From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: [PATCH v4 1/5] setup: add gentle version of read_gitfile Date: Sat, 25 Apr 2015 09:51:45 -0700 Message-ID: References: <1429952801-2646-1-git-send-email-erik.elfstrom@gmail.com> <1429952801-2646-2-git-send-email-erik.elfstrom@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: git@vger.kernel.org To: Erik =?utf-8?Q?Elfstr=C3=B6m?= X-From: git-owner@vger.kernel.org Sat Apr 25 18:51:56 2015 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 1Ym3J5-0002ui-Ix for gcvg-git-2@plane.gmane.org; Sat, 25 Apr 2015 18:51:55 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753460AbbDYQvu convert rfc822-to-quoted-printable (ORCPT ); Sat, 25 Apr 2015 12:51:50 -0400 Received: from pb-smtp1.int.icgroup.com ([208.72.237.35]:52464 "EHLO sasl.smtp.pobox.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S964956AbbDYQvt convert rfc822-to-8bit (ORCPT ); Sat, 25 Apr 2015 12:51:49 -0400 Received: from sasl.smtp.pobox.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id E591B4996E; Sat, 25 Apr 2015 12:51:47 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type:content-transfer-encoding; s=sasl; bh=rwENq+gzkm2w 38vgNZEVTO5qwvI=; b=RP56XQyiXlNoLBG12Z9/3yYb6jIuK5Qd5kDWGpOdczlj f4s0jbRSAOPdrUyGXZHEfRWxwRtRVLtnT54/O1mjfTY5jTXnneKrQuYXEGRHE2Jo Kmq8ORr8co4TUHtj8aGDOO0pzypFM9bOM9WXz8EAfEKh2AC92E2Z+o3QB0Bt7k4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type:content-transfer-encoding; q=dns; s=sasl; b=xqpFNP kdD1FMB3FciA6wK0zXxMxRNv2stWRaJ/S3tsnGnO80q6iakFsjXwh2QLLofQIY8P zDIsBjUhVJyhcxU9u4tKlXUAvT9gdJUyJ/kE8WqgB/dDSDuGFi8tix/OoW9gpgE7 p3/wKCFo6G1izkkOzSNHU/dkT+jK2t4QDyE6I= Received: from pb-smtp1.int.icgroup.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id DDD8E4996D; Sat, 25 Apr 2015 12:51:47 -0400 (EDT) Received: from pobox.com (unknown [72.14.226.9]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by pb-smtp1.pobox.com (Postfix) with ESMTPSA id 3309B4996C; Sat, 25 Apr 2015 12:51:47 -0400 (EDT) In-Reply-To: <1429952801-2646-2-git-send-email-erik.elfstrom@gmail.com> ("Erik =?utf-8?Q?Elfstr=C3=B6m=22's?= message of "Sat, 25 Apr 2015 11:06:37 +0200") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) X-Pobox-Relay-ID: 5C670CDE-EB6B-11E4-86D6-83E09F42C9D4-77302942!pb-smtp1.pobox.com Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Erik Elfstr=C3=B6m writes: > read_gitfile will die on most error cases. This makes it unsuitable > for speculative calls. Extract the core logic and provide a gentle > version that returns NULL on failure. > > The first usecase of the new gentle version will be to probe for > submodules during git clean. > > Helped-by: Junio C Hamano > Helped-by: Jeff King > Signed-off-by: Erik Elfstr=C3=B6m > --- > cache.h | 3 ++- > setup.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++----= ---------- > 2 files changed, 67 insertions(+), 18 deletions(-) > > diff --git a/cache.h b/cache.h > index 3d3244b..6e29068 100644 > --- a/cache.h > +++ b/cache.h > @@ -431,7 +431,8 @@ extern int set_git_dir(const char *path); > extern const char *get_git_namespace(void); > extern const char *strip_namespace(const char *namespaced_ref); > extern const char *get_git_work_tree(void); > -extern const char *read_gitfile(const char *path); > +extern const char *read_gitfile_gently(const char *path, int *return= _error_code); > +#define read_gitfile(path) read_gitfile_gently((path), NULL) > extern const char *resolve_gitdir(const char *suspect); > extern void set_git_work_tree(const char *tree); > =20 > diff --git a/setup.c b/setup.c > index 979b13f..e1897cc 100644 > --- a/setup.c > +++ b/setup.c > @@ -335,35 +335,53 @@ static int check_repository_format_gently(const= char *gitdir, int *nongit_ok) > /* > * Try to read the location of the git directory from the .git file, > * return path to git directory if found. > + * > + * On failure, if return_error_code is not NULL, return_error_code > + * will be set to an error code and NULL will be returned. If > + * return_error_code is NULL the function will die instead (for most > + * cases). > */ > -const char *read_gitfile(const char *path) > +const char *read_gitfile_gently(const char *path, int *return_error_= code) > { > - char *buf; > - char *dir; > + int error_code =3D 0; > + char *buf =3D NULL; > + char *dir =3D NULL; > const char *slash; > struct stat st; > int fd; > ssize_t len; > =20 > - if (stat(path, &st)) > - return NULL; > - if (!S_ISREG(st.st_mode)) > - return NULL; > + if (stat(path, &st)) { > + error_code =3D 1; > + goto cleanup_return; > + } > + if (!S_ISREG(st.st_mode)) { > + error_code =3D 2; > + goto cleanup_return; > + } > fd =3D open(path, O_RDONLY); > - if (fd < 0) > - die_errno("Error opening '%s'", path); > + if (fd < 0) { > + error_code =3D 3; > + goto cleanup_return; > + } > buf =3D xmalloc(st.st_size + 1); > len =3D read_in_full(fd, buf, st.st_size); > close(fd); > - if (len !=3D st.st_size) > - die("Error reading %s", path); > + if (len !=3D st.st_size) { > + error_code =3D 4; > + goto cleanup_return; > + } > buf[len] =3D '\0'; > - if (!starts_with(buf, "gitdir: ")) > - die("Invalid gitfile format: %s", path); > + if (!starts_with(buf, "gitdir: ")) { > + error_code =3D 5; > + goto cleanup_return; > + } > while (buf[len - 1] =3D=3D '\n' || buf[len - 1] =3D=3D '\r') > len--; > - if (len < 9) > - die("No path in gitfile: %s", path); > + if (len < 9) { > + error_code =3D 6; > + goto cleanup_return; > + } > buf[len] =3D '\0'; > dir =3D buf + 8; > =20 > @@ -378,11 +396,41 @@ const char *read_gitfile(const char *path) > buf =3D dir; > } > =20 > - if (!is_git_directory(dir)) > - die("Not a git repository: %s", dir); > + if (!is_git_directory(dir)) { > + error_code =3D 7; > + goto cleanup_return; > + } > path =3D real_path(dir); > =20 > +cleanup_return: > free(buf); > + > + if (return_error_code) > + *return_error_code =3D error_code; > + > + if (error_code) { > + if (return_error_code) > + return NULL; > + > + switch (error_code) { > + case 1: // failed to stat > + case 2: // not regular file Please do not use C++ // comments. > + return NULL; > + case 3: > + die_errno("Error opening '%s'", path); > + case 4: > + die("Error reading %s", path); > + case 5: > + die("Invalid gitfile format: %s", path); > + case 6: > + die("No path in gitfile: %s", path); > + case 7: > + die("Not a git repository: %s", dir); > + default: > + assert(0); > + } > + } > + > return path; > }