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diff --git a/lib/lsan/lsan_common_mac.cpp b/lib/lsan/lsan_common_mac.cpp
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+//=-- lsan_common_mac.cpp -------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of LeakSanitizer.
+// Implementation of common leak checking functionality. Darwin-specific code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_platform.h"
+#include "sanitizer_common/sanitizer_libc.h"
+#include "lsan_common.h"
+
+#if CAN_SANITIZE_LEAKS && SANITIZER_MAC
+
+#include "sanitizer_common/sanitizer_allocator_internal.h"
+#include "lsan_allocator.h"
+
+#include <pthread.h>
+
+#include <mach/mach.h>
+
+// Only introduced in Mac OS X 10.9.
+#ifdef VM_MEMORY_OS_ALLOC_ONCE
+static const int kSanitizerVmMemoryOsAllocOnce = VM_MEMORY_OS_ALLOC_ONCE;
+#else
+static const int kSanitizerVmMemoryOsAllocOnce = 73;
+#endif
+
+namespace __lsan {
+
+typedef struct {
+ int disable_counter;
+ u32 current_thread_id;
+ AllocatorCache cache;
+} thread_local_data_t;
+
+static pthread_key_t key;
+static pthread_once_t key_once = PTHREAD_ONCE_INIT;
+
+// The main thread destructor requires the current thread id,
+// so we can't destroy it until it's been used and reset to invalid tid
+void restore_tid_data(void *ptr) {
+ thread_local_data_t *data = (thread_local_data_t *)ptr;
+ if (data->current_thread_id != kInvalidTid)
+ pthread_setspecific(key, data);
+}
+
+static void make_tls_key() {
+ CHECK_EQ(pthread_key_create(&key, restore_tid_data), 0);
+}
+
+static thread_local_data_t *get_tls_val(bool alloc) {
+ pthread_once(&key_once, make_tls_key);
+
+ thread_local_data_t *ptr = (thread_local_data_t *)pthread_getspecific(key);
+ if (ptr == NULL && alloc) {
+ ptr = (thread_local_data_t *)InternalAlloc(sizeof(*ptr));
+ ptr->disable_counter = 0;
+ ptr->current_thread_id = kInvalidTid;
+ ptr->cache = AllocatorCache();
+ pthread_setspecific(key, ptr);
+ }
+
+ return ptr;
+}
+
+bool DisabledInThisThread() {
+ thread_local_data_t *data = get_tls_val(false);
+ return data ? data->disable_counter > 0 : false;
+}
+
+void DisableInThisThread() { ++get_tls_val(true)->disable_counter; }
+
+void EnableInThisThread() {
+ int *disable_counter = &get_tls_val(true)->disable_counter;
+ if (*disable_counter == 0) {
+ DisableCounterUnderflow();
+ }
+ --*disable_counter;
+}
+
+u32 GetCurrentThread() {
+ thread_local_data_t *data = get_tls_val(false);
+ return data ? data->current_thread_id : kInvalidTid;
+}
+
+void SetCurrentThread(u32 tid) { get_tls_val(true)->current_thread_id = tid; }
+
+AllocatorCache *GetAllocatorCache() { return &get_tls_val(true)->cache; }
+
+LoadedModule *GetLinker() { return nullptr; }
+
+// Required on Linux for initialization of TLS behavior, but should not be
+// required on Darwin.
+void InitializePlatformSpecificModules() {}
+
+// Sections which can't contain contain global pointers. This list errs on the
+// side of caution to avoid false positives, at the expense of performance.
+//
+// Other potentially safe sections include:
+// __all_image_info, __crash_info, __const, __got, __interpose, __objc_msg_break
+//
+// Sections which definitely cannot be included here are:
+// __objc_data, __objc_const, __data, __bss, __common, __thread_data,
+// __thread_bss, __thread_vars, __objc_opt_rw, __objc_opt_ptrs
+static const char *kSkippedSecNames[] = {
+ "__cfstring", "__la_symbol_ptr", "__mod_init_func",
+ "__mod_term_func", "__nl_symbol_ptr", "__objc_classlist",
+ "__objc_classrefs", "__objc_imageinfo", "__objc_nlclslist",
+ "__objc_protolist", "__objc_selrefs", "__objc_superrefs"};
+
+// Scans global variables for heap pointers.
