git@vger.kernel.org list mirror (unofficial, one of many)
 help / color / mirror / code / Atom feed
From: "Glen Choo via GitGitGadget" <gitgitgadget@gmail.com>
To: git@vger.kernel.org
Cc: Taylor Blau <me@ttaylorr.com>,
	"brian m. carlson" <sandals@crustytoothpaste.net>,
	Derrick Stolee <derrickstolee@github.com>,
	Junio C Hamano <gitster@pobox.com>,
	Emily Shaffer <emilyshaffer@google.com>,
	Glen Choo <chooglen@google.com>, Glen Choo <chooglen@google.com>
Subject: [PATCH v3 2/5] config: read protected config with `git_protected_config()`
Date: Fri, 27 May 2022 21:09:18 +0000	[thread overview]
Message-ID: <7499a2809615d42eaf3649e1c33f38d099d27c1a.1653685761.git.gitgitgadget@gmail.com> (raw)
In-Reply-To: <pull.1261.v3.git.git.1653685761.gitgitgadget@gmail.com>

From: Glen Choo <chooglen@google.com>

Protected config is read using `read_very_early_config()`, which has
several downsides:

- Every call to `read_very_early_config()` parses global and
  system-level config files anew, but this can be optimized by just
  parsing them once [1].
- Protected variables should respect "-c" because we can reasonably
  assume that it comes from the user. But, `read_very_early_config()`
  can't use "-c" because it is called so early that it does not have
  access to command line arguments.

Introduce `git_protected_config()`, which reads protected config and
caches the values in `the_repository.protected_config`. Then, refactor
`safe.directory` to use `git_protected_config()`.

This implementation can still be improved, however:

- `git_protected_config()` iterates through every variable in
  `the_repository.protected_config`, which may still be too expensive to
  be called in every "git" invocation. There exist constant time lookup
  functions for non-protected config (repo_config_get_*()), but for
  simplicity, this commit does not implement similar functions for
  protected config.

- Protected config is stored in `the_repository` so that we don't need
  to statically allocate it. But this might be confusing since protected
  config ignores repository config by definition.

[1] While `git_protected_config()` should save on file I/O, I wasn't
able to measure a meaningful difference between that and
`read_very_early_config()` on my machine (which has an SSD).

Signed-off-by: Glen Choo <chooglen@google.com>
---
 config.c     | 35 +++++++++++++++++++++++++++++++++++
 config.h     |  8 ++++++++
 repository.c |  5 +++++
 repository.h |  8 ++++++++
 setup.c      |  2 +-
 5 files changed, 57 insertions(+), 1 deletion(-)

diff --git a/config.c b/config.c
index fa471dbdb89..c30bb7c5d09 100644
--- a/config.c
+++ b/config.c
@@ -2614,6 +2614,41 @@ int repo_config_get_pathname(struct repository *repo,
 	return ret;
 }
 
+/* Read protected config into the_repository->protected_config. */
+static void read_protected_config(void)
+{
+	char *xdg_config = NULL, *user_config = NULL, *system_config = NULL;
+
+	CALLOC_ARRAY(the_repository->protected_config, 1);
+	git_configset_init(the_repository->protected_config);
+
+	system_config = git_system_config();
+	git_global_config(&user_config, &xdg_config);
+
+	git_configset_add_file(the_repository->protected_config, system_config);
+	git_configset_add_file(the_repository->protected_config, xdg_config);
+	git_configset_add_file(the_repository->protected_config, user_config);
+
+	free(system_config);
+	free(xdg_config);
+	free(user_config);
+}
+
+/* Ensure that the_repository->protected_config has been initialized. */
+static void git_protected_config_check_init(void)
+{
+	if (the_repository->protected_config &&
+	    the_repository->protected_config->hash_initialized)
+		return;
+	read_protected_config();
+}
+
+void git_protected_config(config_fn_t fn, void *data)
+{
+	git_protected_config_check_init();
+	configset_iter(the_repository->protected_config, fn, data);
+}
+
 /* Functions used historically to read configuration from 'the_repository' */
 void git_config(config_fn_t fn, void *data)
 {
diff --git a/config.h b/config.h
index 7654f61c634..411965f52b5 100644
--- a/config.h
+++ b/config.h
@@ -505,6 +505,14 @@ int repo_config_get_maybe_bool(struct repository *repo,
 int repo_config_get_pathname(struct repository *repo,
 			     const char *key, const char **dest);
 
