Merge new xz/lzma support from libarchive.googlecode.com.

Since FreeBSD doesn't have liblzma in the base system, the
read side will always fall back to the unxz/unlzma commands for now.
(Which will in turn fail if those commands are not currently
installed.)  The write side does not yet have a fallback, so
that will just fail.

3 files changed, 1083 insertions, 0 deletions

diff --git a/lib/libarchive/Makefile b/lib/libarchive/Makefile
index 4597374..fc1b724 100644
--- a/lib/libarchive/Makefile
+++ b/lib/libarchive/Makefile
@@ -39,6 +39,7 @@ SRCS=	archive_check_magic.c				\
 	archive_read_support_compression_gzip.c		\
 	archive_read_support_compression_none.c		\
 	archive_read_support_compression_program.c	\
+	archive_read_support_compression_xz.c		\
 	archive_read_support_format_all.c		\
 	archive_read_support_format_ar.c		\
 	archive_read_support_format_cpio.c		\
@@ -63,6 +64,7 @@ SRCS=	archive_check_magic.c				\
 	archive_write_set_compression_gzip.c		\
 	archive_write_set_compression_none.c		\
 	archive_write_set_compression_program.c		\
+	archive_write_set_compression_xz.c		\
 	archive_write_set_format.c			\
 	archive_write_set_format_ar.c			\
 	archive_write_set_format_by_name.c		\
diff --git a/lib/libarchive/archive_read_support_compression_xz.c b/lib/libarchive/archive_read_support_compression_xz.c
new file mode 100644
index 0000000..a3c9553
--- /dev/null
+++ b/lib/libarchive/archive_read_support_compression_xz.c
@@ -0,0 +1,642 @@
+/*-
+ * Copyright (c) 2009 Michihiro NAKAJIMA
+ * Copyright (c) 2003-2008 Tim Kientzle and Miklos Vajna
+ * 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(S) ``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(S) 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.
+ */
+
+#include "archive_platform.h"
+
+__FBSDID("$FreeBSD$");
+
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#include <stdio.h>
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if HAVE_LZMA_H
+#include <lzma.h>
+#elif HAVE_LZMADEC_H
+#include <lzmadec.h>
+#endif
+
+#include "archive.h"
+#include "archive_private.h"
+#include "archive_read_private.h"
+
+#if HAVE_LZMA_H && HAVE_LIBLZMA
+
+struct private_data {
+	lzma_stream	 stream;
+	unsigned char	*out_block;
+	size_t		 out_block_size;
+	int64_t		 total_out;
+	char		 eof; /* True = found end of compressed data. */
+};
+
+/* Combined lzma/xz filter */
+static ssize_t	xz_filter_read(struct archive_read_filter *, const void **);
+static int	xz_filter_close(struct archive_read_filter *);
+static int	xz_lzma_bidder_init(struct archive_read_filter *);
+
+#elif HAVE_LZMADEC_H && HAVE_LIBLZMADEC
+
+struct private_data {
+	lzmadec_stream	 stream;
+	unsigned char	*out_block;
+	size_t		 out_block_size;
+	int64_t		 total_out;
+	char		 eof; /* True = found end of compressed data. */
+};
+
+/* Lzma-only filter */
+static ssize_t	lzma_filter_read(struct archive_read_filter *, const void **);
+static int	lzma_filter_close(struct archive_read_filter *);
+#endif
+
+/*
+ * Note that we can detect xz and lzma compressed files even if we
+ * can't decompress them.  (In fact, we like detecting them because we
+ * can give better error messages.)  So the bid framework here gets
+ * compiled even if no lzma library is available.
