cpio.c File Reference

CPIO archives. More...

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ipxe/cpio.h>

Go to the source code of this file.

Macros
#define	CPIO_DEFAULT_MODE   0644
	CPIO default file mode. More...
#define	CPIO_DEFAULT_DIR_MODE   0755
	CPIO directory mode. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
static void	cpio_set_field (char *field, unsigned long value)
	Set field within a CPIO header. More...
static unsigned int	cpio_max (struct image *image)
	Get maximum number of CPIO headers (i.e. More...
static size_t	cpio_name_len (struct image *image, unsigned int depth)
	Get CPIO image filename. More...
static void	cpio_parse_cmdline (struct image *image, unsigned int *mode, unsigned int *count)
	Parse CPIO image parameters. 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.c.

Macro Definition Documentation

CPIO_DEFAULT_MODE

#define CPIO_DEFAULT_MODE   0644

CPIO default file mode.

Definition at line 38 of file cpio.c.

CPIO_DEFAULT_DIR_MODE

#define CPIO_DEFAULT_DIR_MODE   0755

CPIO directory mode.

Definition at line 41 of file cpio.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

cpio_set_field()

static void cpio_set_field ( char *  field, unsigned long  value  )

static

Set field within a CPIO header.

Parameters

field	Field within CPIO header
value	Value to set

Definition at line 49 of file cpio.c.

                                                                {
        char buf[9];

        snprintf ( buf, sizeof ( buf ), "%08lx", value );
        memcpy ( field, buf, 8 );
}

References memcpy(), snprintf(), and value.

Referenced by cpio_header().

cpio_max()

static unsigned int cpio_max ( struct image *  image )

static

Get maximum number of CPIO headers (i.e.

number of path components)

Parameters

image

Image

Return values

max	Maximum number of CPIO headers

Definition at line 62 of file cpio.c.

                                                     {
        const char *name = cpio_name ( image );
        unsigned int max = 0;
        char c;
        char p;

        /* Check for existence of CPIO filename */
        if ( ! name )
                return 0;

        /* Count number of path components */
        for ( p = '/' ; ( ( ( c = *(name++) ) ) && ( c != ' ' ) ) ; p = c ) {
                if ( ( p == '/' ) && ( c != '/' ) )
                        max++;
        }

        return max;
}

References cpio_name(), max, and name.

Referenced by cpio_header().

cpio_name_len()

static size_t cpio_name_len ( struct image *  image, unsigned int  depth  )

static

Get CPIO image filename.

Parameters

image	Image
depth	Path depth

Return values

len	Filename length

Definition at line 88 of file cpio.c.

                                                                        {
        const char *name = cpio_name ( image );
        size_t len;
        char c;
        char p;

        /* Sanity checks */
        assert ( name != NULL );
        assert ( depth > 0 );

        /* Calculate length up to specified path depth */
        for ( len = 0, p = '/' ; ( ( ( c = name[len] ) ) && ( c != ' ' ) ) ;
              len++, p = c ) {
                if ( ( c == '/' ) && ( p != '/' ) && ( --depth == 0 ) )
                        break;
        }

        return len;
}

References assert(), cpio_name(), len, name, and NULL.

Referenced by cpio_header().

cpio_parse_cmdline()

static void cpio_parse_cmdline ( struct image *  image, unsigned int *  mode, unsigned int *  count  )

static

Parse CPIO image parameters.

Parameters

image	Image
mode	Mode to fill in
count	Number of CPIO headers to fill in

Definition at line 115 of file cpio.c.

                                                       {
        const char *arg;
        char *end;

        /* Set default values */
        *mode = CPIO_DEFAULT_MODE;
        *count = 1;

        /* Parse "mode=...", if present */
        if ( ( arg = image_argument ( image, "mode=" ) ) ) {
                *mode = strtoul ( arg, &end, 8 /* Octal for file mode */ );
                if ( *end && ( *end != ' ' ) ) {
                        DBGC ( image, "CPIO %s strange \"mode=\" "
                               "terminator '%c'\n", image->name, *end );
                }
        }

        /* Parse "mkdir=...", if present */
        if ( ( arg = image_argument ( image, "mkdir=" ) ) ) {
                *count += strtoul ( arg, &end, 10 );
                if ( *end && ( *end != ' ' ) ) {
                        DBGC ( image, "CPIO %s strange \"mkdir=\" "
                               "terminator '%c'\n", image->name, *end );
                }
        }

        /* Allow "mkdir=-1" to request creation of full directory tree */
        if ( ! *count )
                *count = -1U;
}

References count, CPIO_DEFAULT_MODE, DBGC, end, image_argument(), mode, image::name, and strtoul().

Referenced by cpio_header().

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 155 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 );

        /* Set directory mode or file mode as appropriate */
        if ( name[name_len] == '/' ) {
                mode = ( CPIO_MODE_DIR | CPIO_DEFAULT_DIR_MODE );
        } else {
                mode |= CPIO_MODE_FILE;
        }

        /* Set length on final header */
        len = ( ( depth < max ) ? 0 : 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, image::len, len, max, memcpy(), memset(), mode, image::name, and name.

Referenced by cpio_okx(), efi_file_read_initrd(), and initrd_load().