From patchwork Tue Jun 29 02:04:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Derrick Stolee X-Patchwork-Id: 12348837 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57E3FC11F64 for ; Tue, 29 Jun 2021 02:05:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 44CBD61CEB for ; Tue, 29 Jun 2021 02:05:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231700AbhF2CHe (ORCPT ); Mon, 28 Jun 2021 22:07:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231304AbhF2CH2 (ORCPT ); Mon, 28 Jun 2021 22:07:28 -0400 Received: from mail-wm1-x336.google.com (mail-wm1-x336.google.com [IPv6:2a00:1450:4864:20::336]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B415C061574 for ; Mon, 28 Jun 2021 19:05:01 -0700 (PDT) Received: by mail-wm1-x336.google.com with SMTP id l1so275235wme.4 for ; Mon, 28 Jun 2021 19:05:01 -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=dBg3vHNNCzcOWR2PJkKRKBYZUfvDuCHqFYdWYLOIH5Q=; b=t984QHVA52kowv+M/rMibnQvaXwAGNC6W0zd11JifSpwp8yEuxn8V27T9GqNSkwlST tmiEhZ4OWoc32FQiEZH5NZkIwzuvAiawd1l+IzRtN0igha5E9ygw0UvE4dSy+fCuHLqM bjiSZOgN80IXdzrz7uiKR5HuEnl/BoyBqdSyMbM5rM4btvA/+5EHaJ2rfnYpXILq9j9Y 3YjGcryE98CsZZX6V+f/O09aeu5jtll6lhqS3t5Kf9VDOZaebTXikvvCaCubeT2SETYF UZ1eu4Lu3WcxnqS3H9Xyij1Ol2dHdRsrs39jnITOdVyhep75l9CKVyMlaLfd15t9W2Qb fDzA== 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=dBg3vHNNCzcOWR2PJkKRKBYZUfvDuCHqFYdWYLOIH5Q=; b=Awf3czm3zt2qEVaopj1hHTFNHfzV21WDwLxFrlV9LoIRk8dXoy/obnRv8x9xTD38rV 4w+evYH3DyftK9bvbdj/nqREkbLEsP/f45Cg6Rn+DfkYMhXxoCBOZgxsMUvJkuIxkEkg jAIYphSzcgqd+/ynuGD+2vpQGl0tAVUJJX5HYZadAY8WmvPhW0TgVqO/K3w1ux3GYD0Q yqG9X0rcfL97M2ZSPaLZIHqFskcKFcg7tOUg+Jxa8G300r4s2JgYBQUVT6WoCe5D8TjA jf3XjtQjV7pE8V1MhCO7cPz0r0ELfMwym6jDkcWp0Ggjgs1RUqZ77JXgvdWWNPALDH7c y0wg== X-Gm-Message-State: AOAM533FBcQAtRP7zd/hx1awlSSlwkGvlWfk2AuZY+hCiMWp4q+sVyrq pt+wed0L2A6oWFYxD45ZA0fTJ81Hn5A= X-Google-Smtp-Source: ABdhPJwFTy+lXUASdiKxnO+sg7Xd8HeJSGXxPm1lp6X95Ix7i4iK1XIvwV/ImM1Y+3metfca24gDoQ== X-Received: by 2002:a7b:c44d:: with SMTP id l13mr29551434wmi.69.1624932300152; Mon, 28 Jun 2021 19:05:00 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id c12sm19335072wrr.90.2021.06.28.19.04.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Jun 2021 19:04:59 -0700 (PDT) Message-Id: <237ccf4e43dd461250b3e6d609a475c1d675ea86.1624932294.git.gitgitgadget@gmail.com> In-Reply-To: References: Date: Tue, 29 Jun 2021 02:04:46 +0000 Subject: [PATCH v7 09/16] unpack-trees: unpack sparse directory entries Fcc: Sent 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 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 | 105 +++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 97 insertions(+), 8 deletions(-) diff --git a/unpack-trees.c b/unpack-trees.c index d26386ce8b2..d141dffbd94 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 +1240,69 @@ 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 by at least one, hence "-2" here. + */ + pos = -pos - 2; + + if (pos < 0 || pos >= o->src_index->cache_nr) return NULL; + + /* + * We might have multiple entries between 'pos' and + * the actual sparse-directory entry, so start walking + * back until finding it or passing where it would be. + */ + 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 +1337,21 @@ 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 +1438,12 @@ 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; }