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src/dyld_process_info.cpp /dev/null dyld-640.2
--- /dev/null
+++ dyld/dyld-640.2/src/dyld_process_info.cpp
@@ -0,0 +1,753 @@
+/* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
+ *
+ * Copyright (c) 2016 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 <string.h>
+#include <limits.h>
+#include <stdio.h>
+#include <libproc.h>
+#include <sys/param.h>
+#include <mach/shared_region.h>
+#include <mach/mach_vm.h>
+#include <mach/vm_region.h>
+#include <libkern/OSAtomic.h>
+
+#include "dyld_process_info.h"
+#include "dyld_process_info_internal.h"
+#include "dyld_images.h"
+#include "dyld_priv.h"
+
+#include "Tracing.h"
+
+// this was in dyld_priv.h but it is no longer exported
+extern "C" {
+    const struct dyld_all_image_infos* _dyld_get_all_image_infos();
+}
+
+RemoteBuffer::RemoteBuffer() : _localAddress(0), _size(0) {}
+bool RemoteBuffer::map(task_t task, mach_vm_address_t remote_address, bool shared) {
+    vm_prot_t cur_protection = VM_PROT_NONE;
+    vm_prot_t max_protection = VM_PROT_NONE;
+    if (_size == 0) {
+        _kr = KERN_NO_SPACE;
+        return false;
+    }
+    _localAddress = 0;
+    _kr = mach_vm_remap(mach_task_self(),
+                        &_localAddress,
+                        _size,
+                        0,  // mask
+                        VM_FLAGS_ANYWHERE | VM_FLAGS_RETURN_DATA_ADDR | (shared ? 0 : VM_FLAGS_RESILIENT_CODESIGN),
+                        task,
+                        remote_address,
+                        !shared,
+                        &cur_protection,
+                        &max_protection,
+                        VM_INHERIT_NONE);
+    dyld3::kdebug_trace_dyld_marker(DBG_DYLD_DEBUGGING_VM_REMAP, _localAddress, (uint64_t)_size, _kr, remote_address);
+    if (shared && (cur_protection != (VM_PROT_READ|VM_PROT_WRITE))) {
+        if (_kr == KERN_SUCCESS && _localAddress != 0) {
+            _kr = vm_deallocate(mach_task_self(), _localAddress, _size);
+            dyld3::kdebug_trace_dyld_marker(DBG_DYLD_DEBUGGING_VM_UNMAP, _localAddress, (uint64_t)_size, _kr, 0);
+        }
+        _localAddress = 0;
+        _kr = KERN_PROTECTION_FAILURE;
+    }
+    return (_kr == KERN_SUCCESS);
+}
+
+RemoteBuffer::RemoteBuffer(task_t task, mach_vm_address_t remote_address, size_t remote_size, bool shared, bool allow_truncation)
+        : _localAddress(0), _size(remote_size), _kr(KERN_SUCCESS) {
+    // Try the initial map
+    if (map(task, remote_address, shared)) return;
+    // It failed, try to calculate the largest size that can fit in the same page as the remote_address
+    uint64_t newSize = PAGE_SIZE - remote_address%PAGE_SIZE;;
+    // If truncation is allowed and the newSize is different than the original size try that
+    if (!allow_truncation && newSize != _size) return;
+    _size = newSize;
+    if (map(task, remote_address, shared)) return;
+    // That did not work, null out the buffer
+    _size = 0;
+    _localAddress = 0;
+}
+RemoteBuffer::~RemoteBuffer() {
+    if (_localAddress) {
+        _kr = vm_deallocate(mach_task_self(), _localAddress, _size);
+        dyld3::kdebug_trace_dyld_marker(DBG_DYLD_DEBUGGING_VM_UNMAP, _localAddress, (uint64_t)_size, _kr, 0);
+    }
+}
+void *RemoteBuffer::getLocalAddress() { return (void *)_localAddress; }
+size_t RemoteBuffer::getSize() { return _size; }
+kern_return_t RemoteBuffer::getKernelReturn() { return _kr; }
+
+void withRemoteBuffer(task_t task, mach_vm_address_t remote_address, size_t remote_size, bool shared, bool allow_truncation, kern_return_t *kr, void (^block)(void *buffer, size_t size)) {
+    kern_return_t krSink = KERN_SUCCESS;
+    if (kr == nullptr) {
+        kr = &krSink;
+    }
+    RemoteBuffer buffer(task, remote_address, remote_size, shared, allow_truncation);
+    *kr = buffer.getKernelReturn();
+    if (*kr == KERN_SUCCESS) {
