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diff --git a/Utilities/cmlibarchive/libarchive/archive_write.3 b/Utilities/cmlibarchive/libarchive/archive_write.3 new file mode 100644 index 0000000..1fa4245 --- /dev/null +++ b/Utilities/cmlibarchive/libarchive/archive_write.3 @@ -0,0 +1,261 @@ +.\" Copyright (c) 2003-2011 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: head/lib/libarchive/archive_write.3 201110 2009-12-28 03:31:29Z kientzle $ +.\" +.Dd March 23, 2011 +.Dt archive_write 3 +.Os +.Sh NAME +.Nm archive_write +.Nd functions for creating archives +.Sh SYNOPSIS +.In archive.h +.Sh DESCRIPTION +These functions provide a complete API for creating streaming +archive files. +The general process is to first create the +.Tn struct archive +object, set any desired options, initialize the archive, append entries, then +close the archive and release all resources. +.\" +.Ss Create archive object +See +.Xr archive_write_new 3 . +.Pp +To write an archive, you must first obtain an initialized +.Tn struct archive +object from +.Fn archive_write_new . +.\" +.Ss Enable filters and formats, configure block size and padding +See +.Xr archive_write_filter 3 , +.Xr archive_write_format 3 +and +.Xr archive_write_blocksize 3 . +.Pp +You can then modify this object for the desired operations with the +various +.Fn archive_write_set_XXX +functions. +In particular, you will need to invoke appropriate +.Fn archive_write_add_XXX +and +.Fn archive_write_set_XXX +functions to enable the corresponding compression and format +support. +.\" +.Ss Set options +See +.Xr archive_read_set_options 3 . +.\" +.Ss Open archive +See +.Xr archive_write_open 3 . +.Pp +Once you have prepared the +.Tn struct archive +object, you call +.Fn archive_write_open +to actually open the archive and prepare it for writing. +There are several variants of this function; +the most basic expects you to provide pointers to several +functions that can provide blocks of bytes from the archive. +There are convenience forms that allow you to +specify a filename, file descriptor, +.Ft "FILE *" +object, or a block of memory from which to write the archive data. +.\" +.Ss Produce archive +See +.Xr archive_write_header 3 +and +.Xr archive_write_data 3 . +.Pp +Individual archive entries are written in a three-step +process: +You first initialize a +.Tn struct archive_entry +structure with information about the new entry. +At a minimum, you should set the pathname of the +entry and provide a +.Va struct stat +with a valid +.Va st_mode +field, which specifies the type of object and +.Va st_size +field, which specifies the size of the data portion of the object. +.\" +.Ss Release resources +See +.Xr archive_write_free 3 . +.Pp +After all entries have been written, use the +.Fn archive_write_free +function to release all resources. +.\" +.Sh EXAMPLE +The following sketch illustrates basic usage of the library. +In this example, +the callback functions are simply wrappers around the standard +.Xr open 2 , +.Xr write 2 , +and +.Xr close 2 +system calls. +.Bd -literal -offset indent +#ifdef __linux__ +#define _FILE_OFFSET_BITS 64 +#endif +#include <sys/stat.h> +#include <archive.h> +#include <archive_entry.h> +#include <fcntl.h> +#include <stdlib.h> +#include <unistd.h> + +struct mydata { + const char *name; + int fd; +}; + +int +myopen(struct archive *a, void *client_data) +{ + struct mydata *mydata = client_data; + + mydata->fd = open(mydata->name, O_WRONLY | O_CREAT, 0644); + if (mydata->fd >= 0) + return (ARCHIVE_OK); + else + return (ARCHIVE_FATAL); +} + +ssize_t +mywrite(struct archive *a, void *client_data, const void *buff, size_t n) +{ + struct mydata *mydata = client_data; + + return (write(mydata->fd, buff, n)); +} + +int +myclose(struct archive *a, void *client_data) +{ + struct mydata *mydata = client_data; + + if (mydata->fd > 0) + close(mydata->fd); + return (0); +} + +void +write_archive(const char *outname, const char **filename) +{ + struct mydata *mydata = malloc(sizeof(struct mydata)); + struct archive *a; + struct archive_entry *entry; + struct stat st; + char buff[8192]; + int len; + int fd; + + a = archive_write_new(); + mydata->name = outname; + archive_write_add_filter_gzip(a); + archive_write_set_format_ustar(a); + archive_write_open(a, mydata, myopen, mywrite, myclose); + while (*filename) { + stat(*filename, &st); + entry = archive_entry_new(); + archive_entry_copy_stat(entry, &st); + archive_entry_set_pathname(entry, *filename); + archive_write_header(a, entry); + if ((fd = open(*filename, O_RDONLY)) != -1) { + len = read(fd, buff, sizeof(buff)); + while ( len > 0 ) { + archive_write_data(a, buff, len); + len = read(fd, buff, sizeof(buff)); + } + close(fd); + } + archive_entry_free(entry); + filename++; + } + archive_write_free(a); +} + +int main(int argc, const char **argv) +{ + const char *outname; + argv++; + outname = argv++; + write_archive(outname, argv); + return 0; +} +.Ed +.Sh SEE ALSO +.Xr tar 1 , +.Xr libarchive 3 , +.Xr archive_write_set_options 3 , +.Xr cpio 5 , +.Xr mtree 5 , +.Xr tar 5 +.Sh HISTORY +The +.Nm libarchive +library first appeared in +.Fx 5.3 . +.Sh AUTHORS +.An -nosplit +The +.Nm libarchive +library was written by +.An Tim Kientzle Aq kientzle@acm.org . +.Sh BUGS +There are many peculiar bugs in historic tar implementations that may cause +certain programs to reject archives written by this library. +For example, several historic implementations calculated header checksums +incorrectly and will thus reject valid archives; GNU tar does not fully support +pax interchange format; some old tar implementations required specific +field terminations. +.Pp +The default pax interchange format eliminates most of the historic +tar limitations and provides a generic key/value attribute facility +for vendor-defined extensions. +One oversight in POSIX is the failure to provide a standard attribute +for large device numbers. +This library uses +.Dq SCHILY.devminor +and +.Dq SCHILY.devmajor +for device numbers that exceed the range supported by the backwards-compatible +ustar header. +These keys are compatible with Joerg Schilling's +.Nm star +archiver. +Other implementations may not recognize these keys and will thus be unable +to correctly restore device nodes with large device numbers from archives +created by this library. |