From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kay Sievers Subject: Re: git and symlinks as tracked content Date: Thu, 5 May 2005 00:35:32 +0200 Message-ID: <20050504223532.GA22967@vrfy.org> References: <1115145234.21105.111.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: git@vger.kernel.org X-From: git-owner@vger.kernel.org Thu May 05 00:30:28 2005 Return-path: Received: from vger.kernel.org ([12.107.209.244]) by ciao.gmane.org with esmtp (Exim 4.43) id 1DTSNC-0008Ju-DJ for gcvg-git@gmane.org; Thu, 05 May 2005 00:29:42 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261935AbVEDWgG (ORCPT ); Wed, 4 May 2005 18:36:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261936AbVEDWgG (ORCPT ); Wed, 4 May 2005 18:36:06 -0400 Received: from soundwarez.org ([217.160.171.123]:47301 "EHLO soundwarez.org") by vger.kernel.org with ESMTP id S261935AbVEDWff (ORCPT ); Wed, 4 May 2005 18:35:35 -0400 Received: by soundwarez.org (Postfix, from userid 2702) id 55CAC2CD33; Thu, 5 May 2005 00:35:32 +0200 (CEST) To: Linus Torvalds Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.9i Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org On Tue, May 03, 2005 at 12:02:33PM -0700, Linus Torvalds wrote: > > > On Tue, 3 May 2005, Kay Sievers wrote: > > > > Is there a sane model to make git aware of tracking symlinks in the > > repository? In the bk udev tree we've had a test sysfs-tree with a lot > > of symlinks in it. > > > > Where can we store the link-target? In its own blob-object or directly > > in the tree-object? > > I'd suggest you create a blob object with the symlink name, and then in > the tree you point to that blob, but with the S_IFLNK value in the mode > field (0120000). > > So you have > > - directories: S_IFDIR (0040000) point to "tree" objects for contents > - symlinks: S_IFLNK (0120000) point to "blob" objects > - executables: S_IFREG | 0755 (0100755) point to "blob" objects > - regular files: S_IFREG | 0644 (0100644) point to "blob" objects > > which seems very sane and regular. Here is a first try, that is able to track symlinks. Please have a look if something like this is acceptable, then I will finish it. Thanks, Kay --- a/check-files.c +++ b/check-files.c @@ -28,8 +28,8 @@ static void check_file(const char *path) die("preparing to update existing file '%s' not in cache", path); ce = active_cache[pos]; - if (fstat(fd, &st) < 0) - die("fstat(%s): %s", path, strerror(errno)); + if (lstat(path, &st) < 0) + die("lstat(%s): %s", path, strerror(errno)); changed = cache_match_stat(ce, &st); if (changed) --- a/checkout-cache.c +++ b/checkout-cache.c @@ -72,23 +72,37 @@ static int write_entry(struct cache_entr unsigned long size; long wrote; char type[20]; + unsigned int mode; new = read_sha1_file(ce->sha1, type, &size); if (!new || strcmp(type, "blob")) { return error("checkout-cache: unable to read sha1 file of %s (%s)", path, sha1_to_hex(ce->sha1)); } - fd = create_file(path, ntohl(ce->ce_mode)); - if (fd < 0) { + mode = ntohl(ce->ce_mode); + if (S_ISLNK(mode)) { + char target[1024]; + memcpy(target, new, size); + target[size] = '\0'; + if (symlink(target, path)) { + free(new); + return error("checkout-cache: unable to create link %s (%s)", + path, strerror(errno)); + } + free(new); + } else { + fd = create_file(path, mode); + if (fd < 0) { + free(new); + return error("checkout-cache: unable to create file %s (%s)", + path, strerror(errno)); + } + wrote = write(fd, new, size); + close(fd); free(new); - return error("checkout-cache: unable to create %s (%s)", - path, strerror(errno)); + if (wrote != size) + return error("checkout-cache: unable to write %s", path); } - wrote = write(fd, new, size); - close(fd); - free(new); - if (wrote != size) - return error("checkout-cache: unable to write %s", path); return 0; } @@ -101,7 +115,7 @@ static int checkout_entry(struct cache_e memcpy(path, base_dir, len); strcpy(path + len, ce->name); - if (!stat(path, &st)) { + if (!lstat(path, &st)) { unsigned changed = cache_match_stat(ce, &st); if (!changed) return 0; --- a/diff-cache.c +++ b/diff-cache.c @@ -24,7 +24,7 @@ static int get_stat_data(struct cache_en static unsigned char no_sha1[20]; int changed; struct stat st; - if (stat(ce->name, &st) < 0) + if (lstat(ce->name, &st) < 0) return -1; changed = cache_match_stat(ce, &st); if (changed) { --- a/ls-files.c +++ b/ls-files.c @@ -199,7 +199,7 @@ static void show_files(void) struct stat st; if (excluded(ce->name) != show_ignored) continue; - if (!stat(ce->name, &st)) + if (!lstat(ce->name, &st)) continue; printf("%s%c", ce->name, line_terminator); } --- a/tree.c +++ b/tree.c @@ -13,7 +13,10 @@ static int read_one_entry(unsigned char memset(ce, 0, size); - ce->ce_mode = create_ce_mode(mode); + if (mode & S_IFMT) + ce->ce_mode = htonl(mode); + else + ce->ce_mode = create_ce_mode(mode); ce->ce_flags = create_ce_flags(baselen + len, stage); memcpy(ce->name, base, baselen); memcpy(ce->name + baselen, pathname, len+1); --- a/update-cache.c +++ b/update-cache.c @@ -58,30 +58,37 @@ static int add_file_to_cache(char *path) struct stat st; int fd; - fd = open(path, O_RDONLY); - if (fd < 0) { + if (lstat(path, &st) < 0) { if (errno == ENOENT || errno == ENOTDIR) { if (allow_remove) return remove_file_from_cache(path); } return -1; } - if (fstat(fd, &st) < 0) { - close(fd); - return -1; - } namelen = strlen(path); size = cache_entry_size(namelen); ce = xmalloc(size); memset(ce, 0, size); memcpy(ce->name, path, namelen); fill_stat_cache_info(ce, &st); - ce->ce_mode = create_ce_mode(st.st_mode); + if (S_ISREG(st.st_mode)) { + fd = open(path, O_RDONLY); + if (fd < 0) + return -1; + ce->ce_mode = create_ce_mode(st.st_mode); + if (index_fd(ce->sha1, fd, &st) < 0) + return -1; + } else if (S_ISLNK(st.st_mode)) { + unsigned int len; + char target[1024]; + ce->ce_mode = htonl(S_IFLNK); + len = readlink(path, target, sizeof(target)); + if (len == -1 || len+1 > sizeof(target)) + return -1; + if (write_sha1_file(target, len, "blob", ce->sha1)) + return -1; + } ce->ce_flags = htons(namelen); - - if (index_fd(ce->sha1, fd, &st) < 0) - return -1; - return add_cache_entry(ce, allow_add); } @@ -137,7 +144,7 @@ static struct cache_entry *refresh_entry struct cache_entry *updated; int changed, size; - if (stat(ce->name, &st) < 0) + if (lstat(ce->name, &st) < 0) return ERR_PTR(-errno); changed = cache_match_stat(ce, &st);