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diff --git a/Utilities/cmlibarchive/libarchive/archive_write_disk.3 b/Utilities/cmlibarchive/libarchive/archive_write_disk.3 new file mode 100644 index 000000000..ffadb04fe --- /dev/null +++ b/Utilities/cmlibarchive/libarchive/archive_write_disk.3 @@ -0,0 +1,401 @@ +.\" Copyright (c) 2003-2007 Tim Kientzle +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD: src/lib/libarchive/archive_write_disk.3,v 1.4 2008/09/04 05:22:00 kientzle Exp $ +.\" +.Dd August 5, 2008 +.Dt ARCHIVE_WRITE_DISK 3 +.Os +.Sh NAME +.Nm archive_write_disk_new , +.Nm archive_write_disk_set_options , +.Nm archive_write_disk_set_skip_file , +.Nm archive_write_disk_set_group_lookup , +.Nm archive_write_disk_set_standard_lookup , +.Nm archive_write_disk_set_user_lookup , +.Nm archive_write_header , +.Nm archive_write_data , +.Nm archive_write_data_block , +.Nm archive_write_finish_entry , +.Nm archive_write_close , +.Nm archive_write_finish +.Nm archive_write_free +.Nd functions for creating objects on disk +.Sh SYNOPSIS +.In archive.h +.Ft struct archive * +.Fn archive_write_disk_new "void" +.Ft int +.Fn archive_write_disk_set_options "struct archive *" "int flags" +.Ft int +.Fn archive_write_disk_set_skip_file "struct archive *" "dev_t" "ino_t" +.Ft int +.Fo archive_write_disk_set_group_lookup +.Fa "struct archive *" +.Fa "void *" +.Fa "gid_t (*)(void *, const char *gname, gid_t gid)" +.Fa "void (*cleanup)(void *)" +.Fc +.Ft int +.Fn archive_write_disk_set_standard_lookup "struct archive *" +.Ft int +.Fo archive_write_disk_set_user_lookup +.Fa "struct archive *" +.Fa "void *" +.Fa "uid_t (*)(void *, const char *uname, uid_t uid)" +.Fa "void (*cleanup)(void *)" +.Fc +.Ft int +.Fn archive_write_header "struct archive *" "struct archive_entry *" +.Ft ssize_t +.Fn archive_write_data "struct archive *" "const void *" "size_t" +.Ft ssize_t +.Fn archive_write_data_block "struct archive *" "const void *" "size_t size" "int64_t offset" +.Ft int +.Fn archive_write_finish_entry "struct archive *" +.Ft int +.Fn archive_write_close "struct archive *" +.Ft int +.Fn archive_write_finish "struct archive *" +.Ft int +.Fn archive_write_free "struct archive *" +.Sh DESCRIPTION +These functions provide a complete API for creating objects on +disk from +.Tn struct archive_entry +descriptions. +They are most naturally used when extracting objects from an archive +using the +.Fn archive_read +interface. +The general process is to read +.Tn struct archive_entry +objects from an archive, then write those objects to a +.Tn struct archive +object created using the +.Fn archive_write_disk +family functions. +This interface is deliberately very similar to the +.Fn archive_write +interface used to write objects to a streaming archive. +.Bl -tag -width indent +.It Fn archive_write_disk_new +Allocates and initializes a +.Tn struct archive +object suitable for writing objects to disk. +.It Fn archive_write_disk_set_skip_file +Records the device and inode numbers of a file that should not be +overwritten. +This is typically used to ensure that an extraction process does not +overwrite the archive from which objects are being read. +This capability is technically unnecessary but can be a significant +performance optimization in practice. +.It Fn archive_write_disk_set_options +The options field consists of a bitwise OR of one or more of the +following values: +.Bl -tag -compact -width "indent" +.It Cm ARCHIVE_EXTRACT_OWNER +The user and group IDs should be set on the restored file. +By default, the user and group IDs are not restored. +.It Cm ARCHIVE_EXTRACT_PERM +Full permissions (including SGID, SUID, and sticky bits) should +be restored exactly as specified, without obeying the +current umask. +Note that SUID and SGID bits can only be restored if the +user and group ID of the object on disk are correct. +If +.Cm ARCHIVE_EXTRACT_OWNER +is not specified, then SUID and SGID bits will only be restored +if the default user and group IDs of newly-created objects on disk +happen to match those specified in the archive entry. +By default, only basic permissions are restored, and umask is obeyed. +.It Cm ARCHIVE_EXTRACT_TIME +The timestamps (mtime, ctime, and atime) should be restored. +By default, they are ignored. +Note that restoring of atime is not currently supported. +.It Cm ARCHIVE_EXTRACT_NO_OVERWRITE +Existing files on disk will not be overwritten. +By default, existing regular files are truncated and overwritten; +existing directories will have their permissions updated; +other pre-existing objects are unlinked and recreated from scratch. +.It Cm ARCHIVE_EXTRACT_UNLINK +Existing files on disk will be unlinked before any attempt to +create them. +In some cases, this can prove to be a significant performance improvement. +By default, existing files are truncated and rewritten, but +the file is not recreated. +In particular, the default behavior does not break existing hard links. +.It Cm ARCHIVE_EXTRACT_ACL +Attempt to restore ACLs. +By default, extended ACLs are ignored. +.It Cm ARCHIVE_EXTRACT_FFLAGS +Attempt to restore extended file flags. +By default, file flags are ignored. +.It Cm ARCHIVE_EXTRACT_XATTR +Attempt to restore POSIX.1e extended attributes. +By default, they are ignored. +.It Cm ARCHIVE_EXTRACT_SECURE_SYMLINKS +Refuse to extract any object whose final location would be altered +by a symlink on disk. +This is intended to help guard against a variety of mischief +caused by archives that (deliberately or otherwise) extract +files outside of the current directory. +The default is not to perform this check. +If +.Cm ARCHIVE_EXTRACT_UNLINK +is specified together with this option, the library will +remove any intermediate symlinks it finds and return an +error only if such symlink could not be removed. +.It Cm ARCHIVE_EXTRACT_SECURE_NODOTDOT +Refuse to extract a path that contains a +.Pa .. +element anywhere within it. +The default is to not refuse such paths. +Note that paths ending in +.Pa .. +always cause an error, regardless of this flag. +.It Cm ARCHIVE_EXTRACT_SPARSE +Scan data for blocks of NUL bytes and try to recreate them with holes. +This results in sparse files, independent of whether the archive format +supports or uses them. +.El +.It Xo +.Fn archive_write_disk_set_group_lookup , +.Fn archive_write_disk_set_user_lookup +.Xc +The +.Tn struct archive_entry +objects contain both names and ids that can be used to identify users +and groups. +These names and ids describe the ownership of the file itself and +also appear in ACL lists. +By default, the library uses the ids and ignores the names, but +this can be overridden by registering user and group lookup functions. +To register, you must provide a lookup function which +accepts both a name and id and returns a suitable id. +You may also provide a +.Tn void * +pointer to a private data structure and a cleanup function for +that data. +The cleanup function will be invoked when the +.Tn struct archive +object is destroyed. +.It Fn archive_write_disk_set_standard_lookup +This convenience function installs a standard set of user +and group lookup functions. +These functions use +.Xr getpwnam 3 +and +.Xr getgrnam 3 +to convert names to ids, defaulting to the ids if the names cannot +be looked up. +These functions also implement a simple memory cache to reduce +the number of calls to +.Xr getpwnam 3 +and +.Xr getgrnam 3 . +.It Fn archive_write_header +Build and write a header using the data in the provided +.Tn struct archive_entry +structure. +See +.Xr archive_entry 3 +for information on creating and populating +.Tn struct archive_entry +objects. +.It Fn archive_write_data +Write data corresponding to the header just written. +Returns number of bytes written or -1 on error. +.It Fn archive_write_data_block +Write data corresponding to the header just written. +This is like +.Fn archive_write_data +except that it performs a seek on the file being +written to the specified offset before writing the data. +This is useful when restoring sparse files from archive +formats that support sparse files. +Returns number of bytes written or -1 on error. +(Note: This is currently not supported for +.Tn archive_write +handles, only for +.Tn archive_write_disk +handles.) +.It Fn archive_write_finish_entry +Close out the entry just written. +Ordinarily, clients never need to call this, as it +is called automatically by +.Fn archive_write_next_header +and +.Fn archive_write_close +as needed. +However, some file attributes are written to disk only +after the file is closed, so this can be necessary +if you need to work with the file on disk right away. +.It Fn archive_write_close +Set any attributes that could not be