--- /dev/null
+++ dyld/dyld-421.2/interlinked-dylibs/FileCache.cpp
@@ -0,0 +1,234 @@
+/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
+ *
+ * Copyright (c) 2014 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 "mega-dylib-utils.h"
+#include "MachOFileAbstraction.hpp"
+#include "Trie.hpp"
+
+#include <dirent.h>
+#include <sys/errno.h>
+#include <sys/fcntl.h>
+#include <sys/param.h>
+#include <mach-o/loader.h>
+#include <mach-o/fat.h>
+#include <mach-o/dyld.h>
+#include <assert.h>
+#include <Availability.h>
+
+#include <fstream>
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <algorithm>
+#include <unordered_map>
+#include <unordered_set>
+
+#include <System/sys/csr.h>
+
+#include "dyld_cache_config.h"
+
+#include "OptimizerBranches.h"
+
+#include "CacheFileAbstraction.hpp"
+
+#include "mega-dylib-utils.h"
+#include "Logging.h"
+
+
+//#include <rootless.h>
+extern "C" int rootless_check_trusted(const char *path);
+extern "C" int rootless_check_trusted_fd(int fd) __attribute__((weak_import));
+
+static bool            rootlessEnabled;
+static dispatch_once_t onceToken;
+
+bool isProtectedBySIP(const std::string& path, int fd)
+{
+    bool isProtected = false;
+    // Check to make sure file system protections are on at all
+    dispatch_once(&onceToken, ^{
+        rootlessEnabled = csr_check(CSR_ALLOW_UNRESTRICTED_FS);
+    });
+    if (!rootlessEnabled)
+        return false;
+#if __MAC_OS_X_VERSION_MIN_REQUIRED >= 101200
+    if ( (fd != -1) && (&rootless_check_trusted_fd != NULL) )
+        isProtected = (rootless_check_trusted_fd(fd) == 0);
+    else
+#endif
+    if ( &rootless_check_trusted != NULL )
+        isProtected = (rootless_check_trusted(path.c_str()) == 0);
+    return isProtected;
+}
+
+
+std::string toolDir()
+{
+    char buffer[PATH_MAX];
+    uint32_t bufsize = PATH_MAX;
+    int result = _NSGetExecutablePath(buffer, &bufsize);
+    if ( result == 0 ) {
+        std::string path = buffer;
+        size_t pos = path.rfind('/');
+        if ( pos != std::string::npos )
+            return path.substr(0,pos+1);
+    }
+    warning("tool directory not found");
+    return "/tmp/";
+}
+
+std::string baspath(const std::string& path)
+{
+    std::string::size_type slash_pos = path.rfind("/");
+    if (slash_pos != std::string::npos) {
+        slash_pos++;
+        return path.substr(slash_pos);
+    } else {
+        return path;
+    }
+}
+
+std::string dirpath(const std::string& path)
+{
+    std::string::size_type slash_pos = path.rfind("/");
+    if (slash_pos != std::string::npos) {
+        slash_pos++;
+        return path.substr(0, slash_pos);
+    } else {
+        char cwd[MAXPATHLEN];
+        (void)getcwd(cwd, MAXPATHLEN);
+        return cwd;
+    }
+}
+
+std::string normalize_absolute_file_path(const std::string &path) {
+    std::vector<std::string> components;
+    std::vector<std::string> processed_components;
+    std::stringstream ss(path);
+    std::string retval;
+    std::string item;
+
+    while (std::getline(ss, item, '/')) {
+        components.push_back(item);
+    }
+
+    if (components[0] == ".") {
+        retval = ".";
+    }
+
+    for (auto& component : components) {
+        if (component.empty() || component == ".")
+            continue;
+        else if (component == ".." && processed_components.size())
+            processed_components.pop_back();
+        else
+            processed_components.push_back(component);
+    }
+
+    for (auto & component : processed_components) {
+        retval = retval + "/" + component;
+    }
+
+    return retval;
+}
+
+FileCache fileCache;
+
+FileCache::FileCache(void) {
+    cache_queue = dispatch_queue_create("com.apple.dyld.cache.cache", DISPATCH_QUEUE_SERIAL);
+}
+
+
+void FileCache::preflightCache(const std::unordered_set<std::string>& paths) {
+    for (auto &path : paths) {
+        preflightCache(path);
+    }
+}
+
+void FileCache::preflightCache(const std::string& path)
+{
+    cacheBuilderDispatchAsync(cache_queue, [=] {
+        std::string normalizedPath = normalize_absolute_file_path(path);
+        if (entries.count(normalizedPath) == 0) {
+            fill(normalizedPath);
+        }
+    });
+}
+
+std::tuple<uint8_t *, struct stat, bool> FileCache::cacheLoad(const std::string path) {
+    std::string normalizedPath = normalize_absolute_file_path(path);
+    cacheBuilderDispatchSync(cache_queue, [=] {
+        if ( entries.count(normalizedPath) == 0 )
+            fill(normalizedPath);
+    });
+
+    return entries[normalizedPath];
+}
+
+
+//FIXME error handling
+void FileCache::fill(const std::string& path) {
+    struct stat stat_buf;
+
+    int fd = ::open(path.c_str(), O_RDONLY, 0);
+    if ( fd == -1 ) {
+        verboseLog("can't open file '%s', errno=%d", path.c_str(), errno);
+        entries[path] = std::make_tuple((uint8_t*)(-1), stat_buf, false);
+        return;
+    }
+
+    if ( fstat(fd, &stat_buf) == -1) {
+        verboseLog("can't stat open file '%s', errno=%d", path.c_str(), errno);
+        entries[path] = std::make_tuple((uint8_t*)(-1), stat_buf, false);
+        ::close(fd);
+        return;
+    }
+
+    if ( stat_buf.st_size < 4096 ) {
+        verboseLog("file too small '%s'", path.c_str());
+        entries[path] = std::make_tuple((uint8_t*)(-1), stat_buf, false);
+        ::close(fd);
+        return;
+    }
+
+    bool rootlessProtected = isProtectedBySIP(path, fd);
+
+    void* buffer_ptr = mmap(NULL, stat_buf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+    if (buffer_ptr == MAP_FAILED) {
+        verboseLog("mmap() for shared cache at %s failed, errno=%d", path.c_str(), errno);
+        entries[path] = std::make_tuple((uint8_t*)(-1), stat_buf, false);
+        ::close(fd);
+        return;
+    }
+
+    entries[path] = std::make_tuple((uint8_t*)buffer_ptr, stat_buf, rootlessProtected);
+    ::close(fd);
+}
+
+
+
+
+
+