+void ProcessGlobalRegions(Frontier *frontier) {
+ for (auto name : kSkippedSecNames)
+ CHECK(internal_strnlen(name, kMaxSegName + 1) <= kMaxSegName);
+
+ MemoryMappingLayout memory_mapping(false);
+ InternalMmapVector<LoadedModule> modules;
+ modules.reserve(128);
+ memory_mapping.DumpListOfModules(&modules);
+ for (uptr i = 0; i < modules.size(); ++i) {
+ // Even when global scanning is disabled, we still need to scan
+ // system libraries for stashed pointers
+ if (!flags()->use_globals && modules[i].instrumented()) continue;
+
+ for (const __sanitizer::LoadedModule::AddressRange &range :
+ modules[i].ranges()) {
+ // Sections storing global variables are writable and non-executable
+ if (range.executable || !range.writable) continue;
+
+ for (auto name : kSkippedSecNames) {
+ if (!internal_strcmp(range.name, name)) continue;
+ }
+
+ ScanGlobalRange(range.beg, range.end, frontier);
+ }
+ }
+}
+
+void ProcessPlatformSpecificAllocations(Frontier *frontier) {
+ unsigned depth = 1;
+ vm_size_t size = 0;
+ vm_address_t address = 0;
+ kern_return_t err = KERN_SUCCESS;
+ mach_msg_type_number_t count = VM_REGION_SUBMAP_INFO_COUNT_64;
+
+ InternalMmapVector<RootRegion> const *root_regions = GetRootRegions();
+
+ while (err == KERN_SUCCESS) {
+ struct vm_region_submap_info_64 info;
+ err = vm_region_recurse_64(mach_task_self(), &address, &size, &depth,
+ (vm_region_info_t)&info, &count);
+
+ uptr end_address = address + size;
+
+ // libxpc stashes some pointers in the Kernel Alloc Once page,
+ // make sure not to report those as leaks.
+ if (info.user_tag == kSanitizerVmMemoryOsAllocOnce) {
+ ScanRangeForPointers(address, end_address, frontier, "GLOBAL",
+ kReachable);
+
+ // Recursing over the full memory map is very slow, break out
+ // early if we don't need the full iteration.
+ if (!flags()->use_root_regions || !root_regions->size())
+ break;
+ }
+
+ // This additional root region scan is required on Darwin in order to
+ // detect root regions contained within mmap'd memory regions, because
+ // the Darwin implementation of sanitizer_procmaps traverses images
+ // as loaded by dyld, and not the complete set of all memory regions.
+ //
+ // TODO(fjricci) - remove this once sanitizer_procmaps_mac has the same
+ // behavior as sanitizer_procmaps_linux and traverses all memory regions
+ if (flags()->use_root_regions) {
+ for (uptr i = 0; i < root_regions->size(); i++) {
+ ScanRootRegion(frontier, (*root_regions)[i], address, end_address,
+ info.protection & kProtectionRead);
+ }
+ }
+
+ address = end_address;
+ }
+}
+
+// On darwin, we can intercept _exit gracefully, and return a failing exit code
+// if required at that point. Calling Die() here is undefined behavior and
+// causes rare race conditions.
+void HandleLeaks() {}
+
+void LockStuffAndStopTheWorld(StopTheWorldCallback callback, void *argument) {
+ LockThreadRegistry();
+ LockAllocator();
+ StopTheWorld(callback, argument);
+ UnlockAllocator();
+ UnlockThreadRegistry();
+}
+
+} // namespace __lsan
+
+#endif // CAN_SANITIZE_LEAKS && SANITIZER_MAC