+/*
+ * Functions for reading protected config. By definition, protected
+ * config ignores repository config, so it is unnecessary to read
+ * protected config from any `struct repository` other than
+ * the_repository.
+ */
+void git_protected_config(config_fn_t fn, void *data);
+
 /**
  * Querying For Specific Variables
  * -------------------------------
diff --git a/repository.c b/repository.c
index 5d166b692c8..ec319a5e09a 100644
--- a/repository.c
+++ b/repository.c
@@ -295,6 +295,11 @@ void repo_clear(struct repository *repo)
 		FREE_AND_NULL(repo->remote_state);
 	}
 
+	if (repo->protected_config) {
+		git_configset_clear(repo->protected_config);
+		FREE_AND_NULL(repo->protected_config);
+	}
+
 	repo_clear_path_cache(&repo->cached_paths);
 }
 
diff --git a/repository.h b/repository.h
index 6cc661e5a43..24251aac553 100644
--- a/repository.h
+++ b/repository.h
@@ -126,6 +126,14 @@ struct repository {
 
 	struct repo_settings settings;
 
+	/*
+	 * Config that comes from trusted sources, namely
+	 * - system config files (e.g. /etc/gitconfig)
+	 * - global config files (e.g. $HOME/.gitconfig,
+	 *   $XDG_CONFIG_HOME/git)
+	 */
+	struct config_set *protected_config;
+
 	/* Subsystems */
 	/*
 	 * Repository's config which contains key-value pairs from the usual
diff --git a/setup.c b/setup.c
index f818dd858c6..847d47f9195 100644
--- a/setup.c
+++ b/setup.c
@@ -1128,7 +1128,7 @@ static int ensure_valid_ownership(const char *path)
 	    is_path_owned_by_current_user(path))
 		return 1;
 
-	read_very_early_config(safe_directory_cb, &data);
+	git_protected_config(safe_directory_cb, &data);
 
 	return data.is_safe;
 }
-- 
gitgitgadget


  parent reply	other threads:[~2022-05-27 21:10 UTC|newest]

