[PATCH v4 4/7] merge-ort: add a handle_deferred_entries() helper function

From: Elijah Newren via GitGitGadget <gitgitgadget@gmail.com>
Date: Jul 21, 2021, 04:24 UTC
Message-ID: <ff568a612f5559789326108d5fb6d7090a6a56b6.1626841444.git.gitgitgadget@gmail.com>
In-Reply-To: <pull.988.v4.git.1626841444.gitgitgadget@gmail.com>

From: Elijah Newren <newren@gmail.com>

In order to allow trivial directory resolution, we first need to be able to gather more information to determine if the optimization is safe. To enable that, we need a way of deferring the recursion into the directory until a later time. Naturally, deferring the entry into a subtree means that we need some function that will later recurse into the subdirectory exactly the same way that collect_merge_info_callback() would have done.

Add a helper function that does this. For now this function is not used but a subsequent commit will change that. Future commits will also make the function sometimes resolve directories instead of traversing inside.

Acked-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
---
 merge-ort.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/merge-ort.c b/merge-ort.c
index d9263ec5aca..f0a07684df6 100644
--- a/merge-ort.c
+++ b/merge-ort.c
@@ -1202,6 +1202,70 @@ static int collect_merge_info_callback(int n,
 	return mask;
 }
 
+MAYBE_UNUSED
+static int handle_deferred_entries(struct merge_options *opt,
+				   struct traverse_info *info)
+{
+	struct rename_info *renames = &opt->priv->renames;
+	struct hashmap_iter iter;
+	struct strmap_entry *entry;
+	int side, ret = 0;
+
+	for (side = MERGE_SIDE1; side <= MERGE_SIDE2; side++) {
+		renames->deferred[side].trivial_merges_okay = 0;
+		strintmap_for_each_entry(&renames->deferred[side].possible_trivial_merges,
+					 &iter, entry) {
+			const char *path = entry->key;
+			unsigned dir_rename_mask = (intptr_t)entry->value;
+			struct conflict_info *ci;
+			unsigned dirmask;
+			struct tree_desc t[3];
+			void *buf[3] = {NULL,};
+			int i;
+
+			ci = strmap_get(&opt->priv->paths, path);
+			VERIFY_CI(ci);
+			dirmask = ci->dirmask;
+
+			info->name = path;
+			info->namelen = strlen(path);
+			info->pathlen = info->namelen + 1;
+
+			for (i = 0; i < 3; i++, dirmask >>= 1) {
+				if (i == 1 && ci->match_mask == 3)
+					t[1] = t[0];
+				else if (i == 2 && ci->match_mask == 5)
+					t[2] = t[0];
+				else if (i == 2 && ci->match_mask == 6)
+					t[2] = t[1];
+				else {
+					const struct object_id *oid = NULL;
+					if (dirmask & 1)
+						oid = &ci->stages[i].oid;
+					buf[i] = fill_tree_descriptor(opt->repo,
+								      t+i, oid);
+				}
+			}
+
+			ci->match_mask &= ci->filemask;
+			opt->priv->current_dir_name = path;
+			renames->dir_rename_mask = dir_rename_mask;
+			if (renames->dir_rename_mask == 0 ||
+			    renames->dir_rename_mask == 0x07)
+				ret = traverse_trees(NULL, 3, t, info);
+			else
+				ret = traverse_trees_wrapper(NULL, 3, t, info);
+
+			for (i = MERGE_BASE; i <= MERGE_SIDE2; i++)
+				free(buf[i]);
+
+			if (ret < 0)
+				return ret;
+		}
+	}
+	return ret;
+}
+
 static int collect_merge_info(struct merge_options *opt,
 			      struct tree *merge_base,
 			      struct tree *side1,

-- 
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