cpio.h File Reference

CPIO archives. More...

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

Go to the source code of this file.

Data Structures
struct	cpio_header
	A CPIO archive header. More...

Macros
#define	CPIO_MAGIC   "070701"
	CPIO magic. More...
#define	CPIO_MODE_FILE   0100000
	CPIO type for regular files. More...
#define	CPIO_MODE_DIR   0040000
	CPIO type for directories. More...
#define	CPIO_ALIGN   4
	CPIO header length alignment. More...
#define	INITRD_ALIGN   4096
	Alignment for CPIO archives within an initrd. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
static const char *	cpio_name (struct image *image)
	Get CPIO image name. More...
static size_t	cpio_pad_len (size_t len)
	Get CPIO header zero-padding length. More...
size_t	cpio_header (struct image *image, unsigned int index, struct cpio_header *cpio)
	Construct CPIO header for image, if applicable. More...

Detailed Description

CPIO archives.

Definition in file cpio.h.

Macro Definition Documentation

CPIO_MAGIC

#define CPIO_MAGIC   "070701"

CPIO magic.

Definition at line 52 of file cpio.h.

CPIO_MODE_FILE

#define CPIO_MODE_FILE   0100000

CPIO type for regular files.

Definition at line 55 of file cpio.h.

CPIO_MODE_DIR

#define CPIO_MODE_DIR   0040000

CPIO type for directories.

Definition at line 58 of file cpio.h.

CPIO_ALIGN

#define CPIO_ALIGN   4

CPIO header length alignment.

Definition at line 61 of file cpio.h.

INITRD_ALIGN

#define INITRD_ALIGN   4096

Alignment for CPIO archives within an initrd.

Definition at line 64 of file cpio.h.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

cpio_name()

static const char* cpio_name ( struct image *  image )

inlinestatic

Get CPIO image name.

Parameters

image

Image

Return values

name	Image name (not NUL terminated)

Definition at line 73 of file cpio.h.

                                  {
        return image->cmdline;
}

References image::cmdline.

Referenced by bzimage_load_initrd(), cpio_header(), cpio_max(), cpio_name_len(), and efi_file_read_initrd().

cpio_pad_len()

static size_t cpio_pad_len ( size_t  len )

inlinestatic

Get CPIO header zero-padding length.

Parameters

len	Length of CPIO header (including name, excluding NUL)

Return values

pad_len

Padding length

Definition at line 84 of file cpio.h.

                            {

        /* Pad by at least one byte (for name's terminating NUL) */
        return ( CPIO_ALIGN - ( len % CPIO_ALIGN ) );
}

References CPIO_ALIGN, and len.

Referenced by bzimage_load_initrd(), and efi_file_read_initrd().

cpio_header()

size_t cpio_header	(	struct image *	image,
		unsigned int	index,
		struct cpio_header *	cpio
	)

Construct CPIO header for image, if applicable.

Parameters

image	Image
index	CPIO header index
cpio	CPIO header to fill in

Return values

len	Length of CPIO header (including name, excluding NUL)

Definition at line 151 of file cpio.c.

                                                {
        const char *name = cpio_name ( image );
        unsigned int mode;
        unsigned int count;
        unsigned int max;
        unsigned int depth;
        unsigned int i;
        size_t name_len;
        size_t len;

        /* Parse command line arguments */
        cpio_parse_cmdline ( image, &mode, &count );

        /* Determine number of CPIO headers to be constructed */
        max = cpio_max ( image );
        if ( count > max )
                count = max;

        /* Determine path depth of this CPIO header */
        if ( index >= count )
                return 0;
        depth = ( max - count + index + 1 );

        /* Get filename length */
        name_len = cpio_name_len ( image, depth );

        /* Calculate mode and length */
        if ( depth < max ) {
                /* Directory */
                mode = ( CPIO_MODE_DIR | CPIO_DEFAULT_DIR_MODE );
                len = 0;
        } else {
                /* File */
                mode |= CPIO_MODE_FILE;
                len = image->len;
        }

        /* Construct CPIO header */
        memset ( cpio, '0', sizeof ( *cpio ) );
        memcpy ( cpio->c_magic, CPIO_MAGIC, sizeof ( cpio->c_magic ) );
        cpio_set_field ( cpio->c_mode, mode );
        cpio_set_field ( cpio->c_nlink, 1 );
        cpio_set_field ( cpio->c_filesize, len );
        cpio_set_field ( cpio->c_namesize, ( name_len + 1 /* NUL */ ) );
        DBGC ( image, "CPIO %s %d/%d \"", image->name, depth, max );
        for ( i = 0 ; i < name_len ; i++ )
                DBGC ( image, "%c", name[i] );
        DBGC ( image, "\"\n" );
        DBGC2_HDA ( image, 0, cpio, sizeof ( *cpio ) );

        /* Calculate total length */
        return ( sizeof ( *cpio ) + name_len );
}

References cpio_header::c_filesize, cpio_header::c_magic, cpio_header::c_mode, cpio_header::c_namesize, cpio_header::c_nlink, count, CPIO_DEFAULT_DIR_MODE, CPIO_MAGIC, cpio_max(), CPIO_MODE_DIR, CPIO_MODE_FILE, cpio_name(), cpio_name_len(), cpio_parse_cmdline(), cpio_set_field(), DBGC, DBGC2_HDA, index, len, image::len, max, memcpy(), memset(), image::name, and name.

Referenced by bzimage_load_initrd(), and efi_file_read_initrd().