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[PATCH v2 17/19] Allow to undo setup_git_directory_gently() gracefully (and fix alias code)

From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date
Mar 21, 2010, 10:30 UTC
Message-ID
<1269167446-7799-18-git-send-email-pclouds@gmail.com>
In-Reply-To
<1269167446-7799-1-git-send-email-pclouds@gmail.com>

unset_git_directory() can only clean up things as long as set_git_dir() has not been called because set_git_dir() sets internal state itself. Even worse, set_git_dir() may override $GIT_DIR env variable.

Add unset_git_env() to undo set_git_dir(), allow unset_git_directory() to undo a succesful setup_git_directory_gently().

While at there, fix alias handling code regarding git_dir {,un-}setup, use unset_git_directory() instead of just chdir() back.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 cache.h       |    1 +
 environment.c |   20 ++++++++++++++++++++
 git.c         |   11 +++++------
 setup.c       |    2 ++
 4 files changed, 28 insertions(+), 6 deletions(-)
diff --git a/cache.h b/cache.h
index e397e1d..b1ed150 100644
--- a/cache.h
+++ b/cache.h
@@ -419,6 +419,7 @@ extern void setup_work_tree(void);
 extern const char *setup_git_directory_gently(int *);
 extern const char *setup_git_directory(void);
 extern void unset_git_directory(const char *prefix);
+extern void unset_git_env();
 extern const char *prefix_path(const char *prefix, int len, const char *path);
 extern const char *prefix_filename(const char *prefix, int len, const char *path);
 extern int check_filename(const char *prefix, const char *name);
diff --git a/environment.c b/environment.c
index c36c902..6127025 100644
--- a/environment.c
+++ b/environment.c
@@ -62,6 +62,7 @@ char *git_work_tree_cfg;
 static char *work_tree;
 
 static const char *git_dir;
+static const char *original_git_dir;
 static char *git_object_dir, *git_index_file, *git_refs_dir, *git_graft_file;
 
 /*
@@ -81,6 +82,20 @@ const char * const local_repo_env[LOCAL_REPO_ENV_SIZE + 1] = {
 	NULL
 };
 
+void unset_git_env(void)
+{
+	git_dir = NULL;
+	if (original_git_dir)
+		setenv(GIT_DIR_ENVIRONMENT, original_git_dir, 1);
+	else
+		unsetenv(GIT_DIR_ENVIRONMENT);
+	git_object_dir = NULL;
+	git_refs_dir = NULL;
+	git_index_file = NULL;
+	git_graft_file = NULL;
+	read_replace_refs = 1;
+}
+
 static void setup_git_env(void)
 {
 	git_dir = getenv(GIT_DIR_ENVIRONMENT);
@@ -184,6 +199,11 @@ char *get_graft_file(void)
 
 int set_git_dir(const char *path)
 {
+	static int original_git_dir_set = 0;
+	if (!original_git_dir_set) {
+		original_git_dir = getenv(GIT_DIR_ENVIRONMENT);
+		original_git_dir_set = 1;
+	}
 	if (setenv(GIT_DIR_ENVIRONMENT, path, 1))
 		return error("Could not set GIT_DIR to '%s'", path);
 	setup_git_env();
diff --git a/git.c b/git.c
index 7e30498..db5bd95 100644
--- a/git.c
+++ b/git.c
@@ -146,14 +146,13 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
 static int handle_alias(int *argcp, const char ***argv)
 {
 	int envchanged = 0, ret = 0, saved_errno = errno;
-	const char *subdir;
 	int count, option_count;
 	const char **new_argv;
 	const char *alias_command;
 	char *alias_string;
 	int unused_nongit;
 
-	subdir = setup_git_directory_gently(&unused_nongit);
+	setup_git_directory_gently(&unused_nongit);
 
 	alias_command = (*argv)[0];
 	alias_string = alias_lookup(alias_command);
@@ -210,8 +209,7 @@ static int handle_alias(int *argcp, const char ***argv)
 		ret = 1;
 	}
 
-	if (subdir && chdir(subdir))
-		die_errno("Cannot change to '%s'", subdir);
+	unset_git_directory(startup_info->prefix);
 
 	errno = saved_errno;
 
