gzip.h

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#ifndef _IPXE_GZIP_H
#define _IPXE_GZIP_H
 
/** @file
 *
 * gzip compressed images
 *
 */
 
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
FILE_SECBOOT ( PERMITTED );
 
#include <stdint.h>
#include <ipxe/image.h>
 
/** gzip header */
struct gzip_header {
        /** Magic ID */
        uint16_t magic;
        /** Compression method */
        uint8_t method;
        /** Flags */
        uint8_t flags;
        /** Modification time */
        uint32_t mtime;
        /** Extra flags */
        uint8_t extra;
        /** Operating system */
        uint8_t os;
} __attribute__ (( packed ));
 
/** Magic ID */
#define GZIP_MAGIC 0x1f8b
 
/** Compression method */
#define GZIP_METHOD_DEFLATE 0x08
 
/** CRC header is present */
#define GZIP_FL_HCRC 0x02
 
/** Extra header is present */
#define GZIP_FL_EXTRA 0x04
 
/** File name is present */
#define GZIP_FL_NAME 0x08
 
/** File comment is present */
#define GZIP_FL_COMMENT 0x10
 
/** gzip extra header */
struct gzip_extra_header {
        /** Extra header length (excluding this field) */
        uint16_t len;
} __attribute__ (( packed ));
 
/** gzip CRC header */
struct gzip_crc_header {
        /** CRC-16 */
        uint16_t crc;
} __attribute__ (( packed ));
 
/** gzip footer */
struct gzip_footer {
        /** CRC-32 */
        uint32_t crc;
        /** Uncompressed size (modulo 2^32) */
        uint32_t len;
} __attribute__ (( packed ));
 
extern struct image_type gzip_image_type __image_type ( PROBE_NORMAL );
 
#endif /* _IPXE_GZIP_H */