From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/10453 Path: news.gmane.org!.POSTED!not-for-mail From: Rich Felker Newsgroups: gmane.linux.lib.musl.general Subject: Re: [PATCH RFC] add pthread_setname_np Date: Wed, 14 Sep 2016 23:27:31 -0400 Message-ID: <20160915032731.GE15995@brightrain.aerifal.cx> References: <20160915030216.GA4535@nyan> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: blaine.gmane.org 1473910074 2111 195.159.176.226 (15 Sep 2016 03:27:54 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Thu, 15 Sep 2016 03:27:54 +0000 (UTC) User-Agent: Mutt/1.5.21 (2010-09-15) To: musl@lists.openwall.com Original-X-From: musl-return-10466-gllmg-musl=m.gmane.org@lists.openwall.com Thu Sep 15 05:27:50 2016 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by blaine.gmane.org with smtp (Exim 4.84_2) (envelope-from ) id 1bkNKz-00084o-UM for gllmg-musl@m.gmane.org; Thu, 15 Sep 2016 05:27:46 +0200 Original-Received: (qmail 29839 invoked by uid 550); 15 Sep 2016 03:27:45 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Original-Received: (qmail 29818 invoked from network); 15 Sep 2016 03:27:44 -0000 Content-Disposition: inline In-Reply-To: <20160915030216.GA4535@nyan> Original-Sender: Rich Felker Xref: news.gmane.org gmane.linux.lib.musl.general:10453 Archived-At: On Wed, Sep 14, 2016 at 11:02:16PM -0400, Felix Janda wrote: > gdb's "info threads" displays the thread name. > --- > Should this function care about interrupted syscalls? Unless it's specified not to return EINTR I'm fine with it returning EINTR. > --- > include/pthread.h | 1 + > src/thread/pthread_setname_np.c | 21 +++++++++++++++++++++ > 2 files changed, 22 insertions(+) > create mode 100644 src/thread/pthread_setname_np.c > > diff --git a/include/pthread.h b/include/pthread.h > index 3d2e0c4..94ef919 100644 > --- a/include/pthread.h > +++ b/include/pthread.h > @@ -214,6 +214,7 @@ struct cpu_set_t; > int pthread_getaffinity_np(pthread_t, size_t, struct cpu_set_t *); > int pthread_setaffinity_np(pthread_t, size_t, const struct cpu_set_t *); > int pthread_getattr_np(pthread_t, pthread_attr_t *); > +int pthread_setname_np(pthread_t, const char *); > int pthread_tryjoin_np(pthread_t, void **); > int pthread_timedjoin_np(pthread_t, void **, const struct timespec *); > #endif > diff --git a/src/thread/pthread_setname_np.c b/src/thread/pthread_setname_np.c > new file mode 100644 > index 0000000..b7f7a4b > --- /dev/null > +++ b/src/thread/pthread_setname_np.c > @@ -0,0 +1,21 @@ > +#include > +#include > +#include > + > +#include "pthread_impl.h" > + > +int pthread_setname_np(pthread_t thread, const char *name) > +{ > + int fd, status = 0; > + char f[sizeof "/proc/self/task//comm" + 7]; Where does 7 come from? I don't think it's correct. 3*sizeof(int) is the normal lazy bound we use for %d's. > + ssize_t len; > + > + if ((len = strlen(name)) > 15) return ERANGE; Storing the result of strlen in a ssize_t is odd. It works because no object can be larger than SIZE_MAX/2, but it's ugly. Also using strnlen would be preferable if there's a limit (so as not to read unboundedly long strings only to reject them). > + > + snprintf(f, sizeof f, "/proc/self/task/%d/comm", thread->tid); > + if ((fd = open(f, O_WRONLY)) < 0) return errno; > + if (write(fd, name, len) < 0) status = errno; > + > + close(fd); This needs blocking of the cancellation points, I think. Rich