-/*
- * Copyright (c) 2000-2004 Apple Computer, 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@
- */
-
-
-//
-// Utilities
-//
-#include <security_utilities/utilities.h>
-#include <CoreFoundation/CoreFoundation.h>
-#include <dispatch/dispatch.h>
-
-namespace Security
-{
-
-static CFMutableDictionaryRef gCacheDictionaryRef = NULL;
-static dispatch_once_t gDictionaryCreated = 0;
-static dispatch_queue_t gSerializeQueue;
-
-char *cached_realpath(const char * file_name, char * resolved_name)
-{
- dispatch_once(&gDictionaryCreated,
- ^{
- gCacheDictionaryRef = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
- gSerializeQueue = dispatch_queue_create("com.apple.SecurityLookupCacheQueue", DISPATCH_QUEUE_SERIAL);
- });
-
-
- __block char* valueToReturn = NULL;
-
- dispatch_sync(gSerializeQueue,
- ^{
- // Put a maximum limit on the size of this cache.
- CFIndex entryCount = CFDictionaryGetCount(gCacheDictionaryRef);
-
- // make the incoming name a string
- CFStringRef input = CFStringCreateWithCString(NULL, file_name, kCFStringEncodingUTF8);
- if (entryCount < OPEN_MAX && input != NULL) // is it acceptable to use the cache?
- {
- // see if we can find that string in our dictionary
- CFStringRef output = (CFStringRef) CFDictionaryGetValue(gCacheDictionaryRef, input);
-
- if (output == NULL)
- {
- // the string is not in our cache, so use realpath
- valueToReturn = realpath(file_name, resolved_name);
- if (valueToReturn != NULL) // no error, so continue
- {
- // make a new entry in the dictionary for our string
- output = CFStringCreateWithCString(NULL, valueToReturn, kCFStringEncodingUTF8);
- CFDictionaryAddValue(gCacheDictionaryRef, input, output);
- CFRelease(output);
- }
- }
- else
- {
- char* valueToFree = NULL;
-
- // we need to extract the value from the output
-
- // figure out how big to make our buffer
- CFIndex size = CFStringGetMaximumSizeForEncoding(CFStringGetLength(output), kCFStringEncodingUTF8) + 1; // account for NULL termination
-
- // if the user has passed in a buffer, use it. If not, allocate our own
-
- // technically, we don't know the size of the buffer that the
- // user has passed in. It has to be large enough to hold the
- // string, however, so we can use size as an estimator. The
- // result will be the same, however: If the user didn't supply
- // enough memory, he will crash. We behave exactly the same
- // as realpath, which is the idea.
- char *buffer = resolved_name;
-
- // allocate a buffer if none was passed in
- if (buffer == NULL) {
- valueToFree = buffer = (char*) malloc(size);
- }
-
- if (buffer != NULL) // check to see if malloc failed earlier
- {
- if (!CFStringGetCString(output, buffer, size, kCFStringEncodingUTF8))
- {
- free((void*) valueToFree);
- valueToReturn = NULL;
- }
- else
- {
- valueToReturn = buffer;
- }
- }
- }
- }
- else
- {
- valueToReturn = realpath(file_name, resolved_name);
- }
-
- CFRelease(input);
- });
-
- return valueToReturn;
-}
-
-}
-
-