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, 102 insertions, 0 deletions

diff --git a/lib/libarchive/archive_check_magic.c b/lib/libarchive/archive_check_magic.c
new file mode 100644
index 0000000..719ba9e
--- /dev/null
+++ b/lib/libarchive/archive_check_magic.c
@@ -0,0 +1,102 @@
+/*-
+ * 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 <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "archive_private.h"
+
+static void
+diediedie(void)
+{
+	*(char *)0 = 1;	/* Deliberately segfault and force a coredump. */
+	_exit(1);	/* If that didn't work, just exit with an error. */
+}
+
+static const char *
+state_name(unsigned s)
+{
+	switch (s) {
+	case ARCHIVE_STATE_NEW:		return ("new");
+	case ARCHIVE_STATE_HEADER:	return ("header");
+	case ARCHIVE_STATE_DATA:	return ("data");
+	case ARCHIVE_STATE_EOF:		return ("eof");
+	case ARCHIVE_STATE_CLOSED:	return ("closed");
+	case ARCHIVE_STATE_FATAL:	return ("fatal");
+	default:			return ("??");
+	}
+}
+
+
+static void
+write_all_states(FILE *f, int states)
+{
+	unsigned lowbit;
+
+	/* A trick for computing the lowest set bit. */
+	while ((lowbit = states & (-states)) != 0) {
+		states &= ~lowbit;		/* Clear the low bit. */
+		fprintf(f, "%s%s", state_name(lowbit),
+		    (states != 0) ? "/" : "");
+	}
+}
+
+/*
+ * Check magic value and current state; bail if it isn't valid.
+ *
+ * This is designed to catch serious programming errors that violate
+ * the libarchive API.
+ */
+void
+__archive_check_magic(struct archive *a, unsigned magic, unsigned state,
+    const char *function)
+{
+	if (a->magic != magic) {
+		fprintf(stderr, "INTERNAL ERROR: Function %s invoked"
+		    " with invalid struct archive structure.\n", function);
+		diediedie();
+	}
+
+	if (state == ARCHIVE_STATE_ANY)
+		return;
+
+	if ((a->state & state) == 0) {
+		fprintf(stderr, "INTERNAL ERROR: Function '%s' invoked"
+		    " with archive structure in state '", function);
+		write_all_states(stderr, a->state);
+		fprintf(stderr,"', should be in state '");
+		write_all_states(stderr, state);
+		fprintf(stderr, "'\n");
+		diediedie();
+	}
+}