[PATCH v2 5/5] refs: use chdir_notify to update cached relative paths

From

Jeff King <peff@peff.net>

Date

Mar 30, 2018, 18:35 UTC

Message-ID

<20180330183512.GE31135@sigill.intra.peff.net>

In-Reply-To

<20180330183425.GA30575@sigill.intra.peff.net>

  - when we initialize the ref backend, we make a copy of
    get_git_dir(), which may be relative

  - later, we may call setup_work_tree() and chdir to the
    root of the working tree

  - further calls to the ref code will use the stored git
    directory, but relative paths will now point to the
    wrong place

Reported-by: Rafael Ascensao <rafa.almas@gmail.com>
Helped-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
---
 refs/files-backend.c  |  6 ++++++
 refs/packed-backend.c |  3 +++
 t/t1501-work-tree.sh  | 12 ++++++++++++
 3 files changed, 21 insertions(+)

diff --git a/refs/files-backend.c b/refs/files-backend.c
index bec8e30e9e..a92a2aa821 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -9,6 +9,7 @@
 #include "../lockfile.h"
 #include "../object.h"
 #include "../dir.h"
+#include "../chdir-notify.h"
 
 /*
  * This backend uses the following flags in `ref_update::flags` for
@@ -106,6 +107,11 @@ static struct ref_store *files_ref_store_create(const char *gitdir,
 	refs->packed_ref_store = packed_ref_store_create(sb.buf, flags);
 	strbuf_release(&sb);
 
+	chdir_notify_reparent("files-backend $GIT_DIR",
+			      &refs->gitdir);
+	chdir_notify_reparent("files-backend $GIT_COMMONDIR",
+			      &refs->gitcommondir);
+
 	return ref_store;
 }
 
diff --git a/refs/packed-backend.c b/refs/packed-backend.c
index 65288c6472..369c34f886 100644
--- a/refs/packed-backend.c
+++ b/refs/packed-backend.c
@@ -5,6 +5,7 @@
 #include "packed-backend.h"
 #include "../iterator.h"
 #include "../lockfile.h"
+#include "../chdir-notify.h"
 
 enum mmap_strategy {
 	/*
@@ -202,6 +203,8 @@ struct ref_store *packed_ref_store_create(const char *path,
 	refs->store_flags = store_flags;
 
 	refs->path = xstrdup(path);
+	chdir_notify_reparent("packed-refs", &refs->path);
+
 	return ref_store;
 }
 
diff --git a/t/t1501-work-tree.sh b/t/t1501-work-tree.sh
index b06210ec5e..a5db53337b 100755
--- a/t/t1501-work-tree.sh
+++ b/t/t1501-work-tree.sh
@@ -431,4 +431,16 @@ test_expect_success 'error out gracefully on invalid $GIT_WORK_TREE' '
 	)
 '
 
+test_expect_success 'refs work with relative gitdir and work tree' '
+	git init relative &&
+	git -C relative commit --allow-empty -m one &&
+	git -C relative commit --allow-empty -m two &&
+
+	GIT_DIR=relative/.git GIT_WORK_TREE=relative git reset HEAD^ &&
+
+	git -C relative log -1 --format=%s >actual &&
+	echo one >expect &&
+	test_cmp expect actual
+'
+
 test_done

-- 
2.17.0.rc2.594.gdb94a0ce02