real_pathdup(): fix callsites that wanted it to die on error

In 4ac9006f832 (real_path: have callers use real_pathdup and
strbuf_realpath, 2016-12-12), we changed the xstrdup(real_path())
pattern to use real_pathdup() directly.

The problem with this change is that real_path() calls
strbuf_realpath() with die_on_error = 1 while real_pathdup() calls
it with die_on_error = 0. Meaning that in cases where real_path()
causes Git to die() with an error message, real_pathdup() is silent
and returns NULL instead.

The callers, however, are ill-prepared for that change, as they expect
the return value to be non-NULL (and otherwise the function died
with an appropriate error message).

Fix this by extending real_pathdup()'s signature to accept the
die_on_error flag and simply pass it through to strbuf_realpath(),
and then adjust all callers after a careful audit whether they would
handle NULLs well.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/setup.c b/setup.c
index 967f289f1e..6b48cb91ff 100644
--- a/setup.c
+++ b/setup.c
@@ -698,7 +698,7 @@ static const char *setup_discovered_git_dir(const char *gitdir,
 	/* --work-tree is set without --git-dir; use discovered one */
 	if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
 		if (offset != cwd->len && !is_absolute_path(gitdir))
-			gitdir = real_pathdup(gitdir);
+			gitdir = real_pathdup(gitdir, 1);
 		if (chdir(cwd->buf))
 			die_errno("Could not come back to cwd");
 		return setup_explicit_git_dir(gitdir, cwd, nongit_ok);
@@ -806,7 +806,7 @@ static int canonicalize_ceiling_entry(struct string_list_item *item,
 		/* Keep entry but do not canonicalize it */
 		return 1;
 	} else {
-		char *real_path = real_pathdup(ceil);
+		char *real_path = real_pathdup(ceil, 0);
 		if (!real_path) {
 			return 0;
 		}