libarchive/archive_entry_perms.3

.\" Copyright (c) 2003-2007 Tim Kientzle
.\" Copyright (c) 2010 Joerg Sonnenberger
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.Dd February 2, 2012
.Dt ARCHIVE_ENTRY_PERMS 3
.Os
.Sh NAME
.Nm archive_entry_gid ,
.Nm archive_entry_set_gid ,
.Nm archive_entry_uid ,
.Nm archive_entry_set_uid ,
.Nm archive_entry_perm ,
.Nm archive_entry_set_perm ,
.Nm archive_entry_strmode ,
.Nm archive_entry_uname
.Nm archive_entry_uname_w
.Nm archive_entry_set_uname ,
.Nm archive_entry_copy_uname ,
.Nm archive_entry_copy_uname_w ,
.Nm archive_entry_update_uname_utf8 ,
.Nm archive_entry_gname ,
.Nm archive_entry_gname_w ,
.Nm archive_entry_set_gname ,
.Nm archive_entry_copy_gname ,
.Nm archive_entry_copy_gname_w ,
.Nm archive_entry_update_gname_utf8 ,
.Nm archive_entry_fflags ,
.Nm archive_entry_fflags_text ,
.Nm archive_entry_set_fflags ,
.Nm archive_entry_copy_fflags_text ,
.Nm archive_entry_copy_fflags_text_w
.Nd functions for manipulating ownership and permissions in archive entry descriptions
.Sh LIBRARY
Streaming Archive Library (libarchive, -larchive)
.Sh SYNOPSIS
.In archive_entry.h
.Ft gid_t
.Fn archive_entry_gid "struct archive_entry *a"
.Ft void
.Fn archive_entry_set_gid "struct archive_entry *a" "gid_t gid"
.Ft uid_t
.Fn archive_entry_uid "struct archive_entry *a"
.Ft void
.Fn archive_entry_set_uid "struct archive_entry *a" "uid_t uid"
.Ft mode_t
.Fn archive_entry_perm "struct archive_entry *a"
.Ft void
.Fn archive_entry_set_perm "struct archive_entry *a" "mode_t mode"
.Ft const char *
.Fn archive_entry_strmode "struct archive_entry *a"
.Ft const char *
.Fn archive_entry_gname "struct archive_entry *a"
.Ft const wchar_t *
.Fn archive_entry_gname_w "struct archive_entry *a"
.Ft void
.Fn archive_entry_set_gname "struct archive_entry *a" "const char *a"
.Ft void
.Fn archive_entry_copy_gname "struct archive_entry *a" "const char *name"
.Ft void
.Fn archive_entry_copy_gname_w "struct archive_entry *a" "const wchar_t *name"
.Ft int
.Fn archive_entry_update_gname_utf8 "struct archive_entry *a" "const char *name"
.Ft const char *
.Fn archive_entry_uname "struct archive_entry *a"
.Ft const wchar_t *
.Fn archive_entry_uname_w "struct archive_entry *a"
.Ft void
.Fn archive_entry_set_uname "struct archive_entry *a" "const char *name"
.Ft void
.Fn archive_entry_copy_uname "struct archive_entry *a" "const char *name"
.Ft void
.Fn archive_entry_copy_uname_w "struct archive_entry *a" "const wchar_t *name"
.Ft int
.Fn archive_entry_update_uname_utf8 "struct archive_entry *a" "const char *name"
.Ft void
.Fo archive_entry_fflags
.Fa "struct archive_entry *a"
.Fa "unsigned long *set_bits"
.Fa "unsigned long *clear_bits"
.Fc
.Ft const char *
.Fn archive_entry_fflags_text "struct archive_entry *a"
.Ft void
.Fo archive_entry_set_fflags
.Fa "struct archive_entry *a"
.Fa "unsigned long set_bits"
.Fa "unsigned long clear_bits"
.Fc
.Ft const char *
.Fn archive_entry_copy_fflags_text "struct archive_entry *a" "const char *text"
.Ft const wchar_t *
.Fn archive_entry_copy_fflags_text_w "struct archive_entry *a" "const wchar_t *text"
.Sh DESCRIPTION
.Ss User id, group id and mode
The functions
.Fn archive_entry_uid ,
.Fn archive_entry_gid ,
and
.Fn archive_entry_perm
can be used to extract the user id, group id and permission from the given entry.
The corresponding functions
.Fn archive_entry_set_uid ,
.Fn archive_entry_set_gid ,
and
.Fn archive_entry_set_perm
store the given user id, group id and permission in the entry.
The permission is also set as side effect of calling
.Fn archive_entry_set_mode .
.Pp
.Fn archive_entry_strmode
returns a string representation of the permission as used by the long mode of
.Xr ls 1 .
.Ss User and group name
User and group names can be provided in one of three different ways:
.Bl -tag -width "wchar_t *"
.It char *
Multibyte strings in the current locale.
.It wchar_t *
Wide character strings in the current locale.
The accessor functions are named
.Fn XXX_w .
.It UTF-8
Unicode strings encoded as UTF-8.
This are convience functions to update both the multibyte and wide
character strings at the same time.
.El
.Pp
.Fn archive_entry_set_XXX
is an alias for 
.Fn archive_entry_copy_XXX .
.Ss File Flags
File flags are transparently converted between a bitmap
representation and a textual format.
For example, if you set the bitmap and ask for text, the library
will build a canonical text format.
However, if you set a text format and request a text format,
you will get back the same text, even if it is ill-formed.
If you need to canonicalize a textual flags string, you should first set the
text form, then request the bitmap form, then use that to set the bitmap form.
Setting the bitmap format will clear the internal text representation
and force it to be reconstructed when you next request the text form.
.Pp
The bitmap format consists of two integers, one containing bits
that should be set, the other specifying bits that should be
cleared.
Bits not mentioned in either bitmap will be ignored.
Usually, the bitmap of bits to be cleared will be set to zero.
In unusual circumstances, you can force a fully-specified set
of file flags by setting the bitmap of flags to clear to the complement
of the bitmap of flags to set.
(This differs from
.Xr fflagstostr 3 ,
which only includes names for set bits.)
Converting a bitmap to a textual string is a platform-specific
operation; bits that are not meaningful on the current platform
will be ignored.
.Pp
The canonical text format is a comma-separated list of flag names.
The
.Fn archive_entry_copy_fflags_text
and
.Fn archive_entry_copy_fflags_text_w
functions parse the provided text and sets the internal bitmap values.
This is a platform-specific operation; names that are not meaningful
on the current platform will be ignored.
The function returns a pointer to the start of the first name that was not
recognized, or NULL if every name was recognized.
Note that every name \(em including names that follow an unrecognized
name \(em will be evaluated, and the bitmaps will be set to reflect
every name that is recognized.
(In particular, this differs from
.Xr strtofflags 3 ,
which stops parsing at the first unrecognized name.)
.Sh SEE ALSO
.Xr archive_entry 3 ,
.Xr archive_entry_acl 3 ,
.Xr archive_read_disk 3 ,
.Xr archive_write_disk 3
.Xr libarchive 3 ,
.Sh BUGS
The platform types
.Vt uid_t
and
.Vt gid_t
are often 16 or 32 bit wide.
In this case it is possible that the ids can not be correctly restored
from archives and get truncated.