Add RFC2090 TFTP multicast support.

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 */

src/include/gpxe/errfile.h

@@ -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 )