+ */
+static int	xz_bidder_bid(struct archive_read_filter_bidder *,
+		    struct archive_read_filter *);
+static int	xz_bidder_init(struct archive_read_filter *);
+static int	lzma_bidder_bid(struct archive_read_filter_bidder *,
+		    struct archive_read_filter *);
+static int	lzma_bidder_init(struct archive_read_filter *);
+
+int
+archive_read_support_compression_xz(struct archive *_a)
+{
+	struct archive_read *a = (struct archive_read *)_a;
+	struct archive_read_filter_bidder *bidder = __archive_read_get_bidder(a);
+
+	if (bidder == NULL)
+		return (ARCHIVE_FATAL);
+
+	bidder->data = NULL;
+	bidder->bid = xz_bidder_bid;
+	bidder->init = xz_bidder_init;
+	bidder->options = NULL;
+	bidder->free = NULL;
+#if HAVE_LZMA_H && HAVE_LIBLZMA
+	return (ARCHIVE_OK);
+#else
+	archive_set_error(_a, ARCHIVE_ERRNO_MISC,
+	    "Using external unxz program for xz decompression");
+	return (ARCHIVE_WARN);
+#endif
+}
+
+int
+archive_read_support_compression_lzma(struct archive *_a)
+{
+	struct archive_read *a = (struct archive_read *)_a;
+	struct archive_read_filter_bidder *bidder = __archive_read_get_bidder(a);
+
+	if (bidder == NULL)
+		return (ARCHIVE_FATAL);
+
+	bidder->data = NULL;
+	bidder->bid = lzma_bidder_bid;
+	bidder->init = lzma_bidder_init;
+	bidder->options = NULL;
+	bidder->free = NULL;
+#if HAVE_LZMA_H && HAVE_LIBLZMA
+	return (ARCHIVE_OK);
+#elif HAVE_LZMADEC_H && HAVE_LIBLZMADEC
+	return (ARCHIVE_OK);
+#else
+	archive_set_error(_a, ARCHIVE_ERRNO_MISC,
+	    "Using external unlzma program for lzma decompression");
+	return (ARCHIVE_WARN);
+#endif
+}
+
+/*
+ * Test whether we can handle this data.
+ */
+static int
+xz_bidder_bid(struct archive_read_filter_bidder *self,
+    struct archive_read_filter *filter)
+{
+	const unsigned char *buffer;
+	ssize_t avail;
+	int bits_checked;
+
+	(void)self; /* UNUSED */
+
+	buffer = __archive_read_filter_ahead(filter, 6, &avail);
+	if (buffer == NULL)
+		return (0);
+
+	/*
+	 * Verify Header Magic Bytes : FD 37 7A 58 5A 00
+	 */
+	bits_checked = 0;
+	if (buffer[0] != 0xFD)
+		return (0);
+	bits_checked += 8;
+	if (buffer[1] != 0x37)
+		return (0);
+	bits_checked += 8;
+	if (buffer[2] != 0x7A)
+		return (0);
+	bits_checked += 8;
+	if (buffer[3] != 0x58)
+		return (0);
+	bits_checked += 8;
+	if (buffer[4] != 0x5A)
+		return (0);
+	bits_checked += 8;
+	if (buffer[5] != 0x00)
+		return (0);
+	bits_checked += 8;
+
+	return (bits_checked);
+}
+
+/*
+ * Test whether we can handle this data.
+ *
+ * <sigh> LZMA has a rather poor file signature.  Zeros do not
+ * make good signature bytes as a rule, and the only non-zero byte
+ * here is an ASCII character.  For example, an uncompressed tar
+ * archive whose first file is ']' would satisfy this check.  It may
+ * be necessary to exclude LZMA from compression_all() because of
+ * this.  Clients of libarchive would then have to explicitly enable
+ * LZMA checking instead of (or in addition to) compression_all() when
+ * they have other evidence (file name, command-line option) to go on.
+ */
+static int
+lzma_bidder_bid(struct archive_read_filter_bidder *self,
+    struct archive_read_filter *filter)
+{
+	const unsigned char *buffer;
+	ssize_t avail;
+	int bits_checked;
+
+	(void)self; /* UNUSED */
+
+	buffer = __archive_read_filter_ahead(filter, 6, &avail);
+	if (buffer == NULL)
+		return (0);
+
+	/* First byte of raw LZMA stream is always 0x5d. */
+	bits_checked = 0;
+	if (buffer[0] != 0x5d)
+		return (0);
+	bits_checked += 8;
+
+	/* Second through fifth bytes are dictionary code, stored in
+	 * little-endian order.  The two least-significant bytes are
+	 * always zero. */
+	if (buffer[1] != 0 || buffer[2] != 0)
+		return (0);
+	bits_checked += 16;
+
+	/* ??? TODO:  Fix this. ??? */
+	/* NSIS format check uses this, but I've seen tar.lzma
+	 * archives where this byte is 0xff, not 0.  Can it
+	 * ever be anything other than 0 or 0xff?
+	 */
+#if 0
+	if (buffer[5] != 0)
+		return (0);
+	bits_checked += 8;
+#endif
+
+	/* TODO: The above test is still very weak.  It would be
+	 * good to do better. */
+
+	return (bits_checked);
+}
+
+#if HAVE_LZMA_H && HAVE_LIBLZMA
+
+/*
+ * liblzma 4.999.7 and later support both lzma and xz streams.
