sparse-index: refactor path_found()

In advance of changing the behavior of path_found(), take all of the
intermediate data values and group them into a single struct. This
simplifies the method prototype as well as the initialization. Future
changes can be made directly to the struct and method without changing
the callers with this approach.

Note that the clear_path_found_data() method is currently empty, as
there is nothing to free. This method is a placeholder for future
changes that require a non-trivial implementation. Its stub is created
now so consumers could call it now and not change in future changes.

Signed-off-by: Derrick Stolee <[email protected]>
Reviewed-by: Elijah Newren <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: derrickstolee

sparse-index.c

@@ -439,8 +439,22 @@ void ensure_correct_sparsity(struct index_state *istate)
 		ensure_full_index(istate);
 }
 
-static int path_found(const char *path, const char **dirname, size_t *dir_len,
-		      int *dir_found)
+struct path_found_data {
+	const char *dirname;
+	size_t dir_len;
+	int dir_found;
+};
+
+#define PATH_FOUND_DATA_INIT { \
+	.dir_found = 1 \
+}
+
+static void clear_path_found_data(struct path_found_data *data)
+{
+	return;
+}
+
+static int path_found(const char *path, struct path_found_data *data)
 {
 	struct stat st;
 	char *newdir;
@@ -450,7 +464,7 @@ static int path_found(const char *path, const char **dirname, size_t *dir_len,
 	 * If dirname corresponds to a directory that doesn't exist, and this
 	 * path starts with dirname, then path can't exist.
 	 */
-	if (!*dir_found && !memcmp(path, *dirname, *dir_len))
+	if (!data->dir_found && !memcmp(path, data->dirname, data->dir_len))
 		return 0;
 
 	/*
@@ -472,25 +486,24 @@ static int path_found(const char *path, const char **dirname, size_t *dir_len,
 	 * If path starts with directory (which we already lstat'ed and found),
 	 * then no need to lstat parent directory again.
 	 */
-	if (*dir_found && *dirname && memcmp(path, *dirname, *dir_len))
+	if (data->dir_found && data->dirname &&
+	    memcmp(path, data->dirname, data->dir_len))
 		return 0;
 
 	/* Free previous dirname, and cache path's dirname */
-	*dirname = path;
-	*dir_len = newdir - path + 1;
+	data->dirname = path;
+	data->dir_len = newdir - path + 1;
 
-	tmp = xstrndup(path, *dir_len);
-	*dir_found = !lstat(tmp, &st);
+	tmp = xstrndup(path, data->dir_len);
+	data->dir_found = !lstat(tmp, &st);
 	free(tmp);
 
 	return 0;
 }
 
 static int clear_skip_worktree_from_present_files_sparse(struct index_state *istate)
 {
-	const char *last_dirname = NULL;
-	size_t dir_len = 0;
-	int dir_found = 1;
+	struct path_found_data data = PATH_FOUND_DATA_INIT;
 
 	int path_count = 0;
 	int to_restart = 0;
@@ -502,7 +515,7 @@ static int clear_skip_worktree_from_present_files_sparse(struct index_state *ist
 
 		if (ce_skip_worktree(ce)) {
 			path_count++;
-			if (path_found(ce->name, &last_dirname, &dir_len, &dir_found)) {
+			if (path_found(ce->name, &data)) {
 				if (S_ISSPARSEDIR(ce->ce_mode)) {
 					to_restart = 1;
 					break;
@@ -516,14 +529,13 @@ static int clear_skip_worktree_from_present_files_sparse(struct index_state *ist
 			   "sparse_path_count", path_count);
 	trace2_region_leave("index", "clear_skip_worktree_from_present_files_sparse",
 			    istate->repo);
+	clear_path_found_data(&data);
 	return to_restart;
 }
 
 static void clear_skip_worktree_from_present_files_full(struct index_state *istate)
 {
-	const char *last_dirname = NULL;
-	size_t dir_len = 0;
-	int dir_found = 1;
+	struct path_found_data data = PATH_FOUND_DATA_INIT;
 
 	int path_count = 0;
 
@@ -537,7 +549,7 @@ static void clear_skip_worktree_from_present_files_full(struct index_state *ista
 
 		if (ce_skip_worktree(ce)) {
 			path_count++;
-			if (path_found(ce->name, &last_dirname, &dir_len, &dir_found))
+			if (path_found(ce->name, &data))
 				ce->ce_flags &= ~CE_SKIP_WORKTREE;
 		}
 	}
@@ -546,6 +558,7 @@ static void clear_skip_worktree_from_present_files_full(struct index_state *ista
 			   "full_path_count", path_count);
 	trace2_region_leave("index", "clear_skip_worktree_from_present_files_full",
 			    istate->repo);
+	clear_path_found_data(&data);
 }
 
 void clear_skip_worktree_from_present_files(struct index_state *istate)