mirror of https://github.com/ipxe/ipxe.git
133 lines
3.4 KiB
C
133 lines
3.4 KiB
C
/*
|
|
* Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
|
|
*
|
|
* This program 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 of the
|
|
* License, or any later version.
|
|
*
|
|
* This program 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 this program; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
|
* 02110-1301, USA.
|
|
*
|
|
* You can also choose to distribute this program under the terms of
|
|
* the Unmodified Binary Distribution Licence (as given in the file
|
|
* COPYING.UBDL), provided that you have satisfied its requirements.
|
|
*/
|
|
|
|
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
|
|
|
|
/** @file
|
|
*
|
|
* CPIO archives
|
|
*
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <ipxe/cpio.h>
|
|
|
|
/**
|
|
* Set field within a CPIO header
|
|
*
|
|
* @v field Field within CPIO header
|
|
* @v value Value to set
|
|
*/
|
|
void cpio_set_field ( char *field, unsigned long value ) {
|
|
char buf[9];
|
|
|
|
snprintf ( buf, sizeof ( buf ), "%08lx", value );
|
|
memcpy ( field, buf, 8 );
|
|
}
|
|
|
|
/**
|
|
* Get CPIO image filename
|
|
*
|
|
* @v image Image
|
|
* @ret len CPIO filename length (0 for no filename)
|
|
*/
|
|
size_t cpio_name_len ( struct image *image ) {
|
|
const char *name = cpio_name ( image );
|
|
char *sep;
|
|
size_t len;
|
|
|
|
/* Check for existence of CPIO filename */
|
|
if ( ! name )
|
|
return 0;
|
|
|
|
/* Locate separator (if any) */
|
|
sep = strchr ( name, ' ' );
|
|
len = ( sep ? ( ( size_t ) ( sep - name ) ) : strlen ( name ) );
|
|
|
|
return len;
|
|
}
|
|
|
|
/**
|
|
* Parse CPIO image parameters
|
|
*
|
|
* @v image Image
|
|
* @v cpio CPIO header to fill in
|
|
*/
|
|
static void cpio_parse_cmdline ( struct image *image,
|
|
struct cpio_header *cpio ) {
|
|
const char *cmdline;
|
|
char *arg;
|
|
char *end;
|
|
unsigned int mode;
|
|
|
|
/* Skip image filename */
|
|
cmdline = ( cpio_name ( image ) + cpio_name_len ( image ) );
|
|
|
|
/* Look for "mode=" */
|
|
if ( ( arg = strstr ( cmdline, "mode=" ) ) ) {
|
|
arg += 5;
|
|
mode = strtoul ( arg, &end, 8 /* Octal for file mode */ );
|
|
if ( *end && ( *end != ' ' ) ) {
|
|
DBGC ( image, "CPIO %p strange \"mode=\" "
|
|
"terminator '%c'\n", image, *end );
|
|
}
|
|
cpio_set_field ( cpio->c_mode, ( 0100000 | mode ) );
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Construct CPIO header for image, if applicable
|
|
*
|
|
* @v image Image
|
|
* @v cpio CPIO header to fill in
|
|
* @ret len Length of magic CPIO header (including filename)
|
|
*/
|
|
size_t cpio_header ( struct image *image, struct cpio_header *cpio ) {
|
|
size_t name_len;
|
|
size_t len;
|
|
|
|
/* Get filename length */
|
|
name_len = cpio_name_len ( image );
|
|
|
|
/* Images with no filename are assumed to already be CPIO archives */
|
|
if ( ! name_len )
|
|
return 0;
|
|
|
|
/* Construct CPIO header */
|
|
memset ( cpio, '0', sizeof ( *cpio ) );
|
|
memcpy ( cpio->c_magic, CPIO_MAGIC, sizeof ( cpio->c_magic ) );
|
|
cpio_set_field ( cpio->c_mode, 0100644 );
|
|
cpio_set_field ( cpio->c_nlink, 1 );
|
|
cpio_set_field ( cpio->c_filesize, image->len );
|
|
cpio_set_field ( cpio->c_namesize, ( name_len + 1 /* NUL */ ) );
|
|
cpio_parse_cmdline ( image, cpio );
|
|
|
|
/* Calculate total length */
|
|
len = ( ( sizeof ( *cpio ) + name_len + 1 /* NUL */ + CPIO_ALIGN - 1 )
|
|
& ~( CPIO_ALIGN - 1 ) );
|
|
|
|
return len;
|
|
}
|