set during the initial restore. +For example, directory timestamps are not restored initially because +restoring a subsequent file would alter that timestamp. +Similarly, non-writable directories are initially created with +write permissions (so that their contents can be restored). +The +.Nm +library maintains a list of all such deferred attributes and +sets them when this function is invoked. +.It Fn archive_write_finish +This is a deprecated synonym for +.Fn archive_write_free . +.It Fn archive_write_free +Invokes +.Fn archive_write_close +if it was not invoked manually, then releases all resources. +.El +More information about the +.Va struct archive +object and the overall design of the library can be found in the +.Xr libarchive 3 +overview. +Many of these functions are also documented under +.Xr archive_write 3 . +.Sh RETURN VALUES +Most functions return +.Cm ARCHIVE_OK +(zero) on success, or one of several non-zero +error codes for errors. +Specific error codes include: +.Cm ARCHIVE_RETRY +for operations that might succeed if retried, +.Cm ARCHIVE_WARN +for unusual conditions that do not prevent further operations, and +.Cm ARCHIVE_FATAL +for serious errors that make remaining operations impossible. +.Pp +.Fn archive_write_disk_new +returns a pointer to a newly-allocated +.Tn struct archive +object. +.Pp +.Fn archive_write_data +returns a count of the number of bytes actually written, +or +.Li -1 +on error. +.\" +.Sh ERRORS +Detailed error codes and textual descriptions are available from the +.Fn archive_errno +and +.Fn archive_error_string +functions. +.\" +.Sh SEE ALSO +.Xr archive_read 3 , +.Xr archive_write 3 , +.Xr tar 1 , +.Xr libarchive 3 +.Sh HISTORY +The +.Nm libarchive +library first appeared in +.Fx 5.3 . +The +.Nm archive_write_disk +interface was added to +.Nm libarchive 2.0 +and first appeared in +.Fx 6.3 . +.Sh AUTHORS +.An -nosplit +The +.Nm libarchive +library was written by +.An Tim Kientzle Aq kientzle@acm.org . +.Sh BUGS +Directories are actually extracted in two distinct phases. +Directories are created during +.Fn archive_write_header , +but final permissions are not set until +.Fn archive_write_close . +This separation is necessary to correctly handle borderline +cases such as a non-writable directory containing +files, but can cause unexpected results. +In particular, directory permissions are not fully +restored until the archive is closed. +If you use +.Xr chdir 2 +to change the current directory between calls to +.Fn archive_read_extract +or before calling +.Fn archive_read_close , +you may confuse the permission-setting logic with +the result that directory permissions are restored +incorrectly. +.Pp +The library attempts to create objects with filenames longer than +.Cm PATH_MAX +by creating prefixes of the full path and changing the current directory. +Currently, this logic is limited in scope; the fixup pass does +not work correctly for such objects and the symlink security check +option disables the support for very long pathnames. +.Pp +Restoring the path +.Pa aa/../bb +does create each intermediate directory. +In particular, the directory +.Pa aa +is created as well as the final object +.Pa bb . +In theory, this can be exploited to create an entire directory hierarchy +with a single request. +Of course, this does not work if the +.Cm ARCHIVE_EXTRACT_NODOTDOT +option is specified. +.Pp +Implicit directories are always created obeying the current umask. +Explicit objects are created obeying the current umask unless +.Cm ARCHIVE_EXTRACT_PERM +is specified, in which case they current umask is ignored. +.Pp +SGID and SUID bits are restored only if the correct user and +group could be set. +If +.Cm ARCHIVE_EXTRACT_OWNER +is not specified, then no attempt is made to set the ownership. +In this case, SGID and SUID bits are restored only if the +user and group of the final object happen to match those specified +in the entry. +.Pp +The +.Dq standard +user-id and group-id lookup functions are not the defaults because +.Xr getgrnam 3 +and +.Xr getpwnam 3 +are sometimes too large for particular applications. +The current design allows the application author to use a more +compact implementation when appropriate. +.Pp +There should be a corresponding +.Nm archive_read_disk +interface that walks a directory hierarchy and returns archive +entry objects. |