1//===-- lsan_mac.cpp ------------------------------------------------------===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8// 9// This file is a part of LeakSanitizer, a memory leak checker. 10// 11// Mac-specific details. 12//===----------------------------------------------------------------------===// 13 14#include "sanitizer_common/sanitizer_platform.h" 15#if SANITIZER_MAC 16 17#include "interception/interception.h" 18#include "lsan.h" 19#include "lsan_allocator.h" 20#include "lsan_thread.h" 21 22#include <pthread.h> 23 24namespace __lsan { 25// Support for the following functions from libdispatch on Mac OS: 26// dispatch_async_f() 27// dispatch_async() 28// dispatch_sync_f() 29// dispatch_sync() 30// dispatch_after_f() 31// dispatch_after() 32// dispatch_group_async_f() 33// dispatch_group_async() 34// TODO(glider): libdispatch API contains other functions that we don't support 35// yet. 36// 37// dispatch_sync() and dispatch_sync_f() are synchronous, although chances are 38// they can cause jobs to run on a thread different from the current one. 39// TODO(glider): if so, we need a test for this (otherwise we should remove 40// them). 41// 42// The following functions use dispatch_barrier_async_f() (which isn't a library 43// function but is exported) and are thus supported: 44// dispatch_source_set_cancel_handler_f() 45// dispatch_source_set_cancel_handler() 46// dispatch_source_set_event_handler_f() 47// dispatch_source_set_event_handler() 48// 49// The reference manual for Grand Central Dispatch is available at 50// http://developer.apple.com/library/mac/#documentation/Performance/Reference/GCD_libdispatch_Ref/Reference/reference.html 51// The implementation details are at 52// http://libdispatch.macosforge.org/trac/browser/trunk/src/queue.c 53 54typedef void *dispatch_group_t; 55typedef void *dispatch_queue_t; 56typedef void *dispatch_source_t; 57typedef u64 dispatch_time_t; 58typedef void (*dispatch_function_t)(void *block); 59typedef void *(*worker_t)(void *block); 60 61// A wrapper for the ObjC blocks used to support libdispatch. 62typedef struct { 63 void *block; 64 dispatch_function_t func; 65 u32 parent_tid; 66} lsan_block_context_t; 67 68ALWAYS_INLINE 69void lsan_register_worker_thread(int parent_tid) { 70 if (GetCurrentThread() == kInvalidTid) { 71 u32 tid = ThreadCreate(parent_tid, 0, true); 72 ThreadStart(tid, GetTid()); 73 SetCurrentThread(tid); 74 } 75} 76 77// For use by only those functions that allocated the context via 78// alloc_lsan_context(). 79extern "C" void lsan_dispatch_call_block_and_release(void *block) { 80 lsan_block_context_t *context = (lsan_block_context_t *)block; 81 VReport(2, 82 "lsan_dispatch_call_block_and_release(): " 83 "context: %p, pthread_self: %p\n", 84 block, pthread_self()); 85 lsan_register_worker_thread(context->parent_tid); 86 // Call the original dispatcher for the block. 87 context->func(context->block); 88 lsan_free(context); 89} 90 91} // namespace __lsan 92 93using namespace __lsan; 94 95// Wrap |ctxt| and |func| into an lsan_block_context_t. 96// The caller retains control of the allocated context. 