From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/5165 Path: news.gmane.org!not-for-mail From: Rich Felker Newsgroups: gmane.linux.lib.musl.general Subject: Re: [UGLY PATCH v2] Support for no-legacy-syscalls archs Date: Mon, 26 May 2014 17:54:12 -0400 Message-ID: <20140526215412.GA507@brightrain.aerifal.cx> References: <20140525054237.GA18085@brightrain.aerifal.cx> <20140526184036.GZ507@brightrain.aerifal.cx> <20140526211349.GJ12324@port70.net> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1401141274 19409 80.91.229.3 (26 May 2014 21:54:34 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 26 May 2014 21:54:34 +0000 (UTC) To: musl@lists.openwall.com Original-X-From: musl-return-5170-gllmg-musl=m.gmane.org@lists.openwall.com Mon May 26 23:54:27 2014 Return-path: Envelope-to: gllmg-musl@plane.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1Wp2qf-0002lP-1W for gllmg-musl@plane.gmane.org; Mon, 26 May 2014 23:54:25 +0200 Original-Received: (qmail 24357 invoked by uid 550); 26 May 2014 21:54:24 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 24342 invoked from network); 26 May 2014 21:54:24 -0000 Content-Disposition: inline In-Reply-To: <20140526211349.GJ12324@port70.net> User-Agent: Mutt/1.5.21 (2010-09-15) Original-Sender: Rich Felker Xref: news.gmane.org gmane.linux.lib.musl.general:5165 Archived-At: On Mon, May 26, 2014 at 11:13:49PM +0200, Szabolcs Nagy wrote: > * Rich Felker [2014-05-26 14:40:36 -0400]: > > +#ifdef SYS_fork > > ret = syscall(SYS_fork); > > +#else > > + ret = syscall(SYS_clone, SIGCHLD); > > +#endif > > clone has more args The remaining args are only read if flags!=0 though (flags are in the upper bits of the first argument; the lower bits are the signal to be generated on exit). As far as I can tell, this is the correct way to use clone to provide fork. > > int select(int n, fd_set *restrict rfds, fd_set *restrict wfds, fd_set *restrict efds, struct timeval *restrict tv) > > { > > +#ifdef SYS_select > > return syscall_cp(SYS_select, n, rfds, wfds, efds, tv); > > +#else > > + long data[2] = { 0, _NSIG/8 }; > > + struct timespec ts; > > + if (tv) { > > + ts.tv_sec = tv->tv_sec; > > + ts.tv_nsec = tv->tv_usec > 999999 ? > > + 999999999 : tv->tv_usec * 1000; > > + } > > + return syscall_cp(SYS_pselect6, n, rfds, wfds, efds, tv ? &ts : 0, data); > > +#endif > > tv_usec may be negative Then the kernel should generate the EINVAL for us. > isnt it better to adjust tv_sec if usec is large? > or fail with EINVAL like in futimensat: POSIX allows implementation-defined limits on the duration, but now that you say it, what I wrote above is not not a correct implementation of such a limit. I'm not clear on whether we should renormalize into timespec or just reject out-of-range usec values; unlike in some other places where timespec is used, POSIX is missing text on select and pselect regarding how out-of-range timespec and timeval structs should be handled... > > pid_t getpgrp(void) > > { > > +#ifdef SYS_getpgrp > > return __syscall(SYS_getpgrp); > > +#else > > + return __syscall(SYS_getpgid, 0); > > +#endif > > you said this can be just the new call Ah yes, I forgot to change that. Rich