Thread overview: 113+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-06 18:30 [PATCH] [RFC] setup.c: make bare repo discovery optional Glen Choo via GitGitGadget
2022-05-06 20:33 ` Junio C Hamano
2022-05-09 21:42 ` Taylor Blau
2022-05-09 22:54   ` Junio C Hamano
2022-05-09 23:57     ` Taylor Blau
2022-05-10  0:23       ` Junio C Hamano
2022-05-10 22:00   ` Glen Choo
2022-05-13 23:37 ` [PATCH v2 0/2] " Glen Choo via GitGitGadget
2022-05-13 23:37   ` [PATCH v2 1/2] " Glen Choo via GitGitGadget
2022-05-16 18:12     ` Glen Choo
2022-05-16 18:46     ` Derrick Stolee
2022-05-16 22:25       ` Taylor Blau
2022-05-17 20:24       ` Glen Choo
2022-05-17 21:51         ` Glen Choo
2022-05-13 23:37   ` [PATCH v2 2/2] setup.c: learn discovery.bareRepository=cwd Glen Choo via GitGitGadget
2022-05-16 18:49     ` Derrick Stolee
2022-05-16 16:40   ` [PATCH v2 0/2] setup.c: make bare repo discovery optional Junio C Hamano
2022-05-16 18:36     ` Glen Choo
2022-05-16 19:16       ` Junio C Hamano
2022-05-16 20:27         ` Glen Choo
2022-05-16 22:16           ` Junio C Hamano
2022-05-16 16:43   ` Junio C Hamano
2022-05-16 19:07   ` Derrick Stolee
2022-05-16 22:43     ` Taylor Blau
2022-05-16 23:19     ` Junio C Hamano
2022-05-17 18:56     ` Glen Choo
2022-05-27 21:09   ` [PATCH v3 0/5] config: introduce discovery.bare and protected config Glen Choo via GitGitGadget
2022-05-27 21:09     ` [PATCH v3 1/5] Documentation: define protected configuration Glen Choo via GitGitGadget
2022-05-27 23:29       ` Junio C Hamano
2022-06-02 12:42         ` Derrick Stolee
2022-06-02 16:53           ` Junio C Hamano
2022-06-02 17:39             ` Glen Choo
2022-06-03 15:57         ` Glen Choo
2022-05-27 21:09     ` Glen Choo via GitGitGadget [this message]
2022-05-28  0:28       ` [PATCH v3 2/5] config: read protected config with `git_protected_config()` Junio C Hamano
2022-05-31 17:43         ` Glen Choo
2022-06-01 15:58           ` Junio C Hamano
2022-06-02 12:56       ` Derrick Stolee
2022-05-27 21:09     ` [PATCH v3 3/5] setup.c: create `discovery.bare` Glen Choo via GitGitGadget
2022-05-28  0:59       ` Junio C Hamano
2022-06-02 13:11       ` Derrick Stolee
2022-05-27 21:09     ` [PATCH v3 4/5] config: include "-c" in protected config Glen Choo via GitGitGadget
2022-06-02 13:15       ` Derrick Stolee
2022-05-27 21:09     ` [PATCH v3 5/5] upload-pack: make uploadpack.packObjectsHook protected Glen Choo via GitGitGadget
2022-06-02 13:18       ` Derrick Stolee
2022-06-07 20:57     ` [PATCH v4 0/5] config: introduce discovery.bare and protected config Glen Choo via GitGitGadget
2022-06-07 20:57       ` [PATCH v4 1/5] Documentation/git-config.txt: add SCOPES section Glen Choo via GitGitGadget
2022-06-07 20:57       ` [PATCH v4 2/5] Documentation: define protected configuration Glen Choo via GitGitGadget
2022-06-22 21:58         ` Jonathan Tan
2022-06-23 18:21           ` Glen Choo
2022-06-07 20:57       ` [PATCH v4 3/5] config: read protected config with `git_protected_config()` Glen Choo via GitGitGadget
2022-06-07 22:49         ` Junio C Hamano
2022-06-08  0:22           ` Glen Choo
2022-06-07 20:57       ` [PATCH v4 4/5] safe.directory: use git_protected_config() Glen Choo via GitGitGadget
2022-06-07 20:57       ` [PATCH v4 5/5] setup.c: create `discovery.bare` Glen Choo via GitGitGadget
2022-06-07 21:37         ` Glen Choo
2022-06-22 22:03       ` [PATCH v4 0/5] config: introduce discovery.bare and protected config Jonathan Tan
2022-06-23 17:13         ` Glen Choo
2022-06-23 18:32           ` Junio C Hamano
2022-06-27 17:34             ` Glen Choo
2022-06-27 18:19       ` Glen Choo
2022-06-27 18:36       ` [PATCH v5 " Glen Choo via GitGitGadget
2022-06-27 18:36         ` [PATCH v5 1/5] Documentation/git-config.txt: add SCOPES section Glen Choo via GitGitGadget
2022-06-27 18:36         ` [PATCH v5 2/5] Documentation: define protected configuration Glen Choo via GitGitGadget
2022-06-27 18:36         ` [PATCH v5 3/5] config: learn `git_protected_config()` Glen Choo via GitGitGadget
2022-06-27 18:36         ` [PATCH v5 4/5] safe.directory: use git_protected_config() Glen Choo via GitGitGadget
2022-06-27 18:36         ` [PATCH v5 5/5] setup.c: create `discovery.bare` Glen Choo via GitGitGadget
