[PATCH v2 1/5] worktree repair: align .git file handling with repair_gitfile()

["Yoichi NAKAYAMA via GitGitGadget" <gitgitgadget@gmail.com>]

From: Yoichi NAKAYAMA <yoichi.nakayama@gmail.com>

Use read_gitfile_raw() instead of read_gitfile_gently() in
repair_worktree_at_path(), moving path resolution and repository
validation to the caller. This makes .git file handling consistent
with repair_gitfile() and avoids using the non-reentrant
read_gitfile_gently().

A subsequent commit will update infer_backlink() to use
read_gitfile_raw() as well.

Signed-off-by: Yoichi NAKAYAMA <yoichi.nakayama@gmail.com>
---
 worktree.c | 40 ++++++++++++++++++++++++++++------------
 1 file changed, 28 insertions(+), 12 deletions(-)

diff --git a/worktree.c b/worktree.c
index 8cb8637b18..4492ca835d 100644
--- a/worktree.c
+++ b/worktree.c
@@ -840,7 +840,7 @@ void repair_worktree_at_path(struct repository *repo,
 	struct strbuf inferred_backlink = STRBUF_INIT;
 	struct strbuf gitdir = STRBUF_INIT;
 	struct strbuf olddotgit = STRBUF_INIT;
-	char *dotgit_contents = NULL;
+	struct strbuf contents = STRBUF_INIT;
 	const char *repair = NULL;
 	int err;
 
@@ -858,14 +858,26 @@ void repair_worktree_at_path(struct repository *repo,
 
 	infer_backlink(repo, dotgit.buf, &inferred_backlink);
 	strbuf_realpath_forgiving(&inferred_backlink, inferred_backlink.buf, 0);
-	dotgit_contents = xstrdup_or_null(read_gitfile_gently(dotgit.buf, &err));
-	if (dotgit_contents) {
-		strbuf_addstr(&backlink, dotgit_contents);
-	} else if (err == READ_GITFILE_ERR_NOT_A_FILE ||
-			err == READ_GITFILE_ERR_IS_A_DIR) {
-		fn(1, dotgit.buf, _("unable to locate repository; .git is not a file"), cb_data);
+	err = read_gitfile_raw(&contents, dotgit.buf);
+	if (!err) {
+		const char *dotgit_contents = contents.buf;
+		if (is_absolute_path(dotgit_contents)) {
+			strbuf_addstr(&backlink, dotgit_contents);
+		} else {
+			strbuf_addbuf(&backlink, &dotgit);
+			strbuf_strip_suffix(&backlink, ".git");
+			strbuf_addstr(&backlink, dotgit_contents);
+			strbuf_realpath_forgiving(&backlink, backlink.buf, 0);
+		}
+	}
+	if (err == READ_GITFILE_ERR_NOT_A_FILE ||
+	    err == READ_GITFILE_ERR_IS_A_DIR) {
+		fn(1, dotgit.buf,
+		   _("unable to locate repository; .git is not a file"),
+		   cb_data);
 		goto done;
-	} else if (err == READ_GITFILE_ERR_NOT_A_REPO) {
+	} else if (!err && !is_git_directory(backlink.buf)) {
+		strbuf_release(&backlink);
 		if (inferred_backlink.len) {
 			/*
 			 * Worktree's .git file does not point at a repository
@@ -876,11 +888,15 @@ void repair_worktree_at_path(struct repository *repo,
 			 */
 			strbuf_swap(&backlink, &inferred_backlink);
 		} else {
-			fn(1, dotgit.buf, _("unable to locate repository; .git file does not reference a repository"), cb_data);
+			fn(1, dotgit.buf,
+			   _("unable to locate repository; .git file does not reference a repository"),
+			   cb_data);
 			goto done;
 		}
-	} else {
-		fn(1, dotgit.buf, _("unable to locate repository; .git file broken"), cb_data);
+	} else if (err) {
+		fn(1, dotgit.buf,
+		   _("unable to locate repository; .git file broken"),
+		   cb_data);
 		goto done;
 	}
 
@@ -926,12 +942,12 @@ void repair_worktree_at_path(struct repository *repo,
 					     gitdir.buf, use_relative_paths);
 	}
 done:
-	free(dotgit_contents);
 	strbuf_release(&olddotgit);
 	strbuf_release(&backlink);
 	strbuf_release(&inferred_backlink);
 	strbuf_release(&gitdir);
 	strbuf_release(&dotgit);
+	strbuf_release(&contents);
 }
 
 int should_prune_worktree(struct repository *repo,
-- 
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