From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS3215 2.6.0.0/16 X-Spam-Status: No, score=-0.3 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from out1.vger.email (out1.vger.email [IPv6:2620:137:e000::1:20]) by dcvr.yhbt.net (Postfix) with ESMTP id CAB341F8C4 for ; Tue, 15 Mar 2022 17:51:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350746AbiCORwn (ORCPT ); Tue, 15 Mar 2022 13:52:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49646 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237757AbiCORwj (ORCPT ); Tue, 15 Mar 2022 13:52:39 -0400 Received: from pb-smtp20.pobox.com (pb-smtp20.pobox.com [173.228.157.52]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8266B51312 for ; Tue, 15 Mar 2022 10:51:26 -0700 (PDT) Received: from pb-smtp20.pobox.com (unknown [127.0.0.1]) by pb-smtp20.pobox.com (Postfix) with ESMTP id E633E19279B; Tue, 15 Mar 2022 13:51:25 -0400 (EDT) (envelope-from junio@pobox.com) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=sasl; bh=F3hshD/JFYxOLQ5MGbdfZcG3kdm+H1xMiDo9gM Aq5ms=; b=piGB3k+jyPDKVTlCOpWYjGMWMQaCFgxlLJ4hseCuTqXohswvGnknSh vVfp+Su5UUN0DEVb0yYGQPUtIIzbeChqJ8x/uq6JCFiffx+IrCBPgtzM+YOEszRX LHzpn6NhfRoJyNC26zhbxqUX0x1I2Fsz6RGfgsUStYcx2l+2fe4Gg= Received: from pb-smtp20.sea.icgroup.com (unknown [127.0.0.1]) by pb-smtp20.pobox.com (Postfix) with ESMTP id DEF4619279A; Tue, 15 Mar 2022 13:51:25 -0400 (EDT) (envelope-from junio@pobox.com) Received: from pobox.com (unknown [34.82.80.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by pb-smtp20.pobox.com (Postfix) with ESMTPSA id 26F63192797; Tue, 15 Mar 2022 13:51:22 -0400 (EDT) (envelope-from junio@pobox.com) From: Junio C Hamano To: Phillip Wood Cc: Git Mailing List , Phillip Wood , =?utf-8?B?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason , Carlo Arenas , Johannes Schindelin , Ramsay Jones Subject: Re: [PATCH v3 4/4] terminal: restore settings on SIGTSTP References: <20220304131126.8293-1-phillip.wood123@gmail.com> <20220315105723.19398-1-phillip.wood123@gmail.com> <20220315105723.19398-5-phillip.wood123@gmail.com> Date: Tue, 15 Mar 2022 10:51:21 -0700 In-Reply-To: <20220315105723.19398-5-phillip.wood123@gmail.com> (Phillip Wood's message of "Tue, 15 Mar 2022 10:57:23 +0000") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Pobox-Relay-ID: 8690C788-A488-11EC-BEF5-C85A9F429DF0-77302942!pb-smtp20.pobox.com Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Phillip Wood writes: > @@ -23,6 +23,101 @@ static void restore_term_on_signal(int sig) > static int term_fd = -1; > static struct termios old_term; > > +static const char *background_resume_msg; > +static const char *restore_error_msg; > +static volatile sig_atomic_t ttou_received; It is a good idea to have a comment here to say why we had to reinvent a subset of error(), instead of forcing curious readers to "git blame" the log message for this commit (I am assuming that "this is called from a signal handler and uses only functions that are safe in that context" is the reason). > +static void write_err(const char *msg) > +{ > + write_in_full(2, "error: ", strlen("error: ")); > + write_in_full(2, msg, strlen(msg)); > + write_in_full(2, "\n", 1); > +} > + > +static void print_background_resume_msg(int signo) > +{ > + int saved_errno = errno; > + sigset_t mask; > + struct sigaction old_sa; > + struct sigaction sa = { .sa_handler = SIG_DFL }; > + > + ttou_received = 1; > + write_err(background_resume_msg); > + sigaction(signo, &sa, &old_sa); > + raise(signo); > + sigemptyset(&mask); > + sigaddset(&mask, signo); > + sigprocmask(SIG_UNBLOCK, &mask, NULL); > + /* Stopped here */ > + sigprocmask(SIG_BLOCK, &mask, NULL); > + sigaction(signo, &old_sa, NULL); > + errno = saved_errno; > +} > ... > + /* avoid calling gettext() from signal handler */ > + background_resume_msg = _("cannot resume in the background, please use 'fg' to resume"); > + restore_error_msg = _("cannot restore terminal settings"); Nice to see such an attention to detail here. Thanks.