Initial import of libarchive.

What it is:
   A library for reading and writing various streaming archive
   formats, especially tar and cpio.  Being a library, it should
   be easy to incorporate into pkg_* tools, sysinstall, and any
   other place that needs to read or write such archives.

Features:
  * Full automatic detection of both compression and archive format.
  * Extensible internal architecture to make it easy to add new formats.
  * Support for "pax interchange format," a new POSIX-standard tar format
    that eliminates essentially all of the restrictions of historic formats.
  * BSD license

Thanks to: jkh for pushing me to start this work, gordon for
  encouraging me to commit it, bde for answering endless style
  questions, and many others for feedback and encouragement.

Status: Pretty good overall, though there are still a few rough edges and
  the library could always use more testing.  Feedback eagerly solicited.

1 files changed, 259 insertions, 0 deletions

diff --git a/lib/libarchive/archive_read_support_compression_none.c b/lib/libarchive/archive_read_support_compression_none.c
new file mode 100644
index 0000000..0f7e42f
--- /dev/null
+++ b/lib/libarchive/archive_read_support_compression_none.c
@@ -0,0 +1,259 @@
+/*-
+ * Copyright (c) 2003-2004 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
+ *    in this position and unchanged.
+ * 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 <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#ifdef DMALLOC
+#include <dmalloc.h>
+#endif
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "archive.h"
+#include "archive_private.h"
+
+struct archive_decompress_none {
+	char		*buffer;
+	size_t		 buffer_size;
+	char		*next;		/* Current read location. */
+	size_t		 avail;		/* Bytes in my buffer. */
+	const char	*client_buff;	/* Client buffer information. */
+	size_t		 client_total;
+	const char	*client_next;
+	size_t		 client_avail;
+	char		 end_of_file;
+	char		 fatal;
+};
+
+/*
+ * Size of internal buffer used for combining short reads.  This is
+ * also an upper limit on the size of a read request.  Recall,
+ * however, that we can (and will!) return blocks of data larger than
+ * this.  The read semantics are: you ask for a minimum, I give you a
+ * pointer to my best-effort match and tell you how much data is
+ * there.  It could be less than you asked for, it could be much more.
+ * For example, a client might use mmap() to "read" the entire file as
+ * a single block.  In that case, I will return that entire block to
+ * my clients.
+ */
+#define	BUFFER_SIZE	65536
+
+static int	archive_decompressor_none_bid(const void *, size_t);
+static int	archive_decompressor_none_finish(struct archive *);
+static int	archive_decompressor_none_init(struct archive *,
+		    const void *, size_t);
+static ssize_t	archive_decompressor_none_read_ahead(struct archive *,
+		    const void **, size_t);
+static ssize_t	archive_decompressor_none_read_consume(struct archive *,
+		    size_t);
+
+int
+archive_read_support_compression_none(struct archive *a)
+{
+	return (__archive_read_register_compression(a,
+		    archive_decompressor_none_bid,
+		    archive_decompressor_none_init));
+}
+
+/*
+ * Try to detect an "uncompressed" archive.
+ */
+static int
+archive_decompressor_none_bid(const void *buff, size_t len)
+{
+	(void)buff;
+	(void)len;
+
+	return (1); /* Default: We'll take it if noone else does. */
+}
+
+static int
+archive_decompressor_none_init(struct archive *a, const void *buff, size_t n)
+{
+	struct archive_decompress_none	*state;
+
+	a->compression_code = ARCHIVE_COMPRESSION_NONE;
+	a->compression_name = "none";
+
+	state = (struct archive_decompress_none *)malloc(sizeof(*state));
+	if (!state) {
+		archive_set_error(a, ENOMEM, "Can't allocate input data");
+		return (ARCHIVE_FATAL);
+	}
+	memset(state, 0, sizeof(*state));
+
+	state->buffer_size = BUFFER_SIZE;
+	state->buffer = malloc(state->buffer_size);
+	state->next = state->buffer;
+	if (state->buffer == NULL) {
+		free(state);
+		archive_set_error(a, ENOMEM, "Can't allocate input buffer");
+		return (ARCHIVE_FATAL);
+	}
+
+	/* Save reference to first block of data. */
+	state->client_buff = buff;
