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_APPLE
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 (GetCurrentThreadId() == kInvalidTid) {
71 u32 tid = ThreadCreate(parent_tid, true);
72 ThreadStart(tid, GetTid());
73 }
74}
75
76// For use by only those functions that allocated the context via
77// alloc_lsan_context().
78extern "C" void lsan_dispatch_call_block_and_release(void *block) {
79 lsan_block_context_t *context = (lsan_block_context_t *)block;
80 VReport(2,
81 "lsan_dispatch_call_block_and_release(): "
82 "context: %p, pthread_self: %p\n",
83 block, (void*)pthread_self());
84 lsan_register_worker_thread(context->parent_tid);
85 // Call the original dispatcher for the block.
86 context->func(context->block);
87 lsan_free(context);
88}
89
90} // namespace __lsan
91
92using namespace __lsan;
93
94// Wrap |ctxt| and |func| into an lsan_block_context_t.
95// The caller retains control of the allocated context.
96extern "C" lsan_block_context_t *alloc_lsan_context(void *ctxt,
97 dispatch_function_t func) {
98 GET_STACK_TRACE_THREAD;
99 lsan_block_context_t *lsan_ctxt =
100 (lsan_block_context_t *)lsan_malloc(sizeof(lsan_block_context_t), stack);
101 lsan_ctxt->block = ctxt;
102 lsan_ctxt->func = func;
103 lsan_ctxt->parent_tid = GetCurrentThreadId();
104 return lsan_ctxt;
105}
106
107// Define interceptor for dispatch_*_f function with the three most common
108// parameters: dispatch_queue_t, context, dispatch_function_t.
109#define INTERCEPT_DISPATCH_X_F_3(dispatch_x_f) \
110 INTERCEPTOR(void, dispatch_x_f, dispatch_queue_t dq, void *ctxt, \
111 dispatch_function_t func) { \
112 lsan_block_context_t *lsan_ctxt = alloc_lsan_context(ctxt, func); \
113 return REAL(dispatch_x_f)(dq, (void *)lsan_ctxt, \
114 lsan_dispatch_call_block_and_release); \
115 }
116
117INTERCEPT_DISPATCH_X_F_3(dispatch_async_f)
118INTERCEPT_DISPATCH_X_F_3(dispatch_sync_f)
119INTERCEPT_DISPATCH_X_F_3(dispatch_barrier_async_f)
120
121INTERCEPTOR(void, dispatch_after_f, dispatch_time_t when, dispatch_queue_t dq,
122 void *ctxt, dispatch_function_t func) {
123 lsan_block_context_t *lsan_ctxt = alloc_lsan_context(ctxt, func);
124 return REAL(dispatch_after_f)(when, dq, (void *)lsan_ctxt,
125 lsan_dispatch_call_block_and_release);
126}
127
128INTERCEPTOR(void, dispatch_group_async_f, dispatch_group_t group,
129 dispatch_queue_t dq, void *ctxt, dispatch_function_t func) {
130 lsan_block_context_t *lsan_ctxt = alloc_lsan_context(ctxt, func);
131 REAL(dispatch_group_async_f)
132 (group, dq, (void *)lsan_ctxt, lsan_dispatch_call_block_and_release);
133}
134
135#if !defined(MISSING_BLOCKS_SUPPORT)
136extern "C" {
137void dispatch_async(dispatch_queue_t dq, void (^work)(void));
138void dispatch_group_async(dispatch_group_t dg, dispatch_queue_t dq,
139 void (^work)(void));
140void dispatch_after(dispatch_time_t when, dispatch_queue_t queue,
141 void (^work)(void));
142void dispatch_source_set_cancel_handler(dispatch_source_t ds,
143 void (^work)(void));
144void dispatch_source_set_event_handler(dispatch_source_t ds,
145 void (^work)(void));
146}
147
148# define GET_LSAN_BLOCK(work) \
149 void (^lsan_block)(void); \
150 int parent_tid = GetCurrentThreadId(); \
151 lsan_block = ^(void) { \
152 lsan_register_worker_thread(parent_tid); \
153 work(); \
154 }
155
156INTERCEPTOR(void, dispatch_async, dispatch_queue_t dq, void (^work)(void)) {
157 GET_LSAN_BLOCK(work);
158 REAL(dispatch_async)(dq, lsan_block);
159}
160
161INTERCEPTOR(void, dispatch_group_async, dispatch_group_t dg,
162 dispatch_queue_t dq, void (^work)(void)) {
163 GET_LSAN_BLOCK(work);
164 REAL(dispatch_group_async)(dg, dq, lsan_block);
165}
166
167INTERCEPTOR(void, dispatch_after, dispatch_time_t when, dispatch_queue_t queue,
168 void (^work)(void)) {
169 GET_LSAN_BLOCK(work);
170 REAL(dispatch_after)(when, queue, lsan_block);
171}
172
173INTERCEPTOR(void, dispatch_source_set_cancel_handler, dispatch_source_t ds,
174 void (^work)(void)) {
175 if (!work) {
176 REAL(dispatch_source_set_cancel_handler)(ds, work);
177 return;
178 }
179 GET_LSAN_BLOCK(work);
180 REAL(dispatch_source_set_cancel_handler)(ds, lsan_block);
181}
182
183INTERCEPTOR(void, dispatch_source_set_event_handler, dispatch_source_t ds,
184 void (^work)(void)) {
185 GET_LSAN_BLOCK(work);
186 REAL(dispatch_source_set_event_handler)(ds, lsan_block);
187}
188#endif
189
190#endif // SANITIZER_APPLE
191

source code of compiler-rt/lib/lsan/lsan_mac.cpp