Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 19 Jul 2002 00:53:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 19 Jul 2002 00:53:47 -0400 Received: from p50887DBB.dip.t-dialin.net ([80.136.125.187]:27008 "EHLO hawkeye.luckynet.adm") by vger.kernel.org with ESMTP id ; Fri, 19 Jul 2002 00:53:45 -0400 Date: Thu, 18 Jul 2002 22:55:58 -0600 (MDT) From: Thunder from the hill X-X-Sender: thunder@hawkeye.luckynet.adm To: James Antill cc: Linux Kernel Mailing List Subject: Re: more thoughts on a new jail() system call In-Reply-To: Message-ID: X-Location: Dorndorf; Germany MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="-1463811839-1262670546-1027054558=:3378" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7656 Lines: 142 This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. Send mail to mime@docserver.cac.washington.edu for more info. ---1463811839-1262670546-1027054558=:3378 Content-Type: TEXT/PLAIN; charset=US-ASCII Hi, On 19 Jul 2002, James Antill wrote: > The more general spelling is FIONREAD, and I generally find that only > crap network applications need to use it. Good ones just try and read > a largish amount of data into a buffer. That doesn't matter as long as you haven't got any idea on how much data will be read. Especially relaying between two completely different hosts, possibly unknown protocols, you don't have a chance to know who will send next. Without TIOCINQ you'll almost be shot if you have received lots of lots of stuff from the client and expect any response from the server. You just won't get it. Give me another version of the appended piece of code that won't use ioctl, and I'll consider an acknowledgement. Regards, Thunder -- (Use http://www.ebb.org/ungeek if you can't decode) ------BEGIN GEEK CODE BLOCK------ Version: 3.12 GCS/E/G/S/AT d- s++:-- a? C++$ ULAVHI++++$ P++$ L++++(+++++)$ E W-$ N--- o? K? w-- O- M V$ PS+ PE- Y- PGP+ t+ 5+ X+ R- !tv b++ DI? !D G e++++ h* r--- y- ------END GEEK CODE BLOCK------ ---1463811839-1262670546-1027054558=:3378 Content-Type: TEXT/PLAIN; charset=US-ASCII; name="portforwarder.c" Content-Transfer-Encoding: BASE64 Content-ID: Content-Description: Content-Disposition: attachment; filename="portforwarder.c" I2luY2x1ZGUgPGVycm5vLmg+DQojaW5jbHVkZSA8c3RkaW8uaD4NCiNpbmNs dWRlIDxzdGRsaWIuaD4NCiNpbmNsdWRlIDxzdHJpbmcuaD4NCiNpbmNsdWRl IDx1bmlzdGQuaD4NCiNpbmNsdWRlIDxhcnBhL2luZXQuaD4NCiNpbmNsdWRl IDxzeXMvaW9jdGwuaD4NCiNpbmNsdWRlIDxuZXRpbmV0L2luLmg+DQojaW5j bHVkZSA8c3lzL3NvY2tldC5oPg0KDQojZGVmaW5lIF9wZXJyb3IocykgcGVy cm9yKHMpOyBlcnJubyA9IDANCiNkZWZpbmUgX3Byb2JhYmx5X3BlcnJvcihz KSBpZiAoZXJybm8pIHsgcGVycm9yKHMpOyBlcnJubyA9IDA7IH0NCg0KdW5z aWduZWQgc2hvcnQgcG9ydGZyb20sIHBvcnR0bzsNCmludCBzb2NrLCBjbGll bnQsIHNlcnZlciwgcGVlcl9zaXplOw0Kc3RydWN0IHNvY2thZGRyX2luICps b2NhbCwgKnBlZXIsICpyZW1vdGU7DQpjaGFyICpidWZmZXI7DQoNCmludCBt YWluKGludCBhcmdjLCBjaGFyICoqYXJndikgew0KCWJ1ZmZlciAgICA9IG1h bGxvYyg2NTUzNyk7DQoJcmVtb3RlICAgID0gbWFsbG9jKHNpemVvZihzdHJ1 Y3Qgc29ja2FkZHJfaW4pKTsNCglsb2NhbCAgICAgPSBtYWxsb2Moc2l6ZW9m KHN0cnVjdCBzb2NrYWRkcl9pbikpOw0KCXBlZXIgICAgICA9IG1hbGxvYyhz aXplb2Yoc3RydWN0IHNvY2thZGRyX2luKSk7DQoJcGVlcl9zaXplID0gc2l6 ZW9mKHN0cnVjdCBzb2NrYWRkcl9pbik7DQoJcG9ydGZyb20gID0gMjY7DQoJ cG9ydHRvICAgID0gMjU7DQoNCglpZiAoYXJnYyA+PSAzKSB7DQoJCXBvcnRm cm9tID0gKHNob3J0KShhdG9sKGFyZ3ZbMV0pICYgMHhGRkZGKTsNCgkJcG9y dHRvICAgPSAoc2hvcnQpKGF0b2woYXJndlsyXSkgJiAweEZGRkYpOw0KCX0N Cg0KCWxvY2FsLT5zaW5fZmFtaWx5ICAgICAgID0gQUZfSU5FVDsNCglsb2Nh bC0+c2luX3BvcnQgICAgICAgICA9IGh0b25zKHBvcnRmcm9tKTsNCglsb2Nh bC0+c2luX2FkZHIuc19hZGRyICA9IGh0b25sKElOQUREUl9BTlkpOw0KDQoJ cmVtb3RlLT5zaW5fZmFtaWx5ICAgICAgPSBBRl9JTkVUOw0KCXJlbW90ZS0+ c2luX3BvcnQgICAgICAgID0gaHRvbnMocG9ydHRvKTsNCglyZW1vdGUtPnNp bl9hZGRyLnNfYWRkciA9IGluZXRfYWRkcigiMTkyLjE2OC4xLjEiKTsNCg0K CXByaW50ZigiVGFyZ2V0IGFkZHJlc3M6ICVpLiVpLiVpLiVpOiVpXG4iLA0K CSAgICAgICByZW1vdGUtPnNpbl9hZGRyLnNfYWRkciAmIDB4RkYsDQoJICAg ICAgIChyZW1vdGUtPnNpbl9hZGRyLnNfYWRkciA+PiA4KSAmIDB4RkYsDQoJ ICAgICAgIChyZW1vdGUtPnNpbl9hZGRyLnNfYWRkciA+PiAxNikgJiAweEZG