strdup.s

用于嵌入式Linux系统的标准C的库函数

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 * 
 * Copyright (c) 1993 Intel Corporation
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	.file "strdup.s"
#ifdef	__PIC
	.pic
#endif
#ifdef	__PID
	.pid
#endif

/*
 * (c) copyright 1989,1993 Intel Corp., all rights reserved
 */

/*
	procedure strdup  (optimized assembler version: 80960K series, 80960CA)

	dest_addr = strdup (src_addr)

	Allocate memory and copy thereto the string pointed to by src_addr.
	Return the address of the copy, or null if unable to perform the
	operation.
*/

	.text
	.align	2
	.globl	_strdup
_strdup:
	mov	g0,r3		# Keep a copy of the original string addr
	callj	_strlen		# Determine how much to allocate
	addo	1,g0,g0		# Add one byte for the null byte at end
	callj	_malloc		# Allocate the storage
	cmpo	0,g0
	mov	r3,g1		# Original string addr is now src for copy
	bne.t	_strcpy		# Jump if allocation was successful
	ret			# Return the null ptr otherwise

/* end of strdup */