From mboxrd@z Thu Jan 1 00:00:00 1970 From: Drew Northup Subject: Re: [PATCH] TIG: Implement mkstemps() work-around for platforms lacking it Date: Thu, 18 Jul 2013 00:45:23 -0400 Message-ID: <51E772E3.20008@gmail.com> References: <1373383992-4298-1-git-send-email-n1xim.email@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: git@vger.kernel.org, David Aguilar , Junio C Hamano , Johannes Sixt , Jonas Fonseca To: Drew Northup X-From: git-owner@vger.kernel.org Thu Jul 18 06:52:11 2013 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1UzgCI-0006nK-FB for gcvg-git-2@plane.gmane.org; Thu, 18 Jul 2013 06:52:10 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751302Ab3GREvt (ORCPT ); Thu, 18 Jul 2013 00:51:49 -0400 Received: from mail-ye0-f180.google.com ([209.85.213.180]:45342 "EHLO mail-ye0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751273Ab3GREvs (ORCPT ); Thu, 18 Jul 2013 00:51:48 -0400 Received: by mail-ye0-f180.google.com with SMTP id r11so813771yen.25 for ; Wed, 17 Jul 2013 21:51:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=yLr/8UOUm1O6u2yAPPP/1o3+wXleRKicB8zW9xruXH4=; b=G1L1puok8a9KdR1QSQMWNVCbZ5fTT1aL7hedB/nGbbXj1pK/PKOq1IZd55hI29BUHY Y8ikOT+FQsHZFqZcSPD7okZYMFOMjTAsFyHCKECKbuYVOeDHUDDotFjLlMIzCb3F7ogl fk8W7Tet9XyRgPKg2oTy5dc3bjoufiqYq9QaF1XxUoGZalsJLCWBgCVG2N8m7kY2/0to fgXRRF7FA/vshyQ5LFWr9RySrTuT5B8JUKV93phu3WOp2CanjQQzHtJHZ73Thu85VpyW 71DbD5LVoZNAquMItS2u21R/0IZ4f6Y3usqFtB1P3a/8PO4Mh/vBgl3PslvJ5u1Bc0q9 RZ5Q== X-Received: by 10.236.72.165 with SMTP id t25mr4644115yhd.47.1374122726761; Wed, 17 Jul 2013 21:45:26 -0700 (PDT) Received: from [192.168.0.37] (pool-70-16-105-6.port.east.myfairpoint.net. [70.16.105.6]) by mx.google.com with ESMTPSA id v32sm12660920yhc.12.2013.07.17.21.45.25 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 17 Jul 2013 21:45:26 -0700 (PDT) User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.28) Gecko/20120314 Thunderbird/3.1.20 In-Reply-To: <1373383992-4298-1-git-send-email-n1xim.email@gmail.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Giving this one last kick to make absolutely sure that nobody disagrees with allowing this code to be included into tig, which does not limit to a specific version of the GPL (version 2 in the case of git, any version equal to or newer than 2 in the case of tig), pursuant to paragraph 9 of said license. On 07/09/2013 11:33 AM, Drew Northup wrote: > The function mkstemps() isn't available in all libc implementations. In > glibc it first became available in 2.11, so platforms such as RHEL 5& > Slackware 13 lack it. This is likely true of many non-LINUX platforms > as well. > > This fixes breakage that was introduced with a0fdac29 "Create temporary > file with name as suffix." > > Signed-off-by: Drew Northup > --- > > This work-around is taken from Git and was inspired by code in libiberty. > It is presumed that this isn't a problem due to compatible license terms. > > A (virtually identical) version of this available in > https://github.com/n1xim/tig/tree/mkstemps_wkarnd (differences only in > the commit message). > > configure.ac | 4 ++++ > io.