+ */
+static int
+xz_bidder_init(struct archive_read_filter *self)
+{
+	self->code = ARCHIVE_COMPRESSION_XZ;
+	self->name = "xz";
+	return (xz_lzma_bidder_init(self));
+}
+
+static int
+lzma_bidder_init(struct archive_read_filter *self)
+{
+	self->code = ARCHIVE_COMPRESSION_LZMA;
+	self->name = "lzma";
+	return (xz_lzma_bidder_init(self));
+}
+
+/*
+ * Setup the callbacks.
+ */
+static int
+xz_lzma_bidder_init(struct archive_read_filter *self)
+{
+	static const size_t out_block_size = 64 * 1024;
+	void *out_block;
+	struct private_data *state;
+	int ret;
+
+	state = (struct private_data *)calloc(sizeof(*state), 1);
+	out_block = (unsigned char *)malloc(out_block_size);
+	if (state == NULL || out_block == NULL) {
+		archive_set_error(&self->archive->archive, ENOMEM,
+		    "Can't allocate data for xz decompression");
+		free(out_block);
+		free(state);
+		return (ARCHIVE_FATAL);
+	}
+
+	self->data = state;
+	state->out_block_size = out_block_size;
+	state->out_block = out_block;
+	self->read = xz_filter_read;
+	self->skip = NULL; /* not supported */
+	self->close = xz_filter_close;
+
+	state->stream.avail_in = 0;
+
+	state->stream.next_out = state->out_block;
+	state->stream.avail_out = state->out_block_size;
+
+	/* Initialize compression library.
+	 * TODO: I don't know what value is best for memlimit.
+	 *       maybe, it needs to check memory size which
+	 *       running system has.
+	 */
+	if (self->code == ARCHIVE_COMPRESSION_XZ)
+		ret = lzma_stream_decoder(&(state->stream),
+		    (1U << 23) + (1U << 21),/* memlimit */
+		    LZMA_CONCATENATED);
+	else
+		ret = lzma_alone_decoder(&(state->stream),
+		    (1U << 23) + (1U << 21));/* memlimit */
+
+	if (ret == LZMA_OK)
+		return (ARCHIVE_OK);
+
+	/* Library setup failed: Choose an error message and clean up. */
+	switch (ret) {
+	case LZMA_MEM_ERROR:
+		archive_set_error(&self->archive->archive, ENOMEM,
+		    "Internal error initializing compression library: "
+		    "Cannot allocate memory");
+		break;
+	case LZMA_OPTIONS_ERROR:
+		archive_set_error(&self->archive->archive,
+		    ARCHIVE_ERRNO_MISC,
+		    "Internal error initializing compression library: "
+		    "Invalid or unsupported options");
+		break;
+	default:
+		archive_set_error(&self->archive->archive, ARCHIVE_ERRNO_MISC,
+		    "Internal error initializing lzma library");
+		break;
+	}
+
+	free(state->out_block);
+	free(state);
+	self->data = NULL;
+	return (ARCHIVE_FATAL);
+}
+
+/*
+ * Return the next block of decompressed data.
+ */
+static ssize_t
+xz_filter_read(struct archive_read_filter *self, const void **p)
+{
+	struct private_data *state;
+	size_t decompressed;
+	ssize_t avail_in;
+	int ret;
+
+	state = (struct private_data *)self->data;
+
+	/* Empty our output buffer. */
+	state->stream.next_out = state->out_block;
+	state->stream.avail_out = state->out_block_size;
+
+	/* Try to fill the output buffer. */
+	while (state->stream.avail_out > 0 && !state->eof) {
+		state->stream.next_in =
+		    __archive_read_filter_ahead(self->upstream, 1, &avail_in);
+		if (state->stream.next_in == NULL && avail_in < 0)
+			return (ARCHIVE_FATAL);
+		state->stream.avail_in = avail_in;
+
+		/* Decompress as much as we can in one pass. */
+		ret = lzma_code(&(state->stream),
+		    (state->stream.avail_in == 0)? LZMA_FINISH: LZMA_RUN);
+		switch (ret) {
+		case LZMA_STREAM_END: /* Found end of stream. */
+			state->eof = 1;
+			/* FALL THROUGH */
+		case LZMA_OK: /* Decompressor made some progress. */
+			__archive_read_filter_consume(self->upstream,
+			    avail_in - state->stream.avail_in);
+			break;
+		case LZMA_MEM_ERROR:
+			archive_set_error(&self->archive->archive, ENOMEM,
+			    "Lzma library error: Cannot allocate memory");
+			return (ARCHIVE_FATAL);
+		case LZMA_MEMLIMIT_ERROR:
+			archive_set_error(&self->archive->archive, ENOMEM,
