1/* 2 * Copyright (c) 2013 Apple, Inc. All rights reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. Please obtain a copy of the License at 10 * http://www.opensource.apple.com/apsl/ and read it before using this 11 * file. 12 * 13 * The Original Code and all software distributed under the License are 14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 18 * Please see the License for the specific language governing rights and 19 * limitations under the License. 20 * 21 * @APPLE_LICENSE_HEADER_END@ 22 */ 23 24#ifndef _XATTR_FLAGS_H 25#define _XATTR_FLAGS_H 26 27#include <stdint.h> 28 29#include <sys/cdefs.h> 30#include <Availability.h> 31 32__BEGIN_DECLS 33 34/* 35 * xattr_operation_intent_t is used to declare what the intent of the copy is. 36 * Not a bit-field (for now, at least). 37 * 38 * XATTR_OPERATION_INTENT_COPY indicates that the EA is attached to an object 39 * that is simply being copied. E.g., cp src dst 40 * 41 * XATTR_OPERATION_INTENT_SAVE indicates that the EA is attached to an object 42 * being saved; as in a "safe save," the destination is being replaced by 43 * the source, so the question is whether the EA should be applied to the 44 * destination, or generated anew. 45 * 46 * XATTR_OPERATION_INTENT_SHARE indicates that the EA is attached to an object that 47 * is being given out to other people. For example, saving to a public folder, 48 * or attaching to an email message. 49 * 50 * XATTR_OPERATION_INTENT_SYNC indicates that the EA is attached to an object that 51 * is being synced to other storages for the same user. For example synced to 52 * iCloud. 53 */ 54 55#define XATTR_OPERATION_INTENT_COPY 1 56#define XATTR_OPERATION_INTENT_SAVE 2 57#define XATTR_OPERATION_INTENT_SHARE 3 58#define XATTR_OPERATION_INTENT_SYNC 4 59 60typedef unsigned int xattr_operation_intent_t; 61 62typedef uint64_t xattr_flags_t; 63 64/* 65 * Various properties used to determine how to handle the xattr during 66 * copying. The intent is that the default is reasonable for most xattrs. 67 */ 68 69/* 70 * XATTR_FLAG_NO_EXPORT 71 * Declare that the extended property should not be exported; this is 72 * deliberately a bit vague, but this is used by XATTR_OPERATION_INTENT_SHARE 73 * to indicate not to preserve the xattr. 74 */ 75#define XATTR_FLAG_NO_EXPORT ((xattr_flags_t)0x0001) 76 77/* 78 * XATTR_FLAG_CONTENT_DEPENDENT 79 * Declares the extended attribute to be tied to the contents of the file (or 80 * vice versa), such that it should be re-created when the contents of the 81 * file change. Examples might include cryptographic keys, checksums, saved 82 * position or search information, and text encoding. 83 * 84 * This property causes the EA to be preserved for copy and share, but not for 85 * safe save. (In a safe save, the EA exists on the original, and will not 86 * be copied to the new version.) 87 */ 88#define XATTR_FLAG_CONTENT_DEPENDENT ((xattr_flags_t)0x0002) 89 90/* 91 * XATTR_FLAG_NEVER_PRESERVE 92 * Declares that the extended attribute is never to be copied, for any 93 * intention type. 94 */ 95#define XATTR_FLAG_NEVER_PRESERVE ((xattr_flags_t)0x0004) 96 97/* 98 * XATTR_FLAG_SYNCABLE 99 * Declares that the extended attribute is to be synced, used by the 100 * XATTR_OPERATION_ITENT_SYNC intention. Syncing tends to want to minimize the 101 * amount of metadata synced around, hence the default behavior is for the EA 102 * NOT to be synced, even if it would else be preserved for the 103 * XATTR_OPERATION_ITENT_COPY intention. 104 */ 105#define XATTR_FLAG_SYNCABLE ((xattr_flags_t)0x0008) 106 107/* Given a named extended attribute, and a copy intent, should the EA be preserved? */ 108extern int xattr_preserve_for_intent(const char *, xattr_operation_intent_t) __OSX_AVAILABLE_STARTING( __MAC_10_10, __IPHONE_8_0); 109 110/* 111 * Given an extended attribute name, and a set of properties, return an 112 * allocated C string with the name. This will return NULL on error; 113 * errno may be set to ENOMEM if the new name cannot be allocated, or 114 * ENAMETOOLONG if the new name is longer than the maximum for EAs (127 UTF8 115 * characters). The caller must deallocate the return value otherwise. 116 * 117 * If no properties are set, it returns a copy of the EA name. 118 * 119 * If the EA name is in the internal list, and the properties are the same as 120 * defined there, then it will also return an unmodified copy of the EA name. 121 */ 122extern char *xattr_name_with_flags(const char *, xattr_flags_t) __OSX_AVAILABLE_STARTING( __MAC_10_10, __IPHONE_8_0); 123 124/* 125 * Given an extended attribute name, which may or may not have properties encoded 126 * as a suffix, return just the name of the attribute. E.g., com.example.mine#P 127 * would return "com.example.mine". The return value will be NULL on error; 128 * errno will be set to ENOMEM if it cannot be allocated. The caller must deallocate 129 * the return value. 130 */ 131extern char *xattr_name_without_flags(const char *) __OSX_AVAILABLE_STARTING( __MAC_10_10, __IPHONE_8_0); 132 133/* 134 * Given an EA name, return the properties. If the name is in the internal list, 135 * those properties will be returned. Unknown property encodings are ignored. 136 */ 137extern xattr_flags_t xattr_flags_from_name(const char *) __OSX_AVAILABLE_STARTING( __MAC_10_10, __IPHONE_8_0); 138 139/* 140 * Given an xattr_operation_intent_t and an xattr_flags_t, return whether it should 141 * be preserved. The default (in case either flags or intent is 0, or unknown 142 * values) is to return 1; it only returns 0 if the flags and intent indicate it 143 * should not be preserved. 144 */ 145extern int xattr_intent_with_flags(xattr_operation_intent_t, xattr_flags_t) __OSX_AVAILABLE_STARTING( __MAC_10_10, __IPHONE_8_0); 146 147__END_DECLS 148 149#endif /* _XATTR_FLAGS_H */ 150