Improve extended attribute support

Mac OS X changes:
  - add support for extended file attributes via sys/xattr.h
  - when extracting an archive entry that has mac_metadata and
    mac_metadata is requested to be extracted, extended attributes
    are restored only from mac_metadata.
  - by default, extended attributes are stored both in mac_metadata and
    SCHILY.xattr/LIBARCHIVE.xattr. This is subject to review and change.

To match behavior on other platforms, store extended attributes on
FreeBSD with extattr_set_link() if no fd is provided.

Detection of extended attributes support in configure stage has been
rewritten.

Added xattr platform test to libarchive and xattrs option test to bsdtar.

2 files changed, 95 insertions, 0 deletions

diff --git a/test_utils/test_common.h b/test_utils/test_common.h
index eca7b363..fa726bff 100644
--- a/test_utils/test_common.h
+++ b/test_utils/test_common.h
@@ -134,6 +134,7 @@
 #define	ARCHIVE_TEST_ACL_TYPE_POSIX1E	1
 #define	ARCHIVE_TEST_ACL_TYPE_NFS4	2
 
+#include "archive_platform_xattr.h"
 
 /*
  * Redefine DEFINE_TEST for use in defining the test functions.
@@ -346,6 +347,12 @@ int canNodump(void);
 /* Set test ACLs */
 int setTestAcl(const char *path);
 
+/* Get extended attribute */
+const void *getXattr(const char *, const char *, size_t *);
+
+/* Set extended attribute */
+int setXattr(const char *, const char *, const void *, size_t);
+
 /* Return true if the file has large i-node number(>0xffffffff). */
 int is_LargeInode(const char *);
 
diff --git a/test_utils/test_main.c b/test_utils/test_main.c
index 0ef6d6fc..36dfc82f 100644
--- a/test_utils/test_main.c
+++ b/test_utils/test_main.c
@@ -67,6 +67,17 @@
 #ifdef HAVE_SYS_ACL_H
 #include <sys/acl.h>
 #endif
+#ifdef HAVE_SYS_EA_H
+#include <sys/ea.h>
+#endif
+#ifdef HAVE_SYS_EXTATTR_H
+#include <sys/extattr.h>
+#endif
+#if HAVE_SYS_XATTR_H
+#include <sys/xattr.h>
+#elif HAVE_ATTR_XATTR_H
+#include <attr/xattr.h>
+#endif
 #ifdef HAVE_SYS_RICHACL_H
 #include <sys/richacl.h>
 #endif
@@ -2440,6 +2451,83 @@ canNodump(void)
 	return (0);
 }
 
+/* Get extended attribute from a path */
+const void *
+getXattr(const char *path, const char *name, size_t *sizep)
+{ 
+	void *value = NULL;
+#if ARCHIVE_XATTR_SUPPORT
+	ssize_t size;
+#if ARCHIVE_XATTR_LINUX
+	size = lgetxattr(path, name, NULL, 0);
+#elif ARCHIVE_XATTR_DARWIN
+	size = getxattr(path, name, NULL, 0, 0, XATTR_NOFOLLOW);
+#elif ARCHIVE_XATTR_AIX
+	size = lgetea(path, name, NULL, 0);
+#elif ARCHIVE_XATTR_FREEBSD
+	size = extattr_get_link(path, EXTATTR_NAMESPACE_USER, name + 5,
+	    NULL, 0);
+#endif
+
+	if (size >= 0) {
+		value = malloc(size);
+#if ARCHIVE_XATTR_LINUX
+		size = lgetxattr(path, name, value, size);
+#elif ARCHIVE_XATTR_DARWIN
+		size = getxattr(path, name, value, size, 0, XATTR_NOFOLLOW);
+#elif ARCHIVE_XATTR_AIX
+		size = lgetea(path, name, value, size);
+#elif ARCHIVE_XATTR_FREEBSD
+		size = extattr_get_link(path, EXTATTR_NAMESPACE_USER, name + 5,
+		    value, size);
+#endif
+		if (size < 0) {
+			free(value);
+			value = NULL;
+		}
+	}
+	if (size < 0)
+		*sizep = 0;
+	else
+		*sizep = (size_t)size;
+#else	/* !ARCHIVE_XATTR_SUPPORT */
+	(void)path;	/* UNUSED */
+	(void)name;	/* UNUSED */
+	*sizep = 0;
+#endif 	/* !ARCHIVE_XATTR_SUPPORT */
+	return (value);
+}
+
+/*
+ * Set extended attribute on a path
+ * Returns 0 on error, 1 on success
+ */
+int
+setXattr(const char *path, const char *name, const void *value, size_t size)
+{
+#if ARCHIVE_XATTR_SUPPORT
+#if ARCHIVE_XATTR_LINUX
+	if (lsetxattr(path, name, value, size, 0) == 0)
+#elif ARCHIVE_XATTR_DARWIN
+	if (setxattr(path, name, value, size, 0, XATTR_NOFOLLOW) == 0)
+#elif ARCHIVE_XATTR_AIX
+	if (lsetea(path, name, value, size, 0) == 0)
+#elif ARCHIVE_XATTR_FREEBSD
+	if (extattr_set_link(path, EXTATTR_NAMESPACE_USER, name + 5, value,
+	    size) > -1)
+#else
+	if (0)
+#endif
+		return (1);
+#else	/* !ARCHIVE_XATTR_SUPPORT */
+	(void)path;     /* UNUSED */
+	(void)name;	/* UNUSED */
+	(void)value;	/* UNUSED */
+	(void)size;	/* UNUSED */
+#endif	/* !ARCHIVE_XATTR_SUPPORT */
+	return (0);
+}
+
 #if ARCHIVE_ACL_SUNOS
 /* Fetch ACLs on Solaris using acl() or facl() */
 void *