+			    "Lzma library error: Out of memory");
+			return (ARCHIVE_FATAL);
+		case LZMA_FORMAT_ERROR:
+			archive_set_error(&self->archive->archive,
+			    ARCHIVE_ERRNO_MISC,
+			    "Lzma library error: format not recognized");
+			return (ARCHIVE_FATAL);
+		case LZMA_OPTIONS_ERROR:
+			archive_set_error(&self->archive->archive,
+			    ARCHIVE_ERRNO_MISC,
+			    "Lzma library error: Invalid options");
+			return (ARCHIVE_FATAL);
+		case LZMA_DATA_ERROR:
+			archive_set_error(&self->archive->archive,
+			    ARCHIVE_ERRNO_MISC,
+			    "Lzma library error: Corrupted input data");
+			return (ARCHIVE_FATAL);
+		case LZMA_BUF_ERROR:
+			archive_set_error(&self->archive->archive,
+			    ARCHIVE_ERRNO_MISC,
+			    "Lzma library error:  No progress is possible");
+			return (ARCHIVE_FATAL);
+		default:
+			/* Return an error. */
+			archive_set_error(&self->archive->archive,
+			    ARCHIVE_ERRNO_MISC,
+			    "Lzma decompression failed:  Unknown error");
+			return (ARCHIVE_FATAL);
+		}
+	}
+
+	decompressed = state->stream.next_out - state->out_block;
+	state->total_out += decompressed;
+	if (decompressed == 0)
+		*p = NULL;
+	else
+		*p = state->out_block;
+	return (decompressed);
+}
+
+/*
+ * Clean up the decompressor.
+ */
+static int
+xz_filter_close(struct archive_read_filter *self)
+{
+	struct private_data *state;
+
+	state = (struct private_data *)self->data;
+	lzma_end(&(state->stream));
+	free(state->out_block);
+	free(state);
+	return (ARCHIVE_OK);
+}
+
+#else
+
+#if HAVE_LZMADEC_H && HAVE_LIBLZMADEC
+
+/*
+ * If we have the older liblzmadec library, then we can handle
+ * LZMA streams but not XZ streams.
+ */
+
+/*
+ * Setup the callbacks.
+ */
+static int
+lzma_bidder_init(struct archive_read_filter *self)
+{
+	static const size_t out_block_size = 64 * 1024;
+	void *out_block;
+	struct private_data *state;
+	ssize_t ret, avail_in;
+
+	self->code = ARCHIVE_COMPRESSION_LZMA;
+	self->name = "lzma";
+
+	state = (struct private_data *)calloc(sizeof(*state), 1);
+	out_block = (unsigned char *)malloc(out_block_size);
+	if (state == NULL || out_block == NULL) {
+		archive_set_error(&self->archive->archive, ENOMEM,
+		    "Can't allocate data for lzma decompression");
+		free(out_block);
+		free(state);
+		return (ARCHIVE_FATAL);
+	}
+
+	self->data = state;
+	state->out_block_size = out_block_size;
+	state->out_block = out_block;
+	self->read = lzma_filter_read;
+	self->skip = NULL; /* not supported */
+	self->close = lzma_filter_close;
+
+	/* Prime the lzma library with 18 bytes of input. */
+	state->stream.next_in = (unsigned char *)(uintptr_t)
+	    __archive_read_filter_ahead(self->upstream, 18, &avail_in);
+	if (state->stream.next_in == NULL)
+		return (ARCHIVE_FATAL);
+	state->stream.avail_in = avail_in;
+	state->stream.next_out = state->out_block;
+	state->stream.avail_out = state->out_block_size;
+
+	/* Initialize compression library. */
+	ret = lzmadec_init(&(state->stream));
+	__archive_read_filter_consume(self->upstream,
+	    avail_in - state->stream.avail_in);
+	if (ret == LZMADEC_OK)
+		return (ARCHIVE_OK);
+
+	/* Library setup failed: Clean up. */
+	archive_set_error(&self->archive->archive, ARCHIVE_ERRNO_MISC,
+	    "Internal error initializing lzma library");
+
+	/* Override the error message if we know what really went wrong. */
+	switch (ret) {
+	case LZMADEC_HEADER_ERROR:
+		archive_set_error(&self->archive->archive,
+		    ARCHIVE_ERRNO_MISC,
+		    "Internal error initializing compression library: "
+		    "invalid header");
+		break;
+	case LZMADEC_MEM_ERROR:
+		archive_set_error(&self->archive->archive, ENOMEM,
+		    "Internal error initializing compression library: "
+		    "out of memory");
+		break;
+	}
+
+	free(state->out_block);
+	free(state);
+	self->data = NULL;
+	return (ARCHIVE_FATAL);
+}
+
+/*
+ * Return the next block of decompressed data.