LA0KCSAgICAgICAocmVtb3RlLT5zaW5fYWRkci5zX2FkZHIgPj4gMjQpICYg MHhGRiwNCgkgICAgICAgbnRvaHMocmVtb3RlLT5zaW5fcG9ydCkpOw0KDQoJ c29jayA9IHNvY2tldChQRl9JTkVULCBTT0NLX1NUUkVBTSwgSVBQUk9UT19U Q1ApOw0KCWlmIChzb2NrID09IC0xKSB7DQoJCV9wZXJyb3IoInNvY2tldCAo Y29udHJvbGxlcikiKTsNCgkJZXhpdCgxKTsNCgl9DQoJaWYgKGJpbmQoc29j aywgKHN0cnVjdCBzb2NrYWRkciAqKWxvY2FsLA0KCQkgc2l6ZW9mKHN0cnVj dCBzb2NrYWRkcl9pbikpIDwgMCkgew0KCQlfcGVycm9yKCJiaW5kIik7DQoJ CWV4aXQoMSk7DQoJfQ0KCWlmIChsaXN0ZW4oc29jaywgMTApIDwgMCkgew0K CQlfcGVycm9yKCJsaXN0ZW4iKTsNCgkJZXhpdCgxKTsNCgl9DQoJd2hpbGUg KChjbGllbnQgPSBhY2NlcHQoc29jaywgKHN0cnVjdCBzb2NrYWRkciAqKXBl ZXIsDQoJCQkJJnBlZXJfc2l6ZSkpID49IDApIHsNCgkJdW5zaWduZWQgbG9u ZyBzOw0KCQlpbnQgaW5fcmVjdnEsIG92ZXJoZWFkID0gMCwgbnJfbG9vcHMg PSAwOw0KDQoJCWZvciAocyA9IDA7IHMgPCA2NTUzNjsgcysrKQ0KCQkJYnVm ZmVyW3NdID0gMDsNCg0KCQlwcmludGYoIkNvbm5lY3Rpb24gZnJvbSAlczol aVxuIiwNCgkJICAgICAgIGluZXRfbnRvYShwZWVyLT5zaW5fYWRkciksDQoJ CSAgICAgICBudG9ocyhwZWVyLT5zaW5fcG9ydCkpOw0KDQoJCXNlcnZlciA9 IHNvY2tldChQRl9JTkVULCBTT0NLX1NUUkVBTSwgSVBQUk9UT19UQ1ApOw0K CQlpZiAoc2VydmVyID09IC0xKSB7DQoJCQlfcGVycm9yKCJzb2NrZXQgKHNl cnZlcikiKTsNCgkJCWV4aXQoMSk7DQoJCX0NCgkJaWYgKGNvbm5lY3Qoc2Vy dmVyLCAoc3RydWN0IHNvY2thZGRyICopcmVtb3RlLA0KCQkJICAgIHNpemVv ZihzdHJ1Y3Qgc29ja2FkZHJfaW4pKSA8IDApIHsNCgkJCV9wZXJyb3IoImNv bm5lY3QgKHNlcnZlcikiKTsNCgkJCWdvdG8gb3V0Ow0KCQl9DQoNCgkJcHJp bnRmKCJTZXJ2ZXIgY29ubmVjdGlvbiBpcyB1cC5cbiIpOw0KCQl1c2xlZXAo MTAwKTsNCg0KCQlpZiAoaW9jdGwoc2VydmVyLCBUSU9DSU5RLCAmaW5fcmVj dnEpICE9IDApIHsNCgkJCV9wZXJyb3IoIlRJT0NJTlEgKHNlcnZlcikiKTsN CgkJCWdvdG8gb3V0Ow0KCQl9DQoNCglkYXRhX3dhaXRpbmc6DQoJCWlmIChv dmVyaGVhZCAtIG5yX2xvb3BzID49IDEwMCkNCgkJCWdvdG8gb3V0Ow0KDQoJ CXdoaWxlIChpbl9yZWN2cSkgew0KCQkJbnJfbG9vcHMrKzsNCgkJCW92ZXJo ZWFkID0gbnJfbG9vcHM7DQoJCQlmb3IgKHMgPSAwOyBzIDwgNjU1MzY7IHMr KykNCgkJCQlidWZmZXJbc10gPSAwOw0KDQoJCQlpZiAocmVjdihzZXJ2ZXIs YnVmZmVyLCA2NTUzNSwgMCkgPCAwKSB7DQoJCQkJX3BlcnJvcigicmVjdiAo c2VydmVyKSIpOw0KCQkJCWdvdG8gb3V0Ow0KCQkJfQ0KCQkJcHJpbnRmKCIl cyIsIGJ1ZmZlcik7DQoJCQlpZiAoc2VuZChjbGllbnQsIGJ1ZmZlciwgc3Ry