[PATCH v2 3/8] merge-ort: add data structures for an alternate tree traversal

From: Elijah Newren via GitGitGadget <gitgitgadget@gmail.com>
Date: Mar 9, 2021, 00:09 UTC
Message-ID: <89b43c9f75a03ab8cc258db8e6a1137e6e6fbb3f.1615248599.git.gitgitgadget@gmail.com>
In-Reply-To: <pull.845.v2.git.1615248599.gitgitgadget@gmail.com>

From: Elijah Newren <newren@gmail.com>

In order to determine whether directory rename detection is needed, we as a pre-requisite need a way to traverse through all the files in a given tree before visiting any directories within that tree. traverse_trees() only iterates through the entries in the order they appear, so add some data structures that will store all the entries as we iterate through them in traverse_trees(), which will allow us to re-traverse them in our desired order.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
 merge-ort.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/merge-ort.c b/merge-ort.c
index 83aa4c08121f..d49cfa8b030b 100644
--- a/merge-ort.c
+++ b/merge-ort.c
@@ -51,6 +51,12 @@ enum merge_side {
 	MERGE_SIDE2 = 2
 };
 
+struct traversal_callback_data {
+	unsigned long mask;
+	unsigned long dirmask;
+	struct name_entry names[3];
+};
+
 struct rename_info {
 	/*
 	 * All variables that are arrays of size 3 correspond to data tracked
@@ -102,6 +108,22 @@ struct rename_info {
 	 */
 	struct strset relevant_sources[3];
 
+	/*
+	 * callback_data_*: supporting data structures for alternate traversal
+	 *
+	 * We sometimes need to be able to traverse through all the files
+	 * in a given tree before all immediate subdirectories within that
+	 * tree.  Since traverse_trees() doesn't do that naturally, we have
+	 * a traverse_trees_wrapper() that stores any immediate
+	 * subdirectories while traversing files, then traverses the
+	 * immediate subdirectories later.  These callback_data* variables
+	 * store the information for the subdirectories so that we can do
+	 * that traversal order.
+	 */
+	struct traversal_callback_data *callback_data;
+	int callback_data_nr, callback_data_alloc;
+	char *callback_data_traverse_path;
+
 	/*
 	 * needed_limit: value needed for inexact rename detection to run
 	 *
@@ -396,6 +418,10 @@ static void clear_or_reinit_internal_opts(struct merge_options_internal *opti,
 		}
 		strmap_clear(&opti->output, 0);
 	}
+
+	/* Clean out callback_data as well. */
+	FREE_AND_NULL(renames->callback_data);
+	renames->callback_data_nr = renames->callback_data_alloc = 0;
 }
 
 static int err(struct merge_options *opt, const char *err, ...)

-- 
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