97extern "C" lsan_block_context_t *alloc_lsan_context(void *ctxt, 98 dispatch_function_t func) { 99 GET_STACK_TRACE_THREAD; 100 lsan_block_context_t *lsan_ctxt = 101 (lsan_block_context_t *)lsan_malloc(sizeof(lsan_block_context_t), stack); 102 lsan_ctxt->block = ctxt; 103 lsan_ctxt->func = func; 104 lsan_ctxt->parent_tid = GetCurrentThread(); 105 return lsan_ctxt; 106} 107 108// Define interceptor for dispatch_*_f function with the three most common 109// parameters: dispatch_queue_t, context, dispatch_function_t. 110#define INTERCEPT_DISPATCH_X_F_3(dispatch_x_f) \ 111 INTERCEPTOR(void, dispatch_x_f, dispatch_queue_t dq, void *ctxt, \ 112 dispatch_function_t func) { \ 113 lsan_block_context_t *lsan_ctxt = alloc_lsan_context(ctxt, func); \ 114 return REAL(dispatch_x_f)(dq, (void *)lsan_ctxt, \ 115 lsan_dispatch_call_block_and_release); \ 116 } 117 118INTERCEPT_DISPATCH_X_F_3(dispatch_async_f) 119INTERCEPT_DISPATCH_X_F_3(dispatch_sync_f) 120INTERCEPT_DISPATCH_X_F_3(dispatch_barrier_async_f) 121 122INTERCEPTOR(void, dispatch_after_f, dispatch_time_t when, dispatch_queue_t dq, 123 void *ctxt, dispatch_function_t func) { 124 lsan_block_context_t *lsan_ctxt = alloc_lsan_context(ctxt, func); 125 return REAL(dispatch_after_f)(when, dq, (void *)lsan_ctxt, 126 lsan_dispatch_call_block_and_release); 127} 128 129INTERCEPTOR(void, dispatch_group_async_f, dispatch_group_t group, 130 dispatch_queue_t dq, void *ctxt, dispatch_function_t func) { 131 lsan_block_context_t *lsan_ctxt = alloc_lsan_context(ctxt, func); 132 REAL(dispatch_group_async_f) 133 (group, dq, (void *)lsan_ctxt, lsan_dispatch_call_block_and_release); 134} 135 136#if !defined(MISSING_BLOCKS_SUPPORT) 137extern "C" { 138void dispatch_async(dispatch_queue_t dq, void (^work)(void)); 139void dispatch_group_async(dispatch_group_t dg, dispatch_queue_t dq, 140 void (^work)(void)); 141void dispatch_after(dispatch_time_t when, dispatch_queue_t queue, 142 void (^work)(void)); 143void dispatch_source_set_cancel_handler(dispatch_source_t ds, 144 void (^work)(void)); 145void dispatch_source_set_event_handler(dispatch_source_t ds, 146 void (^work)(void)); 147} 148 149#define GET_LSAN_BLOCK(work) \ 150 void (^lsan_block)(void); \ 151 int parent_tid = GetCurrentThread(); \ 152 lsan_block = ^(void) { \ 153 lsan_register_worker_thread(parent_tid); \ 154 work(); \ 155 } 156 157INTERCEPTOR(void, dispatch_async, dispatch_queue_t dq, void (^work)(void)) { 158 GET_LSAN_BLOCK(work); 159 REAL(dispatch_async)(dq, lsan_block); 160} 161 162INTERCEPTOR(void, dispatch_group_async, dispatch_group_t dg, 163 dispatch_queue_t dq, void (^work)(void)) { 164 GET_LSAN_BLOCK(work); 165 REAL(dispatch_group_async)(dg, dq, lsan_block); 166} 167 168INTERCEPTOR(void, dispatch_after, dispatch_time_t when, dispatch_queue_t queue, 169 void (^work)(void)) { 170 GET_LSAN_BLOCK(work); 171 REAL(dispatch_after)(when, queue, lsan_block); 172} 173 174INTERCEPTOR(void, dispatch_source_set_cancel_handler, dispatch_source_t ds, 175 void (^work)(void)) { 176 if (!work) { 177 REAL(dispatch_source_set_cancel_handler)(ds, work); 178 return; 179 } 180 GET_LSAN_BLOCK(work); 181 REAL(dispatch_source_set_cancel_handler)(ds, lsan_block); 182} 183 184INTERCEPTOR(void, dispatch_source_set_event_handler, dispatch_source_t ds, 185 void (^work)(void)) { 186 GET_LSAN_BLOCK(work); 187 REAL(dispatch_source_set_event_handler)(ds, lsan_block); 188} 189#endif 190 191#endif // SANITIZER_MAC 192