From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x227DrpgOByXSaEfVbUJU9arzNyhHdN4eh4Ep+6EYlDhL8w4Dt+YbXHpVOxCIpMOs0uUGiuoj ARC-Seal: i=1; a=rsa-sha256; t=1516827253; cv=none; d=google.com; s=arc-20160816; b=02xUwzlmQTo7hMey+h4KSfcVxZiJC8fFcI3MueG7BN6VujHr4h3yFBk3NMfRCEYuv5 sIXlvJgeik9l5NL8YVF4Meg2DHV1zig6G8SLPAZbhlBjiquw0/cOz4BznfssBx2Zk2i2 XbGhkz7qs0pOlzkmF3gm5boHaAwd4csKDElL9bP0yJgtu0a8XwMhbAGmLHD7v0U5Lr+7 CMFMOHDtJJ/uHY7vQvZCEwclPVKnqyaxqs/YN+SScXREbeV0lLlxlxyZE5fmgIrte/LS gcSFy0haLbpsDbfHPt/BGxu/Ic2hBVjxWJrht/SKEsJNKUqT6MPCs+DeYy1sEDTMqz3g +A/A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:arc-authentication-results; bh=JuDxv6QsfLjSMvTS53osqHOy/TkO66QGRA9/oxJBknw=; b=TQzFI4nNQokAxyRaMB3cB6VRDJNuEaNdizWfnzhJkAbgB7Byx4hW0rIb7CXZHMeY4+ 7dDETkZ7kuXO+PlmzBtukwxOYBOyrTOnmL8b7/nCFz4oP6lVXBef+MjVWUlv4Jdy3p3X 2GQaCQxz7SJuLx83V9/oGq+LiqTAuPQ/0peYrGF1sfiyxJ8gytjUjzaqtE/rlm/goAZG cepe5Uh9Bz0nlX3Ci/2WC4JqBCNEbS6c+SvvgMnTVwPCBsi1n7lRLcqcNVmjTrjddEca g/dfoKAJwWkd9whLG+GcXp3zZvf3WiDzSNy78oGwgLzMZ8E/XlW+MRZFLJtRCpotyfer JJew== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of jpoimboe@redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=jpoimboe@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of jpoimboe@redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=jpoimboe@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Date: Wed, 24 Jan 2018 14:54:11 -0600 From: Josh Poimboeuf To: Arvind Sankar Cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo Subject: Re: [PATCH] tools: libsubcmd: Drop the less hack that was inherited from Git. Message-ID: <20180124205411.lpzcpqnuw3nlyg4n@treble> References: <20180124003831.GA34667@rani.riverdale> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180124003831.GA34667@rani.riverdale> User-Agent: Mutt/1.6.0.1 (2016-04-01) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1590432180841544172?= X-GMAIL-MSGID: =?utf-8?q?1590508653893244558?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Tue, Jan 23, 2018 at 07:38:37PM -0500, Arvind Sankar wrote: > We inherited this hack with the original code from the Git project. The > select call is invalid as the two fd_set pointers should not be aliased. > > We could fix it, but the Git project removed this hack in 2012 in commit > e8320f3 (pager: drop "wait for output to run less" hack). The bug it > worked around was apparently fixed in less back in June 2007. > > So remove the hack from here as well. > > Signed-off-by: Arvind Sankar Looks good to me. Acked-by: Josh Poimboeuf Libsubcmd is used by perf and objtool, so adding the perf maintainers to CC. Arnaldo, do you want to pick this one up? > --- > tools/lib/subcmd/pager.c | 17 ----------------- > tools/lib/subcmd/run-command.c | 2 -- > tools/lib/subcmd/run-command.h | 1 - > 3 files changed, 20 deletions(-) > > diff --git a/tools/lib/subcmd/pager.c b/tools/lib/subcmd/pager.c > index 5ba754d17952..94d61d9b511f 100644 > --- a/tools/lib/subcmd/pager.c > +++ b/tools/lib/subcmd/pager.c > @@ -1,5 +1,4 @@ > // SPDX-License-Identifier: GPL-2.0 > -#include > #include > #include > #include > @@ -23,21 +22,6 @@ void pager_init(const char *pager_env) > subcmd_config.pager_env = pager_env; > } > > -static void pager_preexec(void) > -{ > - /* > - * Work around bug in "less" by not starting it until we > - * have real input > - */ > - fd_set in; > - > - FD_ZERO(&in); > - FD_SET(0, &in); > - select(1, &in, NULL, &in, NULL); > - > - setenv("LESS", "FRSX", 0); > -} > - > static const char *pager_argv[] = { "sh", "-c", NULL, NULL }; > static struct child_process pager_process; > > @@ -84,7 +68,6 @@ void setup_pager(void) > pager_argv[2] = pager; > pager_process.argv = pager_argv; > pager_process.in = -1; > - pager_process.preexec_cb = pager_preexec; > > if (start_command(&pager_process)) > return; > diff --git a/tools/lib/subcmd/run-command.c b/tools/lib/subcmd/run-command.c > index 5cdac2162532..9e9dca717ed7 100644 > --- a/tools/lib/subcmd/run-command.c > +++ b/tools/lib/subcmd/run-command.c > @@ -120,8 +120,6 @@ int start_command(struct child_process *cmd) > unsetenv(*cmd->env); > } > } > - if (cmd->preexec_cb) > - cmd->preexec_cb(); > if (cmd->exec_cmd) { > execv_cmd(cmd->argv); > } else { > diff --git a/tools/lib/subcmd/run-command.h b/tools/lib/subcmd/run-command.h > index 17d969c6add3..6256268802b5 100644 > --- a/tools/lib/subcmd/run-command.h > +++ b/tools/lib/subcmd/run-command.h > @@ -46,7 +46,6 @@ struct child_process { > unsigned no_stderr:1; > unsigned exec_cmd:1; /* if this is to be external sub-command */ > unsigned stdout_to_stderr:1; > - void (*preexec_cb)(void); > }; > > int start_command(struct child_process *); > -- > 2.13.6 > -- Josh