environment: move `set_git_dir()` and related into setup layer

The functions `set_git_dir()` and friends are used to set up
repositories. As such, they are quite clearly part of the setup
subsystem, but still live in "environment.c". Move them over, which also
helps to get rid of dependencies on `the_repository` in the environment
subsystem.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 106 insertions, 0 deletions

diff --git a/setup.c b/setup.c
index 1bfec288ab..19cce5afa7 100644
--- a/setup.c
+++ b/setup.c
@@ -7,16 +7,22 @@
 #include "exec-cmd.h"
 #include "gettext.h"
 #include "hex.h"
+#include "object-file.h"
 #include "object-name.h"
 #include "refs.h"
+#include "replace-object.h"
 #include "repository.h"
 #include "config.h"
 #include "dir.h"
 #include "setup.h"
+#include "shallow.h"
 #include "string-list.h"
+#include "strvec.h"
 #include "chdir-notify.h"
 #include "path.h"
 #include "quote.h"
+#include "tmp-objdir.h"
+#include "trace.h"
 #include "trace2.h"
 #include "worktree.h"
 #include "exec-cmd.h"
@@ -1613,6 +1619,106 @@ enum discovery_result discover_git_directory_reason(struct strbuf *commondir,
 	return result;
 }
 
+void setup_git_env(const char *git_dir)
+{
+	char *git_replace_ref_base;
+	const char *shallow_file;
+	const char *replace_ref_base;
+	struct set_gitdir_args args = { NULL };
+	struct strvec to_free = STRVEC_INIT;
+
+	args.commondir = getenv_safe(&to_free, GIT_COMMON_DIR_ENVIRONMENT);
+	args.object_dir = getenv_safe(&to_free, DB_ENVIRONMENT);
+	args.graft_file = getenv_safe(&to_free, GRAFT_ENVIRONMENT);
+	args.index_file = getenv_safe(&to_free, INDEX_ENVIRONMENT);
+	args.alternate_db = getenv_safe(&to_free, ALTERNATE_DB_ENVIRONMENT);
+	if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
+		args.disable_ref_updates = 1;
+	}
+
+	repo_set_gitdir(the_repository, git_dir, &args);
+	strvec_clear(&to_free);
+
+	if (getenv(NO_REPLACE_OBJECTS_ENVIRONMENT))
+		disable_replace_refs();
+	replace_ref_base = getenv(GIT_REPLACE_REF_BASE_ENVIRONMENT);
+	git_replace_ref_base = xstrdup(replace_ref_base ? replace_ref_base
+							  : "refs/replace/");
+	update_ref_namespace(NAMESPACE_REPLACE, git_replace_ref_base);
+
+	shallow_file = getenv(GIT_SHALLOW_FILE_ENVIRONMENT);
+	if (shallow_file)
+		set_alternate_shallow_file(the_repository, shallow_file, 0);
+
+	if (git_env_bool(NO_LAZY_FETCH_ENVIRONMENT, 0))
+		fetch_if_missing = 0;
+}
+
+static void set_git_dir_1(const char *path)
+{
+	xsetenv(GIT_DIR_ENVIRONMENT, path, 1);
+	setup_git_env(path);
+}
+
+static void update_relative_gitdir(const char *name UNUSED,
+				   const char *old_cwd,
+				   const char *new_cwd,
+				   void *data UNUSED)
+{
+	char *path = reparent_relative_path(old_cwd, new_cwd,
+					    repo_get_git_dir(the_repository));
+	struct tmp_objdir *tmp_objdir = tmp_objdir_unapply_primary_odb();
+
+	trace_printf_key(&trace_setup_key,
+			 "setup: move $GIT_DIR to '%s'",
+			 path);
+	set_git_dir_1(path);
+	if (tmp_objdir)
+		tmp_objdir_reapply_primary_odb(tmp_objdir, old_cwd, new_cwd);
+	free(path);
+}
+
+void set_git_dir(const char *path, int make_realpath)
+{
+	struct strbuf realpath = STRBUF_INIT;
+
+	if (make_realpath) {
+		strbuf_realpath(&realpath, path, 1);
+		path = realpath.buf;
+	}
+
+	set_git_dir_1(path);
+	if (!is_absolute_path(path))
+		chdir_notify_register(NULL, update_relative_gitdir, NULL);
+
+	strbuf_release(&realpath);
+}
+
+static int git_work_tree_initialized;
+
+/*
+ * Note.  This works only before you used a work tree.  This was added
+ * primarily to support git-clone to work in a new repository it just
+ * created, and is not meant to flip between different work trees.
+ */
+void set_git_work_tree(const char *new_work_tree)
+{
+	if (git_work_tree_initialized) {
+		struct strbuf realpath = STRBUF_INIT;
+
+		strbuf_realpath(&realpath, new_work_tree, 1);
+		new_work_tree = realpath.buf;
+		if (strcmp(new_work_tree, the_repository->worktree))
+			die("internal error: work tree has already been set\n"
+			    "Current worktree: %s\nNew worktree: %s",
+			    the_repository->worktree, new_work_tree);
+		strbuf_release(&realpath);
+		return;
+	}
+	git_work_tree_initialized = 1;
+	repo_set_worktree(the_repository, new_work_tree);
+}
+
 const char *setup_git_directory_gently(int *nongit_ok)
 {
 	static struct strbuf cwd = STRBUF_INIT;