+        block(buffer.getLocalAddress(), buffer.getSize());
+    }
+}
+
+
+//
+// Opaque object returned by _dyld_process_info_create()
+//
+
+struct __attribute__((visibility("hidden"))) dyld_process_info_deleter { // deleter
+    //    dyld_process_info_deleter() {};
+    //    dyld_process_info_deleter(const dyld_process_info_deleter&) { }
+    //    dyld_process_info_deleter(dyld_process_info_deleter&) {}
+    //    dyld_process_info_deleter(dyld_process_info_deleter&&) {}
+    void operator()(dyld_process_info_base* p) const {
+        if (p) {
+            free(p);
+        }
+    };
+};
+
+static dyld_process_info_deleter deleter;
+typedef std::unique_ptr<dyld_process_info_base, dyld_process_info_deleter> dyld_process_info_ptr;
+
+struct __attribute__((visibility("hidden"))) dyld_process_info_base {
+    template<typename T1, typename T2>
+    static dyld_process_info_ptr make(task_t task, const T1& allImageInfo, uint64_t timestamp, kern_return_t* kr);
+    template<typename T>
+    static dyld_process_info_ptr makeSuspended(task_t task, const T& allImageInfo, kern_return_t* kr);
+
+    std::atomic<uint32_t>&      retainCount() const { return _retainCount; }
+    dyld_process_cache_info*    cacheInfo() const { return (dyld_process_cache_info*)(((char*)this) + _cacheInfoOffset); }
+    dyld_process_state_info*    stateInfo() const { return (dyld_process_state_info*)(((char*)this) + _stateInfoOffset); }
+    void                        forEachImage(void (^callback)(uint64_t machHeaderAddress, const uuid_t uuid, const char* path)) const;
+    void                        forEachSegment(uint64_t machHeaderAddress, void (^callback)(uint64_t segmentAddress, uint64_t segmentSize, const char* segmentName)) const;
+
+    void retain()
+    {
+        _retainCount++;
+    }
+
+    void release()
+    {
+        uint32_t newCount = --_retainCount;
+
+        if ( newCount == 0 ) {
+            free(this);
+        }
+    }
+
+private:
+    struct ImageInfo {
+        uuid_t                  uuid;
+        uint64_t                loadAddress;
+        const char*             path;
+        uint32_t                segmentStartIndex;
+        uint32_t                segmentsCount;
+    };
+
+    struct SegmentInfo {
+        const char*             name;
+        uint64_t                addr;
+        uint64_t                size;
+    };
+
+                                dyld_process_info_base(unsigned imageCount, size_t totalSize);
+    void*                       operator new (size_t, void* buf) { return buf; }
+
+    static bool                 inCache(uint64_t addr) { return (addr > SHARED_REGION_BASE) && (addr < SHARED_REGION_BASE+SHARED_REGION_SIZE); }
+    kern_return_t               addImage(task_t task, bool sameCacheAsThisProcess, uint64_t imageAddress, uint64_t imagePath, const char* imagePathLocal);
+
+    kern_return_t               addDyldImage(task_t task, uint64_t dyldAddress, uint64_t dyldPathAddress, const char* localPath);
+
+    bool                        invalid() { return ((char*)_stringRevBumpPtr < (char*)_curSegment); }
+    const char*                 copyPath(task_t task, uint64_t pathAddr, kern_return_t* kr);
+    const char*                 addString(const char*, size_t);
+    const char*                 copySegmentName(const char*);
+
+    void                        addInfoFromLoadCommands(const mach_header* mh, uint64_t addressInTask, size_t size);
+    kern_return_t               addInfoFromRemoteLoadCommands(task_t task, uint64_t remoteMH);
+
+    void                        inspectLocalImageLoadCommands(uint64_t imageAddress, void* func);
+    kern_return_t               inspectRemoteImageLoadCommands(task_t task, uint64_t imageAddress, void* func);
+
+    mutable std::atomic<uint32_t>            _retainCount;
+    const uint32_t              _cacheInfoOffset;
+    const uint32_t              _stateInfoOffset;
