From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtpng3.m.smailru.net (smtpng3.m.smailru.net [94.100.177.149]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dev.tarantool.org (Postfix) with ESMTPS id 0694142F4AD for ; Thu, 25 Jun 2020 01:23:13 +0300 (MSK) References: From: Vladislav Shpilevoy Message-ID: <5ae054f7-2472-a80c-1b3d-1f89ae40f21a@tarantool.org> Date: Thu, 25 Jun 2020 00:23:12 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Tarantool-patches] [PATCH v2 2/2] Add IsInt method for checking the fractional part of a number List-Id: Tarantool development patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Chris Sosnin , tarantool-patches@dev.tarantool.org, sergepetrenko@tarantool.org Thanks for the patch! Technically looks fine. But see two style comments below. On 24/06/2020 18:53, Chris Sosnin wrote: > Currently there is no efficient way to do this. > > Needed for tarantool/tarantool#4415 > --- > decNumber.c | 27 +++++++++++++++++++++++++++ > decNumber.h | 1 + > 2 files changed, 28 insertions(+) > > diff --git a/decNumber.c b/decNumber.c > index e248656..26acec3 100644 > --- a/decNumber.c > +++ b/decNumber.c > @@ -501,6 +501,33 @@ uLong decNumberToUInt64(const decNumber *dn, decContext *set) { > return 0; > } // decNumberToUInt64 > > +Flag decNumberIsInt(const decNumber *dn) { 1. It seems Flag type is internal. For public API flags the lib uses int32_t. For example, look at decNumberIsNormal(), decNumberIsSubnormal(). > + const Unit *up=dn->lsu; > + if (dn->exponent>=0) { > + return 1; > + } > + else { > + Int count=-dn->exponent; > + // spin up whole units until reach the Unit with the unit digit > + for (; count>=DECDPUN; up++) { > + if (*up!=0) return 0; > + count-=DECDPUN; > + } > + if (count==0) return 1; // [a multiple of DECDPUN] > + else { // [not multiple of DECDPUN] > + Int rem; // work > + // slice off fraction digits and check for non-zero > + #if DECDPUN<=4 > + rem=*up-QUOT10(*up, count)*powers[count]; > + #else > + rem=*up%powers[count]; // slice off discards > + #endif > + if (rem!=0) return 0; > + } > + } > + return 1; > + } // decNumberIsInt > + > /* ------------------------------------------------------------------ */ > /* to-scientific-string -- conversion to numeric string */ > /* to-engineering-string -- conversion to numeric string */ > diff --git a/decNumber.h b/decNumber.h > index ffaa3d8..9d3a7e1 100644 > --- a/decNumber.h > +++ b/decNumber.h > @@ -169,6 +169,7 @@ > decNumber * decNumberTrim(decNumber *); > const char * decNumberVersion(void); > decNumber * decNumberZero(decNumber *); > + uint8_t decNumberIsInt(const decNumber *dn); 2. Better move this to the other Is functions a few lines below. Where the comment says "Functions for testing decNumbers". > > /* Functions for testing decNumbers (normality depends on context) */ > int32_t decNumberIsNormal(const decNumber *, decContext *); >