0); return 0; } HIDDEN dwarf_loc_t x86_get_scratch_loc (struct cursor *c, unw_regnum_t reg) { unw_word_t addr = c->sigcontext_addr, fpstate_addr, off; int ret, is_fpstate = 0; switch (c->sigcontext_format) { case X86_SCF_NONE: return DWARF_REG_LOC (&c->dwarf, reg); case X86_SCF_LINUX_SIGFRAME: break; case X86_SCF_LINUX_RT_SIGFRAME: addr += LINUX_UC_MCONTEXT_OFF; break; } switch (reg) { case UNW_X86_GS: off = LINUX_SC_GS_OFF; break; case UNW_X86_FS: off = LINUX_SC_FS_OFF; break; case UNW_X86_ES: off = LINUX_SC_ES_OFF; break; case UNW_X86_DS: off = LINUX_SC_DS_OFF; break; case UNW_X86_EDI: off = LINUX_SC_EDI_OFF; break; case UNW_X86_ESI: off = LINUX_SC_ESI_OFF; break; case UNW_X86_EBP: off = LINUX_SC_EBP_OFF; break; case UNW_X86_ESP: off = LINUX_SC_ESP_OFF; break; case UNW_X86_EBX: off = LINUX_SC_EBX_OFF; break; case UNW_X86_EDX: off = LINUX_SC_EDX_OFF; break; case UNW_X86_ECX: off = LINUX_SC_ECX_OFF; break; case UNW_X86_EAX: off = LINUX_SC_EAX_OFF; break; case UNW_X86_TRAPNO: off = LINUX_SC_TRAPNO_OFF; break; case UNW_X86_EIP: off = LINUX_SC_EIP_OFF; break; case UNW_X86_CS: off = LINUX_SC_CS_OFF; break; case UNW_X86_EFLAGS: off = LINUX_SC_EFLAGS_OFF; break; case UNW_X86_SS: off = LINUX_SC_SS_OFF; break; /* The following is probably not correct for all possible cases. Somebody who understands this better should review this for correctness. */ case UNW_X86_FCW: is_fpstate = 1; off = LINUX_FPSTATE_CW_OFF; break; case UNW_X86_FSW: is_fpstate = 1; off = LINUX_FPSTATE_SW_OFF; break; case UNW_X86_FTW: is_fpstate = 1; off = LINUX_FPSTATE_TAG_OFF; break; case UNW_X86_FCS: is_fpstate = 1; off = LINUX_FPSTATE_CSSEL_OFF; break; case UNW_X86_FIP: is_fpstate = 1; off = LINUX_FPSTATE_IPOFF_OFF; break; case UNW_X86_FEA: is_fpstate = 1; off = LINUX_FPSTATE_DATAOFF_OFF; break; case UNW_X86_FDS: is_fpstate = 1; off = LINUX_FPSTATE_DATASEL_OFF; break; case UNW_X86_MXCSR: is_fpstate = 1; off = LINUX_FPSTATE_MXCSR_OFF; break; /* stacked fp registers */ case UNW_X86_ST0: case UNW_X86_ST1: case UNW_X86_ST2: case UNW_X86_ST3: case UNW_X86_ST4: case UNW_X86_ST5: case UNW_X86_ST6: case UNW_X86_ST7: is_fpstate = 1; off = LINUX_FPSTATE_ST0_OFF + 10*(reg - UNW_X86_ST0); break; /* SSE fp registers */ case UNW_X86_XMM0_lo: case UNW_X86_XMM0_hi: case UNW_X86_XMM1_lo: case UNW_X86_XMM1_hi: case UNW_X86_XMM2_lo: case UNW_X86_XMM2_hi: case UNW_X86_XMM3_lo: case UNW_X86_XMM3_hi: case UNW_X86_XMM4_lo: case UNW_X86_XMM4_hi: case UNW_X86_XMM5_lo: case UNW_X86_XMM5_hi: case UNW_X86_XMM6_lo: case UNW_X86_XMM6_hi: case UNW_X86_XMM7_lo: case UNW_X86_XMM7_hi: is_fpstate = 1; off = LINUX_FPSTATE_XMM0_OFF + 8*(reg - UNW_X86_XMM0_lo); break; case UNW_X86_XMM0: case UNW_X86_XMM1: case UNW_X86_XMM2: case UNW_X86_XMM3: case UNW_X86_XMM4: case UNW_X86_XMM5: case UNW_X86_XMM6: case UNW_X86_XMM7: is_fpstate = 1; off = LINUX_FPSTATE_XMM0_OFF + 16*(reg - UNW_X86_XMM0); break; case UNW_X86_FOP: case UNW_X86_TSS: case UNW_X86_LDT: default: return DWARF_REG_LOC (&c->dwarf, reg); } if (is_fpstate) { if ((ret = dwarf_get (&c->dwarf, DWARF_MEM_LOC (&c->dwarf, addr + LINUX_SC_FPSTATE_OFF), &fpstate_addr)) < 0) return DWARF_NULL_LOC; if (!fpstate_addr) return DWARF_NULL_LOC; return DWARF_MEM_LOC (c, fpstate_addr + off); } else return DWARF_MEM_LOC (c, addr + off); }