+ */
+static ssize_t
+lzma_filter_read(struct archive_read_filter *self, const void **p)
+{
+	struct private_data *state;
+	size_t decompressed;
+	ssize_t avail_in, ret;
+
+	state = (struct private_data *)self->data;
+
+	/* Empty our output buffer. */
+	state->stream.next_out = state->out_block;
+	state->stream.avail_out = state->out_block_size;
+
+	/* Try to fill the output buffer. */
+	while (state->stream.avail_out > 0 && !state->eof) {
+		state->stream.next_in = (unsigned char *)(uintptr_t)
+		    __archive_read_filter_ahead(self->upstream, 1, &avail_in);
+		if (state->stream.next_in == NULL && avail_in < 0)
+			return (ARCHIVE_FATAL);
+		state->stream.avail_in = avail_in;
+
+		/* Decompress as much as we can in one pass. */
+		ret = lzmadec_decode(&(state->stream), avail_in == 0);
+		switch (ret) {
+		case LZMADEC_STREAM_END: /* Found end of stream. */
+			state->eof = 1;
+			/* FALL THROUGH */
+		case LZMADEC_OK: /* Decompressor made some progress. */
+			__archive_read_filter_consume(self->upstream,
+			    avail_in - state->stream.avail_in);
+			break;
+		case LZMADEC_BUF_ERROR: /* Insufficient input data? */
+			archive_set_error(&self->archive->archive,
+			    ARCHIVE_ERRNO_MISC,
+			    "Insufficient compressed data");
+			return (ARCHIVE_FATAL);
+		default:
+			/* Return an error. */
+			archive_set_error(&self->archive->archive,
+			    ARCHIVE_ERRNO_MISC,
+			    "Lzma decompression failed");
+			return (ARCHIVE_FATAL);
+		}
+	}
+
+	decompressed = state->stream.next_out - state->out_block;
+	state->total_out += decompressed;
+	if (decompressed == 0)
+		*p = NULL;
+	else
+		*p = state->out_block;
+	return (decompressed);
+}
+
+/*
+ * Clean up the decompressor.
+ */
+static int
+lzma_filter_close(struct archive_read_filter *self)
+{
+	struct private_data *state;
+	int ret;
+
+	state = (struct private_data *)self->data;
+	ret = ARCHIVE_OK;
+	switch (lzmadec_end(&(state->stream))) {
+	case LZMADEC_OK:
+		break;
+	default:
+		archive_set_error(&(self->archive->archive),
+		    ARCHIVE_ERRNO_MISC,
+		    "Failed to clean up %s compressor",
+		    self->archive->archive.compression_name);
+		ret = ARCHIVE_FATAL;
+	}
+
+	free(state->out_block);
+	free(state);
+	return (ret);
+}
+
+#else
+
+/*
+ *
+ * If we have no suitable library on this system, we can't actually do
+ * the decompression.  We can, however, still detect compressed
+ * archives and emit a useful message.
+ *
+ */
+static int
+lzma_bidder_init(struct archive_read_filter *self)
+{
+	int r;
+
+	r = __archive_read_program(self, "unlzma");
+	/* Note: We set the format here even if __archive_read_program()
+	 * above fails.  We do, after all, know what the format is
+	 * even if we weren't able to read it. */
+	self->code = ARCHIVE_COMPRESSION_LZMA;
+	self->name = "lzma";
+	return (r);
+}
+
+#endif /* HAVE_LZMADEC_H */
+
+
+static int
+xz_bidder_init(struct archive_read_filter *self)
+{
+	int r;
+
+	r = __archive_read_program(self, "unxz");
+	/* Note: We set the format here even if __archive_read_program()
+	 * above fails.  We do, after all, know what the format is
+	 * even if we weren't able to read it. */
+	self->code = ARCHIVE_COMPRESSION_XZ;
+	self->name = "xz";
+	return (r);
+}
+
+
+#endif /* HAVE_LZMA_H */
diff --git a/lib/libarchive/archive_write_set_compression_xz.c b/lib/libarchive/archive_write_set_compression_xz.c
new file mode 100644
index 0000000..8396252
--- /dev/null
+++ b/lib/libarchive/archive_write_set_compression_xz.c
@@ -0,0 +1,439 @@
+/*-
+ * Copyright (c) 2009 Michihiro NAKAJIMA
+ * 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(S) ``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(S) 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.
