From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59882) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e86rM-0003K7-Jt for qemu-devel@nongnu.org; Fri, 27 Oct 2017 11:47:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e86rH-0000Um-Nk for qemu-devel@nongnu.org; Fri, 27 Oct 2017 11:47:48 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:43844 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e86rH-0000UK-HF for qemu-devel@nongnu.org; Fri, 27 Oct 2017 11:47:43 -0400 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v9RFlKWO025392 for ; Fri, 27 Oct 2017 11:47:40 -0400 Received: from e12.ny.us.ibm.com (e12.ny.us.ibm.com [129.33.205.202]) by mx0a-001b2d01.pphosted.com with ESMTP id 2dv5tcq7rd-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 27 Oct 2017 11:47:39 -0400 Received: from localhost by e12.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 27 Oct 2017 11:47:39 -0400 References: <1509114613-10601-1-git-send-email-walling@linux.vnet.ibm.com> <5d039f30-4896-fef3-3b1c-a2be4edcf13b@linux.vnet.ibm.com> From: "Collin L. Walling" Date: Fri, 27 Oct 2017 11:47:37 -0400 MIME-Version: 1.0 In-Reply-To: <5d039f30-4896-fef3-3b1c-a2be4edcf13b@linux.vnet.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Message-Id: <2773f2f1-6b0f-855d-b51e-7e8d5ecd67ab@linux.vnet.ibm.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v3] s390-ccw: print carriage return with new lines List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Halil Pasic , qemu-devel@nongnu.org On 10/27/2017 11:39 AM, Halil Pasic wrote: > > On 10/27/2017 04:30 PM, Collin L. Walling wrote: >> The sclp console in the s390 bios writes raw data, >> leading console emulators (such as virsh console) to >> treat a new line ('\n') as just a new line instead >> of as a Unix line feed. Because of this, output >> appears in a "stair case" pattern. >> >> Let's print \r\n on every occurrence of a new line >> in the string passed to write to amend this issue. >> >> This is in sync with the guest Linux code in >> drivers/s390/char/sclp_vt220.c which also does a line feed >> conversion in the console part of the driver. >> >> This fixes the s390-ccw and s390-netboot output like >> $ virsh start test --console >> Domain test started >> Connected to domain test >> Escape character is ^] >> Network boot starting... >> Using MAC address: 02:01:02:03:04:05 >> Reque= sting information via DHCP: 010 >> >> Signed-off-by: Collin L. Walling >> Signed-off-by: Christian Borntraeger >> --- >> pc-bios/s390-ccw/sclp.c | 24 +++++++++++++++++++++--- >> 1 file changed, 21 insertions(+), 3 deletions(-) >> >> diff --git a/pc-bios/s390-ccw/sclp.c b/pc-bios/s390-ccw/sclp.c >> index 486fce1..a57006e 100644 >> --- a/pc-bios/s390-ccw/sclp.c >> +++ b/pc-bios/s390-ccw/sclp.c >> @@ -68,17 +68,35 @@ void sclp_setup(void) >> long write(int fd, const void *str, size_t len) >> { >> WriteEventData *sccb =3D (void *)_sccb; >> + const char *p =3D str; >> + size_t data_len =3D 0; >> + size_t i; >> >> if (fd !=3D 1 && fd !=3D 2) { >> return -EIO; >> } >> >> - sccb->h.length =3D sizeof(WriteEventData) + len; >> + for (i =3D len; i > 0; i--) > + if (data_len + 1 >=3D SCCB= _DATA_LEN) { >> + /* We would overflow the sccb buffer, abort early */ >> + len =3D i; > This is not correct. Write is supposed to return the number > of bytes written. In this case the number of the bytes of the > original string which have been processed (so the client > code can resume at that place, using the nuber of bytes > transferred via sclp_service_call would be wrong if at least > one \n was processed). > > Here you return the number of the bytes remaining, as i goes > from len to 0 and not the other way around. By the way Alex's > version was correct. Yikes -- thank you for catching this.=C2=A0 I blindly copied. Will fix. > >> + break; >> + } >> + >> + if (*p =3D=3D '\n') { >> + /* Terminal emulators might need \r\n, so generate it */ >> + sccb->data[data_len++] =3D '\r'; >> + } >> + >> + sccb->data[data_len++] =3D *p; >> + p++; >> + } >> + >> + sccb->h.length =3D sizeof(WriteEventData) + data_len; >> sccb->h.function_code =3D SCLP_FC_NORMAL_WRITE; >> - sccb->ebh.length =3D sizeof(EventBufferHeader) + len; >> + sccb->ebh.length =3D sizeof(EventBufferHeader) + data_len; >> sccb->ebh.type =3D SCLP_EVENT_ASCII_CONSOLE_DATA; >> sccb->ebh.flags =3D 0; >> - memcpy(sccb->data, str, len); >> >> sclp_service_call(SCLP_CMD_WRITE_EVENT_DATA, sccb); >> > I would have wrote the loop part like this: > - sccb->h.length =3D sizeof(WriteEventData) + len; > + for (i =3D 0; i < len; ++i) { > + if (data_len + 1 >=3D SCCB_DATA_LEN) { > + /* We would overflow the sccb buffer, abort early */ > + len =3D i; > + break; > + } > + > + if (str[i] =3D=3D '\n') { > + /* Terminal emulators might need \r\n, so generate it */ > + sccb->data[data_len++] =3D '\r'; > + } > + > + sccb->data[data_len++] =3D str[i]; > + } > + > + sccb->h.length =3D sizeof(WriteEventData) + data_len; > > This way you don't need p, and the loop steps trough the str indexed by > i while sccb->data is indexed by data_len. data_len is incremented each > time after we have written to the buffer (that's why postfix ++) > and i is incremented on each iteration (that's why normal prefix ++). > > Btw I would also rename i to str_i and data_len to data_i to better > reflect this. > > The cosmetics aren't important though, so it's probably better to go > with what we have already discussed as Alex's version. > > Regards, > Halil > > > I wanted to do the same, however str is void can cannot be indexed=20 directly. We'd have to do some nasty casting first, so I figured having *p made=20 things look cleaner. I'll post v4 with fixups immediately, but with more care this time. --=20 - Collin L Walling