1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include "lint.h" 30 #include "thr_uberdata.h" 31 #include "stack_unwind.h" 32 #include "reg_num.h" 33 #include <dlfcn.h> 34 35 /* 36 * Due to the subtle mysteries of the amd64 unwind interfaces, the 37 * "Canonical Frame Address" is 16 bytes higher in memory than the 38 * value of the frame pointer (%fp). 39 */ 40 #define CFA_ADJUST 16 41 42 /* ARGSUSED */ 43 static _Unwind_Reason_Code 44 posix_stop_func( 45 int version, 46 _Unwind_Action _Unwind_actions, 47 uint64_t exceptionClass, 48 struct _Unwind_Exception *exceptionObject, 49 struct _Unwind_Context *context, 50 void *func_arg) 51 { 52 __cleanup_t **headp = (__cleanup_t **)func_arg; 53 __cleanup_t *head; 54 uint64_t cfa; 55 56 /* 57 * If we have reached the origin of the stack, exit now. 58 */ 59 cfa = _Unwind_GetCFA(context); 60 if (cfa == 0 || _Unwind_GetGR(context, RET_ADD) == 0) { 61 _Unwind_DeleteException(exceptionObject); 62 _thrp_exit(); 63 thr_panic("posix_stop_func(): _thrp_exit() returned"); 64 } 65 66 /* 67 * Call all Posix cleanup handlers for this frame. 68 */ 69 while ((head = *headp) != NULL && 70 (caddr_t)cfa == head->fp + CFA_ADJUST) { 71 *headp = head->next; 72 (*head->func)(head->arg); 73 } 74 75 return (_URC_NO_REASON); 76 } 77 78 /* 79 * _ex_unwind() is provided by libCrun to perform stack unwinding 80 * and calling C++ destructors as needed, interleaved with calling 81 * Posix cleanup handlers along the way. If libCrun is not present 82 * we just need to call the Posix cleanup handlers. 83 */ 84 85 /* ARGSUSED */ 86 void 87 _thrp_unwind(void *dummy) 88 { 89 ulwp_t *self = curthread; 90 __cleanup_t **headp = &self->ul_clnup_hdr; 91 __cleanup_t *head; 92 void (*fptr)(_Unwind_Stop_Fn, void *); 93 94 /* Do this once per thread exit, not once per unwind frame */ 95 if (self->ul_ex_unwind == NULL && 96 (self->ul_ex_unwind = dlsym(RTLD_PROBE, "_ex_unwind")) == NULL) 97 self->ul_ex_unwind = (void *)-1; 98 99 if (self->ul_ex_unwind == (void *)-1) 100 fptr = NULL; 101 else 102 fptr = (void (*)())self->ul_ex_unwind; 103 104 /* 105 * Call _ex_unwind() if it is present (C++ loaded), 106 * else just call the Posix cleanup handlers. 107 */ 108 if (fptr != NULL) 109 (*fptr)(posix_stop_func, headp); 110 111 /* 112 * Call all remaining Posix cleanup handlers. 113 */ 114 while ((head = *headp) != NULL) { 115 *headp = head->next; 116 (*head->func)(head->arg); 117 } 118 119 _thrp_exit(); 120 thr_panic("_thrp_unwind(): _thrp_exit() returned"); 121 } 122