2022-06-30 13:20           ` Ævar Arnfjörð Bjarmason
2022-06-30 17:28             ` Glen Choo
2022-06-30 18:13         ` [PATCH v6 0/5] config: introduce discovery.bare and protected config Glen Choo via GitGitGadget
2022-06-30 18:13           ` [PATCH v6 1/5] Documentation/git-config.txt: add SCOPES section Glen Choo via GitGitGadget
2022-06-30 22:32             ` Taylor Blau
2022-07-06 17:44               ` Glen Choo
2022-06-30 18:13           ` [PATCH v6 2/5] Documentation: define protected configuration Glen Choo via GitGitGadget
2022-06-30 23:49             ` Taylor Blau
2022-07-06 18:21               ` Glen Choo
2022-06-30 18:13           ` [PATCH v6 3/5] config: learn `git_protected_config()` Glen Choo via GitGitGadget
2022-07-01  1:22             ` Taylor Blau
2022-07-06 22:42               ` Glen Choo
2022-06-30 18:13           ` [PATCH v6 4/5] safe.directory: use git_protected_config() Glen Choo via GitGitGadget
2022-06-30 18:13           ` [PATCH v6 5/5] setup.c: create `discovery.bare` Glen Choo via GitGitGadget
2022-07-01  1:30             ` Taylor Blau
2022-07-07 19:55               ` Glen Choo
2022-06-30 22:13           ` [PATCH v6 0/5] config: introduce discovery.bare and protected config Taylor Blau
2022-06-30 23:07           ` Ævar Arnfjörð Bjarmason
2022-07-01 17:37             ` Glen Choo
2022-07-08 21:58               ` Ævar Arnfjörð Bjarmason
2022-07-12 20:47                 ` Glen Choo
2022-07-12 23:53                   ` Ævar Arnfjörð Bjarmason
2022-07-07 23:01           ` [PATCH v7 " Glen Choo via GitGitGadget
2022-07-07 23:01             ` [PATCH v7 1/5] Documentation/git-config.txt: add SCOPES section Glen Choo via GitGitGadget
2022-07-07 23:43               ` Junio C Hamano
2022-07-08 17:01                 ` Glen Choo
2022-07-08 19:01                   ` Junio C Hamano
2022-07-08 21:38                     ` Glen Choo
2022-07-07 23:01             ` [PATCH v7 2/5] Documentation: define protected configuration Glen Choo via GitGitGadget
2022-07-08  0:39               ` Junio C Hamano
2022-07-07 23:01             ` [PATCH v7 3/5] config: learn `git_protected_config()` Glen Choo via GitGitGadget
2022-07-07 23:01             ` [PATCH v7 4/5] safe.directory: use git_protected_config() Glen Choo via GitGitGadget
2022-07-07 23:01             ` [PATCH v7 5/5] setup.c: create `discovery.bare` Glen Choo via GitGitGadget
2022-07-08  1:07             ` [PATCH v7 0/5] config: introduce discovery.bare and protected config Junio C Hamano
2022-07-08 20:35               ` Glen Choo
2022-07-12 22:11                 ` Glen Choo
2022-07-14 21:27             ` [PATCH v8 0/5] config: introduce safe.bareRepository " Glen Choo via GitGitGadget
2022-07-14 21:27               ` [PATCH v8 1/5] Documentation/git-config.txt: add SCOPES section Glen Choo via GitGitGadget
2022-07-14 21:27               ` [PATCH v8 2/5] Documentation: define protected configuration Glen Choo via GitGitGadget
2022-07-14 21:27               ` [PATCH v8 3/5] config: learn `git_protected_config()` Glen Choo via GitGitGadget
2022-07-25 18:26                 ` SANITIZE=address failure on master (was: [PATCH v8 3/5] config: learn `git_protected_config()`) Ævar Arnfjörð Bjarmason
2022-07-25 20:15                   ` Glen Choo
2022-07-25 20:41                     ` Ævar Arnfjörð Bjarmason
2022-07-25 20:56                       ` Glen Choo
2022-07-14 21:28               ` [PATCH v8 4/5] safe.directory: use git_protected_config() Glen Choo via GitGitGadget
2022-07-14 21:28               ` [PATCH v8 5/5] setup.c: create `safe.bareRepository` Glen Choo via GitGitGadget

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: http://vger.kernel.org/majordomo-info.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=7499a2809615d42eaf3649e1c33f38d099d27c1a.1653685761.git.gitgitgadget@gmail.com \
    --to=gitgitgadget@gmail.com \
    --cc=chooglen@google.com \
    --cc=derrickstolee@github.com \
    --cc=emilyshaffer@google.com \
    --cc=git@vger.kernel.org \
    --cc=gitster@pobox.com \
    --cc=me@ttaylorr.com \
    --cc=sandals@crustytoothpaste.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
Code repositories for project(s) associated with this inbox:

	https://80x24.org/mirrors/git.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).