x86/dom0: support bzip2 and lzma compressed bzImage payloads

This matches functionality in the tools already supporting the same
for DomU-s.

Code taken from Linux 2.6.32-rc and adjusted as little as possible to
be usable in Xen.

The question is whether, particularly for non-Linux Dom0-s, plain ELF
images compressed by bzip2 or lzma should also be supported.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/xen/common/decompress.c b/xen/common/decompress.c
new file mode 100644
index 0000000000..de9950c3a7
--- /dev/null
+++ b/xen/common/decompress.c
@@ -0,0 +1,27 @@
+#include <xen/config.h>
+#include <xen/init.h>
+#include <xen/lib.h>
+#include <xen/string.h>
+#include <xen/decompress.h>
+
+static void __init error(const char *msg)
+{
+    printk("%s\n", msg);
+}
+
+int __init decompress(void *inbuf, unsigned int len, void *outbuf)
+{
+#if 0 /* Not needed here yet. */
+    if ( len >= 2 &&
+         (!memcmp(inbuf, "\037\213", 2) || !memcmp(inbuf, "\037\236", 2)) )
+        return gunzip(inbuf, len, NULL, NULL, outbuf, NULL, error);
+#endif
+
+    if ( len >= 3 && !memcmp(inbuf, "\x42\x5a\x68", 3) )
+        return bunzip2(inbuf, len, NULL, NULL, outbuf, NULL, error);
+
+    if ( len >= 2 && !memcmp(inbuf, "\135\000", 2) )
+        return unlzma(inbuf, len, NULL, NULL, outbuf, NULL, error);
+
+    return 1;
+}