+    const uint32_t              _imageInfosOffset;
+    const uint32_t              _segmentInfosOffset;
+    ImageInfo* const            _firstImage;
+    ImageInfo*                  _curImage;
+    SegmentInfo* const          _firstSegment;
+    SegmentInfo*                _curSegment;
+    uint32_t                    _curSegmentIndex;
+    char*                       _stringRevBumpPtr;
+
+    // dyld_process_cache_info  cacheInfo;
+    // dyld_process_state_info  stateInfo;
+    // ImageInfo                images[];
+    // SegmentInfo              segments[];
+    // char                     stringPool[]
+};
+
+dyld_process_info_base::dyld_process_info_base(unsigned imageCount, size_t totalSize)
+ :  _retainCount(1), _cacheInfoOffset(sizeof(dyld_process_info_base)),
+    _stateInfoOffset(sizeof(dyld_process_info_base) + sizeof(dyld_process_cache_info)),
+    _imageInfosOffset(sizeof(dyld_process_info_base) + sizeof(dyld_process_cache_info) + sizeof(dyld_process_state_info)),
+    _segmentInfosOffset(sizeof(dyld_process_info_base) + sizeof(dyld_process_cache_info) + sizeof(dyld_process_state_info) + imageCount*sizeof(ImageInfo)),
+    _firstImage((ImageInfo*)(((uint8_t*)this) + _imageInfosOffset)),
+    _curImage((ImageInfo*)(((uint8_t*)this) + _imageInfosOffset)),
+    _firstSegment((SegmentInfo*)(((uint8_t*)this) + _segmentInfosOffset)),
+    _curSegment((SegmentInfo*)(((uint8_t*)this) + _segmentInfosOffset)),
+    _curSegmentIndex(0),
+    _stringRevBumpPtr((char*)(this)+totalSize)
+{
+}
+
+template<typename T1, typename T2>
+dyld_process_info_ptr dyld_process_info_base::make(task_t task, const T1& allImageInfo, uint64_t timestamp, kern_return_t* kr)
+{
+    __block dyld_process_info_ptr result = nullptr;
+
+    // bail out of dyld is too old
+    if ( allImageInfo.version < 15 ) {
+        *kr = KERN_FAILURE;
+        return nullptr;
+    }
+
+    // Check if the process is suspended
+    if (allImageInfo.infoArrayChangeTimestamp == 0) {
+        result = dyld_process_info_base::makeSuspended<T1>(task, allImageInfo, kr);
+        // If we have a result return it, otherwise rescan
+        if (result) {
+            // If it returned the process is suspended and there is nothing more to do
+            return std::move(result);
+        } else {
+            // Check to see if the process change timestamp is greater than 0, if not then sleep to let the process
+            // finish initializing
+            if (allImageInfo.infoArrayChangeTimestamp == 0) {
+                usleep(1000 * 50); // 50ms
+            }
+        }
+    }
+
+    // Test to see if there are no changes and we can exit early
+    if (timestamp != 0 && timestamp == allImageInfo.infoArrayChangeTimestamp) {
+        *kr = KERN_SUCCESS;
+        return nullptr;
+    }
+
+    for(uint32_t i = 0; i < 10; ++i) {
+        uint64_t currentTimestamp = allImageInfo.infoArrayChangeTimestamp;
+        mach_vm_address_t infoArray = allImageInfo.infoArray;
+        if (currentTimestamp == 0) continue;
+        if (infoArray == 0) {
+            // Check if the task is suspended mid dylib load and exit early
+            mach_task_basic_info ti;
+            mach_msg_type_number_t count = MACH_TASK_BASIC_INFO_COUNT;
+            if ((*kr = task_info(task, MACH_TASK_BASIC_INFO, (task_info_t)&ti, &count))) {
+                continue;
+            }
+
+            // The task is suspended, exit
+            if (ti.suspend_count != 0) {
+                // Not exactly correct, but conveys that operation may succeed in the future
+                *kr = KERN_RESOURCE_SHORTAGE;
+                return  nullptr;
+            }
+            continue;
+        };
+
+        // For the moment we are going to truncate any image list longer than 8192 because some programs do
+        // terrible things that corrupt their own image lists and we need to stop clients from crashing
