Imported Debian patch 3.6-1

[debian/elilo] / gzip.h

diff --git a/gzip.h b/gzip.h
new file mode 100644 (file)
index 0000000..88b53f6
--- /dev/null
+++ b/gzip.h
@@ -0,0 +1,67 @@
+/*
+ *  Copyright (C) 2001-2003 Hewlett-Packard Co.
+ *     Contributed by Stephane Eranian <eranian@hpl.hp.com>
+ *
+ * This file is part of the ELILO, the EFI Linux boot loader.
+ *
+ *  ELILO is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2, or (at your option)
+ *  any later version.
+ *
+ *  ELILO is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with ELILO; see the file COPYING.  If not, write to the Free
+ *  Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+ *  02111-1307, USA.
+ *
+ * Please check out the elilo.txt for complete documentation on how
+ * to use this program.
+ */
+
+#ifndef __GZIP_H__
+#define __GZIP_H__
+
+int gunzip_image(memdesc_t *);
+int gunzip_kernel(fops_fd_t, kdesc_t *);
+
+/* gzip flag byte */
+#define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
+#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
+#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
+#define COMMENT      0x10 /* bit 4 set: file comment present */
+#define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
+#define RESERVED     0xC0 /* bit 6,7:   reserved */
+
+/*
+ * check for valid gzip signature
+ * return:
+ *      0 : valid gzip archive
+ *      -1: invalid gzip archive
+ */
+static inline int
+gzip_probe(unsigned char *buf, unsigned long size)
+{
+    if (size < 4) return -1;
+
+    if (buf[0] != 037 ||
+        ((buf[1] != 0213) && (buf[1] != 0236))) return -1;
+
+    /* We only support method #8, DEFLATED */
+    if (buf[2] != 8) return -1;
+    
+    if ((buf[3] & ENCRYPTED) != 0) return -1;
+
+    if ((buf[3] & CONTINUATION) != 0) return -1;
+
+    if ((buf[3] & RESERVED) != 0) return -1;
+
+    return 0;
+}
+
+#endif /* __GZIP_H__ */