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > io.h | 14 +++++++++++ > 3 files changed, 95 insertions(+) > > diff --git a/configure.ac b/configure.ac > index 8dd2508..40e1f85 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -21,6 +21,10 @@ AC_SUBST(CURSES_LIB) > > AM_ICONV > > +dnl Not all platforms have mkstemps > +AC_CHECK_FUNC([mkstemps], [AC_DEFINE([HAVE_MKSTEMPS], [1], > + [Define if mkstemps is available.])]) > + > AC_PROG_CC > > AC_CHECK_PROGS(ASCIIDOC, [asciidoc], [false]) > diff --git a/io.c b/io.c > index 3ff1d1c..f1b6fbc 100644 > --- a/io.c > +++ b/io.c > @@ -237,6 +237,83 @@ encoding_convert(struct encoding *encoding, char *line) > } > > /* > + * Compatibility: no mkstemps() > + */ > + > +/* Adapted from libiberty's mkstemp.c via Git's wrapper.c. */ > + > +#undef TMP_MAX > +#define TMP_MAX 16384 > + > +int tig_mkstemps_mode(char *pattern, int suffix_len, int mode) > +{ > + static const char letters[] = > + "abcdefghijklmnopqrstuvwxyz" > + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" > + "0123456789"; > + static const int num_letters = 62; > + uint64_t value; > + struct timeval tv; > + char *template; > + size_t len; > + int fd, count; > + > + len = strlen(pattern); > + > + if (len< 6 + suffix_len) { > + errno = EINVAL; > + return -1; > + } > + > + if (strncmp(&pattern[len - 6 - suffix_len], "XXXXXX", 6)) { > + errno = EINVAL; > + return -1; > + } > + > + /* > + * Replace pattern's XXXXXX characters with randomness. > + * Try TMP_MAX different filenames. > + */ > + gettimeofday(&tv, NULL); > + value = ((size_t)(tv.tv_usec<< 16)) ^ tv.tv_sec ^ getpid(); > + template =&pattern[len - 6 - suffix_len]; > + for (count = 0; count< TMP_MAX; ++count) { > + uint64_t v = value; > + /* Fill in the random bits. */ > + template[0] = letters[v % num_letters]; v /= num_letters; > + template[1] = letters[v % num_letters]; v /= num_letters; > + template[2] = letters[v % num_letters]; v /= num_letters; > + template[3] = letters[v % num_letters]; v /= num_letters; > + template[4] = letters[v % num_letters]; v /= num_letters; > + template[5] = letters[v % num_letters]; v /= num_letters; > + > + fd = open(pattern, O_CREAT | O_EXCL | O_RDWR, mode); > + if (fd> 0) > + return fd; > + /* > + * Fatal error (EPERM, ENOSPC etc). > + * It doesn't make sense to loop. > + */ > + if (errno != EEXIST) > + break; > + /* > + * This is a random value. It is only necessary that > + * the next TMP_MAX values generated by adding 7777 to > + * VALUE are different with (module 2^32). > + */ > + value += 7777; > + } > + /* We return the null string if we can't find a unique file name. */ > + pattern[0] = '\0'; > + return -1; > +} > + > +int tigmkstemps(char *pattern, int suffix_len) > +{ > + return tig_mkstemps_mode(pattern, suffix_len, 0600); > +} > + > +/* > * Executing external commands. > */ > > diff --git a/io.h b/io.h > index 646989d..8f43216 100644 > --- a/io.h > +++ b/io.h > @@ -16,6 +16,9 @@ > > #include "tig.h" > > +/* Needed for mkstemps workaround */ > +#include > + > /* > * Argument array helpers. > */ > @@ -41,6 +44,17 @@ struct encoding *encoding_open(const char *fromcode); > char *encoding_convert(struct encoding *encoding, char *line); > > /* > + * Compatibility: no mkstemps() > + */ > + > +#ifndef HAVE_MKSTEMPS > +#define mkstemps tigmkstemps > +#endif > + > +int tigmkstemps(char *, int); > +int tig_mkstemps_mode(char *pattern, int suffix_len, int mode); > + > +/* > * Executing external commands. > */ >