zlib.c File Reference

zlib compressed images More...

#include <stdlib.h>
#include <errno.h>
#include <assert.h>
#include <ipxe/deflate.h>
#include <ipxe/image.h>
#include <ipxe/zlib.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
int	zlib_deflate (enum deflate_format format, const void *data, size_t len, struct image *extracted)
	Extract compressed data to image. More...
static int	zlib_extract (struct image *image, struct image *extracted)
	Extract zlib image. More...
static int	zlib_probe (struct image *image)
	Probe zlib image. More...
struct image_type zlib_image_type	__image_type (PROBE_NORMAL)
	zlib image type More...

Detailed Description

zlib compressed images

Definition in file zlib.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

zlib_deflate()

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

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 48 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().

zlib_extract()

static int zlib_extract ( struct image *  image, struct image *  extracted  )

static

Extract zlib image.

Parameters

image	Image
extracted	Extracted image

Return values

rc	Return status code

Definition at line 117 of file zlib.c.

                                                                         {
        int rc;

        /* Decompress image */
        if ( ( rc = zlib_deflate ( DEFLATE_ZLIB, image->data, image->len,
                                   extracted ) ) != 0 )
                return rc;

        return 0;
}

References image::data, DEFLATE_ZLIB, image::len, rc, and zlib_deflate().

zlib_probe()

static int zlib_probe ( struct image *  image )

static

Probe zlib image.

Parameters

image

zlib image

Return values

rc	Return status code

Definition at line 134 of file zlib.c.

                                              {
        const union zlib_magic *magic;

        /* Sanity check */
        if ( image->len < sizeof ( *magic ) ) {
                DBGC ( image, "ZLIB %s image too short\n", image->name );
                return -ENOEXEC;
        }
        magic = image->data;

        /* Check magic header */
        if ( ! zlib_magic_is_valid ( magic ) ) {
                DBGC ( image, "ZLIB %s invalid magic data\n", image->name );
                return -ENOEXEC;
        }

        return 0;
}

References image::data, DBGC, ENOEXEC, image::len, magic, image::name, and zlib_magic_is_valid().

__image_type()

struct image_type zlib_image_type __image_type

(

PROBE_NORMAL

)

zlib image type