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Add RFC2090 TFTP multicast support.
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Michael Brown committed Nov 28, 2007
1 parent f770744 commit 3b1efba
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Showing 4 changed files with 481 additions and 82 deletions.
97 changes: 97 additions & 0 deletions src/core/bitmap.c
@@ -0,0 +1,97 @@
/*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <errno.h>
#include <gpxe/bitmap.h>

/** @file
*
* Bitmaps for multicast downloads
*
*/

/**
* Resize bitmap
*
* @v bitmap Bitmap
* @v new_length New length of bitmap, in bits
* @ret rc Return status code
*/
int bitmap_resize ( struct bitmap *bitmap, unsigned int new_length ) {
unsigned int old_num_blocks;
unsigned int new_num_blocks;
size_t new_size;
bitmap_block_t *new_blocks;

old_num_blocks = BITMAP_INDEX ( bitmap->length + BITMAP_BLKSIZE - 1 );
new_num_blocks = BITMAP_INDEX ( new_length + BITMAP_BLKSIZE - 1 );

new_size = ( new_num_blocks * sizeof ( bitmap->blocks[0] ) );
new_blocks = realloc ( bitmap->blocks, new_size );
if ( ! new_blocks ) {
DBGC ( bitmap, "Bitmap %p could not resize to %d bits\n",
bitmap, new_length );
return -ENOMEM;
}
bitmap->blocks = new_blocks;
bitmap->length = new_length;

while ( old_num_blocks < new_num_blocks ) {
bitmap->blocks[old_num_blocks++] = 0;
}

DBGC ( bitmap, "Bitmap %p resized to %d bits\n", bitmap, new_length );
return 0;
}

/**
* Test bit in bitmap
*
* @v bitmap Bitmap
* @v bit Bit index
* @ret is_set Bit is set
*/
int bitmap_test ( struct bitmap *bitmap, unsigned int bit ) {
unsigned int index = BITMAP_INDEX ( bit );
bitmap_block_t mask = BITMAP_MASK ( bit );

if ( bit >= bitmap->length )
return 0;
return ( bitmap->blocks[index] & mask );
}

/**
* Set bit in bitmap
*
* @v bitmap Bitmap
* @v bit Bit index
*/
void bitmap_set ( struct bitmap *bitmap, unsigned int bit ) {
unsigned int index = BITMAP_INDEX ( bit );
bitmap_block_t mask = BITMAP_MASK ( bit );

DBGC ( bitmap, "Bitmap %p setting bit %d\n", bitmap, bit );

/* Update bitmap */
bitmap->blocks[index] |= mask;

/* Update first gap counter */
while ( bitmap_test ( bitmap, bitmap->first_gap ) ) {
bitmap->first_gap++;
}
}
83 changes: 83 additions & 0 deletions src/include/gpxe/bitmap.h
@@ -0,0 +1,83 @@
#ifndef _GPXE_BITMAP_H
#define _GPXE_BITMAP_H

/** @file
*
* Bitmaps for multicast downloads
*
*/

#include <stdint.h>
#include <stddef.h>
#include <stdlib.h>

/** A single block of bits within a bitmap */
typedef unsigned long bitmap_block_t;

/** Size of a block of bits (in bits) */
#define BITMAP_BLKSIZE ( sizeof ( bitmap_block_t ) * 8 )

/**
* Block index within bitmap
*
* @v bit Bit index
* @ret index Block index
*/
#define BITMAP_INDEX( bit ) ( (bit) / BITMAP_BLKSIZE )

/**
* Block mask within bitmap
*
* @v bit Bit index
* @ret mask Block mask
*/
#define BITMAP_MASK( bit ) ( 1 << ( (bit) % BITMAP_BLKSIZE ) )

/** A bitmap */
struct bitmap {
/** Bitmap data */
bitmap_block_t *blocks;
/** Length of the bitmap, in bits */
unsigned int length;
/** Index of first gap in the bitmap */
unsigned int first_gap;
};

extern int bitmap_resize ( struct bitmap *bitmap, unsigned int new_length );
extern int bitmap_test ( struct bitmap *bitmap, unsigned int bit );
extern void bitmap_set ( struct bitmap *bitmap, unsigned int bit );

/**
* Free bitmap resources
*
* @v bitmap Bitmap
*/
static inline void bitmap_free ( struct bitmap *bitmap ) {
free ( bitmap->blocks );
}

/**
* Get first gap within bitmap
*
* @v bitmap Bitmap
* @ret first_gap First gap
*
* The first gap is the first unset bit within the bitmap.
*/
static inline unsigned int bitmap_first_gap ( struct bitmap *bitmap ) {
return bitmap->first_gap;
}

/**
* Check to see if bitmap is full
*
* @v bitmap Bitmap
* @ret is_full Bitmap is full
*
* The bitmap is full if it has no gaps (i.e. no unset bits).
*/
static inline int bitmap_full ( struct bitmap *bitmap ) {
return ( bitmap->first_gap == bitmap->length );
}

#endif /* _GPXE_BITMAP_H */
1 change: 1 addition & 0 deletions src/include/gpxe/errfile.h
Expand Up @@ -50,6 +50,7 @@
#define ERRFILE_settings ( ERRFILE_CORE | 0x000c0000 )
#define ERRFILE_vsprintf ( ERRFILE_CORE | 0x000d0000 )
#define ERRFILE_xfer ( ERRFILE_CORE | 0x000e0000 )
#define ERRFILE_bitmap ( ERRFILE_CORE | 0x000f0000 )

#define ERRFILE_eisa ( ERRFILE_DRIVER | 0x00000000 )
#define ERRFILE_isa ( ERRFILE_DRIVER | 0x00010000 )
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