+ */
+
+#include "archive_platform.h"
+
+__FBSDID("$FreeBSD$");
+
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#include <time.h>
+#ifdef HAVE_LZMA_H
+#include <lzma.h>
+#endif
+
+#include "archive.h"
+#include "archive_private.h"
+#include "archive_write_private.h"
+
+#ifndef HAVE_LZMA_H
+int
+archive_write_set_compression_xz(struct archive *a)
+{
+	archive_set_error(a, ARCHIVE_ERRNO_MISC,
+	    "xz compression not supported on this platform");
+	return (ARCHIVE_FATAL);
+}
+
+int
+archive_write_set_compression_lzma(struct archive *a)
+{
+	archive_set_error(a, ARCHIVE_ERRNO_MISC,
+	    "lzma compression not supported on this platform");
+	return (ARCHIVE_FATAL);
+}
+#else
+/* Don't compile this if we don't have liblzma. */
+
+struct private_data {
+	lzma_stream	 stream;
+	lzma_filter	 lzmafilters[2];
+	lzma_options_lzma lzma_opt;
+	int64_t		 total_in;
+	unsigned char	*compressed;
+	size_t		 compressed_buffer_size;
+};
+
+struct private_config {
+	int		 compression_level;
+};
+
+static int	archive_compressor_xz_init(struct archive_write *);
+static int	archive_compressor_xz_options(struct archive_write *,
+		    const char *, const char *);
+static int	archive_compressor_xz_finish(struct archive_write *);
+static int	archive_compressor_xz_write(struct archive_write *,
+		    const void *, size_t);
+static int	drive_compressor(struct archive_write *, struct private_data *,
+		    int finishing);
+
+
+/*
+ * Allocate, initialize and return a archive object.
+ */
+int
+archive_write_set_compression_xz(struct archive *_a)
+{
+	struct private_config *config;
+	struct archive_write *a = (struct archive_write *)_a;
+	__archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
+	    ARCHIVE_STATE_NEW, "archive_write_set_compression_xz");
+	config = calloc(1, sizeof(*config));
+	if (config == NULL) {
+		archive_set_error(&a->archive, ENOMEM, "Out of memory");
+		return (ARCHIVE_FATAL);
+	}
+	a->compressor.config = config;
+	a->compressor.finish = archive_compressor_xz_finish;
+	config->compression_level = LZMA_PRESET_DEFAULT;
+	a->compressor.init = &archive_compressor_xz_init;
+	a->compressor.options = &archive_compressor_xz_options;
+	a->archive.compression_code = ARCHIVE_COMPRESSION_XZ;
+	a->archive.compression_name = "xz";
+	return (ARCHIVE_OK);
+}
+
+/* LZMA is handled identically, we just need a different compression
+ * code set.  (The liblzma setup looks at the code to determine
+ * the one place that XZ and LZMA require different handling.) */
+int
+archive_write_set_compression_lzma(struct archive *_a)
+{
+	struct archive_write *a = (struct archive_write *)_a;
+	int r = archive_write_set_compression_xz(_a);
+	if (r != ARCHIVE_OK)
+		return (r);
+	a->archive.compression_code = ARCHIVE_COMPRESSION_LZMA;
+	a->archive.compression_name = "lzma";
+	return (ARCHIVE_OK);
+}
+
+static int
+archive_compressor_xz_init_stream(struct archive_write *a,
+    struct private_data *state)
+{
+	int ret;
+
+	state->stream = (lzma_stream)LZMA_STREAM_INIT;
+	state->stream.next_out = state->compressed;
+	state->stream.avail_out = state->compressed_buffer_size;
+	if (a->archive.compression_code == ARCHIVE_COMPRESSION_XZ)
+		ret = lzma_stream_encoder(&(state->stream),
+		    state->lzmafilters, LZMA_CHECK_CRC64);
+	else
+		ret = lzma_alone_encoder(&(state->stream), &state->lzma_opt);
+	if (ret == LZMA_OK)
+		return (ARCHIVE_OK);
+
+	switch (ret) {
+	case LZMA_MEM_ERROR:
+		archive_set_error(&a->archive, ENOMEM,
+		    "Internal error initializing compression library: "
+		    "Cannot allocate memory");
+		break;
+	default:
+		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
+		    "Internal error initializing compression library: "
+		    "It's a bug in liblzma");
+		break;
+	}
+	return (ARCHIVE_FATAL);
+}
+
+/*
+ * Setup callback.
