From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40431) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dk4bg-0000Di-HI for qemu-devel@nongnu.org; Tue, 22 Aug 2017 04:32:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dk4bb-0003iN-Kv for qemu-devel@nongnu.org; Tue, 22 Aug 2017 04:32:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46010) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dk4bb-0003hs-Eu for qemu-devel@nongnu.org; Tue, 22 Aug 2017 04:32:11 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7AE51356F9 for ; Tue, 22 Aug 2017 08:32:10 +0000 (UTC) Date: Tue, 22 Aug 2017 04:32:08 -0400 (EDT) From: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau Message-ID: <1341095109.1432760.1503390728412.JavaMail.zimbra@redhat.com> In-Reply-To: <1503384739-17207-1-git-send-email-armbru@redhat.com> References: <1503384739-17207-1-git-send-email-armbru@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH] qobject: Explain how QNum works, and why List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: qemu-devel@nongnu.org, mreitz@redhat.com ----- Original Message ----- > Suggested-by: Max Reitz > Signed-off-by: Markus Armbruster Reviewed-by: Marc-Andr=C3=A9 Lureau > --- > include/qapi/qmp/qnum.h | 21 +++++++++++++++++++++ > 1 file changed, 21 insertions(+) >=20 > diff --git a/include/qapi/qmp/qnum.h b/include/qapi/qmp/qnum.h > index 09d745c..9182129 100644 > --- a/include/qapi/qmp/qnum.h > +++ b/include/qapi/qmp/qnum.h > @@ -23,6 +23,27 @@ typedef enum { > QNUM_DOUBLE > } QNumKind; > =20 > +/* > + * QNum encapsulates how our dialect of JSON fills in the blanks left > + * by the JSON specification (RFC 7159) regarding numbers. > + * > + * Conceptually, we treat number as an abstract type with three > + * concrete subtypes: floating-point, signed integer, unsigned > + * integer. QNum implements this a discriminated union of double, > + * int64_t, uint64_t. > + * > + * The JSON parser picks the subtype as follows. If the number has a > + * decimal point or an exponent, it is floating-point. Else if it > + * fits into int64_t, it's signed integer. Else if it first into > + * uint64_t, it's unsigned integer. Else it's floating-point. > + * > + * Any number can serve as double: qnum_get_double() converts under > + * the hood. > + * > + * An integer can serve as signed / unsigned integer as long as it is > + * in range: qnum_get_try_int() / qnum_get_try_uint() check range and > + * convert under the hood. > + */ > typedef struct QNum { > QObject base; > QNumKind kind; > -- > 2.7.5 >=20 >=20