+	state->client_total = n;
+	state->client_next = state->client_buff;
+	state->client_avail = state->client_total;
+
+	a->compression_data = state;
+	a->compression_read_ahead = archive_decompressor_none_read_ahead;
+	a->compression_read_consume = archive_decompressor_none_read_consume;
+	a->compression_finish = archive_decompressor_none_finish;
+
+	return (ARCHIVE_OK);
+}
+
+/*
+ * We just pass through pointers to the client buffer if we can.
+ * If the client buffer is short, then we copy stuff to our internal
+ * buffer to combine reads.
+ */
+static ssize_t
+archive_decompressor_none_read_ahead(struct archive *a, const void **buff,
+    size_t min)
+{
+	struct archive_decompress_none *state;
+	ssize_t bytes_read;
+
+	state = a->compression_data;
+	if (state->fatal)
+		return (-1);
+
+	if (min > state->buffer_size)
+		min = state->buffer_size;
+
+	/* Keep reading until we have accumulated enough data. */
+	while (state->avail + state->client_avail < min) {
+		if (state->next > state->buffer &&
+		    state->next + min > state->buffer + state->buffer_size &&
+		    state->avail > 0) {
+			memmove(state->buffer, state->next, state->avail);
+			state->next = state->buffer;
+		}
+		if (state->client_avail > 0) {
+			memcpy(state->next + state->avail, state->client_next,
+			     state->client_avail);
+			state->client_next += state->client_avail;
+			state->avail += state->client_avail;
+			state->client_avail = 0;
+		}
+		/*
+		 * It seems to me that const void ** and const char **
+		 * should be compatible, but they aren't, hence the cast.
+		 */
+		bytes_read = (a->client_reader)(a, a->client_data,
+		    (const void **)&state->client_buff);
+		if (bytes_read < 0) {		/* Read error. */
+			state->client_total = state->client_avail = 0;
+			state->client_next = state->client_buff = NULL;
+			state->fatal = 1;
+			return (-1);
+		}
+		if (bytes_read == 0) {		/* End-of-file. */
+			state->client_total = state->client_avail = 0;
+			state->client_next = state->client_buff = NULL;
+			state->end_of_file = 1;
+			break;
+		}
+		state->client_total = bytes_read;
+		state->client_avail = state->client_total;
+		state->client_next = state->client_buff;
+	}
+
+	/* Common case: If client buffer suffices, use that. */
+	if (state->avail == 0) {
+		*buff = state->client_next;
+		return (state->client_avail);
+	}
+
+	/* Add in bytes from client buffer as necessary to meet the minimum. */
+	if (min > state->avail + state->client_avail)
+		min = state->avail + state->client_avail;
+	if (state->avail < min) {
+		memcpy(state->next + state->avail, state->client_next,
+		     min - state->avail);
+		state->client_next += min - state->avail;
+		state->client_avail -= min - state->avail;
+		state->avail = min;
+	}
+
+	*buff = state->next;
+	return (state->avail);
+}
+
+/*
+ * Mark the appropriate data as used.  Note that the request here could
+ * be much smaller than the size of the previous read_ahead request, but
+ * typically it won't be.  I make an attempt to go back to reading straight
+ * from the client buffer in case some end-of-block alignment mismatch forced
+ * me to combine writes above.
+ */
+static ssize_t
+archive_decompressor_none_read_consume(struct archive *a, size_t request)
+{
+	struct archive_decompress_none *state;
+
+	state = a->compression_data;
+	if (state->avail > 0) {
+		state->next += request;
+		state->avail -= request;
+		/*
+		 * Rollback state->client_next if we can so that future
+		 * reads come straight from the client buffer and we
+		 * avoid copying more data into our buffer.
+		 */
+		if (state->avail <=
+		    (size_t)(state->client_next - state->client_buff)) {
+			state->client_next -= state->avail;
+			state->client_avail += state->avail;
+			state->avail = 0;
+			state->next = state->buffer;
+		}
+	} else {
+		state->client_next += request;
+		state->client_avail -= request;
+	}
+	return (request);
+}
+
+static int
+archive_decompressor_none_finish(struct archive *a)
+{
+	struct archive_decompress_none	*state;
+
+	state = a->compression_data;
+	free(state->buffer);
+	free(state);
+	a->compression_data = NULL;
+	if (a->client_closer != NULL)
+		return ((a->client_closer)(a, a->client_data));
+	return (ARCHIVE_OK);
+}