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: AS53758 23.128.96.0/24 X-Spam-Status: No, score=-3.7 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id 4488A1FB06 for ; Mon, 12 Jul 2021 17:56:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235841AbhGLR7A (ORCPT ); Mon, 12 Jul 2021 13:59:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48126 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235771AbhGLR6x (ORCPT ); Mon, 12 Jul 2021 13:58:53 -0400 Received: from mail-wr1-x430.google.com (mail-wr1-x430.google.com [IPv6:2a00:1450:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3B94FC0613E5 for ; Mon, 12 Jul 2021 10:56:05 -0700 (PDT) Received: by mail-wr1-x430.google.com with SMTP id r11so21535582wro.9 for ; Mon, 12 Jul 2021 10:56:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=/UNBWPl4t+GAChOB0nnPFbEBS+JT3xS246iyyM1PiPc=; b=eC0F/VZYOno0LO4GCcfVz7p0+ShlSmWNpAKj/nX31/KRXDXu4yGfw1w+/iRAVvXNZk FZp3deJeZh5W3hxNWW14X+zTRDtoLzcBx2vkgFP4iBEIo+uTsIUlOtWxA/dtOirjuVh1 jhh9ocqWGL/BzRAVWmN4GqzdMH5/USQuI+Cj9O6ntC5Uk6sEtJfzRZQL2CjWVETQv1KY pegbnXcHH/iExjahf52tCs8DXaRYj070aPJdszabe/xkb3ptQh9EOxvIaQ0TLdsuj6p9 w0XDUc0gI0a/jwEr35y6n59SYgYCcO6VHFsU2q+r1tl9j1i1te8TsqmWOVcsqsbEVQnW XeKQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=/UNBWPl4t+GAChOB0nnPFbEBS+JT3xS246iyyM1PiPc=; b=dQKLNRBReQI4kRP9/5MC2aBFBzc1fj1XJYZue/aQE2rz2tp6UbfHUAumVLRj0N+gz4 aRgU7Tx5R1DRH5ZHPWyBtP9ZhtEywfaHFTbO4T7voF6ofLScH7BmYVhjl+c5oFgRkZC6 dorDRCZyPc6DrHEawBC6HXeZ9a+VoWnxx19pI31dQGs/wCWH+vQ+eURlZT/Y0Yi7blFp XW0L4wGFnw4G0Io1KnkLH7cx8PUEKSk9MjjqadlEMkHFR8c8XeuEEenPwALeZwuzodRK GTyVYqwzd6CNZA7e8Zp/ACbBAZ+908w3sSVMdoFGN1kjepYe7C/oHzH7HWxK8WRUrBmJ EAMg== X-Gm-Message-State: AOAM533u39ErTkmNc9iK6EgCSBaFN7j4IIJezS//UCJqnU0bj5fyyOAv obH9axvVQck4mh5XRFCr/kh9FAywPhc= X-Google-Smtp-Source: ABdhPJzHgzNqPQAMqDYu/ZfYqVPamHTb0AsqLLDZd/eoCT+ue4xQs3Sg5X3KTQ2s16UjGfgetBIXDw== X-Received: by 2002:a05:6000:1a87:: with SMTP id f7mr252739wry.172.1626112563852; Mon, 12 Jul 2021 10:56:03 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id d18sm378656wmp.46.2021.07.12.10.56.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 Jul 2021 10:56:03 -0700 (PDT) Message-Id: In-Reply-To: References: From: "Derrick Stolee via GitGitGadget" Date: Mon, 12 Jul 2021 17:55:50 +0000 Subject: [PATCH v8 09/15] unpack-trees: unpack sparse directory entries Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: gitster@pobox.com, newren@gmail.com, Matheus Tavares Bernardino , Derrick Stolee , git@jeffhostetler.com, johannes.schindelin@gmx.de, Derrick Stolee , Derrick Stolee Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Derrick Stolee During unpack_callback(), index entries are compared against tree entries. These are matched according to names and types. One goal is to decide if we should recurse into subtrees or simply operate on one index entry. In the case of a sparse-directory entry, we do not want to recurse into that subtree and instead simply compare the trees. In some cases, we might want to perform a merge operation on the entry, such as during 'git checkout ' which wants to replace a sparse tree entry with the tree for that path at the target commit. We extend the logic within unpack_single_entry() to create a sparse-directory entry in this case, and then that is sent to call_unpack_fn(). There are some subtleties in this process. For instance, we need to update find_cache_entry() to allow finding a sparse-directory entry that exactly matches a given path. Use the new helper method sparse_dir_matches_path() for this. We also need to ignore conflict markers in the case that the entries correspond to directories and we already have a sparse directory entry. Signed-off-by: Derrick Stolee --- unpack-trees.c | 107 +++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 99 insertions(+), 8 deletions(-) diff --git a/unpack-trees.c b/unpack-trees.c index d26386ce8b2..62ccd5a0ff6 100644 --- a/unpack-trees.c +++ b/unpack-trees.c @@ -1052,13 +1052,15 @@ static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage, struct index_state *istate, - int is_transient) + int is_transient, + int is_sparse_directory) { size_t len = traverse_path_len(info, tree_entry_len(n)); + size_t alloc_len = is_sparse_directory ? len + 1 : len; struct cache_entry *ce = is_transient ? - make_empty_transient_cache_entry(len, NULL) : - make_empty_cache_entry(istate, len); + make_empty_transient_cache_entry(alloc_len, NULL) : + make_empty_cache_entry(istate, alloc_len); ce->ce_mode = create_ce_mode(n->mode); ce->ce_flags = create_ce_flags(stage); @@ -1067,6 +1069,13 @@ static struct cache_entry *create_ce_entry(const struct traverse_info *info, /* len+1 because the cache_entry allocates space for NUL */ make_traverse_path(ce->name, len + 1, info, n->path, n->pathlen); + if (is_sparse_directory) { + ce->name[len] = '/'; + ce->name[len + 1] = '\0'; + ce->ce_namelen++; + ce->ce_flags |= CE_SKIP_WORKTREE; + } + return ce; } @@ -1085,10 +1094,17 @@ static int unpack_single_entry(int n, unsigned long mask, struct unpack_trees_options *o = info->data; unsigned long conflicts = info->df_conflicts | dirmask; - /* Do we have *only* directories? Nothing to do */ if (mask == dirmask && !src[0]) return 0; + /* + * When we have a sparse directory entry for src[0], + * then this isn't necessarily a directory-file conflict. + */ + if (mask == dirmask && src[0] && + S_ISSPARSEDIR(src[0]->ce_mode)) + conflicts = 0; + /* * Ok, we've filled in up to any potential index entry in src[0], * now do the rest. @@ -1118,7 +1134,9 @@ static int unpack_single_entry(int n, unsigned long mask, * not stored in the index. otherwise construct the * cache entry from the index aware logic. */ - src[i + o->merge] = create_ce_entry(info, names + i, stage, &o->result, o->merge); + src[i + o->merge] = create_ce_entry(info, names + i, stage, + &o->result, o->merge, + bit & dirmask); } if (o->merge) { @@ -1222,16 +1240,71 @@ static int find_cache_pos(struct traverse_info *info, return -1; } +/* + * Given a sparse directory entry 'ce', compare ce->name to + * info->name + '/' + p->path + '/' if info->name is non-empty. + * Compare ce->name to p->path + '/' otherwise. Note that + * ce->name must end in a trailing '/' because it is a sparse + * directory entry. + */ +static int sparse_dir_matches_path(const struct cache_entry *ce, + struct traverse_info *info, + const struct name_entry *p) +{ + assert(S_ISSPARSEDIR(ce->ce_mode)); + assert(ce->name[ce->ce_namelen - 1] == '/'); + + if (info->namelen) + return ce->ce_namelen == info->namelen + p->pathlen + 2 && + ce->name[info->namelen] == '/' && + !strncmp(ce->name, info->name, info->namelen) && + !strncmp(ce->name + info->namelen + 1, p->path, p->pathlen); + return ce->ce_namelen == p->pathlen + 1 && + !strncmp(ce->name, p->path, p->pathlen); +} + static struct cache_entry *find_cache_entry(struct traverse_info *info, const struct name_entry *p) { + struct cache_entry *ce; int pos = find_cache_pos(info, p->path, p->pathlen); struct unpack_trees_options *o = info->data; if (0 <= pos) return o->src_index->cache[pos]; - else + + /* + * Check for a sparse-directory entry named "path/". + * Due to the input p->path not having a trailing + * slash, the negative 'pos' value overshoots the + * expected position, hence "-2" instead of "-1". + */ + pos = -pos - 2; + + if (pos < 0 || pos >= o->src_index->cache_nr) return NULL; + + /* + * Due to lexicographic sorting and sparse directory + * entried ending with a trailing slash, our path as a + * sparse directory (e.g "subdir/") and our path as a + * file (e.g. "subdir") might be separated by other + * paths (e.g. "subdir-"). + */ + while (pos >= 0) { + ce = o->src_index->cache[pos]; + + if (strncmp(ce->name, p->path, p->pathlen)) + return NULL; + + if (S_ISSPARSEDIR(ce->ce_mode) && + sparse_dir_matches_path(ce, info, p)) + return ce; + + pos--; + } + + return NULL; } static void debug_path(struct traverse_info *info) @@ -1266,6 +1339,21 @@ static void debug_unpack_callback(int n, debug_name_entry(i, names + i); } +/* + * Returns true if and only if the given cache_entry is a + * sparse-directory entry that matches the given name_entry + * from the tree walk at the given traverse_info. + */ +static int is_sparse_directory_entry(struct cache_entry *ce, + struct name_entry *name, + struct traverse_info *info) +{ + if (!ce || !name || !S_ISSPARSEDIR(ce->ce_mode)) + return 0; + + return sparse_dir_matches_path(ce, info, name); +} + /* * Note that traverse_by_cache_tree() duplicates some logic in this function * without actually calling it. If you change the logic here you may need to @@ -1352,9 +1440,12 @@ static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, str } } - if (traverse_trees_recursive(n, dirmask, mask & ~dirmask, - names, info) < 0) + if (!is_sparse_directory_entry(src[0], names, info) && + traverse_trees_recursive(n, dirmask, mask & ~dirmask, + names, info) < 0) { return -1; + } + return mask; } -- gitgitgadget