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#include "v9fs.h"

	.code16
	.section ".rtext","ax"

/* ------------------------------------------------------------------------- *
 *  path_walk
 *
 *  Issue a walk message for the path in FS:SI.
 *  BX marks the end of the path to convert, and EAX is the new fid.
 * ------------------------------------------------------------------------- */

	.globl path_walk
path_walk:
	movw msgbuf7,%di
	movl $ROOT_FID,(%di)
	movl %eax,4(%di)
	addw $8,%di
	pushw %di
	call genpath
	popw %si
	pushw (%di)		/* Number of pathname chunks */
	movb $P9_TWALK,%al
	call simple_message
	jc 1f			/* Message error */
	popw %dx
	movw (%di),%cx		/* %ax = nwqid */
	imul $13,%cx,%bx	/* Each qid is 13 bytes */
	movb $-11(%bx,%di),%al	/* Type of the final QID */
	cmpw %dx,%cx
	jne 2f
	clc			/* All good */
1:
	retw
2:
	/*
	 * We receieved a subset of the desired qids.  If the final
	 * component is a directory, this is ENOENT, otherwise ENOTDIR.
	 */
	testb $P9_QTDIR,%al
	movw $L_ENOENT,%ax
	je 3f
	movw $L_ENOTDIR,%ax
3:
	stc
	retw