+        // reading them. We can try to do something more advanced in the future. rdar://27446361
+        uint32_t imageCount = allImageInfo.infoArrayCount;
+        imageCount = MIN(imageCount, 8192);
+        size_t imageArraySize = imageCount * sizeof(T2);
+
+        withRemoteBuffer(task, infoArray, imageArraySize, false, false, kr, ^(void *buffer, size_t size) {
+            // figure out how many path strings will need to be copied and their size
+            T2* imageArray = (T2 *)buffer;
+            const dyld_all_image_infos* myInfo = _dyld_get_all_image_infos();
+            bool sameCacheAsThisProcess = !allImageInfo.processDetachedFromSharedRegion
+                && !myInfo->processDetachedFromSharedRegion
+                && ((memcmp(myInfo->sharedCacheUUID, &allImageInfo.sharedCacheUUID[0], 16) == 0)
+                && (myInfo->sharedCacheSlide == allImageInfo.sharedCacheSlide));
+            unsigned countOfPathsNeedingCopying = 0;
+            if ( sameCacheAsThisProcess ) {
+                for (uint32_t i=0; i < imageCount; ++i) {
+                    if ( !inCache(imageArray[i].imageFilePath) )
+                        ++countOfPathsNeedingCopying;
+                }
+            }
+            else {
+                countOfPathsNeedingCopying = imageCount+1;
+            }
+            unsigned imageCountWithDyld = imageCount+1;
+
+            // allocate result object
+            size_t allocationSize = sizeof(dyld_process_info_base)
+                                        + sizeof(dyld_process_cache_info)
+                                        + sizeof(dyld_process_state_info)
+                                        + sizeof(ImageInfo)*(imageCountWithDyld)
+                                        + sizeof(SegmentInfo)*imageCountWithDyld*5
+                                        + countOfPathsNeedingCopying*PATH_MAX;
+            void* storage = malloc(allocationSize);
+            auto info = dyld_process_info_ptr(new (storage) dyld_process_info_base(imageCountWithDyld, allocationSize), deleter);
+            //info =  new (storage) dyld_process_info_base(imageCountWithDyld, allocationSize); // placement new()
+
+            // fill in base info
+            dyld_process_cache_info* cacheInfo = info->cacheInfo();
+            memcpy(cacheInfo->cacheUUID, &allImageInfo.sharedCacheUUID[0], 16);
+            cacheInfo->cacheBaseAddress    = allImageInfo.sharedCacheBaseAddress;
+            cacheInfo->privateCache        = allImageInfo.processDetachedFromSharedRegion;
+            // if no cache is used, allImageInfo has all zeros for cache UUID
+            cacheInfo->noCache = true;
+            for (int i=0; i < 16; ++i) {
+                if ( cacheInfo->cacheUUID[i] != 0 ) {
+                    cacheInfo->noCache = false;
+                }
+            }
+
+            dyld_process_state_info* stateInfo = info->stateInfo();
+            stateInfo->timestamp           = currentTimestamp;
+            stateInfo->imageCount          = imageCountWithDyld;
+            stateInfo->initialImageCount   = (uint32_t)(allImageInfo.initialImageCount+1);
+            stateInfo->dyldState = dyld_process_state_dyld_initialized;
+
+            if ( allImageInfo.libSystemInitialized != 0 ) {
+                stateInfo->dyldState = dyld_process_state_libSystem_initialized;
+                if ( allImageInfo.initialImageCount != imageCount ) {
+                    stateInfo->dyldState = dyld_process_state_program_running;
+                }
+            }
+            if ( allImageInfo.errorMessage != 0 ) {
+                stateInfo->dyldState = allImageInfo.terminationFlags ? dyld_process_state_terminated_before_inits : dyld_process_state_dyld_terminated;
+            }
+            // fill in info for dyld
+            if ( allImageInfo.dyldPath != 0 ) {