+ */
+static int
+archive_compressor_xz_init(struct archive_write *a)
+{
+	int ret;
+	struct private_data *state;
+	struct private_config *config;
+
+	if (a->client_opener != NULL) {
+		ret = (a->client_opener)(&a->archive, a->client_data);
+		if (ret != ARCHIVE_OK)
+			return (ret);
+	}
+
+	state = (struct private_data *)malloc(sizeof(*state));
+	if (state == NULL) {
+		archive_set_error(&a->archive, ENOMEM,
+		    "Can't allocate data for compression");
+		return (ARCHIVE_FATAL);
+	}
+	memset(state, 0, sizeof(*state));
+	config = a->compressor.config;
+
+	/*
+	 * See comment above.  We should set compressed_buffer_size to
+	 * max(bytes_per_block, 65536), but the code can't handle that yet.
+	 */
+	state->compressed_buffer_size = a->bytes_per_block;
+	state->compressed = (unsigned char *)malloc(state->compressed_buffer_size);
+	if (state->compressed == NULL) {
+		archive_set_error(&a->archive, ENOMEM,
+		    "Can't allocate data for compression buffer");
+		free(state);
+		return (ARCHIVE_FATAL);
+	}
+	a->compressor.write = archive_compressor_xz_write;
+
+	/* Initialize compression library. */
+	if (lzma_lzma_preset(&state->lzma_opt, config->compression_level)) {
+		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
+		    "Internal error initializing compression library");
+		free(state->compressed);
+		free(state);
+	}
+	state->lzmafilters[0].id = LZMA_FILTER_LZMA2;
+	state->lzmafilters[0].options = &state->lzma_opt;
+	state->lzmafilters[1].id = LZMA_VLI_UNKNOWN;/* Terminate */
+	ret = archive_compressor_xz_init_stream(a, state);
+	if (ret == LZMA_OK) {
+		a->compressor.data = state;
+		return (0);
+	}
+	/* Library setup failed: clean up. */
+	free(state->compressed);
+	free(state);
+
+	return (ARCHIVE_FATAL);
+}
+
+/*
+ * Set write options.
+ */
+static int
+archive_compressor_xz_options(struct archive_write *a, const char *key,
+    const char *value)
+{
+	struct private_config *config;
+
+	config = (struct private_config *)a->compressor.config;
+	if (strcmp(key, "compression-level") == 0) {
+		if (value == NULL || !(value[0] >= '0' && value[0] <= '9') ||
+		    value[1] != '\0')
+			return (ARCHIVE_WARN);
+		config->compression_level = value[0] - '0';
+		if (config->compression_level > 6)
+			config->compression_level = 6;
+		return (ARCHIVE_OK);
+	}
+
+	return (ARCHIVE_WARN);
+}
+
+/*
+ * Write data to the compressed stream.
+ */
+static int
+archive_compressor_xz_write(struct archive_write *a, const void *buff,
+    size_t length)
+{
+	struct private_data *state;
+	int ret;
+
+	state = (struct private_data *)a->compressor.data;
+	if (a->client_writer == NULL) {
+		archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
+		    "No write callback is registered?  "
+		    "This is probably an internal programming error.");
+		return (ARCHIVE_FATAL);
+	}
+
+	/* Update statistics */
+	state->total_in += length;
+
+	/* Compress input data to output buffer */
+	state->stream.next_in = buff;
+	state->stream.avail_in = length;
+	if ((ret = drive_compressor(a, state, 0)) != ARCHIVE_OK)
+		return (ret);
+
+	a->archive.file_position += length;
+	return (ARCHIVE_OK);
+}
+
+
+/*
+ * Finish the compression...
+ */
+static int
+archive_compressor_xz_finish(struct archive_write *a)
+{
+	ssize_t block_length, target_block_length, bytes_written;
+	int ret;
+	struct private_data *state;
+	unsigned tocopy;
+
+	ret = ARCHIVE_OK;
+	state = (struct private_data *)a->compressor.data;
+	if (state != NULL) {
+		if (a->client_writer == NULL) {
+			archive_set_error(&a->archive,
+			    ARCHIVE_ERRNO_PROGRAMMER,
+			    "No write callback is registered?  "
+			    "This is probably an internal programming error.");
+			ret = ARCHIVE_FATAL;
+			goto cleanup;
+		}
+
+		/* By default, always pad the uncompressed data. */
+		if (a->pad_uncompressed) {
+			tocopy = a->bytes_per_block -
+			    (state->total_in % a->bytes_per_block);
+			while (tocopy > 0 && tocopy < (unsigned)a->bytes_per_block) {
+				state->stream.next_in = a->nulls;
+				state->stream.avail_in = tocopy < a->null_length ?
