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--- dyld/dyld-732.8/src/threadLocalVariables.c
+++ /dev/null
@@ -1,432 +0,0 @@
-/* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
- *
- * Copyright (c) 2010 Apple Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-
-#include <stdlib.h>
-#include <stdint.h>
-#include <string.h>
-#include <stddef.h>
-#include <stdio.h>
-#include <pthread.h>
-#include <Block.h>
-#include <malloc/malloc.h>
-#include <mach-o/loader.h>
-#include <libkern/OSAtomic.h>
-
-#include <mach-o/dyld_priv.h>
-
-
-#if __LP64__
- typedef struct mach_header_64 macho_header;
- #define LC_SEGMENT_COMMAND LC_SEGMENT_64
- typedef struct segment_command_64 macho_segment_command;
- typedef struct section_64 macho_section;
-#else
- typedef struct mach_header macho_header;
- #define LC_SEGMENT_COMMAND LC_SEGMENT
- typedef struct segment_command macho_segment_command;
- typedef struct section macho_section;
-#endif
-
-
-typedef void (*TermFunc)(void*);
-
-
-
-#if __has_feature(tls) || __arm64__ || __arm__
-
-//
-// Info about thread-local variable storage.
-//
-typedef struct {
- size_t info_size; // sizeof(dyld_tlv_info)
- void * tlv_addr; // Base address of TLV storage
- size_t tlv_size; // Byte size of TLV storage
-} dyld_tlv_info;
-
-
-struct TLVDescriptor
-{
- void* (*thunk)(struct TLVDescriptor*);
- unsigned long key;
- unsigned long offset;
-};
-typedef struct TLVDescriptor TLVDescriptor;
-
-
-// implemented in assembly
-extern void* tlv_get_addr(TLVDescriptor*);
-
-struct TLVImageInfo
-{
- pthread_key_t key;
- const struct mach_header* mh;
-};
-typedef struct TLVImageInfo TLVImageInfo;
-
-static TLVImageInfo* tlv_live_images = NULL;
-static unsigned int tlv_live_image_alloc_count = 0;
-static unsigned int tlv_live_image_used_count = 0;
-static pthread_mutex_t tlv_live_image_lock = PTHREAD_MUTEX_INITIALIZER;
-
-static void tlv_set_key_for_image(const struct mach_header* mh, pthread_key_t key)
-{
- pthread_mutex_lock(&tlv_live_image_lock);
- if ( tlv_live_image_used_count == tlv_live_image_alloc_count ) {
- unsigned int newCount = (tlv_live_images == NULL) ? 8 : 2*tlv_live_image_alloc_count;
- struct TLVImageInfo* newBuffer = malloc(sizeof(TLVImageInfo)*newCount);
- if ( tlv_live_images != NULL ) {
- memcpy(newBuffer, tlv_live_images, sizeof(TLVImageInfo)*tlv_live_image_used_count);
- free(tlv_live_images);
- }
- tlv_live_images = newBuffer;
- tlv_live_image_alloc_count = newCount;
- }
- tlv_live_images[tlv_live_image_used_count].key = key;
- tlv_live_images[tlv_live_image_used_count].mh = mh;
- ++tlv_live_image_used_count;
- pthread_mutex_unlock(&tlv_live_image_lock);
-}
-
-static const struct mach_header* tlv_get_image_for_key(pthread_key_t key)
-{
- const struct mach_header* result = NULL;
- pthread_mutex_lock(&tlv_live_image_lock);
- for(unsigned int i=0; i < tlv_live_image_used_count; ++i) {
- if ( tlv_live_images[i].key == key ) {
- result = tlv_live_images[i].mh;
- break;
- }
- }
- pthread_mutex_unlock(&tlv_live_image_lock);
- return result;
-}
-
-
-// called lazily when TLV is first accessed
-__attribute__((visibility("hidden")))
-void* tlv_allocate_and_initialize_for_key(pthread_key_t key)
-{
- const struct mach_header* mh = tlv_get_image_for_key(key);
- if ( mh == NULL )
- return NULL; // if data structures are screwed up, don't crash
-
- // first pass, find size and template
- uint8_t* start = NULL;
- unsigned long size = 0;
- intptr_t slide = 0;
- bool slideComputed = false;
- bool hasInitializers = false;
- const uint32_t cmd_count = mh->ncmds;
- const struct load_command* const cmds = (struct load_command*)(((uint8_t*)mh) + sizeof(macho_header));
- const struct load_command* cmd = cmds;
- for (uint32_t i = 0; i < cmd_count; ++i) {
- if ( cmd->cmd == LC_SEGMENT_COMMAND) {
- const macho_segment_command* seg = (macho_segment_command*)cmd;
- if ( !slideComputed && (seg->filesize != 0) ) {
- slide = (uintptr_t)mh - seg->vmaddr;
- slideComputed = true;
- }
- const macho_section* const sectionsStart = (macho_section*)((char*)seg + sizeof(macho_segment_command));
- const macho_section* const sectionsEnd = §ionsStart[seg->nsects];
- for (const macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
- switch ( sect->flags & SECTION_TYPE ) {
- case S_THREAD_LOCAL_INIT_FUNCTION_POINTERS:
- hasInitializers = true;
- break;
- case S_THREAD_LOCAL_ZEROFILL:
- case S_THREAD_LOCAL_REGULAR:
- if ( start == NULL ) {
- // first of N contiguous TLV template sections, record as if this was only section
- start = (uint8_t*)(sect->addr + slide);
- size = sect->size;
- }
- else {
- // non-first of N contiguous TLV template sections, accumlate values
- const uint8_t* newEnd = (uint8_t*)(sect->addr + slide + sect->size);
- size = newEnd - start;
- }
- break;
- }
- }
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
- // no thread local storage in image: should never happen
- if ( size == 0 )
- return NULL;
-
- // allocate buffer and fill with template
- void* buffer = malloc(size);
- memcpy(buffer, start, size);
-
- // set this thread's value for key to be the new buffer.
