Re: [PATCH v2 3/3] environment: move trust_executable_bit into repo_config_values

> Move the global 'trust_executable_bit' configurations
> into the repository-specific 'repo_config_values'
> struct. To ensure code readability, the getter functions
> 'repo_trust_executable_bit()' has been introduced.
> 
> For now, associated functions access this configuration by
> explicitly falling back to 'the_repository'.
> 
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Ayush Chandekar <ayu.chandekar@gmail.com>
> Mentored-by: Olamide Caleb Bello <belkid98@gmail.com>
> Signed-off-by: Tian Yuchen <cat@malon.dev>
> ---
>   apply.c       |  2 +-
>   environment.c | 11 +++++++++--
>   environment.h |  9 ++++++++-
>   read-cache.c  |  8 ++++----
>   4 files changed, 22 insertions(+), 8 deletions(-)
> 
> diff --git a/apply.c b/apply.c
> index 249248d4f2..fbb907d3c0 100644
> --- a/apply.c
> +++ b/apply.c
> @@ -3893,7 +3893,7 @@ static int check_preimage(struct apply_state *state,
>   		if (*ce && !(*ce)->ce_mode)
>   			BUG("ce_mode == 0 for path '%s'", old_name);
>   
> -		if (trust_executable_bit || !S_ISREG(st->st_mode))
> +		if (repo_trust_executable_bit(the_repository) || !S_ISREG(st->st_mode))
>   			st_mode = ce_mode_from_stat(*ce, st->st_mode);
>   		else if (*ce)
>   			st_mode = (*ce)->ce_mode;
> diff --git a/environment.c b/environment.c
> index fc3ed8bb1c..75069a884d 100644
> --- a/environment.c
> +++ b/environment.c
> @@ -41,7 +41,6 @@
>   static int pack_compression_seen;
>   static int zlib_compression_seen;
>   
> -int trust_executable_bit = 1;
>   int trust_ctime = 1;
>   int check_stat = 1;
>   int has_symlinks = 1;
> @@ -142,6 +141,13 @@ int is_bare_repository(void)
>   	return is_bare_repository_cfg && !repo_get_work_tree(the_repository);
>   }
>   
> +int repo_trust_executable_bit(struct repository *repo)
> +{
> +	return repo->gitdir?
> +		repo_config_values(repo)->trust_executable_bit :
> +		1;
> +}
> +
>   int have_git_dir(void)
>   {
>   	return startup_info->have_repository
> @@ -305,7 +311,7 @@ int git_default_core_config(const char *var, const char *value,
>   
>   	/* This needs a better name */
>   	if (!strcmp(var, "core.filemode")) {
> -		trust_executable_bit = git_config_bool(var, value);
> +		cfg->trust_executable_bit = git_config_bool(var, value);
>   		return 0;
>   	}
>   	if (!strcmp(var, "core.trustctime")) {
> @@ -720,5 +726,6 @@ void repo_config_values_init(struct repo_config_values *cfg)
>   {
>   	cfg->attributes_file = NULL;
>   	cfg->apply_sparse_checkout = 0;
> +	cfg->trust_executable_bit = 1;
>   	cfg->branch_track = BRANCH_TRACK_REMOTE;
>   }
> diff --git a/environment.h b/environment.h
> index 123a71cdc8..44b97be654 100644
> --- a/environment.h
> +++ b/environment.h
> @@ -91,6 +91,7 @@ struct repo_config_values {
>   	/* section "core" config values */
>   	char *attributes_file;
>   	int apply_sparse_checkout;
> +	int trust_executable_bit;
>   
>   	/* section "branch" config values */
>   	enum branch_track branch_track;
> @@ -123,6 +124,13 @@ int git_default_config(const char *, const char *,
>   int git_default_core_config(const char *var, const char *value,
>   			    const struct config_context *ctx, void *cb);
>   
> +/*
> + * Getters for the `repo_trust_executable_bit` fields of `struct repo_config_values`.
> + * They check `repo->gitdir` to prevent calling repo_config_values()
> + * before the configuration is loaded or in bare environments.
> + */
> +int repo_trust_executable_bit(struct repository *repo);
> +
>   void repo_config_values_init(struct repo_config_values *cfg);
>   
>   /*
> @@ -160,7 +168,6 @@ int is_bare_repository(void);
>   extern char *git_work_tree_cfg;
>   
>   /* Environment bits from configuration mechanism */
> -extern int trust_executable_bit;
>   extern int trust_ctime;
>   extern int check_stat;
>   extern int has_symlinks;
> diff --git a/read-cache.c b/read-cache.c
> index cb4f4878c8..89f5c88c58 100644
> --- a/read-cache.c
> +++ b/read-cache.c
> @@ -214,7 +214,7 @@ unsigned int ce_mode_from_stat(const struct cache_entry *ce, unsigned int mode)
>   	if (!has_symlinks && S_ISREG(mode) &&
>   	    ce && S_ISLNK(ce->ce_mode))
>   		return ce->ce_mode;
> -	if (!trust_executable_bit && S_ISREG(mode)) {
> +	if (!repo_trust_executable_bit(the_repository) && S_ISREG(mode)) {
>   		if (ce && S_ISREG(ce->ce_mode))
>   			return ce->ce_mode;
>   		return create_ce_mode(0666);
> @@ -228,7 +228,7 @@ static unsigned int st_mode_from_ce(const struct cache_entry *ce)
>   	case S_IFLNK:
>   		return has_symlinks ? S_IFLNK : (S_IFREG | 0644);
>   	case S_IFREG:
> -		return (ce->ce_mode & (trust_executable_bit ? 0755 : 0644)) | S_IFREG;
> +		return (ce->ce_mode & (repo_trust_executable_bit(the_repository) ? 0755 : 0644)) | S_IFREG;
>   	case S_IFGITLINK:
>   		return S_IFDIR | 0755;
>   	case S_IFDIR:
> @@ -338,7 +338,7 @@ static int ce_match_stat_basic(const struct cache_entry *ce, struct stat *st)
>   		/* We consider only the owner x bit to be relevant for
>   		 * "mode changes"
>   		 */
> -		if (trust_executable_bit &&
> +		if (repo_trust_executable_bit(the_repository) &&
>   		    (0100 & (ce->ce_mode ^ st->st_mode)))
>   			changed |= MODE_CHANGED;
>   		break;
> @@ -759,7 +759,7 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
>   		ce->ce_flags |= CE_INTENT_TO_ADD;
>   
>   
> -	if (trust_executable_bit && has_symlinks) {
> +	if (repo_trust_executable_bit(the_repository) && has_symlinks) {
>   		ce->ce_mode = create_ce_mode(st_mode);
>   	} else {
>   		/* If there is an existing entry, pick the mode bits and type