+                if ((*kr = info->addDyldImage(task, allImageInfo.dyldImageLoadAddress, allImageInfo.dyldPath, NULL))) {
+                    result = nullptr;
+                    return;
+                }
+            }
+            // fill in info for each image
+            for (uint32_t i=0; i < imageCount; ++i) {
+                if ((*kr = info->addImage(task, sameCacheAsThisProcess, imageArray[i].imageLoadAddress, imageArray[i].imageFilePath, NULL))) {
+                    result = nullptr;
+                    return;
+                }
+            }
+            // sanity check internal data did not overflow
+            if ( info->invalid() ) {
+                *kr = KERN_FAILURE;
+                result = nullptr;
+                return;
+            }
+
+            result = std::move(info);
+        });
+
+        if (result) break;
+    }
+
+    return std::move(result);
+}
+
+template<typename T>
+dyld_process_info_ptr dyld_process_info_base::makeSuspended(task_t task, const T& allImageInfo, kern_return_t* kr)
+{
+    pid_t   pid;
+    if ((*kr = pid_for_task(task, &pid))) {
+        return NULL;
+    }
+
+    mach_task_basic_info ti;
+    mach_msg_type_number_t count = MACH_TASK_BASIC_INFO_COUNT;
+    if ((*kr = task_info(task, MACH_TASK_BASIC_INFO, (task_info_t)&ti, &count))) {
+        return  nullptr;
+    }
+
+    // The task is not suspended, exit
+    if (ti.suspend_count == 0) {
+        return  nullptr;
+    }
+
+    __block unsigned    imageCount = 0;  // main executable and dyld
+    __block uint64_t    mainExecutableAddress = 0;
+    __block uint64_t    dyldAddress = 0;
+    char                dyldPathBuffer[PATH_MAX+1];
+    char                mainExecutablePathBuffer[PATH_MAX+1];
+    __block char *      dyldPath = &dyldPathBuffer[0];
+    __block char *      mainExecutablePath = &mainExecutablePathBuffer[0];
+    mach_vm_size_t      size;
+    for (mach_vm_address_t address = 0; ; address += size) {
+        vm_region_basic_info_data_64_t  info;
+        mach_port_t                     objectName;
+        unsigned int                    infoCount = VM_REGION_BASIC_INFO_COUNT_64;
+        if (kern_return_t r = mach_vm_region(task, &address, &size, VM_REGION_BASIC_INFO,
+                                             (vm_region_info_t)&info, &infoCount, &objectName)) {
+            break;
+        }
+        if ( info.protection != (VM_PROT_READ|VM_PROT_EXECUTE) )
+            continue;
+            // read start of vm region to verify it is a mach header
+            withRemoteObject(task, address, false, NULL, ^(mach_header_64 mhBuffer){
+                if ( (mhBuffer.magic != MH_MAGIC) && (mhBuffer.magic != MH_MAGIC_64) )
+                    return;
+                // now know the region is the start of a mach-o file
+                if ( mhBuffer.filetype == MH_EXECUTE ) {
+                    mainExecutableAddress = address;
+                    int len = proc_regionfilename(pid, mainExecutableAddress, mainExecutablePath, PATH_MAX);
+                    if ( len != 0 ) {
+                        mainExecutablePath[len] = '\0';
+                    }
+                    ++imageCount;
+                }
+                else if ( mhBuffer.filetype == MH_DYLINKER ) {
+                    dyldAddress = address;
+                    int len = proc_regionfilename(pid, dyldAddress, dyldPath, PATH_MAX);
+                    if ( len != 0 ) {
+                        dyldPath[len] = '\0';
+                    }
+                    ++imageCount;
+                }
+            });
+            //fprintf(stderr, "vm region: addr=0x%llX, size=0x%llX, prot=0x%X\n", (uint64_t)address, (uint64_t)size, info.protection);
+    }
+    //fprintf(stderr, "dyld: addr=0x%llX, path=%s\n", dyldAddress, dyldPathBuffer);
+    //fprintf(stderr, "app:  addr=0x%llX, path=%s\n", mainExecutableAddress, mainExecutablePathBuffer);