- pthread_setspecific(key, buffer);
-
- // second pass, run initializers
- if ( hasInitializers ) {
- cmd = cmds;
- for (uint32_t i = 0; i < cmd_count; ++i) {
- if ( cmd->cmd == LC_SEGMENT_COMMAND) {
- const macho_segment_command* seg = (macho_segment_command*)cmd;
- const macho_section* const sectionsStart = (macho_section*)((char*)seg + sizeof(macho_segment_command));
- const macho_section* const sectionsEnd = §ionsStart[seg->nsects];
- for (const macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
- if ( (sect->flags & SECTION_TYPE) == S_THREAD_LOCAL_INIT_FUNCTION_POINTERS ) {
- typedef void (*InitFunc)(void);
- InitFunc* funcs = (InitFunc*)(sect->addr + slide);
- const size_t count = sect->size / sizeof(uintptr_t);
- for (size_t j=count; j > 0; --j) {
- InitFunc func = funcs[j-1];
- func();
- }
- }
- }
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
- }
- return buffer;
-}
-
-
-// pthread destructor for TLV storage
-static void
-tlv_free(void *storage)
-{
- free(storage);
-}
-
-
-// called when image is loaded
-static void tlv_initialize_descriptors(const struct mach_header* mh)
-{
- pthread_key_t key = 0;
- intptr_t slide = 0;
- bool slideComputed = false;
- const uint32_t cmd_count = mh->ncmds;
- const struct load_command* const cmds = (struct load_command*)(((uint8_t*)mh) + sizeof(macho_header));
- const struct load_command* cmd = cmds;
- for (uint32_t i = 0; i < cmd_count; ++i) {
- if ( cmd->cmd == LC_SEGMENT_COMMAND) {
- const macho_segment_command* seg = (macho_segment_command*)cmd;
- if ( !slideComputed && (seg->filesize != 0) ) {
- slide = (uintptr_t)mh - seg->vmaddr;
- slideComputed = true;
- }
- const macho_section* const sectionsStart = (macho_section*)((char*)seg + sizeof(macho_segment_command));
- const macho_section* const sectionsEnd = §ionsStart[seg->nsects];
- for (const macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
- if ( (sect->flags & SECTION_TYPE) == S_THREAD_LOCAL_VARIABLES ) {
- if ( sect->size != 0 ) {
- // allocate pthread key when we first discover this image has TLVs
- if ( key == 0 ) {
- int result = pthread_key_create(&key, &tlv_free);
- if ( result != 0 )
- abort();
- tlv_set_key_for_image(mh, key);
- }
- // initialize each descriptor
- TLVDescriptor* start = (TLVDescriptor*)(sect->addr + slide);
- TLVDescriptor* end = (TLVDescriptor*)(sect->addr + sect->size + slide);
- for (TLVDescriptor* d=start; d < end; ++d) {
- d->thunk = tlv_get_addr;
- d->key = key;
- //d->offset = d->offset; // offset unchanged
- }
- }
- }
- }
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
-}
-
-
-static void tlv_load_notification(const struct mach_header* mh, intptr_t slide)
-{
- // This is called on all images, even those without TLVs. So we want this to be fast.
- // The linker sets MH_HAS_TLV_DESCRIPTORS so we don't have to search images just to find the don't have TLVs.
- if ( mh->flags & MH_HAS_TLV_DESCRIPTORS )
- tlv_initialize_descriptors(mh);
-}
-
-
-//
-// thread_local terminators
-//
-// C++ 0x allows thread_local C++ objects which have constructors run
-// on the thread before any use of the object and the object's destructor
-// is run on the thread when the thread terminates.
-//
-// To support this libdyld gets a pthread key early in process start up and
-// uses tlv_finalize and the key's destructor function. This key must be
-// allocated before any thread local variables are instantiated because when
-// a thread is terminated, the pthread package runs the destructor function
-// on each key's storage values in key allocation order. Since we want
-// C++ objects to be destructred before they are deallocated, we need the
-// destructor key to come before the deallocation key.
