
ARCHIVE_ENTRY_ACL(3)	 BSD Library Functions Manual	  ARCHIVE_ENTRY_ACL(3)

NAME
     archive_entry_acl_add_entry, archive_entry_acl_add_entry_w,
     archive_entry_acl_clear, archive_entry_acl_count, archive_entry_acl_next,
     archive_entry_acl_next_w, archive_entry_acl_reset,
     archive_entry_acl_text_w — functions for manipulating Access Control
     Lists in archive entry descriptions

SYNOPSIS
     #include <archive_entry.h>

     void
     archive_entry_acl_add_entry(struct archive_entry *a, int type,
	 int permset, int tag, int qualifier, const char *name);

     void
     archive_entry_acl_add_entry_w(struct archive_entry *a, int type,
	 int permset, int tag, int qualifier, const wchar_t *name);

     void
     archive_entry_acl_clear(struct archive_entry *a);

     int
     archive_entry_acl_count(struct archive_entry *a, int type);

     int
     archive_entry_acl_next(struct archive_entry *a, int type, int *ret_type,
	 int *ret_permset, int *ret_tag, int *ret_qual,
	 const char **ret_name);

     int
     archive_entry_acl_next_w(struct archive_entry *a, int type,
	 int *ret_type, int *ret_permset, int *ret_tag, int *ret_qual,
	 const wchar_t **ret_name);

     int
     archive_entry_acl_reset(struct archive_entry *a, int type);

     const wchar_t *
     archive_entry_acl_text_w(struct archive_entry *a, int flags);

DESCRIPTION
     An “Access Control List” is a generalisation of the classic Unix permis‐
     sion system.  The ACL interface of libarchive is derived from the
     POSIX.1e draft, but restricted to simplify dealing with practical imple‐
     mentations in various Operating Systems and archive formats.

     An ACL consists of a number of independent entries.  Each entry specifies
     the permission set as bitmask of basic permissions.  Valid permissions
     are:
	   ARCHIVE_ENTRY_ACL_EXECUTE
	   ARCHIVE_ENTRY_ACL_WRITE
	   ARCHIVE_ENTRY_ACL_READ
     The permissions correspond to the normal Unix permissions.

     The tag specifies the principal to which the permission applies.  Valid
     values are:
	   ARCHIVE_ENTRY_ACL_USER	The user specified by the name field.
	   ARCHIVE_ENTRY_ACL_USER_OBJ	The owner of the file.
	   ARCHIVE_ENTRY_ACL_GROUP	The group specied by the name field.
	   ARCHIVE_ENTRY_ACL_GROUP_OBJ	The group who owns the file.
	   ARCHIVE_ENTRY_ACL_MASK	The maximum permissions to be obtained
					via group permissions.
	   ARCHIVE_ENTRY_ACL_OTHER	Any principal who doesn’t have a user
					or group entry.
     The principals ARCHIVE_ENTRY_ACL_USER_OBJ, ARCHIVE_ENTRY_ACL_GROUP_OBJ
     and ARCHIVE_ENTRY_ACL_OTHER are equivalent to user, group and other in
     the classic Unix permission model and specify non‐extended ACL entries.

     All files have an access ACL (ARCHIVE_ENTRY_ACL_TYPE_ACCESS).  This spec‐
     ifies the permissions required for access to the file itself.  Directo‐
     ries have an additional ACL (ARCHIVE_ENTRY_ACL_TYPE_DEFAULT), which con‐
     trols the initial access ACL for newly created directory entries.

     archive_entry_acl_add_entry() and archive_entry_acl_add_entry_w() add a
     single ACL entry.	For the access ACL and non‐extended principals, the
     classic Unix permissions are updated.

     archive_entry_acl_clear() removes all ACL entries and resets the enumera‐
     tion pointer.

     archive_entry_acl_count() counts the ACL entries that have the given type
     mask.  type can be the bitwise‐or of ARCHIVE_ENTRY_ACL_TYPE_ACCESS and
     ARCHIVE_ENTRY_ACL_TYPE_DEFAULT.  If ARCHIVE_ENTRY_ACL_TYPE_ACCESS is
     included and at least one extended ACL entry is found, the three non‐
     extened ACLs are added.

     archive_entry_acl_next() and archive_entry_acl_next_w() return the next
     entry of the ACL list.  This functions may only be called after
     archive_entry_acl_reset() has indicated the presence of extended ACL
     entries.

     archive_entry_acl_reset() prepare reading the list of ACL entries with
     archive_entry_acl_next() or archive_entry_acl_next_w().  The function
     returns either 0, if no non‐extended ACLs are found.  In this case, the
     access permissions should be obtained by archive_entry_mode(3) or set
     using chmod(2).  Otherwise, the function returns the same value as
     archive_entry_acl_count().

     archive_entry_acl_text_w() converts the ACL entries for the given type
     mask into a wide string.  In addition to the normal type flags,
     ARCHIVE_ENTRY_ACL_STYLE_EXTRA_ID and ARCHIVE_ENTRY_ACL_STYLE_MARK_DEFAULT
     can be specified to further customize the result.	The returned long
     string is valid until the next call to archive_entry_acl_clear(),
     archive_entry_acl_add_entry(), archive_entry_acl_add_entry_w() or
     archive_entry_acl_text_w().

RETURN VALUES
     archive_entry_acl_count() and archive_entry_acl_reset() returns the num‐
     ber of ACL entries that match the given type mask.  If the type mask
     includes ARCHIVE_ENTRY_ACL_TYPE_ACCESS and at least one extended ACL
     entry exists, the three classic Unix permissions are counted.

     archive_entry_acl_next() and archive_entry_acl_next_w() return ARCHIVE_OK
     on success, ARCHIVE_EOF if no more ACL entries exist and ARCHIVE_WARN if
     archive_entry_acl_reset() has not been called first.

     archive_entry_text_w() returns a wide string representation of the ACL
     entrise matching the given type mask.  The returned long string is valid
     until the next call to archive_entry_acl_clear(),
     archive_entry_acl_add_entry(), archive_entry_acl_add_entry_w() or
     archive_entry_acl_text_w().

SEE ALSO
     archive(3), archive_entry(3)

BUGS
     ARCHIVE_ENTRY_ACL_STYLE_EXTRA_ID and ARCHIVE_ENTRY_ACL_STYLE_MARK_DEFAULT
     are not documented.

BSD			       February 21, 2010			   BSD