+
+    // allocate result object
+    size_t allocationSize =   sizeof(dyld_process_info_base)
+                            + sizeof(dyld_process_cache_info)
+                            + sizeof(dyld_process_state_info)
+                            + sizeof(ImageInfo)*(imageCount)
+                            + sizeof(SegmentInfo)*imageCount*5
+                            + imageCount*PATH_MAX;
+    void* storage = malloc(allocationSize);
+    auto obj = dyld_process_info_ptr(new (storage) dyld_process_info_base(imageCount, allocationSize), deleter);
+    // fill in base info
+    dyld_process_cache_info* cacheInfo = obj->cacheInfo();
+    bzero(cacheInfo->cacheUUID, 16);
+    cacheInfo->cacheBaseAddress    = 0;
+    cacheInfo->noCache             = true;
+    cacheInfo->privateCache        = false;
+
+    dyld_process_state_info* stateInfo = obj->stateInfo();
+    stateInfo->timestamp           = 0;
+    stateInfo->imageCount          = imageCount;
+    stateInfo->initialImageCount   = imageCount;
+    stateInfo->dyldState           = dyld_process_state_not_started;
+
+    // fill in info for dyld
+    if ( dyldAddress != 0 ) {
+        if ((*kr = obj->addDyldImage(task, dyldAddress, 0, dyldPath))) {
+            return nullptr;
+        }
+    }
+
+    // fill in info for each image
+    if ( mainExecutableAddress != 0 ) {
+        if ((*kr = obj->addImage(task, false, mainExecutableAddress, 0, mainExecutablePath))) {
+            return nullptr;
+        }
+    }
+
+    if (allImageInfo.infoArrayChangeTimestamp != 0) {
+        return  nullptr;
+    }
+
+    count = MACH_TASK_BASIC_INFO_COUNT;
+    if ((*kr = task_info(task, MACH_TASK_BASIC_INFO, (task_info_t)&ti, &count))) {
+        return  nullptr;
+    }
+
+    // The task is not suspended, exit
+    if (ti.suspend_count == 0) {
+        return  nullptr;
+    }
+
+    return obj;
+}
+
+
+
+const char* dyld_process_info_base::addString(const char* str, size_t maxlen)
+{
+    size_t len = strnlen(str, maxlen) + 1;
+    _stringRevBumpPtr -= len;
+    strlcpy(_stringRevBumpPtr, str, len);
+    return _stringRevBumpPtr;
+}
+
+const char* dyld_process_info_base::copyPath(task_t task, uint64_t stringAddressInTask, kern_return_t* kr)
+{
+    __block const char* retval = NULL;
+    withRemoteBuffer(task, stringAddressInTask, PATH_MAX, false, true, kr, ^(void *buffer, size_t size) {
+        retval = addString(static_cast<const char *>(buffer), size);
+    });
+    return retval;
+}
+
+kern_return_t dyld_process_info_base::addImage(task_t task, bool sameCacheAsThisProcess, uint64_t imageAddress, uint64_t imagePath, const char* imagePathLocal)
+{
+    kern_return_t kr = KERN_SUCCESS;
+    _curImage->loadAddress = imageAddress;
+    _curImage->segmentStartIndex = _curSegmentIndex;
+    if ( imagePathLocal != NULL ) {
+        _curImage->path = addString(imagePathLocal, PATH_MAX);
+    }
+    else if ( sameCacheAsThisProcess && inCache(imagePath) ) {
+        _curImage->path = (const char*)imagePath;
+    }
+    else {
+        _curImage->path = copyPath(task, imagePath, &kr);
+        if ( kr != KERN_SUCCESS)
+            return kr;
+    }
+    if ( sameCacheAsThisProcess && inCache(imageAddress) ) {
+        addInfoFromLoadCommands((mach_header*)imageAddress, imageAddress, 32*1024);
+    }
+    else {
+        kr = addInfoFromRemoteLoadCommands(task, imageAddress);
+        if ( kr != KERN_SUCCESS)
+            return kr;
+    }
+    _curImage->segmentsCount = _curSegmentIndex - _curImage->segmentStartIndex;
+    _curImage++;
+    return KERN_SUCCESS;
+}
+
+
+kern_return_t dyld_process_info_base::addInfoFromRemoteLoadCommands(task_t task, uint64_t remoteMH) {
+    __block kern_return_t kr = KERN_SUCCESS;
+    __block size_t headerPagesSize = 0;
+    __block bool done = false;
+
+    //Since the minimum we can reasonably map is a page, map that.