-//
-
-struct TLVTerminatorListEntry
-{
- TermFunc termFunc;
- void* objAddr;
-};
-
-struct TLVTerminatorList
-{
- uint32_t allocCount;
- uint32_t useCount;
- struct TLVTerminatorListEntry entries[1]; // variable length
-};
-
-
-static pthread_key_t tlv_terminators_key = 0;
-
-void _tlv_atexit(TermFunc func, void* objAddr)
-{
- // NOTE: this does not need locks because it only operates on current thread data
- struct TLVTerminatorList* list = (struct TLVTerminatorList*)pthread_getspecific(tlv_terminators_key);
- if ( list == NULL ) {
- // handle first allocation
- list = (struct TLVTerminatorList*)malloc(offsetof(struct TLVTerminatorList, entries[1]));
- list->allocCount = 1;
- list->useCount = 1;
- list->entries[0].termFunc = func;
- list->entries[0].objAddr = objAddr;
- pthread_setspecific(tlv_terminators_key, list);
- }
- else {
- if ( list->useCount == list->allocCount ) {
- // handle resizing allocation
- uint32_t newAllocCount = list->allocCount * 2;
- size_t newAllocSize = offsetof(struct TLVTerminatorList, entries[newAllocCount]);
- struct TLVTerminatorList* newlist = (struct TLVTerminatorList*)malloc(newAllocSize);
- newlist->allocCount = newAllocCount;
- newlist->useCount = list->useCount;
- for(uint32_t i=0; i < list->useCount; ++i)
- newlist->entries[i] = list->entries[i];
- pthread_setspecific(tlv_terminators_key, newlist);
- free(list);
- list = newlist;
- }
- // handle appending new entry
- list->entries[list->useCount].termFunc = func;
- list->entries[list->useCount].objAddr = objAddr;
- list->useCount += 1;
- }
-}
-
-static void tlv_finalize_list(struct TLVTerminatorList* list) {
- // destroy in reverse order of construction
- for(uint32_t i=list->useCount; i > 0 ; --i) {
- struct TLVTerminatorListEntry* entry = &list->entries[i-1];
- if ( entry->termFunc != NULL ) {
- (*entry->termFunc)(entry->objAddr);
- }
-
- // If a new tlv was added via tlv_atexit, then we need to immediately
- // destroy it
- struct TLVTerminatorList* newlist = (struct TLVTerminatorList*)pthread_getspecific(tlv_terminators_key);
- if ( newlist != NULL ) {
- // Set the list to NULL so that if yet another tlv is registered, we put it in a new list
- pthread_setspecific(tlv_terminators_key, NULL);
- tlv_finalize_list(newlist);
- }
- }
- free(list);
-}
-
-// called by pthreads when the current thread is going away and
-// _tlv_atexit() has been called on the thread.
-static void tlv_finalize(void* storage)
-{
- // Note, on entry to this function, _tlv_exit set the list to NULL. libpthread
- // also set it to NULL before calling us. If new thread locals are added to our
- // tlv_terminators_key, then they will be on a new list, but the list we have here
- // is one we own and need to destroy it
- tlv_finalize_list((struct TLVTerminatorList*)storage);
-}
-
-// <rdar://problem/13741816>
-// called by exit() before it calls cxa_finalize() so that thread_local
-// objects are destroyed before global objects.
-// Note this is only called on macOS, and by libc.
-// iOS only destroys tlv's when each thread is destroyed and libpthread calls
-// tlv_finalize as that is the pointer we provided when we created the key
-void _tlv_exit()
-{
- void* termFuncs = pthread_getspecific(tlv_terminators_key);
- if ( termFuncs != NULL ) {
- // Clear the value so that calls to tlv_atexit during tlv_finalize
- // will go on to a new list to destroy.
- pthread_setspecific(tlv_terminators_key, NULL);
- tlv_finalize(termFuncs);
- }
-}
-
-
-__attribute__((visibility("hidden")))
-void tlv_initializer()
-{
- // create pthread key to handle thread_local destructors
- // NOTE: this key must be allocated before any keys for TLV
- // so that _pthread_tsd_cleanup will run destructors before deallocation
- (void)pthread_key_create(&tlv_terminators_key, &tlv_finalize);
-
- // register with dyld for notification when images are loaded
- _dyld_register_func_for_add_image(tlv_load_notification);
-
-}
-
-
-// linked images with TLV have references to this symbol, but it is never used at runtime
-void _tlv_bootstrap()
-{
- abort();
-}
-
-
-
-#else
-
-void _tlv_exit()
-{
-}
-
-void _tlv_atexit(TermFunc func, void* objAddr)
-{
-}
-
-__attribute__((visibility("hidden")))
-void tlv_initializer()
-{
-}
-
-
-
-#endif // __has_feature(tls)
-
-