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/*
* 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;
}
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