+    withRemoteBuffer(task, remoteMH, PAGE_SIZE, false, false, &kr, ^(void * buffer, size_t size) {
+        const mach_header* mh = (const mach_header*)buffer;
+        headerPagesSize = sizeof(mach_header) + mh->sizeofcmds;
+        if (headerPagesSize <= PAGE_SIZE) {
+            addInfoFromLoadCommands(mh, remoteMH, size);
+            done = true;
+        }
+    });
+
+    //The load commands did not fit in the first page, but now we know the size, so remap and try again
+    if (!done) {
+        if (kr != KERN_SUCCESS) {
+            return kr;
+        }
+        withRemoteBuffer(task, remoteMH, headerPagesSize, false, false, &kr, ^(void * buffer, size_t size) {
+            addInfoFromLoadCommands((mach_header*)buffer, remoteMH, size);
+        });
+    }
+
+    return kr;
+}
+
+kern_return_t dyld_process_info_base::addDyldImage(task_t task, uint64_t dyldAddress, uint64_t dyldPathAddress, const char* localPath)
+{
+    __block kern_return_t kr = KERN_SUCCESS;
+    _curImage->loadAddress = dyldAddress;
+    _curImage->segmentStartIndex = _curSegmentIndex;
+    if ( localPath != NULL ) {
+        _curImage->path = addString(localPath, PATH_MAX);
+    }
+    else {
+        _curImage->path = copyPath(task, dyldPathAddress, &kr);
+        if ( kr != KERN_SUCCESS)
+            return kr;
+    }
+
+    kr = addInfoFromRemoteLoadCommands(task, dyldAddress);
+    if ( kr != KERN_SUCCESS)
+        return kr;
+
+    _curImage->segmentsCount = _curSegmentIndex - _curImage->segmentStartIndex;
+    _curImage++;
+    return KERN_SUCCESS;
+}
+
+
+void dyld_process_info_base::addInfoFromLoadCommands(const mach_header* mh, uint64_t addressInTask, size_t size)
+{
+    const load_command* startCmds = NULL;
+    if ( mh->magic == MH_MAGIC_64 )
+        startCmds = (load_command*)((char *)mh + sizeof(mach_header_64));
+    else if ( mh->magic == MH_MAGIC )
+        startCmds = (load_command*)((char *)mh + sizeof(mach_header));
+    else
+        return;  // not a mach-o file, or wrong endianness
+
+    const load_command* const cmdsEnd = (load_command*)((char*)startCmds + mh->sizeofcmds);
+    const load_command* cmd = startCmds;
+    for(uint32_t i = 0; i < mh->ncmds; ++i) {
+        const load_command* nextCmd = (load_command*)((char *)cmd + cmd->cmdsize);
+        if ( (cmd->cmdsize < 8) || (nextCmd > cmdsEnd) || (nextCmd < startCmds) ) {
+            return;  // malformed load command
+        }
+        if ( cmd->cmd == LC_UUID ) {
+            const uuid_command* uuidCmd = (uuid_command*)cmd;
+            memcpy(_curImage->uuid, uuidCmd->uuid, 16);
+        }
+        else if ( cmd->cmd == LC_SEGMENT ) {
+            const segment_command* segCmd = (segment_command*)cmd;
+            _curSegment->name = copySegmentName(segCmd->segname);
+            _curSegment->addr = segCmd->vmaddr;
+            _curSegment->size = segCmd->vmsize;
+            _curSegment++;
+            _curSegmentIndex++;
+        }
+        else if ( cmd->cmd == LC_SEGMENT_64 ) {
+            const segment_command_64* segCmd = (segment_command_64*)cmd;
+            _curSegment->name = copySegmentName(segCmd->segname);
+            _curSegment->addr = segCmd->vmaddr;
+            _curSegment->size = segCmd->vmsize;
+            _curSegment++;
+            _curSegmentIndex++;
+        }
+        cmd = nextCmd;
+    }
+}
+
+const char* dyld_process_info_base::copySegmentName(const char* name)
+{
+    // don't copy names of standard segments into string pool
+    static const char* stdSegNames[] = {"__TEXT", "__DATA", "__LINKEDIT", "__DATA_DIRTY", "__DATA_CONST", "__OBJC", NULL };
+    for (const char** s=stdSegNames; *s != NULL; ++s) {
+        if ( strcmp(name, *s) == 0 )
+        return *s;
+    }
+    // copy custom segment names into string pool
+    return addString(name, 16);
+}
+
+void dyld_process_info_base::forEachImage(void (^callback)(uint64_t machHeaderAddress, const uuid_t uuid, const char* path)) const
+{
+    for (const ImageInfo* p = _firstImage; p < _curImage; ++p) {
