From owner-freebsd-arch@FreeBSD.ORG Sun Apr 19 08:52:55 2015 Return-Path: Delivered-To: arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 5AB4ED9C; Sun, 19 Apr 2015 08:52:55 +0000 (UTC) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id D6490CE8; Sun, 19 Apr 2015 08:52:54 +0000 (UTC) Received: from tom.home (kostik@localhost [127.0.0.1]) by kib.kiev.ua (8.14.9/8.14.9) with ESMTP id t3J8qn2N056851 (version=TLSv1/SSLv3 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO); Sun, 19 Apr 2015 11:52:49 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.9.2 kib.kiev.ua t3J8qn2N056851 Received: (from kostik@localhost) by tom.home (8.14.9/8.14.9/Submit) id t3J8qnSl056850; Sun, 19 Apr 2015 11:52:49 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Sun, 19 Apr 2015 11:52:48 +0300 From: Konstantin Belousov To: Oliver Pinter Cc: "freebsd-arch@freebsd.org" , peter@freebsd.org Subject: setproctitle [was: Re: Removal of the 6.x kernel compat code from libc] Message-ID: <20150419085248.GB2390@kib.kiev.ua> References: <20150417075942.GI2390@kib.kiev.ua> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.0 X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on tom.home X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 19 Apr 2015 08:52:55 -0000 On Fri, Apr 17, 2015 at 01:39:04PM +0200, Oliver Pinter wrote: > Is there any chanche to get ride of the very old (FreeBSD 2.x) compat > hacks like these: > https://github.com/freebsd/freebsd/blob/master/lib/libc/gen/setproctitle.c#L40 ? > Below is the promised cleanup of the libc/gen/setproctitle.c. I see a value in keeping the track of the historical interfaces. I considered moving the explanation about old_ps_strings to sys/exec.h, where the current ps_strings is defined and explained, but this would make the safety checks in the setproctitle() code uncomprehensive. diff --git a/lib/libc/gen/setproctitle.c b/lib/libc/gen/setproctitle.c index cd705fb..9dff328 100644 --- a/lib/libc/gen/setproctitle.c +++ b/lib/libc/gen/setproctitle.c @@ -42,9 +42,10 @@ __FBSDID("$FreeBSD$"); * 1: old_ps_strings at the very top of the stack. * 2: old_ps_strings at SPARE_USRSPACE below the top of the stack. * 3: ps_strings at the very top of the stack. - * This attempts to support a kernel built in the #2 and #3 era. - */ - + * We only support a kernel providing #3 style ps_strings. + * + * For historical purposes, a definition of the old ps_strings structure + * and location is preserved below: struct old_ps_strings { char *old_ps_argvstr; int old_ps_nargvstr; @@ -53,6 +54,7 @@ struct old_ps_strings { }; #define OLD_PS_STRINGS ((struct old_ps_strings *) \ (USRSTACK - SPARE_USRSPACE - sizeof(struct old_ps_strings))) + */ #include @@ -136,41 +138,38 @@ setproctitle(const char *fmt, ...) ps_strings = (struct ps_strings *)ul_ps_strings; } - /* PS_STRINGS points to zeroed memory on a style #2 kernel */ - if (ps_strings->ps_argvstr) { - /* style #3 */ - if (oargc == -1) { - /* Record our original args */ - oargc = ps_strings->ps_nargvstr; - oargv = ps_strings->ps_argvstr; - for (i = len = 0; i < oargc; i++) { - /* - * The program may have scribbled into its - * argv array, e.g., to remove some arguments. - * If that has happened, break out before - * trying to call strlen on a NULL pointer. - */ - if (oargv[i] == NULL) { - oargc = i; - break; - } - snprintf(obuf + len, SPT_BUFSIZE - len, "%s%s", - len ? " " : "", oargv[i]); - if (len) - len++; - len += strlen(oargv[i]); - if (len >= SPT_BUFSIZE) - break; + /* + * PS_STRINGS points to zeroed memory on a style #2 kernel. + * Should not happen. + */ + if (ps_strings->ps_argvstr == NULL) + return; + + /* style #3 */ + if (oargc == -1) { + /* Record our original args */ + oargc = ps_strings->ps_nargvstr; + oargv = ps_strings->ps_argvstr; + for (i = len = 0; i < oargc; i++) { + /* + * The program may have scribbled into its + * argv array, e.g., to remove some arguments. + * If that has happened, break out before + * trying to call strlen on a NULL pointer. + */ + if (oargv[i] == NULL) { + oargc = i; + break; } + snprintf(obuf + len, SPT_BUFSIZE - len, "%s%s", + len != 0 ? " " : "", oargv[i]); + if (len != 0) + len++; + len += strlen(oargv[i]); + if (len >= SPT_BUFSIZE) + break; } - ps_strings->ps_nargvstr = nargc; - ps_strings->ps_argvstr = nargvp; - } else { - /* style #2 - we can only restore our first arg :-( */ - if (*obuf == '\0') - strncpy(obuf, OLD_PS_STRINGS->old_ps_argvstr, - SPT_BUFSIZE - 1); - OLD_PS_STRINGS->old_ps_nargvstr = 1; - OLD_PS_STRINGS->old_ps_argvstr = nargvp[0]; } + ps_strings->ps_nargvstr = nargc; + ps_strings->ps_argvstr = nargvp; }