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Re: call for API review: new bitstring functions

From: Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx>
Date: Fri, 2 Jan 2004 11:20:30 -0800 (PST)

    If I understand this correctly, Jeff, you want to have bitstring
    functions that return the bit number directly rather then into a
    return pointer.

    Max, as far as I can tell Jeff's functions do not use the *value
    construct, they return the bit number directly.  Was that a type-o,
    or am I misunderstanding the issue?

    I agree.  I presume that the bitstring array format will be the same as
    is used in bit_ffs() and friends?  

    Then it just comes down to the name.  'range' is a misnomer.  Maybe
    something like 'quick', e.g. bit_ffs_quick(), to put whoever originally
    came up with the 'int *value' design in his place.  I dunno :-)

					Matthew Dillon 

:On Friday 02 January 2004 08:28, Jeffrey Hsu wrote:
:> I need to find the first and last bit set within a subrange of an array
:> of bits.  Rather than make up an adhoc API for these two functions, I
:> propose adding the following general functions to the bitstring(3) API:
:> /* Return the first bit set in the range [n, m] or -1 if none found. */
:> int bit_ffsrange(bitstr_t *name, int n, int m)
:> /* Return the highest (last) bit set in the range [n, m] or -1 if none
:> found. */
:> int bit_lfsrange(bitstr_t *name, int n, int m)
:> 							Jeffrey
:AFAIR, bitstring is "macro centric" and uses an additional reference to return 
:values, you'd like to keep that?! Apart from that I dislike the naming a bit 
:and would rather go for: bit_rffs(), bit_rfls() ... as it is already used for 
:the bit_n*-class functions.
:btw, bit_lfsrange() should be bit_flsrange() IMO as it spells FindLastSet and 
:FindFirstSet not LastFindSet.
:Best regards,				| max@xxxxxxxxxxxxxx
:Max Laier				| ICQ #67774661

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