+        callback(p->loadAddress, p->uuid, p->path);
+    }
+}
+
+void dyld_process_info_base::forEachSegment(uint64_t machHeaderAddress, void (^callback)(uint64_t segmentAddress, uint64_t segmentSize, const char* segmentName)) const
+{
+    for (const ImageInfo* p = _firstImage; p < _curImage; ++p) {
+        if ( p->loadAddress == machHeaderAddress ) {
+            uint64_t slide = 0;
+            for (uint32_t i=0; i < p->segmentsCount; ++i) {
+                const SegmentInfo* seg = &_firstSegment[p->segmentStartIndex+i];
+                if ( strcmp(seg->name, "__TEXT") == 0 ) {
+                    slide = machHeaderAddress - seg->addr;
+                    break;
+                }
+            }
+            for (uint32_t i=0; i < p->segmentsCount; ++i) {
+                const SegmentInfo* seg = &_firstSegment[p->segmentStartIndex+i];
+                callback(seg->addr + slide, seg->size, seg->name);
+            }
+            break;
+        }
+    }
+}
+
+dyld_process_info _dyld_process_info_create(task_t task, uint64_t timestamp, kern_return_t* kr)
+{
+    __block dyld_process_info result = nullptr;
+    kern_return_t krSink = KERN_SUCCESS;
+    if (kr == nullptr) {
+        kr = &krSink;
+    }
+    *kr = KERN_SUCCESS;
+
+    task_dyld_info_data_t task_dyld_info;
+    mach_msg_type_number_t count = TASK_DYLD_INFO_COUNT;
+    if ( kern_return_t r = task_info(task, TASK_DYLD_INFO, (task_info_t)&task_dyld_info, &count) ) {
+        *kr = r;
+        return  nullptr;
+    }
+
+    //The kernel will return MACH_VM_MIN_ADDRESS for an executable that has not had dyld loaded
+    if (task_dyld_info.all_image_info_addr == MACH_VM_MIN_ADDRESS)
+        return nullptr;
+
+    if ( task_dyld_info.all_image_info_size > sizeof(dyld_all_image_infos_64) )
+        return nullptr;
+
+    // We use a true shared memory buffer here, that way by making sure that libdyld in both processes
+    // reads and writes the the timestamp atomically we can make sure we get a coherent view of the
+    // remote process.
+    // That also means that we *MUST* directly read the memory, which is why we template the make() call
+    withRemoteBuffer(task, task_dyld_info.all_image_info_addr, task_dyld_info.all_image_info_size, true, false, kr, ^(void *buffer, size_t size) {
+        dyld_process_info_ptr base;
+        if (task_dyld_info.all_image_info_format == TASK_DYLD_ALL_IMAGE_INFO_32 ) {
+            const dyld_all_image_infos_32* info = (const dyld_all_image_infos_32*)buffer;
+            base = dyld_process_info_base::make<dyld_all_image_infos_32, dyld_image_info_32>(task, *info, timestamp, kr);
+        } else {
+            const dyld_all_image_infos_64* info = (const dyld_all_image_infos_64*)buffer;
+            base = dyld_process_info_base::make<dyld_all_image_infos_64, dyld_image_info_64>(task, *info, timestamp, kr);
+        }
+        if (base) {
+            result = base.release();
+        }
+    });
+    return  result;
+}
+
+void _dyld_process_info_get_state(dyld_process_info info, dyld_process_state_info* stateInfo)
+{
+    *stateInfo = *info->stateInfo();
+}
+
+void _dyld_process_info_get_cache(dyld_process_info info, dyld_process_cache_info* cacheInfo)
+{
+    *cacheInfo = *info->cacheInfo();
+}
+
+void _dyld_process_info_retain(dyld_process_info object)
+{
+    const_cast<dyld_process_info_base*>(object)->retain();
+}
+
+void _dyld_process_info_release(dyld_process_info object)
+{
+    const_cast<dyld_process_info_base*>(object)->release();
+}
+
+void _dyld_process_info_for_each_image(dyld_process_info info, void (^callback)(uint64_t machHeaderAddress, const uuid_t uuid, const char* path))
+{
+    info->forEachImage(callback);
+}
+
+
+void _dyld_process_info_for_each_segment(dyld_process_info info, uint64_t machHeaderAddress, void (^callback)(uint64_t segmentAddress, uint64_t segmentSize, const char* segmentName))
+{
+    info->forEachSegment(machHeaderAddress, callback);
+}
+
+
+