Merge branch 'jk/relative-directory-fix'

Some codepaths, including the refs API, get and keep relative
paths, that go out of sync when the process does chdir(2).  The
chdir-notify API is introduced to let these codepaths adjust these
cached paths to the new current directory.

* jk/relative-directory-fix:
  refs: use chdir_notify to update cached relative paths
  set_work_tree: use chdir_notify
  add chdir-notify API
  trace.c: export trace_setup_key
  set_git_dir: die when setenv() fails

1 files changed, 23 insertions, 3 deletions

diff --git a/environment.c b/environment.c
index 39b3d90..fd970b8 100644
--- a/environment.c
+++ b/environment.c
@@ -15,6 +15,7 @@
 #include "commit.h"
 #include "argv-array.h"
 #include "object-store.h"
+#include "chdir-notify.h"
 
 int trust_executable_bit = 1;
 int trust_ctime = 1;
@@ -323,12 +324,31 @@ char *get_graft_file(void)
 	return the_repository->graft_file;
 }
 
-int set_git_dir(const char *path)
+static void set_git_dir_1(const char *path)
 {
 	if (setenv(GIT_DIR_ENVIRONMENT, path, 1))
-		return error("Could not set GIT_DIR to '%s'", path);
+		die("could not set GIT_DIR to '%s'", path);
 	setup_git_env(path);
-	return 0;
+}
+
+static void update_relative_gitdir(const char *name,
+				   const char *old_cwd,
+				   const char *new_cwd,
+				   void *data)
+{
+	char *path = reparent_relative_path(old_cwd, new_cwd, get_git_dir());
+	trace_printf_key(&trace_setup_key,
+			 "setup: move $GIT_DIR to '%s'",
+			 path);
+	set_git_dir_1(path);
+	free(path);
+}
+
+void set_git_dir(const char *path)
+{
+	set_git_dir_1(path);
+	if (!is_absolute_path(path))
+		chdir_notify_register(NULL, update_relative_gitdir, NULL);
 }
 
 const char *get_log_output_encoding(void)