From nobody Sat Jul 9 16:26:37 2022 X-Original-To: freebsd-hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4838A180857F for ; Sat, 9 Jul 2022 16:26:41 +0000 (UTC) (envelope-from marc@bumblingdork.com) Received: from mail-ed1-x52b.google.com (mail-ed1-x52b.google.com [IPv6:2a00:1450:4864:20::52b]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1D4" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4LgFsD0n1Cz3cZ5 for ; Sat, 9 Jul 2022 16:26:40 +0000 (UTC) (envelope-from marc@bumblingdork.com) Received: by mail-ed1-x52b.google.com with SMTP id r18so1757157edb.9 for ; Sat, 09 Jul 2022 09:26:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bumblingdork.com; s=google; h=from:content-transfer-encoding:mime-version:subject:message-id:date :to; bh=MAYyHjTBzXfRralR4w9DsIGAhxxDfHZqKq6sPTogICE=; b=ZMU/U4PUOujB7itVvI+09kRDMPeO0usL+LCdax93Yos2khe8gOktEBLE79wN8hqjbr oA6Zd+rEXIsuza6erKLyN1jfG7b4fcb4VPsi8ukWdnYT2nE3C5TQOmZd5WAlD4AtATUR Ayed0ObDAil9o+T/ZUR/OGnqKVcgLQ3S0dJGqhVvYXtjW28mzsRjy4t06p7sSsz7dP2D 6J/GgKl1R3PpAHlRXmyLwrDLaZimIe62WBh0bxsWESJzDtsdcmWHzNIQ8cLjJasFY52W qoRHewQtoYtGobW3U4LHMsPkfAKoYjmqYZOPFmBXBT294i+SpFZEPwaG9KG01fBBRpOG AeJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:content-transfer-encoding:mime-version :subject:message-id:date:to; bh=MAYyHjTBzXfRralR4w9DsIGAhxxDfHZqKq6sPTogICE=; b=gcsuktlZ/yHFC/MWtW1YMVGV2BRcU2ari4TH5IfJaBQvqqWfNLfJ4ENL4hR6tQaRox 7dDzKqezqBRPb/AlxiWLPMRR+3Y/o2tCeiKla+EEj7QqjDGH2Kus8FkCZdolDNKo1vrz JRbIg5BYNmbJlH/sZJHPI9Fgd86AtZSxz4Gt2G1BLtbhVt7PQ26Z+o3uSRJ8uLacJlxD SAbxUO/jhr/LtOq1lYlBNFrNAnMxsxrJKifiSeMShQkPE3+l+PRicBJW/n96Tmwh2BnB PE/nJadD8F6YP3WrIF6LciLJ9eQX5zyWy0oUFpanORXh6fSh1qox6uyRbY/90/cIVNDE DaPg== X-Gm-Message-State: AJIora+nxOiJ1VTBCvocD38gUkDF287/7YS4yNqhDgrf1wGrEp8Js1Cx ect/ow8GXu8C0WWj4CqLMiCQCmqz0ITACA== X-Google-Smtp-Source: AGRyM1tLss3LdkZEQOelItQi9/9hN9uFtsdPq66XWgak5/IIbtsDtHfjsCo6IhgZ60Q/5bNFDGaxNg== X-Received: by 2002:a05:6402:4446:b0:43a:3f52:4172 with SMTP id o6-20020a056402444600b0043a3f524172mr12246923edb.417.1657383998445; Sat, 09 Jul 2022 09:26:38 -0700 (PDT) Received: from smtpclient.apple (2a02-a467-ec-1-7443-d497-4af2-1567.fixed6.kpn.net. [2a02:a467:ec:1:7443:d497:4af2:1567]) by smtp.gmail.com with ESMTPSA id s10-20020a1709064d8a00b0072b33e91f96sm729689eju.190.2022.07.09.09.26.37 for (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sat, 09 Jul 2022 09:26:38 -0700 (PDT) From: Marc Veldman Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.120.0.1.13\)) Subject: Canonical way / best practice for 128-bit integers Message-Id: <86CB4C22-9CAB-4578-8F11-962B4B08F756@bumblingdork.com> Date: Sat, 9 Jul 2022 18:26:37 +0200 To: freebsd-hackers@freebsd.org X-Mailer: Apple Mail (2.3654.120.0.1.13) X-Rspamd-Queue-Id: 4LgFsD0n1Cz3cZ5 X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=bumblingdork.com header.s=google header.b="ZMU/U4PU"; dmarc=pass (policy=none) header.from=bumblingdork.com; spf=pass (mx1.freebsd.org: domain of marc@bumblingdork.com designates 2a00:1450:4864:20::52b as permitted sender) smtp.mailfrom=marc@bumblingdork.com X-Spamd-Result: default: False [-3.50 / 15.00]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; NEURAL_HAM_SHORT(-1.00)[-1.000]; MV_CASE(0.50)[]; DMARC_POLICY_ALLOW(-0.50)[bumblingdork.com,none]; R_DKIM_ALLOW(-0.20)[bumblingdork.com:s=google]; R_SPF_ALLOW(-0.20)[+ip6:2a00:1450:4000::/36]; MIME_GOOD(-0.10)[text/plain]; FROM_EQ_ENVFROM(0.00)[]; DKIM_TRACE(0.00)[bumblingdork.com:+]; MLMMJ_DEST(0.00)[freebsd-hackers]; RCVD_TLS_LAST(0.00)[]; RCVD_IN_DNSWL_NONE(0.00)[2a00:1450:4864:20::52b:from]; MIME_TRACE(0.00)[0:+]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCVD_COUNT_THREE(0.00)[3]; RCPT_COUNT_ONE(0.00)[1]; FREEFALL_USER(0.00)[marc]; ARC_NA(0.00)[]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; FROM_HAS_DN(0.00)[]; PREVIOUSLY_DELIVERED(0.00)[freebsd-hackers@freebsd.org]; TO_MATCH_ENVRCPT_ALL(0.00)[]; TO_DN_NONE(0.00)[]; MID_RHS_MATCH_FROM(0.00)[] X-ThisMailContainsUnwantedMimeParts: N Hello, I=E2=80=99m working on some bluetooth code, and that involves handling = 128-bit uuids. There are various ways to handle in the FreeBSD codebase, like in sdp.h: /* * SDP int128/uint128 parameter */ =20 struct int128 { int8_t b[16]; }; typedef struct int128 int128_t; typedef struct int128 uint128_t; and in sys/dev/random/uint128.h #ifdef USE_REAL_UINT128_T typedef __uint128_t uint128_t; #define UINT128_ZERO 0ULL #else typedef struct { /* Ignore endianness */ uint64_t u128t_word0; uint64_t u128t_word1; } uint128_t; static const uint128_t very_long_zero =3D {0UL,0UL}; #define UINT128_ZERO very_long_zero #endif Is there any recommended / standard way to handle 128 bit integers in a = portable way? Best regards, Marc Veldman=