diff options
Diffstat (limited to 'archivers/libarchive/files/doc/man/archive_write_disk.3')
| -rw-r--r-- | archivers/libarchive/files/doc/man/archive_write_disk.3 | 450 |
1 files changed, 278 insertions, 172 deletions
diff --git a/archivers/libarchive/files/doc/man/archive_write_disk.3 b/archivers/libarchive/files/doc/man/archive_write_disk.3 index 880a399b949..4e81e1caec8 100644 --- a/archivers/libarchive/files/doc/man/archive_write_disk.3 +++ b/archivers/libarchive/files/doc/man/archive_write_disk.3 @@ -1,145 +1,190 @@ -.\" 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 1.1 2007/03/03 07:37:36 kientzle Exp $ -.\" -.Dd March 2, 2007 -.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_finish_entry , -.Nm archive_write_close , -.Nm archive_write_finish -.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 -.Fn archive_write_disk_set_group_lookup "struct archive *" "void *" "gid_t (*)(void *, const char *gname, gid_t gid)" "void (*cleanup)(void *)" -.Ft int -.Fn archive_write_disk_set_standard_lookup "struct archive *" -.Ft int -.Fn archive_write_disk_set_user_lookup "struct archive *" "void *" "uid_t (*)(void *, const char *uname, uid_t uid)" "void (*cleanup)(void *)" -.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 int -.Fn archive_write_finish_entry "struct archive *" -.Ft int -.Fn archive_write_close "struct archive *" -.Ft int -.Fn archive_write_finish "struct archive *" -.Sh DESCRIPTION +.TH archive_write_disk 3 "March 2, 2007" "" +.SH NAME +\fBarchive_write_disk_new\fP, +\fBarchive_write_disk_set_options\fP, +\fBarchive_write_disk_set_skip_file\fP, +\fBarchive_write_disk_set_group_lookup\fP, +\fBarchive_write_disk_set_standard_lookup\fP, +\fBarchive_write_disk_set_user_lookup\fP, +\fBarchive_write_header\fP, +\fBarchive_write_data\fP, +\fBarchive_write_finish_entry\fP, +\fBarchive_write_close\fP, +\fBarchive_write_finish\fP +\- functions for creating objects on disk +.SH SYNOPSIS +\fB#include <archive.h>\fP +.br +\fIstruct archive *\fP +.RE +.nh +\fBarchive_write_disk_new\fP +.hy +("void"); +\fIint\fP +.RE +.nh +\fBarchive_write_disk_set_options\fP +.hy +("struct archive *" "int flags"); +\fIint\fP +.RE +.nh +\fBarchive_write_disk_set_skip_file\fP +.hy +("struct archive *" "dev_t" "ino_t"); +\fIint\fP +.RE +.nh +\fBarchive_write_disk_set_group_lookup\fP +.hy +("struct archive *" "void *" "gid_t (*)(void *, const char *gname, gid_t gid)" "void (*cleanup)(void *)"); +\fIint\fP +.RE +.nh +\fBarchive_write_disk_set_standard_lookup\fP +.hy +("struct archive *"); +\fIint\fP +.RE +.nh +\fBarchive_write_disk_set_user_lookup\fP +.hy +("struct archive *" "void *" "uid_t (*)(void *, const char *uname, uid_t uid)" "void (*cleanup)(void *)"); +\fIint\fP +.RE +.nh +\fBarchive_write_header\fP +.hy +("struct archive *" "struct archive_entry *"); +\fIssize_t\fP +.RE +.nh +\fBarchive_write_data\fP +.hy +("struct archive *" "const void *" "size_t"); +\fIint\fP +.RE +.nh +\fBarchive_write_finish_entry\fP +.hy +("struct archive *"); +\fIint\fP +.RE +.nh +\fBarchive_write_close\fP +.hy +("struct archive *"); +\fIint\fP +.RE +.nh +\fBarchive_write_finish\fP +.hy +("struct archive *"); +.SH DESCRIPTION These functions provide a complete API for creating objects on disk from -.Tn struct archive_entry +Tn struct archive_entry descriptions. They are most naturally used when extracting objects from an archive using the -.Fn archive_read +.nh +\fBarchive_read\fP +.hy +(); interface. The general process is to read -.Tn struct archive_entry +Tn struct archive_entry objects from an archive, then write those objects to a -.Tn struct archive +Tn struct archive object created using the -.Fn archive_write_disk +.nh +\fBarchive_write_disk\fP +.hy +(); family functions. This interface is deliberately very similar to the -.Fn archive_write +.nh +\fBarchive_write\fP +.hy +(); interface used to write objects to a streaming archive. -.Bl -tag -width indent -.It Fn archive_write_disk_new +.TP +.nh +\fBarchive_write_disk_new\fP +.hy +(); Allocates and initializes a -.Tn struct archive +Tn struct archive object suitable for writing objects to disk. -.It Fn archive_write_disk_set_skip_file +.TP +.nh +\fBarchive_write_disk_set_skip_file\fP +.hy +(); 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 +.TP +.nh +\fBarchive_write_disk_set_options\fP +.hy +(); 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 +.TP +\fBARCHIVE_EXTRACT_OWNER\fP 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 +.TP +\fBARCHIVE_EXTRACT_PERM\fP 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 +\fBARCHIVE_EXTRACT_OWNER\fP 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 +.TP +\fBARCHIVE_EXTRACT_TIME\fP 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 +.TP +\fBARCHIVE_EXTRACT_NO_OVERWRITE\fP 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 +.TP +\fBARCHIVE_EXTRACT_UNLINK\fP 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 +.TP +\fBARCHIVE_EXTRACT_ACL\fP Attempt to restore ACLs. By default, extended ACLs are ignored. -.It Cm ARCHIVE_EXTRACT_FFLAGS +.TP +\fBARCHIVE_EXTRACT_FFLAGS\fP Attempt to restore extended file flags. By default, file flags are ignored. -.It Cm ARCHIVE_EXTRACT_XATTR +.TP +\fBARCHIVE_EXTRACT_XATTR\fP Attempt to restore POSIX.1e extended attributes. By default, they are ignored. -.It Cm ARCHIVE_EXTRACT_SECURE_SYMLINKS +.TP +\fBARCHIVE_EXTRACT_SECURE_SYMLINKS\fP 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 @@ -147,22 +192,29 @@ 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 +\fBARCHIVE_EXTRACT_UNLINK\fP 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 +.TP +\fBARCHIVE_EXTRACT_SECURE_NODOTDOT\fP Refuse to extract a path that contains a -.Pa .. +\fI\& ..\fP element anywhere within it. The default is to not refuse such paths. Note that paths ending in -.Pa .. +\fI\& ..\fP always cause an error, regardless of this flag. -.El -.It Fn archive_write_disk_set_group_lookup , Fn archive_write_disk_set_user_lookup +.TP +.nh +\fBarchive_write_disk_set_group_lookup\fP +.hy +(, .nh); +\fBarchive_write_disk_set_user_lookup\fP +.hy +(); The -.Tn struct archive_entry +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 @@ -172,187 +224,241 @@ 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 * +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 +Tn struct archive object is destroyed. -.It Fn archive_write_disk_set_standard_lookup +.TP +.nh +\fBarchive_write_disk_set_standard_lookup\fP +.hy +(); This convenience function installs a standard set of user and group lookup functions. These functions use -.Xr getpwnam 3 +\fBgetpwnam\fP(3) and -.Xr getgrnam 3 +\fBgetgrnam\fP(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 +\fBgetpwnam\fP(3) and -.Xr getgrnam 3 . -.It Fn archive_write_header +\fBgetgrnam\fP(3). +.TP +.nh +\fBarchive_write_header\fP +.hy +(); Build and write a header using the data in the provided -.Tn struct archive_entry +Tn struct archive_entry structure. See -.Xr archive_entry 3 +\fBarchive_entry\fP(3) for information on creating and populating -.Tn struct archive_entry +Tn struct archive_entry objects. -.It Fn archive_write_data +.TP +.nh +\fBarchive_write_data\fP +.hy +(); Write data corresponding to the header just written. Returns number of bytes written or -1 on error. -.It Fn archive_write_finish_entry +.TP +.nh +\fBarchive_write_finish_entry\fP +.hy +(); Close out the entry just written. Ordinarily, clients never need to call this, as it is called automatically by -.Fn archive_write_next_header +.nh +\fBarchive_write_next_header\fP +.hy +(); and -.Fn archive_write_close +.nh +\fBarchive_write_close\fP +.hy +(); as needed. -.It Fn archive_write_close +.TP +.nh +\fBarchive_write_close\fP +.hy +(); 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 +\fBarchive_write_disk_new\fP library maintains a list of all such deferred attributes and sets them when this function is invoked. -.It Fn archive_write_finish +.TP +.nh +\fBarchive_write_finish\fP +.hy +(); Invokes -.Fn archive_write_close +.nh +\fBarchive_write_close\fP +.hy +(); if it was not invoked manually, then releases all resources. -.El More information about the -.Va struct archive +\fIstruct\fP archive object and the overall design of the library can be found in the -.Xr libarchive 3 +\fBlibarchive\fP(3) overview. Many of these functions are also documented under -.Xr archive_write 3 . -.Sh RETURN VALUES +\fBarchive_write\fP(3). +.SH RETURN VALUES Most functions return -.Cm ARCHIVE_OK +\fBARCHIVE_OK\fP (zero) on success, or one of several non-zero error codes for errors. Specific error codes include: -.Cm ARCHIVE_RETRY +\fBARCHIVE_RETRY\fP for operations that might succeed if retried, -.Cm ARCHIVE_WARN +\fBARCHIVE_WARN\fP for unusual conditions that do not prevent further operations, and -.Cm ARCHIVE_FATAL +\fBARCHIVE_FATAL\fP for serious errors that make remaining operations impossible. The -.Fn archive_errno +.nh +\fBarchive_errno\fP +.hy +(); and -.Fn archive_error_string +.nh +\fBarchive_error_string\fP +.hy +(); functions can be used to retrieve an appropriate error code and a textual error message. -.Pp -.Fn archive_write_disk_new +.nh +\fBarchive_write_disk_new\fP +.hy +(); returns a pointer to a newly-allocated -.Tn struct archive +Tn struct archive object. -.Pp -.Fn archive_write_data +.nh +\fBarchive_write_data\fP +.hy +(); returns a count of the number of bytes actually written. On error, -1 is returned and the -.Fn archive_errno +.nh +\fBarchive_errno\fP +.hy +(); and -.Fn archive_error_string +.nh +\fBarchive_error_string\fP +.hy +(); functions will return appropriate values. -.Sh SEE ALSO -.Xr archive_read 3 , -.Xr archive_write 3 , -.Xr tar 1 , -.Xr libarchive 3 -.Sh HISTORY +.SH SEE ALSO +\fBarchive_read\fP(3), +\fBarchive_write\fP(3), +\fBtar\fP(1), +\fBlibarchive\fP(3) +.SH HISTORY The -.Nm libarchive +\fBlibarchive\fP library first appeared in -.Fx 5.3 . +FreeBSD 5.3. The -.Nm archive_write_disk +\fBarchive_write_disk\fP interface was added to -.Nm libarchive 2.0 +\fBlibarchive\fP 2.0 and first appeared in -.Fx 6.3 . -.Sh AUTHORS -.An -nosplit +FreeBSD 6.3. +.SH AUTHORS +-nosplit The -.Nm libarchive +\fBlibarchive\fP library was written by -.An Tim Kientzle Aq kientzle@acm.org . -.Sh BUGS +Tim Kientzle <kientzle@acm.org.> +.SH BUGS Directories are actually extracted in two distinct phases. Directories are created during -.Fn archive_write_header , +.nh +\fBarchive_write_header\fP +.hy +(,); but final permissions are not set until -.Fn archive_write_close . +.nh +\fBarchive_write_close\fP +.hy +(.); 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 +\fBchdir\fP(2) to change the current directory between calls to -.Fn archive_read_extract +.nh +\fBarchive_read_extract\fP +.hy +(); or before calling -.Fn archive_read_close , +.nh +\fBarchive_read_close\fP +.hy +(,); 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 +\fBPATH_MAX\fP 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 +\fIaa/../bb\fP does create each intermediate directory. In particular, the directory -.Pa aa +\fIaa\fP is created as well as the final object -.Pa bb . +\fIbb\fP. In theory, this can be exploited to create an entire directory heirarchy with a single request. Of course, this does not work if the -.Cm ARCHIVE_EXTRACT_NODOTDOT +\fBARCHIVE_EXTRACT_NODOTDOT\fP 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 +\fBARCHIVE_EXTRACT_PERM\fP 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 +\fBARCHIVE_EXTRACT_OWNER\fP 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 +``standard'' user-id and group-id lookup functions are not the defaults because -.Xr getgrnam 3 +\fBgetgrnam\fP(3) and -.Xr getpwnam 3 +\fBgetpwnam\fP(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 +\fBarchive_read_disk\fP interface that walks a directory heirarchy and returns archive -entry objects.
\ No newline at end of file +entry objects. |