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List:       opensolaris-dtrace-discuss
Subject:    Re: [dtrace-discuss] translate byte array to uint64_t
From:       Jonathan Adams <jonathan.adams () sun ! com>
Date:       2009-05-19 19:05:00
Message-ID: 20090519190500.GT163312 () eng ! sun ! com
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On Mon, May 18, 2009 at 04:17:16PM -0400, Priya Krishnan wrote:
> I have a translator related question, One of the members of my native 
> structure is a 8-byte array. In the equivalent D struct, this member is 
> represented as an uint64_t. It is preferable to convert the byte-array 
> to an uint64_t in the translator. Is this possible?

Certainly:

	    (uint64_t)ba[0] << (64 - 0*8 - 8) +
	    (uint64_t)ba[1] << (64 - 1*8 - 8) +
	    (uint64_t)ba[2] << (64 - 2*8 - 8) +
	    (uint64_t)ba[3] << (64 - 3*8 - 8) +
	    (uint64_t)ba[4] << (64 - 4*8 - 8) +
	    (uint64_t)ba[5] << (64 - 5*8 - 8) +
	    (uint64_t)ba[6] << (64 - 6*8 - 8) +
	    (uint64_t)ba[7] << (64 - 7*8 - 8);

If endianess and alignment aren't an issue, you could do *(uint64_t *)ba.

Cheers,
- jonathan

> i.e.  I am looking for an equivalent to the following C program
> uint64_t result = 0;
> char str[256] ;
> 
> snprintf(str, 256, "%x%x%x%x%x%x%x%x",
>            ba[0], ba[1], ba[2], ba[3], ba[4], ba[5], ba[6], ba[7]);
> result = strtoull((char *)ba, NULL, 16);
> 
> Any suggestion is appreciated
> 
> thanks
> Priya
> 
> 
> 
> 
> 
> 
> 
> _______________________________________________
> dtrace-discuss mailing list
> dtrace-discuss@opensolaris.org
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