bGVuKGJ1ZmZlciksIDApIDwgMCkgew0KCQkJCV9wZXJyb3IoInNlbmQgKHNl cnZlcikiKTsNCgkJCQlnb3RvIG91dDsNCgkJCX0NCgkJCWlmIChpb2N0bChz ZXJ2ZXIsIFRJT0NJTlEsICZpbl9yZWN2cSkgIT0gMCkgew0KCQkJCV9wZXJy b3IoIlRJT0NJTlEgKHNlcnZlcikiKTsNCgkJCQlnb3RvIG91dDsNCgkJCX0N CgkJfQ0KDQoJCWlmIChpb2N0bChjbGllbnQsIFRJT0NJTlEsICZpbl9yZWN2 cSkgIT0gMCkgew0KCQkJX3BlcnJvcigiVElPQ0lOUSAoY2xpZW50KSIpOw0K CQkJZ290byBvdXQ7DQoJCX0NCg0KCQl3aGlsZSAoaW5fcmVjdnEpIHsNCgkJ CW5yX2xvb3BzKys7DQoJCQlvdmVyaGVhZCA9IG5yX2xvb3BzOw0KCQkJZm9y IChzID0gMDsgcyA8IDY1NTM2OyBzKyspDQoJCQkJYnVmZmVyW3NdID0gMDsN Cg0KCQkJaWYgKHJlY3YoY2xpZW50LCBidWZmZXIsIDY1NTM1LCAwKSA8IDAp IHsNCgkJCQlfcGVycm9yKCJyZWN2IChjbGllbnQpIik7DQoJCQkJZ290byBv dXQ7DQoJCQl9DQoJCQlwcmludGYoIiVzIiwgYnVmZmVyKTsNCgkJCWlmIChz ZW5kKHNlcnZlciwgYnVmZmVyLCBzdHJsZW4oYnVmZmVyKSwgMCkgPCAwKSB7 DQoJCQkJX3BlcnJvcigic2VuZCAoc2VydmVyKSIpOw0KCQkJCWdvdG8gb3V0 Ow0KCQkJfQ0KCQkJaWYgKGlvY3RsKGNsaWVudCwgVElPQ0lOUSwgJmluX3Jl Y3ZxKSAhPSAwKSB7DQoJCQkJX3BlcnJvcigiVElPQ0lOUSAoY2xpZW50KSIp Ow0KCQkJCWdvdG8gb3V0Ow0KCQkJfQ0KCQl9DQoNCgkJaWYgKGlvY3RsKHNl cnZlciwgVElPQ0lOUSwgJmluX3JlY3ZxKSAhPSAwKSB7DQoJCQlfcGVycm9y KCJUSU9DSU5RIChzZXJ2ZXIpIik7DQoJCQlnb3RvIG91dDsNCgkJfQ0KDQoJ CW92ZXJoZWFkKys7DQoNCgkJdXNsZWVwKDEwMCk7DQoJCWdvdG8gZGF0YV93 YWl0aW5nOw0KCW91dDoNCgkJcHJpbnRmKCJDb25uZWN0aW9uIGNsb3Npbmcu XG4iKTsNCgkJc2h1dGRvd24oY2xpZW50LCBTSFVUX1JEV1IpOw0KCQlfcHJv YmFibHlfcGVycm9yKCJzaHV0ZG93biAoY2xpZW50KSIpOw0KCQlzaHV0ZG93 bihzZXJ2ZXIsIFNIVVRfUkRXUik7DQoJCV9wcm9iYWJseV9wZXJyb3IoInNo dXRkb3duIChzZXJ2ZXIpIik7DQoJCWNsb3NlKGNsaWVudCk7DQoJCV9wcm9i YWJseV9wZXJyb3IoImNsb3NlIChjbGllbnQpIik7DQoJCWNsb3NlKHNlcnZl cik7DQoJCV9wcm9iYWJseV9wZXJyb3IoImNsb3NlIChzZXJ2ZXIpIik7DQoJ fQ0KDQoJaWYgKGNsb3NlKHNvY2spKSB7DQoJCV9wZXJyb3IoImNsb3NlIChj b250cm9sbGVyKSIpOw0KCX0NCg0KCWV4aXQoMCk7DQp9DQoNCi8qDQogKiBM b2NhbCB2YXJpYWJsZXM6DQogKiAgY29tcGlsZS1jb21tYW5kOiAiZ2NjIC1X IC1XYWxsIC1PcyAtbyBwZiBwb3J0Zm9yd2FyZGVyLmMiDQogKiAgYy1iYXNp Yy1vZmZzZXQ6IDgNCiAqIEVuZDoNCiAqLw0K ---1463811839-1262670546-1027054558=:3378-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/