+				    tocopy : a->null_length;
+				state->total_in += state->stream.avail_in;
+				tocopy -= state->stream.avail_in;
+				ret = drive_compressor(a, state, 0);
+				if (ret != ARCHIVE_OK)
+					goto cleanup;
+			}
+		}
+
+		/* Finish compression cycle */
+		if (((ret = drive_compressor(a, state, 1))) != ARCHIVE_OK)
+			goto cleanup;
+
+		/* Optionally, pad the final compressed block. */
+		block_length = state->stream.next_out - state->compressed;
+
+		/* Tricky calculation to determine size of last block. */
+		target_block_length = block_length;
+		if (a->bytes_in_last_block <= 0)
+			/* Default or Zero: pad to full block */
+			target_block_length = a->bytes_per_block;
+		else
+			/* Round length to next multiple of bytes_in_last_block. */
+			target_block_length = a->bytes_in_last_block *
+			    ( (block_length + a->bytes_in_last_block - 1) /
+				a->bytes_in_last_block);
+		if (target_block_length > a->bytes_per_block)
+			target_block_length = a->bytes_per_block;
+		if (block_length < target_block_length) {
+			memset(state->stream.next_out, 0,
+			    target_block_length - block_length);
+			block_length = target_block_length;
+		}
+
+		/* Write the last block */
+		bytes_written = (a->client_writer)(&a->archive, a->client_data,
+		    state->compressed, block_length);
+		if (bytes_written <= 0) {
+			ret = ARCHIVE_FATAL;
+			goto cleanup;
+		}
+		a->archive.raw_position += bytes_written;
+
+		/* Cleanup: shut down compressor, release memory, etc. */
+	cleanup:
+		lzma_end(&(state->stream));
+		free(state->compressed);
+		free(state);
+	}
+	free(a->compressor.config);
+	a->compressor.config = NULL;
+	return (ret);
+}
+
+/*
+ * Utility function to push input data through compressor,
+ * writing full output blocks as necessary.
+ *
+ * Note that this handles both the regular write case (finishing ==
+ * false) and the end-of-archive case (finishing == true).
+ */
+static int
+drive_compressor(struct archive_write *a, struct private_data *state, int finishing)
+{
+	ssize_t bytes_written;
+	int ret;
+
+	for (;;) {
+		if (state->stream.avail_out == 0) {
+			bytes_written = (a->client_writer)(&a->archive,
+			    a->client_data, state->compressed,
+			    state->compressed_buffer_size);
+			if (bytes_written <= 0) {
+				/* TODO: Handle this write failure */
+				return (ARCHIVE_FATAL);
+			} else if ((size_t)bytes_written < state->compressed_buffer_size) {
+				/* Short write: Move remaining to
+				 * front of block and keep filling */
+				memmove(state->compressed,
+				    state->compressed + bytes_written,
+				    state->compressed_buffer_size - bytes_written);
+			}
+			a->archive.raw_position += bytes_written;
+			state->stream.next_out
+			    = state->compressed +
+			    state->compressed_buffer_size - bytes_written;
+			state->stream.avail_out = bytes_written;
+		}
+
+		/* If there's nothing to do, we're done. */
+		if (!finishing && state->stream.avail_in == 0)
+			return (ARCHIVE_OK);
+
+		ret = lzma_code(&(state->stream),
+		    finishing ? LZMA_FINISH : LZMA_RUN );
+
+		switch (ret) {
+		case LZMA_OK:
+			/* In non-finishing case, check if compressor
+			 * consumed everything */
+			if (!finishing && state->stream.avail_in == 0)
+				return (ARCHIVE_OK);
+			/* In finishing case, this return always means
+			 * there's more work */
+			break;
+		case LZMA_STREAM_END:
+			/* This return can only occur in finishing case. */
+			if (finishing)
+				return (ARCHIVE_OK);
+			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
+			    "lzma compression data error");
+			return (ARCHIVE_FATAL);
+		case LZMA_MEMLIMIT_ERROR:
+			archive_set_error(&a->archive, ENOMEM,
+			    "lzma compression error: "
+			    "%ju MiB would have been needed",
+			    (lzma_memusage(&(state->stream)) + 1024 * 1024 -1)
+			    / (1024 * 1024));
+			return (ARCHIVE_FATAL);
+		default:
+			/* Any other return value indicates an error. */
+			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
+			    "lzma compression failed:"
+			    " lzma_code() call returned status %d",
+			    ret);
+			return (ARCHIVE_FATAL);
+		}
+	}
+}
+
+#endif /* HAVE_LZMA_H */