zlib.h File Reference

zlib compressed images More...

#include <stdint.h>
#include <byteswap.h>
#include <ipxe/image.h>
#include <ipxe/deflate.h>

Go to the source code of this file.

Data Structures
union	zlib_magic
	zlib magic header More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
	FILE_SECBOOT (PERMITTED)
static int	zlib_magic_is_valid (const union zlib_magic *magic)
	Check that zlib magic header is valid.
int	zlib_deflate (enum deflate_format format, const void *data, size_t len, struct image *extracted)
	Extract compressed data to image.
struct image_type zlib_image_type	__image_type (PROBE_NORMAL)

Detailed Description

zlib compressed images

Definition in file zlib.h.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

FILE_SECBOOT()

FILE_SECBOOT

(

PERMITTED

)

zlib_magic_is_valid()

int zlib_magic_is_valid ( const union zlib_magic * magic )

inlinestatic

Check that zlib magic header is valid.

Parameters

magic

Magic header

Return values

is_valid

Magic header is valid

Definition at line 32 of file zlib.h.

                                                                        {
 
        /* Check magic value as per RFC 6713 */
        return ( ( ( magic->cmf & 0x8f ) == 0x08 ) &&
                 ( ( be16_to_cpu ( magic->check ) % 31 ) == 0 ) );
}

References be16_to_cpu, and magic.

Referenced by zlib_probe().

zlib_deflate()

int zlib_deflate ( enum deflate_format format, const void * data, size_t len, struct image * extracted )

extern

Extract compressed data to image.

Parameters

format	Compression format code
data	Compressed input data
len	Length of compressed input data
extracted	Extracted image

Return values

rc	Return status code

Definition at line 49 of file zlib.c.

                                             {
        struct deflate *deflate;
        struct deflate_chunk out;
        int rc;
 
        /* Allocate and initialise decompressor */
        deflate = zalloc ( sizeof ( *deflate ) );
        if ( ! deflate ) {
                rc = -ENOMEM;
                goto err_alloc;
        }
 
        /* Decompress data, (re)allocating if necessary */
        while ( 1 ) {
 
                /* (Re)initialise decompressor */
                deflate_init ( deflate, format );
 
                /* Initialise output chunk */
                deflate_chunk_init ( &out, extracted->rwdata, 0,
                                     extracted->len );
 
                /* Decompress data */
                if ( ( rc = deflate_inflate ( deflate, data, len,
                                              &out ) ) != 0 ) {
                        DBGC ( extracted, "ZLIB %s could not decompress: %s\n",
                               extracted->name, strerror ( rc ) );
                        goto err_inflate;
                }
 
                /* Check that decompression is valid */
                if ( ! deflate_finished ( deflate ) ) {
                        DBGC ( extracted, "ZLIB %s decompression incomplete\n",
                               extracted->name );
                        rc = -EINVAL;
                        goto err_unfinished;
                }
 
                /* Finish if output image size was correct */
                if ( out.offset == extracted->len )
                        break;
 
                /* Otherwise, resize output image and retry */
                if ( ( rc = image_set_len ( extracted, out.offset ) ) != 0 ) {
                        DBGC ( extracted, "ZLIB %s could not resize: %s\n",
                               extracted->name, strerror ( rc ) );
                        goto err_set_size;
                }
        }
 
        /* Success */
        rc = 0;
 
 err_set_size:
 err_unfinished:
 err_inflate:
        free ( deflate );
 err_alloc:
        return rc;
}

References data, DBGC, deflate_finished(), deflate_inflate(), deflate_init(), EINVAL, ENOMEM, format, free, image_set_len(), image::len, len, image::name, out, rc, image::rwdata, strerror(), and zalloc().

Referenced by gzip_extract(), and zlib_extract().

__image_type()

struct image_type zlib_image_type __image_type ( PROBE_NORMAL )

extern

References __image_type, and PROBE_NORMAL.