@@ -240,8 +238,6 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 	int status;
 	struct stat st;
 
-	memset(&git_startup_info, 0, sizeof(git_startup_info));
-	startup_info = &git_startup_info;
 	startup_info->help = argc == 2 && !strcmp(argv[1], "-h");
 	if (!startup_info->help) {
 		if (p->option & RUN_SETUP)
@@ -486,6 +482,9 @@ int main(int argc, const char **argv)
 {
 	const char *cmd;
 
+	memset(&git_startup_info, 0, sizeof(git_startup_info));
+	startup_info = &git_startup_info;
+
 	cmd = git_extract_argv0_path(argv[0]);
 	if (!cmd)
 		cmd = "git-help";
diff --git a/setup.c b/setup.c
index 4de7bf0..1808ebe 100644
--- a/setup.c
+++ b/setup.c
@@ -336,6 +336,8 @@ void unset_git_directory(const char *prefix)
 		die("Cannot change to '%s'", prefix);
 
 	if (startup_info) {
+		if (startup_info->have_repository)
+			unset_git_env();
 		startup_info->prefix = NULL;
 		startup_info->have_repository = 0;
 	}

-- 
1.7.0.2.425.gb99f1
Previous: Nguyễn Thái Ngọc DuyNext: Nguyễn Thái Ngọc Duy
Message 18 of 20 in “nd/setup part two, second round”
  1. 00/19 nd/setup part two, second roundNguyễn Thái Ngọc Duy, Mar 21, 2010
  2. 01/19 Move enter_repo() to setup.cNguyễn Thái Ngọc Duy, Mar 21, 2010
  3. 02/19 enter_repo(): initialize other variables as setup_git_directory_gently() doesNguyễn Thái Ngọc Duy, Mar 21, 2010
  4. 03/19 rev-parse --git-dir: print relative gitdir correctlyNguyễn Thái Ngọc Duy, Mar 21, 2010
  5. 04/19 worktree setup: call set_git_dir explicitlyNguyễn Thái Ngọc Duy, Mar 21, 2010
  6. 05/19 Add git_config_early()Nguyễn Thái Ngọc Duy, Mar 21, 2010
  7. 06/19 Use git_config_early() instead of git_config() during repo setupNguyễn Thái Ngọc Duy, Mar 21, 2010
  8. 07/19 worktree setup: restore original state when things go wrongNguyễn Thái Ngọc Duy, Mar 21, 2010
  9. 08/19 init/clone: turn on startup->have_repository properlyNguyễn Thái Ngọc Duy, Mar 21, 2010
  10. 09/19 git_config(): do not read .git/config if there is no repositoryNguyễn Thái Ngọc Duy, Mar 21, 2010
  11. 10/19 Do not read .git/info/exclude if there is no repositoryNguyễn Thái Ngọc Duy, Mar 21, 2010
  12. 11/19 Do not read .git/info/attributes if there is no repositoryNguyễn Thái Ngọc Duy, Mar 21, 2010
  13. 12/19 apply: do not check sha1 when repository has not been foundNguyễn Thái Ngọc Duy, Mar 21, 2010
  14. 13/19 config: do not read .git/config if there is no repositoryNguyễn Thái Ngọc Duy, Mar 21, 2010
  15. 14/19 run_builtin(): save "-h" detection result for later useNguyễn Thái Ngọc Duy, Mar 21, 2010
  16. 15/19 builtins: utilize startup_info->help where possibleNguyễn Thái Ngọc Duy, Mar 21, 2010
  17. 16/19 builtins: check for startup_info->help, print and exit earlyNguyễn Thái Ngọc Duy, Mar 21, 2010
  18. 17/19 Allow to undo setup_git_directory_gently() gracefully (and fix alias code)Nguyễn Thái Ngọc Duy, Mar 21, 2010
  19. 18/19 alias: keep repository found while collecting aliases as long as possibleNguyễn Thái Ngọc Duy, Mar 21, 2010
  20. 19/19 Guard unallowed access to repository when it's not set upNguyễn Thái Ngọc Duy, Mar 21, 2010

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